CA1119403A - Heat sink imaging method and apparatus for live skin tissue using pulsed energy source - Google Patents

Abstract

HEAT-SINK IMAGING METHOD
AND APPARATUS FOR LIVE SKIN TISSUE
USING PULSED ENERGY SOURCE

Abstract of the Disclosure The imaging layer coated side of a heat-responsive recording medium is selectively heat-sinked by the raised portions of live skin tissue contacting the same so that only the unheat-sinked portions of the recording medium will reach an imaging temperature. The source of heat for the film may be a flash lamp directed against the opposite substrate side of the film where the electromagnetic energy thereof is converted into heat when absorbed by the substrate, or may be a source of externally applied heat transmitted through the substrate to the imaging layer of the film. In the latter case, the recording medium is preferably initally in spaced relationship with a heat contact plate which is to be contacted by a heat source, which may be the end face of a piston either pre-heated to a given temperature or having a current heatable resistance thereon to be pulsed with current. In the former case the plunger end face preferably has a low heat conductivity coating thereon. The live skin tissue, like a finger, is pressed against the imaging layer coated side of the recording medium to bring the substrate side thereof against the heat contact plate which receives heat from the piston end face. The plunger is automatically withdrawn from the heat contact plate a short time after the recording medium is pressed against the heat contact plate to prevent any discomfort or burning of the finger.

Description

i!
. ~ ~ 9403 -2 Backqround of the Invention This inven-~ion deals with a method and apparatus for recording the surface topolog~ of live skin -tissue.

}ieretofore, the recording o~ fincJerprin-ts has generally been obtained by coating the fingers with ink and then transferxing the ink-formed image onto a piece of paper.
This is a very messy and inconvenient me-thod of recording fingerprints, and methods and apparatus for recording finger- !
prints without the use of ink or other chemicals have not until recently been developed which are suficiently easy to carry out o~ use to be feasible for use in police ~ta-tions and the like.

Many techniques have been deveioped for recording the surace tJopolo~y of skin and other tissue. Some o~ these methods involve taking microscopic pictures of tiss~ue severed `
from the human body~ In such case, recorded images are generall , ~ormed on high resolution silver halide film, requiring a time-consuming~developing process which does not make the skin topology involved immediately available to the doctor or researcher Such processes are not conveni~nt for obtaining the tissue topology of live skin, since it is no-t feasible to place the particular area of the body involved into the field of~a microscope where, to take effective picture, the skin involved must be pressed asainst a ~lat surface to obtain perEecLI~ focused ima~e5 of the entire skln area, while i ~ - 2 ~

projecting ligh-t upon the skin area involved whlch i5 necessa~y to expose the film.

IJ.S. Pa-tent No. 3,533,823 to W. ~I. Newklrk et al dis-closes a method of'making a fingerprin-t when a fin~er is pre'~sed upon an imaginy material coated on a mctal su~,strate heated to a temperature substantially above room temperature but suf~iciently low as not to burn the users fingersv The imag:ing material is one which has a hysteresis characteristic where the film initially~
~as a very low reflectivity (i.e. black) at room temperature.' When elevated above room temperature it progressively becomes more reflective (evg. approaching a pure red coior). ,The imayiny ¦
layer has a yiven degree of reflectivity prior to the application of a finger thereto. When a finger is placed upon the imaging layer, the points thereo~ contacted by the ridcJes o~ the ~in~er , ¦
cool the same so that these portions of the imaying layer will have a different ~eyree of reflectivity. ,When the ~inger is re-moved from the imaging layer, the portions th~ereof previously cooled are heated to the same temperature as thel rest of ~he same.l However,,because of the hysteresis effec~ of the im~ying la~er the degr~e of reflectivity of the previously cool~d portions of the imaginy layer will be different frorn those not oriyinally con-tacked by the ridges of the finger. The pattern of the ridges of ¦
the user's finyer will, therefore, be present on th~ imaging layer until the temperature'of the imaying la~er is lowered to room temperat~re where all color differen~iation therein disappears, A~
photograph of the original imprint must thus be,taken to obtain a permanent record of the :~ingerp~int. The require~ent of a - 3 - ' _ ,.,~, _ . . ,, . _ __ ~ _._ . _, . ~, _ _ __,_. _ __~ _ . ._ __ _ ., _ _, . _ _ . . _. __ . . .

' ~ 111Y403 camera as p,~rt of thc proccss of providincJ a permanent record of ¦
. ¦ a fin~erp.rint makes the process involved a very unwieldly one.
¦¦ The only advantage of this process over finyerprinting process utilized pxior thereto is that it avoids the necessity of using.
mess~ f.ingerprin-t ink or other chem.icals on the finger.

U.S. Patent No. 3,070,428 to Cohen discloses a process . ¦ for reproducing negative images of the raised por-tion of metal il sur.faces applied to the imaging layers of Thermofax papers or ¦¦ transparencies which must be bulk-heated to ~ubs-ta.ntially elevated I! temperatures as disclosed in this patent. These temperatures fall ¦¦ in the range of from about 50 to 250C. The speci.Eic examples ¦ given in the patent speciEy 5 or more seconds o~ heat applica-tion to achie~e the desired results. The areas of the Thexmofax ¦
: I paper engaged by the raised portlons of a metal surface are . cooled thereby, so that these portions thereo~ are not a~fected l by the heat, whereas those portions thereof not contacted b~ the :~: metal surface are heat-imaged to a dark color, black in the ~ example given in the patent.
. . .
The process for reproducing negative images of metal surfaces disclosed in this Cohen patent would appear no-t suit-able for makiny fincJerprints. 'Thus r the necessity of bulk heating the substrate of the papers xequires he~t application .
times to raise the temperature of the paper to the high imaging termperatures that would cause at least a ris}; oE sexious discomfort and probably would cause a serious risk of hurning a user's finger~should the process clisclosed be used to obtain f.ingerpxints. Also, since hea-t applic;ation time of.the order of ,: ..' , . . I

. ,.~

~. 5 magni-tude o:E 5 or more seconds i5 required wi-th the specific recording papers and temperatures disclosed in -this patent, there is a ris~ of smudgincJ the image since the person holding the finger on the paper involved can usually move his finger relative to the paper within that time involved. ~lso, in SUC}I a long period o-f time, it is possible that heat spxe~ding parallel to the paper can prevent hiyh resolutlon imaging, even if the user's !
finger were to remain stationary on the paper for such a long perioa of time. While imaging times can possibl~ be reduced by using higher imaging temperatures, this can raise the ris}c of burning the paper and causing greater discomort or damage to the user's flngers.

Relatively recently, a fingerprinting s~stem was devel- !
oped where fingerprints a.re applied to the back of a chec~ ior . ¦
identifying the person cashing the check. In this sy~tem, the user must first impregnate a fingertip. with a chemical material after wh~ich he presses his chemical coated fingertip upon a chem-ically treated section of the chec~ (or a pressure sensitive coated paper to be applied thereto) to leave an imprint oE his fingerprint thereon. While this fingerprin-t system avoids the use o~ messy inks, it, never-theless, leaves ~n undesirable chemi-cal odor on the userls finger until it is washed off. ~150, the image produced is not always of the most satisfactory clarity,and it is believed that it does not have arch.ival properties which would be neaessary, for example, for fingerprinting records which are to be ~ept for an indefinite period, as in the case of police and sec~rity syster 'ingerprint records ~ ( ' I - 5 - l .~ .~ . .... 1! . I

i . - 6 I
. i It is, aecordin~ly, an object of the inven-tion to pxo-¦ vide a proeess and apparatus for providing an immediate reeora of ¦¦ the surfaee topolo~y of live skin tissue and which do no-t require .
¦ conventional photo~raphic e~uipment or the applieation o~ any.ink or ehemicals to the skin tissue surEace involved. ~ related ~. I objeet oE the most preferred ~orm of the invention is to pro~ide ~ J ¦ a process and apparatus as just deseribed wherein the cost oE
: ¦ produeing such a record is eompetitive with saicl low eost finger-¦i print systems for use on checks just deseribed. .

¦¦ A further objeet of the.inve,ntion is to provide a me-thod I
: I and apparatus satisfying one or more of the above-stated objeck- ¦
-~ ives whieh produees a recorc1 of live ski.n tissue sur~ace topologie,s . immediateIy upon exposure of the recording -Eilm to radian~.energy:,¦
.~ like an Xenon flash lamp or the like, or to externally appli~d heat, and:without using any chemieals or other eonsumable mater-ials. A still further objeet oE the invention is to provide a method and apparatus as just described whlch does not raise any ~ ~ . ~
.. 'serious risk o~ burnin~ or discomfort to the l~ve skin tissue I 'involved. ., , - . ,, ~ ' . ' ' .' ' ,'.
. ~nother object o~ the invention is to~provide a method ; . and apparatus satisEying one or more oE the above-stated objeet-ives whieh has sueh a high de~ree of resolution that details which ~ ~ ~ are elearly eeorded are as small as about 3-5 mieron in size. -.

; ~ further objec-t of the invention is to provicle a method ¦
¦ and apparatus as described where unskilled personnel ean be used : ¦ to praetice the method or operate,the apparatus thereof.
, 11 ' , ." I , ' , ' .
~ I
,- I q ~1 - 6 -~ ur copendiny Canadian Application Serial No. 332,467, filed July 24, 197~ discloses a method and apparatus which achieves most of the aforesaid objectives where a source of electromagnetic energy is utilized. The recording film used in the method and apparatus disclosed in this application is a dry process recording film, (most advantageously a dispersion-type film as disclosed in this application) which utilizes a substantially opaque layer of an imaging material deposited on a transparent substrate which, upon application thereto of electromagnetic energy of at least a given critical or threshold level, transmits the energy to the imaging material where the energy is absorbed to produce heat, which raises the unheat-sinked portions thereof to a temperature which causes the opaque imaging layer to become relatively transparent. The film involved can be a high contrast film, but it is preferably a conkinuous tone type of film wherein there is associated with the imaging layer means for varying the degree of transparency achieved in proportion to the temperature of the imaging layer.
The invention disclosed in this application resulted from a discovery that when the ball of a finger was brought against the imaging mater1al coated side of a dispersion recording film and a flash of radiant energy of a Xenon flash lamp lasting for a small fraction of a second, like that commonly used in taking flash photographs ~i.e. typically no greater than about 1~1000 second)/ was applied through the transparent, substrate side of the film during only the period when the finger contacted the film, there was pro-ws/ ,.: i B

duced an extremely clear transparency fingerprint record where . the depressions in the finger surface a~peared in the transparent ¦l imaged portions o the film and at least the peak portions ~f the ¦¦ surface appeared in the relatively opa~ue portions of the film.
hen the fingerprint was projected in greatly ma~nified ~orm on a j screen or photographic film subsequen-tly developed, microscopl-¦l cally small details, like pores and o-ther minute depressiorls, ; ! become clearly visible, Moreover, when a con-tinuous tone form of I film is used, a degree of transparency is produced in the portions : I of the film confronted by the various portions of -the inger in - ¦¦ accordance with the intimacy of contact between the various points -¦ of the finger surface involved~and the recording fi~m, which pro- I
. ¦ duces a three-dimensional visual effect.. The dispersion types of films disclosed in~this application have archival pro~ertles and~
do not require any special storage condi-tions : O great importance is the fac-t tba-t no rlsk oL discom-: , ¦ fort or harm to live skin tissue results Erom this imacJing system . since the electroma~netic energy from the flash lamp applled for a ve small fraction oE a seco d does not devel p a su Li~i-nt : .' . ~ . l . _ ' . I
'... _ ' ' . I
.. -- . .. . ..... ... .. . . _ _ _ _ . .. I

ll 1119403 ,1 - 9 I! qUalltity of heat eneryy in the imagln~ layer as to crcate any ¦l discomfort in the user's skin whatsoever.

The dispersion type recording films dcscribed above ~ave extremel~ good archival properties ancl this fact, toc3e-ther wi.~h ,I the fact that a transparency is produced by the process whic~
enables im~ediate readily projection of the fincJerprin~.ima~e ' involved onto a projection screen, the heat-sink imaginy me-thod .1 and apparatus disclosed in this application are pre~erable ~or ', most app,licationsO For applications where cost considerations are ., ',i . I
il paramount, such as in the application of finyerprints to the rear ,1 of checks and the lik~/ and archival prope.rties aA,re not necessary, ,, recording films other than dispersion-type recording films may be ¦¦ more desirable. Thus, another object of thi. present .i~nvention is ,I to provide a method and apparatus for providing an immèd,iate image ,¦ of live skin tissue without the need ~or conventional p~otograph-lC equipment or inks or other chem,icals appli~d to the skin tissue ~- I! involved and where the recording film utilized need not be the : ,. I dispersion-type,recording films disclosed in the pre~iously` iden-¦ tified applications or:other- f.ilms having transparent subst~ates.
. . .
, , I Another object of the invention is to provide a me-thod ¦ and apparatus satisfying one or more of the above-stated object-.. , ives where the energy for imaging the recordin~ med.ium may be a OE source of heat genera~ed externally to the imay.ing layer an~ where there is little risk or discomEort or damage to the live skin tissue invo ve6. ~ related oh]e-t oE the invention is .o provide ~ S
~ 9 _ Il , 1119403 ~ lO

I a method and apparatus as just described which are co~t competi--l tive with the previously described fingerprint systems for use on I checks. .

g Su~nmary of the Invention C ¦ ' ' The invention provides a record of the surEace topology of live skin tissue utiliziny the heat-sinki.ncJ effect of the : ¦ raised porti.ons of such live skin tissue in a recording method ¦ and apparatus where heat is conduc-ted to the imaging layer of a .
heat-responsive recordincJ medium from the substrate thereof and ¦ in a manner where there is llttle or no risk of discomort or :~ . damage to the live skin tissue. This is ~achieved in a number o different ways, dependiny upon the particular form of the invèn-. tion involved. The live skin tissue is pressed agains the heat-responsive outer imaging layèr of a recording medium duxi~lg the application of a shortpulse of either substxate absorbed elec-tro~
. ~ . magnetic energy or ext.ernally generated heat to,the su~s~rate o~
: ~ ... the recording medium. The heat-sinking effect'o.~ the raisea portions,of the live skin tissue produces good images of the , . surface topology o~ khe live skin'tissue when the amount o~ energy :~ . transmitted to the substrate is properly makched to the degree o heat-si~kiny achieved by the live skin tissue. Also, particul,arly ~, where externally yeneraked heat is applied to the substrate oE
. the recording medlum, in addition to applylng a short pulse of heat to the recording med.ium the risk of discomfort or damage to the live s~in tissue is reduced by controllinJ' the quantit~ o.f ,.......... ¦ h_at which is transmitted to the recording medium. , ( . .1 . I , - 10-~ t ~

19~03 ~ f -the source of enercJy for producing heat in the sub-strate of the r~cording medium is a source of pulsed electrom~g-netic energy, like the radiant ener~y output of a Xenon fl~sh lamp, thc substra-te of the recoxd-ing medium has incorporated there.i suitable materials which efficiently absoxb, for example, the infrared spectrum components of the rad.iant ~nergy produced by the Xenon flash lamp. Xncorporating in the substrate o~ t~e recordiny medium particles of infrared absorbiny pigmen-t can produce efficient absorption of infrared radiation to ge~erate su~Eicient heat to effectively image the outer imaging layers used in a number of presently available heat responsive recording papers.

While, in ~me cases, the use oE radian-t ener~y sources as a souxce of producing heat in the subs.trate of the recording "
medium have advantages over the use of externaIly ~en~rated heat,j such as ease of control of the duration of the radiant energy, there are applications where it is more advantageous to use ex-tex nally generated heat for this purpose. .Thus, it may ~e desirablej from a cost standpoint to use an available heat-responsive recordji paper which does not have a sufficiently ef~ici~nt radiant energ~;
absorbing substrate to produce satisfactory imac3es of l.ivé skin tissue~ Also, production of live skin tissue image-producing qu ities of heat in the substrate of the recording mediums from radi .
ant ener~y may require high power radiant ener~y sources which are too costly or which have too limit.ed a li~e.
. , , .
¦ In the applicat.ion of the invention where externally ¦ generated heat is applied to the substra-te of the recoraing mediu ¦~ the heat source may, for example, be a metal body like a ho-t-plc~t~

~ ntaining current-carryin~ Fe-istance element6 wlero current 9 403 ~ 12 ¦ flow therethrough is con-trolled to mainta:in the outer face ~f the ¦ metal body at a given predetermined temperature (which ~oul~
I generally be in excess o~ the imaging temperature required ~or the ¦ imaging layer of the recording medium involved). Xn the alter~
native, ~he heat source could be a body of a heat insulating ¦I material carrying on the outer face thereof a ribbon-like resis-tance elemenk which receives a curren-t pulse of~desired width to produce sufficient heat momentarily in the ribbon-like resistance Il element to e~fect imaging o~ the recording medium broughk there-i against-11 ' . ' ~
Il Whether the energy source for producing heat in the sub- i ; strate is a source oE radiant energy or a source of ex-ternally generated heat as described, there is most advan-tageousl~ provided' what will be sometimes xeferred to as an energy tr~nsmitting and contact me~er or heat storiny member agains-t Which the s~bstrate side of the recording medium is pressed by the live skin tissue.
This member is preferably spring mounted for inward movement over a given distance to bring it in-to a position against or n~arest the energy source when the pressure of the live skin tissue ~gains :
r r I the recording medium and such memher will cause optimum intimate ¦ contact o~ the tissue wlth the recording medium for ~ood, image-¦ producing heat-sinking by the live skin tissue involved. In such case, control means are provided responsive to a given amoun-t of ¦ movement oE the energ~ transmitting and conta~t membex ~or initi-ating and/or applying energy to the recording medium through said eneryy transmittihg and contact member ~or a given desired limited i period.
' ' (' ~ I ~

I I . .. ... . . ......... ~

1 Especially in the case where the eneryy applied through - I the energy transmitting and contact member is a hea-ted metal body j maintained at a given h.i~h temperature, to minimi7Je the risk of I¦ discomfort or damage to the live skin tissu~ involved, the control means~ upon sens.ing said given amount of movement of said energy ¦¦ transmittinc3 and contact member, effects withdrawal of the metal ~ li body from contact with the energy transmittinCJ and contact mer~ber : ¦~ a short period aEter the live s~in tissue has pressed the record-ing medium (initially spaced from the energy transmittin~ and . , contact member) against the member, to e~fect inward movemen-t ;~ I thereo. While the risk oi discomfo~t or burninc~ o:~ the live skin;
j tissue involved is perhaps less in the case where -the heat source . is a ribbon-like resistance element carried on a body of heat : insulating material and moMe`nta~ily pulsed wikh current when the : . control means senses said yiven amount of movement oE ~he energy . transmittincJ and contact me~ber, such risk is further minimized if the ribbon-like resistance element is wi-thdraw~:from con-tact . with the enercJy transmitting and contact member a short period aftex the recorcding medium is brought ac3ainst the same by the pressure of~the live skin tissue. '' ~ In accordance with a further ~eature of the invention, to : 1 minimize the risk of discomfort or dama~e to the :live skin tissue ¦
. I wher~ the externally ge~erated heat source is in the form of a heal metal body surface maintai.ned at a given predetermined temperaturel, there is most advantageously positioned be-tween the heated metal body and the energy transmittin~ and control member a layer o~.
. . ~ . "

~ !i - I

I - 13 - ~ ~

9~03 naterial having a relatively low heat conductivity, so that heat is transmitted through such material to the member relatively slowly. ~he heated metal body may carry the layer of low heat conductivity material carried on the outer face thereof. The energy transmitting and contact member, initially continuously applied to the heated metal body, is here designed to be a heat storing member which stores a sufficient amount of heat at the control temperature of the heated metal body so that, upon the pressing of the recording medium by the live skin tissue against such member, an adequate amount of heat will rapidly be conducted to the substrate of the recording medium to cause satisfactory imaging of the imaging layer. The layer of relatively l~w heat conductivity material then allows heat to pass from the heated metal body to the energy transmitting and contact member so slowly that there is little or no risk of discomfort or damage to the live~
~ skin tissue, even if a malfunction of the heated metal body ; withdrawing control means should occur.

In accordance with a further feature of the invention, the heated body to be withdrawn from the energy transmitting and contact member may comprise a solenoid-operated plunger outwardly spring urged energy transmitting and contact member so that both of these elements move inwardly together as the pressure of the live skin tissue against the recording medium presses against the energy transmitting and contact member to move the same against a stop shoulder, whereupon the previously mentioned timing operation begins and ends in the withdrawal of the plunger from the member.

In summary, the aforementioned objects and features may be broadly defined in one aspect as a method of recording the surface topology of live skin tissue comprising the steps of, providing a recolding medium having a substrate B~ 1~
~1S/

` upon one s.ide of which there is a layer o~ a heat-responsive-imaging ma-terial which, upon conduction of a given amount of heat energy to any given portion thereof will be heated to a given imaging temperature in the absence of any substantial heat-sinking applied to the one side of the recording medium, applying the live skin tissue against the imaging layer containing side of the recording medium so that projecting portions of the live skin tissue act as effective heat-sinks at the points where it is most contiguous thereto to dissipate heat thereat to an extent where the imaging material i5 not ~' imaged appreciably, if at all, by the amount of heat energy conducted to the portion of the imaging material involved fromthe substrate and wherein the heat-sinking effect of the live skin tissue where recessed portions thereo~ are located is - ~o minimal as not to prevent the given amount of heat energy from raising the temperature of the portion of the recording ~ . medium involved to the imaging temperature, and then applying '' a pulse of energy to the substrate side of the recording ; ~medium which will provide heat energy in the substrate which ~ 20 is conducted in at least the given amount to each of the various ,~ portions of the layer of imaging material, the pulse of energybeing applied to the substrate side of the recording medium only while the live skin tissue is in contact with the recording medium.
As a second aspect of the present invention there is a provided a recording system for recording the surface topology of live skin tissue, the recording system comprising an energy transmitting and contact member spring mounted for a given predetermined inward movement when a given lnward pressure is applied thereto, a heat imageable recording medium supported in confron-tlng rel.ation to one side of the energy transmi-tti.ng and contact member, which recording medium a-g~L~)3 is to be brought into contact with the energy transmitting and contact member to depress the same when an image of the live skin tissue is to be made, the recording medium comprising a substrate facing the member and upon the outer side oE which there is a layer o~ a heat-responsive imaging material exposed to be engaged by the live skin tissue, and which, upon conduction of a given amount of h~at energy to any given portion thereof, will be heated to a given imaging temperature in the absence of any substantial heat-sinking applied to the outer side of the recording medium, energy applying means for applying energy to the heat transmitting and contact member which energy ~ is transmitted to the substrate of the recording medium to : provide heat energy thereln in sufficient amounts to effect ;~ conduction of at least the given amount of heat energy to each :. of the various portions of the layer of imaging material of the recording medium, to provide selective imaging of unheat-sin~ed : or minimally heat sinked portions of the layer of imaging material, and means responsive to a given movement of the energy transmitting and contact member for applying the `~ 20 energy to the member for a predetermined period.

The invention also contemplates an apparatus :Eor recording the surface topology of l:ive skin tissue, the apparatus comprising a recordiny station and a recording strip-severing station, a strip of imageable recording material extending by the recording and strip-severing stations, the strip of recording material having an imaging layer on one side thereof, the recording station lncluding imaging means responsive to application of a given live skin tissue pressure to the strip of recording material by providing an image of the surface topology of the skin tissue applied thereto, means for automatically advancing the imaged portion of the strip of recording material to the strip-severing station when pressu.re on the strip of recordiny ma~erial is relieved, the B -14b-ws/

9~al3 strip-severing station including strip-severing means mounted for movement between an inoperative position and an opera-tive position where the imaged portion of the strip of material is severed from the rest of the same, and means for operating the strip-severing means.
The above and other ob~ects, advantages and features of the invention will become more apparent upon making reference to the specification and claims to follow and the drawings.

-14c-ws/ ' B

escription of DrawincJ.s ~

Flg. lA shows one fo~m of ~he .invenLion includ;ng a frag-mentary greatl~ enlarcJed sec-tional view oE a heat--responsi~e recording paper, to the imagincJ layer side oE which is applied live skin tissue and to the substra-te side of which is applied a source of radian-t ener~y directed through a ligh-t dispersiny prism also shown in fracJmentary cross section, said figure further showing in block diagram form the energization circuit for the source of radiant energy;

Fig. lB is a fragmentary sectional view of the portion o the recording paper shown ln Fig. 'lA~ with the image produced 'therein of the raised portions of the live skin tissue shown in Fig. lA; f , '' ' Fig. 2A shows another form of the inven-tion including a, greatly enlarged sectional Vi2W of a recordincJ paper like that shown in Fig. lA, spaced supports for the,recording paper, and a source of heat energy and associated outer heat insulating and ' heat storage layers,to which the recording paper is applied during an im,aging oper,ation, said figure further showing in block diagram form the energization circui-t for heating wires forminy part oE
the source of heat energy;

Pig. 2B shows part of the heat insulat.ing laye'r ~nd the recording paper shown in Fig. 2A as the raised portions o~ the live skin tissue contact the imac3incJ layer side of the recording paper and press the same against the heat storage layer to heat-sink the yortions of the recorcling medium contacted thereby as heat ¦is conducted to the substrate and imaging layers of -the recording paper from the heat storage layeri . I ~ :
~ ' ' - 15'-1119403 - l6 I~ig 2C ahows the portion of Lhe rocording p~per illus-trated in ~ig. 2B, with the :image produced -therein of the raised portions of the live skin tissue shown in Fig. 2B;

Fig. 3~ is a fracJrnen-taxy enlarged sectional view through a recoxding film, space suppor-ts thereEor r a spring muunted heat s-torage member initially spaced from the recording film, and a spring mounted, solenoid-operated heated metal plunger ha~ing a heat insulating layer covering the outer face -t~lereof, said fiyure also showing in hlock diagram form the energizin~ and control circuits for the heating elements in the metal plunc3er and the solenoid for reciprocating the same;

Fig. 3B shows the equipment shown in Fig. 3~ as -the recording film is pressed by the live skin :tissue agains~ the heat storage member which, in turn, is prèssed against the outex.face of the heat insulatlng layer covered plunger;

Fig. 3C shows the equipment shown in Flc3. 3B a short timel period thereafter when a timer effects energization of the solenoi~l shown in Fig~ 3B, to withdraw the plunger from contact with the heat storage member as or immediately after the recor~ing film has¦
been imaged by the live skin t.~ssue pressed thereaJainst;

Fig.. 4 is a greatly enlarged fragmentary sectional view of a recording pape.r, space supports therefor, a spring-mounted heat transmitting and contact member, and a ribbon like resistance element against the inn~r side of the heat transmitting and con- !
tact member, sai~ figure further showing the energizing and contro]
¦circuit for e ribbon-llke resistaDce elementi -16- 1, lli9403 li - 17 ! Fig. 5A is a schematic diacJram showing various elements !i of a preferred apparatus for recording and applying a ~ingerpri.nt to the rear of a chec~, which appara-tus includes as a part there-of the imaging apparatus sho~n in Figs. 3~, 3B and 3C; and ig~ 5B is a g.reatly enlaryed, fragmen-tary sec-tional view through a strip of recording film used in the apparatus o~ Fig. 5A~
which recording film is modifled in .that it includes release and pressure sensitive adhesive layers thereon. ~ .
.

' t ` - ' I

l! . .. l ;l . ..

~ - 17 - ~

~ I
. ~ 94~3 -- 18 - Description of Exemplary Embodi~ent o the Invention Refer now more par;ticularly to the embodimen~ of the invention shown in F.i~. lA. A recording mediurnr li~;e a heat-responsive recording paper, having a heat-responsive imaging layer 2a deposited on a substrate 2b made of a radiant energy absorbing material,is shown being con-tacted at a recording station 1 by the raised portions 4d and 4e of a body of live skin tissue4, like the end of a finger. This figure shows the live skin tissue 4 pressing against the imaging layer slde of recording medium 2l in turn, pressed thereby against the outer face of a light disper sing prism 6. (The light dispersing prism 6 constitutes what is sometimes referred to as an energy transmitting and con-tact member.) :The prism 6 is urged into an outer position ~y spring means B. ~hen the pressure of the live skin tissue 4 reaches an optimum leveL for good heat-sinking of the recording medium 2,the spring means 8 becomes depressed to a degree that .a position sens-¦
ing means,which may.be in the form of a micro-switch means 12.
having a position sensing arm 12a underlyin~ a par.t of the prism 6,is operated to effect operation of a control means 14 to produce¦
:the necessar~ voltages to moment.arily energize a source of.radiant!
energy lQ, which may be a conventional Xenon flash lamp. A source of energizing voltage 16.is shown connected to the control means which, where khe source of radiant eneryy 1.0 is a convenkional Xenon flash lamp, effects the generation of a trigger pulse and the discharge of a capacitor.through the flash lamp in a conven-tional well-known way common in ~he operation of flash lamps for cameras.

I ' ~, .
- 11 ' ~L~19403 The rays lOa of electromagnetic ener~y lOa ~mana-tecl from Il the radiant energy source 10 pass into and are di:Efused by the Il prism 6, so that they are conducted fai.rly evenly to ~he~various ii portions of the substrate 2h of the recording medium 2.. ~G pre-viously indicated, the substrate 2b cornpriSeE. one or morc ~ter-tj ials which absorb a suficient portion of the ~lectromagne~
. energy from ~le radiant energy source 10 that sufficient h~ is produced in the substrate 2b to eEfect imaying oE the unhea~ .
, , .
l~ sinked poxtions of the imacJing layer 2a. Accordingly, as s~Q~m in¦' Fig. lB, ~hose portions 14a, 14b and 14c of the imaging lay~ ~a i~ which ~ere opposite the xecessed portions 4a, 4b and 4c oE 3th~
¦ ¦l live skin tissue 4 will be imaged so as to produce a.contrasting ~¦ appearance to ~ha:t of the portions 14d and 14e of the :imaging ~¦ layer 2a contacted by the raised portions 4d and ~e of the live skin t_ssue~

. I The recordin~ medium 2 may be of a type exempl.i.fled by some of -the various presently available heat-responsive recording . papers having a substrate o~ papex or an opaque synthetic plastic ; material,with added materials, where necessary, to enable them to absorb sufficient amounts of the energy from-the rays lOa o.f.the . particular radi.ant energy source 10 used therewi-th to produc~
heat which will image the.imac~ing layer used therewith. ~ful.
heat-responsive xecording papers of -the type described are ~ ~ presently being manufactured by Mi-tsubishi Pape.r Mills, L~
I . Texas Instruments, Inc. and Minneso-ta Mining and Manufacturin~
¦ Company, the latter papers under the trademark TNERUO~X. ~.S.

Patellt No. 3,953,659 of -the Texas Ins-trumen-ts, Inc. ancl U S.
!¦ Patent No. 4,032,692 of Mi-tsubishi Papcr Millsj Ltd. disclose ll materials useful in their heat-respollsivc recordin~ papers.

il 11194()3 The live skin tissue imayiny method and apparatus just described, wherein electromagnetic energy is absorbed and con verted to image-producing quantities oE heat, require relatively large energy outputs from the source of radiant eneryy 10.
However, the risk of discomfort or damac~e to the live skin tissue¦
4 is mini~al because the heat is yenerated ~or only a short period of time, genexally a small fraction of a second~ Ho~Yever, where ¦
the available high power sources of radiant enercJ~ are consideredl too COSL1Y or to have too limited a life for the purposes in~olved r the other forms of the invention now to be described, where externally generated heat is applied to the substrates of the recording medium, would be used.

Reference should now be made to Fig. 2~ which illustrat/~..
one such form o~ the inventlon. ~s there shown,.the re~ording ., medium 2 is initially supported by spaced support members 18-18 ouk of contact with a source of external heat generall~ indicated¦
by reference numeral 19. As illustra~ed, thls source o~ ~xternal !
heat includes an outer heat storing neans 6'; which may ~e a 1:
body o~ metal. (This heat storing body consti.tutes what is sometimes referred to as an energy transmitting and contac~ memberl.
The heat storing body 6' is positioned upon a heAt insulatin3 body 20' made of a material having a very low`heat conductivity, like Teflon. The heat insulating body 20' covers the end face of a heated me~tal body 10', which is like a hot plate including resistance wire elements 23 coupled through s~itch means 21 to a voltage source 1~. The switch m-ans 21 is closed by control !l ~ 20 -.

~ 21 I
means 1~ t at various times to maintain the -t~mpera-ture oE t~e metal body 10' at a desired level. To -this end, a temperat~re-responsive element 22, which may be a thermocouple element or ~he like secured in or on the heated meta:l body 10', is connected to the control means 14l, which may be a conventional control circu;.tl~
which effects opening of the switch :means 21 when the ~emperature thereof rises above a given control level and closiny of th~
switch means 21 when the temperature of the me-tal body alls below a given control level ~generally slightly lower than the previous-ly mentioned control level).

The heat insulating body 20' allows heat -to pass rela--tivel~ slowly rom the heated metal body 10' -to the heat storlng body 6', which is given an appropriate thickness and volume to store an amount of heat at the control tempexature o~ the metal body 10' which will produce eEfective irnagin3 when the re~ording medium 2 is pressed by the live skin tissue involved against the outer face of the heat storing body. Wheh the recording medium 2 is pressed by the live skin tissue agains-t -the he~k storing body 6', as shown in Fiy. 2B, the heat stored ln this body rapidly passes into the substrate 2b of the recording med:i.u~ ~hose portions 14a, 14b and 14c (Fig. 2C) o~ the imagillcJ layer 2a oppo-site the recessed port.~ons ~a, 4b and 4c of the live skin tissue are raised to an imaging temperature, and those por-tions l~d and 14e thereo~ contacted by the raised portions 4d and ~e o~ the li~e skin t.issue 4 are heat-sinked to keep the temperature thereof bclow ~n im~ging level. The heat insulatin4 body 20'~

I
I
~ 21 -~ g ~ 3 - 22 !
l allows passage of heat from the metal body 10' to the heat storingj ¦ body h' so slo~ly that insufficient additional heat will be trans!
¦~ mitted to the heat storing body and recording medium as the heat storing body is cooled ~y its contact with the rec~rding medium ¦ to cause discomfort or damage to the live skin tissue 4, even if 1-i such tissue is held for many seconds against the heat storing ¦I body 6'.

¦! l ¦ Since it is desirable to reduce the risk of discomfort or damage to the live skin tissue 4 to a minimum, it is preferred to ¦
~ il modify the apparatus shown in Fig. 2A in the manner illustrated ; !1 in ~igs. 3A, 3B and 3C to which reference should no~7 be made. 'I
~; ¦j Also, the latter figures show as the recording me~ium a recording ¦
film 2' different from the recording medium previously described, in that the substrate 2b' thereo~ is optically tr~nsparent like, for example, the substrate of the dispersion-type recordi~g films disclosed in our co-pending application Serial No. 332,467. Also, the imaging layer 2a' of the recording film 2' may be a dispersion~
type imaging material like that disclosed in said application, so I
that when heat is transmitted through the substrate 2b' -to unheat-;
sinked portions of the imaging layer 2a' the same will be converte~ 1 from an initial opa~ue film to a transparent film thereat. The resulting transparency produced is desirable from the standpoint that it has an indefinite life under normal storage conditions and it can be readily projected in ~reatly enlarged form on a project-ion s ~een using conventional transparency projeotion equipment.

. I I
Il q - ---. =__ '` ~ lllg403 , .
The imaging apparatus.shown in Figs. 3~, 3B and 3C
utilizes a heak storing member 6I which is spring mounted to urge the same in outwaxcl spaced relatlonship -to a stop shoulder 25, While the sprln~ means which suppo.rts thc heat storing member 6' can take any variety of forms, it is illustrated as beincJ a coil spring 8. When the recording film 2' is depressed by the live skin tissue ~ against the heat s-toring rnember 6' with suf~icient pressure to form opti.mum heat-sinking of the recording film, the heat storing member 6' is depressed ~o a degree where it contacts the stop shoulder 25 which limits its further inward movement.
When the heat storing member 6' reaches the stop shoul~er 25l, the outwardly spring-urged sensing member ll'of a position s~nsing means 12 is depressed ~o efec-k VariQuS operations -to be described.
.~ . , .
Initially, even before the hea-t storing member ~' is depressed, the bottom .face thereof is contacted by the ouker ace of a heat applying plunger 24" connected to the arma-ture ~8a of a solenoid 28. The plunger.has an outer layer 20`' oE h~ak i.nsulating material which performs the same function as the heat insu:Latinc3 body 20' previously described. The heat insulaking layer ~0" ~orms ~ cover ing for the end of the main metal body 10" of the plunger 2~"
which has resistance wire elements 23" therein connected through switch means 21 to voltage source 16. Control means 14' may be the same a.s conventional. control circuit 1~' oE Fig. 2,controlled by a temperature-responsive element 22" l:ike a thermocouple shown embedded within the meta:l plunger bod~ 10". The -thermocouple 22"
is connected to control means 1~' which operates switch 21 con-t-olling the '~eding of volta-e sour~e 16 to the resistance wire .. , I . ' ' ( ' ' ~ 4 - 23 - :

.,~' 11, .

- 2~ ~
I 1.

elements 23" in -the same manner as in -the imaying apparatus of jl Figs. 3A, 3B and 3C.

- ~ The bottom face of -the plunger 2~" i5 sho~n mo~-t~ on ~F~ j the coil spring 30 extending between sta-tionary shoulder~; 31-31 ,-. ¦ and the bot-tom of the plunger ~4". The coil spring 30 no.~ lly C ~j~resiliently urges the outer face of the ~lung~r constituted by thej : I outer face of the heat insulating layer 20" into contact w.~h the ¦
bottom face of -the heat storiny memher 6'. As previousl~ ~ted ¦I the coil spring 30 also urges the hea-t storing member 6i in~ a : ll position elevated from the stop shoulder ~5. rl'he bottom of the plunger 24" is connected to the outwardly spring~urged arma-~e 28a of a solenoid 28. Before the solenoid 2a is energized, ~en ~ the recor~ing film ~' is pressed by the l.ive skin tissue aga~nst ¦ the heat storing member 6' with adequate pressure for effect~ng .. i good heat-sinking of the recording film 2 (Fig. 3B~, the resultin~
. : movement of the heat s~oring member 6' ayainst the stop sho~lder ~: ~ 25 also depresses the outwardly spring-ur~ed armature 2~a o~ the ~. ¦ solenoid 28 correspondingly. When the solenoid 2a is energn.~ed .n:a manner now to be described, th~ armature 26a.o t~e.so~enoid 28 will be further drawn into the solenoid 28 to withdraw ~
plunger 2~" from contact with the still depressed heat sto~g . I member 6' as shown in Fig. 3C,so that the member 6' w.ill ~
receive an~ appreciable heat from the plunger to remove a~ risk . of causing discomfort or damage to the live skin tissue ~
~~

~ 2~ - I
. i ~
-: I ' ' . '

3 _~5 ¦I Wheil the position scnsirlc~ means 12' ;s operatcd ~IS pre-viousl~ described upon depression of -the heat storing member 6', ¦ i-t closes normally-open switch means 34 and 42 Switch me~ns 42 connects ground to a timer 40 to initiate the operation thereof ¦I which closes normally-open switch means 36 a ~ivcn time period after the switch means 42 closes, which may be a peri~d, for ¦ example o:E substantially less than one second (c~g~ 0~1 seconds~:
i Closure of the s~itch means 34 and 36 couples a sou~ce of voltage 38 to the solenoid 28 to energize the same so it withdraws the plunyer 24'' from contac-t with the bottom face of the heat storing member 6 O

l When the pressure o the live skin tissue 4 on -the recorci ing film 2' is relieved, the return of the outwardly spring-urged member 11 of the position sensing means 12' to its initial posi-. tion allo~s switch means 34 and ~2 to re-open to reset and de-. energize ~he timer 40 and to de-energize solenoid 28 -to ~ring the plunger 24'' agains into contact with the bottom face oE-the heàt ~¦ storing member 6l. .
I , . ' '- ' .
. Refer now to Fig~ 4 which shows a different form of the invention having a heated metal body in the form of a ribbon~ e resistance element lOa'' on a body 20a'l of heat insula-ting mater~.
spring-mounted on coil spring 30.

The ribbon-like resistance elemen-t lOa " of the plunger 24a'' is connected between ground and voltage~source 16 through normally-opened switch mearls 46 and normally-closed switch means 44. Switch means 44 is opened by a timer 40' a gi~en time period after the ~.imer is rendered operative by closure oE switch means 42'. Switch means 42' and 4~ are closed by position sensing mean ;

_...... . . I!.. ~..... ... . . ...... . ...... .

`'` ' I lllg4~3 ' I
ll - 26 . I I
12' when the hea-~ storing rnember 6' is dep.ressed against tht~ stop shoulder 25. The voltage source 16 is thus ~oupled to the r.~bon-like resistance element lOa 1l when the heat storiny member 6' .~.s pressed against the stop shoulder 25, and is de-eneryized ~ gl~en I
predetermined time period later when the timer 40' opens switch 1 means 44. The ribbon-like resistance element lOa" is ~hus pulsed I
with a current (which may be a pulse of about 1 seconds or less), ¦
which produces sufficient heat energy in the rib~on-like resistance element lOa" to produce good imaging o~ the unheat-sinked portions of the recordin~ .film 2' pressed thereagainst. The body of heat insulatiny material 20a" constituting the plunger body prevents siynificant heat loss from the ribbon-like.resistance element lOa' except in the direction o~ the heat storin~ memher 6'. I

When the pressure on the heat storing member 6' is reliev ed, switch means 42' and 46 re-open to de-energize and reset the timer 40' and ~to de-energize the ribbon-like resistance element lOa". As in the case of the ernbodiment of the invention shown in Fig. 1~ using a source oE pulsed radian-t energy, the form of the invention now being descrlbed does not offer a substan-tlal risk of discomfort or damage to the live skin tissue i~volvecl because the source of heat, namely the ribbon-like res.istance element lOa" !
i5 only momentarily eneryiæed. However h if one de.sired to reduce ¦
the risk o~ discomfort or damaye to the live skin tissue involved, one çould connect the body 20a" of heat insulatiny material with the ribbon-like resistance element lOa" thereon to -the armature fl solenoid 28 which would be operated in the manner previously des- ¦
~cribed so th the rlb~o~-like rss~stsnce element 10 Q" is with-'l Il - 26 -, dra~n from contact with the heat storing ~ember 6' imm~diate3y ¦l after completion o~ an imaging operation. In such case, any un-dissipated heat remaininy in the ribbon-li]ce resistance element lOa" after termination of current flow therethrou~h will not be transmitted to the he~t ~tori~g n~mber 6' o~ the recording medium -Perhaps one of the rnost important applications of the li present invention is in an apparatus for recording and ~he apply-! ing a fingerprint to the rear of a check. Fig. 5A illustrates the basic components o~ a preferred form of such an appar~-tus. Where the resolu-tion requirements of the recorded image is not unduly ~ great and archival properties of the recorded image are not needed ¦¦as is the case in a fingexprint check security system~ the record-j ¦1 ing medium 2" may be a low cost thermally-responsive recording jlpaper. In ~ig. 5A, a strip of such recording paper is s~own wound I lupon a supply reel 48. The strip 2" of recording paper is unwound I Ifrom the supply reel 48 and passed over aild around guide rollers 50, 52, 54, 56, 58 and 60 where it is then attached to a take-up reel 62. As shown in Fig. SB, the strip o~ recording paper con- ¦
- tains on one~ face thereof, for example, over the imaging layier 2a"1 thereo~, an optically transparellt coating 2c" of a release material which will no-t stic~ to pressure sensitive adhesive materials. A
jcoating 2d" of pressure sensiLive adhesive material is applied r ~ ` ¦over the paper substrate 2b" thereo~. I-t is thus apparent that the layers of the strip 2" of recording material when wound on the reels 48 and 62 will not stick together -to interfer with the free unwinding thereof.
1!

3 Il . I
I
As illustratecl in Fig. 5A, -the portion of the s-trip of recording paper extending bet~een rollers 52 and 5~ pass over spaced member 18-18 at a recording station 1' like that shown in Fi~s. 3A, 3B and 3C. Accordingly, there is providecl a-t this recording station 1I the aforementioned heat storage member 6', plunger 24", solenoid 28, position sensiny means 12' and a control circuit 63 which may include the various control circuit elements shown in Figs. 3A, 3B and 3C. The control circuit 63 con-trols the energization of an elec-trical mo-tor 61 which, when ener~ized, rotates the take-up reel 62 in a direc-tion to unwind the strip of i recording material fur-ther than the suppl~ reel 48. The control circuit 63 also controls the energization of an electrical motor 65 having a function to be described. Additionally, thexe is shown at the control station 1' a micro-switch 12 having a posi- , tion sensing arm 12a whi.ch is depressed to operate the micro- ¦
s~itch 12 ~n el man~er Oo be cle,crlb.d.

~, '' 11 . ' " ' ' ''..'" j ' ' ' ' ,' . I
~; . .
I
. . I

., ~

li - 2~
~1 I

9~03 - 29 ¦I Fig. 5A shows the strip ~" of recordin~ paper passing beneath spaced guide rollers 5~ and 56 at a check-receivhnt~ ¦
I s-tation 55 having a check-receiving platform 57 in space~ ~elation-¦¦ ship beneath the strip of recording material - Supported~above the strip of recording material at the check-receiving station 55 is a plunger body 68 secured for down-ward movement to the armature 70a of a solenoid 7Q ~ 0se en~rgi-¦¦ zation is controlled'by the control circuit 63. The plunger body68'has a film-severing rim portion 66 which,when the plunger ~8 . pressed against the strip of recording materi~l,will sever the . ¦ portion of the recording film on which a fin~erprint had been pre-I : ¦ viously produced at the recording station l'. The por-tion o~ the ' strip of ecording material'severed from the rest o~ the strip .
will not destroy the integr:ity o~ the remainder of the strip . which will ultimately.be wound upon the take-up reel In the ; process of the downward movement of the plunger body 68 r the ~ bottom face thereof will press the severed fingerprint-contaiJLing I
: .. ¦ cutout from the strip upon the backside of ~he check which ha~ been ;~ . . ¦ previously placed upon the~check-recelvlng plat~orm 57. .' '' : . The check placed upon the platform 57 is moved benea~h a pair of rollers 72-72 which frictionally engage the check. The . rollers are'secured to a comrnon shaEt 74, in turn, coupled t~ the : ~ ¦ shaft of the motor 65 so khat when the motor 6~ is energize~ rota-: tion of the rollers 72-72 will eject the check,to which a f'in~er- ¦
. print containing recording paper cutout had been just previously applied by the plunger body 68, from ~ht~ platform S7.

. I . ' .
1~ ' '' ' .
- 29 ~ ' ': , I
. I '. _ 9~)3 Il - 30 ¦~ Thc operation of the apparatus shown in I~'ig. r~ as , controlled by ~le'control circuit 63 is as follows: Pirst of all . the fingerprint imaye is formed at the recording station in the same Manner as described previously in connection with the i! description of Figs. 3~, 3B and 3C, asa person presses his ¦¦ finger against the strip of recording material at the recording ¦I station 1' to briny the same against the heat storing member 6' with suEficient force to press the heat storing mel~er 6' against li the stop shoulder 25. When the spring arm 12a of the micro-switc~

i1 12 is depressecl to a lowermost position unaer the circumstances : . j, .
when the solenoid 28 is energized to withdraw the plunger 24'' from contact with the heat storing memher 6:', the micro-switch 12 operates -to~ prapare the control circuit 63 for a xecording paper advancing operation when the user releases pressure on the ¦ strip ~f 'recording material;sensed by the reLurn o:E the upwardly ¦ spring-urg'ed membexll! of the position sensin~ means 12' to its initial uppermost position.- When this occurs, the con~rol circuit 63 feeds a ~urst of energizin9 current to the motor. 61 .
¦ coupled to the take-up'reel 62 to bring the por-tion of the strip : ¦ 2'' of recording material just imaged at the recording station 1' , to~a~position at the check-receiving,station 55 centered between the rollers 54 and 56 thereo~. The contxol circuit 63 then I . momentarily energizes the solenoid 70'to bring the pluncJer body 68 momenkarily downwardly to sever the previously recorded , . .. fingerprin-t from,the strip 2'' and appl~ thé recording paper : C ......... cut--out to the check on the platform 57 where the pressure ¦ sensitive adhe~sive on the bo-ttom thereof adheres it permane'ntly , . j to the check. The con,txol circuit 63 then momentarily energizes ¦
¦I the electrical motor 65 to cause the check-feeding rollers 72-72 ¦

¦I to feed the check to a withdrawal slot (not shown) where the ¦l chec~ can be withdrawn rrom the housing of the apparatus shown.

I, il ' - 30 - :
~ 11 ~ 9~3 -. 31 ¦ The vari.ous forms of the inven-tion have thus pxovided immediately available surface topology records of live skin ¦l tissue without the use of inks or chemicals and in a manner which ¦ minimizes.risk of discomEort or damage to the livè skin tissue Il ' .
¦ While the forms of the invention described are the ¦¦ pre~erred ones under the various conditions described, it should !i be apparent that numerous modifications may be m~de therein without deviat.ing from the broader aspects thereof. For cxample, in the embodiment of the invention shown in Fig. 5A the s-trip ¦ feeding and/or strip severing operatio~s could be carried out ¦ mechanically by manual operation of lever members or the like .
¦ LatheI than by automatically contro1led electr}cal motors.

1 - ~

- ~

Claims (30)

WE CLAIM: - 32

1. A method of recording the surface topology of live skin tissue comprising the steps of: providing a recording medium having a substrate upon one side of which there is a layer of a heat-responsive-imaging material which, upon conduction of a given amount of heat energy to any given portion thereof will be heated to a given imaging temperature in the absence of any substantial heat-sinking applied to said one side of the recording medium;
applying said live skin tissue against the imaging layer contain-ing side of the recording medium so that projecting portions of the live skin tissue act as effective heat-sinks at the points where it is most contiguous thereto to dissipate heat thereat to an extent where said imaging material is not imaged appreciably, if at all, by said amount of heat energy conducted to the portion of said imaging material involved from said substrate and wherein the heat-sinking effect of the live skin tissue where recessed portions thereof are located is so minimal as not to prevent said given amount of heat energy from raising the temperature of the portion of the recording medium involved to said imaging tempera-ture; and then applying a pulse of energy to the substrate side of said recording medium which will provide heat energy in said sub-strate which is conducted in at least said given amount to each of the various portions of said layer of imaging material, said pulse of energy being applied to said substrate side of said record ing medium only while said live skin tissue is in contact with said recording medium.

2. The method of claim 1 wherein said energy applied to said substrate side of said recording medium is electromagnetic energy which is absorbed in the substrate of said recording medium to a degree to provide sufficient heat to effect conduction of said given amount of heat energy to each of said various portions of said layer of imaging material of the recording medium.

3. The method of claim 1 wherein said energy applied to the substrate side of the recording medium is heat energy con-ducted to the substrate of the recording medium.

4. The method of claim 3 wherein said heat energy is applied by a body whose temperature is maintained at a given controlled temperature; there is positioned between said body and the substrate side a heat storing member which is initially conti-guous to said temperature controlled body where it stores therein sufficient heat energy to produce said given amount of heat energy conducted to said various portions of the layer of imaging mater-ial of said recording medium when brought into contiguous relation-ship thereto, the imaging of said recording medium being effected by pressing said live skin tissue against the imaging layer-containing side of said recording medium to press the substrate side thereof upon said heat storing member; and following the imagine of said recording medium withdrawing said temperature con-trolled body from its position contiguous to a heat storing member to prevent discomfort or damage to said live skin tissue is held for a prolonged period in its position pressing the recording medium against said heat storing member.

5. The method of claim 4 wherein there is positioned between said temperature-controlled body and said heat storing member a material of relatively low heat conductivity so that when the heat stored in said heat storage member passes into said recording medium the heat storing member will receive heat only slowly from said temperature-controlled body while positioned contiguous to said body.

6. A recording system for recording the surface topology of live skin tissue, said recording system comprising: an energy transmitting and contact member spring mounted for a given pre-determined inward movement when a given inward pressure is applied thereto; a heat imageable recording medium supported in confront-ing relation to one side of said energy transmitting and contact member, which recording medium is to be brought into contact with said energy transmitting and contact member to depress the same when an image of said live skin tissue is to be made, said record-ing medium comprising a substrate facing said member and upon the outer side of which there is a layer of a heat-responsive imaging material exposed to be engaged by said live skin tissue, and which upon conduction of a given amount of heat energy to any given portion thereof, will be heated to a given imaging temperature in the absence of any substantial heat-sinking applied to said outer side of the recording medium; energy applying means for applying energy to said heat transmitting and contact member which energy is transmitted to the substrate of said recording medium to pro-vide heat energy therein in sufficient amounts to effect conduct-ion of at least said given amount of heat energy to each of the various portions of said layer of imaging material of the record-ing medium, to provide selective imaging of unheat-sinked or minimally heat-sinked portions of said layer of imaging material;
and means responsive to a given movement of said energy trans-mitting and contact member for applying said energy to said member for a predetermined period.

7. The recording system of claim 6 wherein said energy applied by said energy applying means to said energy transmitting and contact member is electromagnetic energy which is absorbed in the substrate of said recording medium to a degree to provide sufficient heat to effect conduction of said given amount of heat energy to each of said various portions of said layer of imaging material of the recording medium.

8. The recording system of claim 6 wherein said energy applied by said energy applying means to said energy transmitting and contact member is heat energy conducted to the substrate of the recording medium.

9. The recording system of claim 8 wherein said energy applying means includes a body to be heated to a given temperature said energy transmitting and contact member while in contiguous relation to said body to be heated receives sufficient heat energy to transmit said given amount of heat energy to said various por-tions of the layer of imaging material of said recording medium bought into contiguous relation thereto; and there is provided means following the imaging of said recording medium for withdraw-(Claim 9 continued) ing said body to be heated from a position contiguous to said energy transmitting and contact member to prevent discomfort or damage to said live skin tissue if held for a prolong period in this position pressing the recording medium against said energy transmitting and contact member.

10. A recording system for recording the surface topolog of live skin tissue, said recording system comprising: an energy transmitting and contact member; a heat imageable recording medium supported in confronting relation to one side of said energy trans mitting and contact member, which recording medium is brought into contact with said energy transmitting and contact member to depres the same when an image of said live skin tissue is to be made, said recording medium comprising a substrate facing said member and upon the outer side of which there is a layer of a heat-responsive imaging material exposed to be engaged by said live skin tissue and which, upon conduction of a given amount of heat energy to any given portion thereof, will be heated to a given imaging tempera-ture in the absence of any substantial heat-sinking applied to said one side of the recording medium; energy applying means for applying energy to said heat transmitting and contact member which is transmitted to the substrate of said recording medium to pro-vide heat energy therein in sufficient amounts to effect conductio of at least said given amount of heat energy to each of the variou portions of said layer of imaging material of the recording medium (Claim 10 continued) to provide selective imaging of unheat-sinked or minimally heat-sinked portions of said layer of imaging material, said energy applying means including a body to be heated to a given tempera-ture; said energy transmitting and contact member being a heat storing member which is initially contiguous to said body to be heated and stores sufficient heat energy to transmit said given amount of heat energy to said various portions of the layer of imaging material of said recording medium when the recording medium is brought into contiguous relation thereto; and there is positioned between said body to be heated and said heat storing member a material of relatively low heat conductivity, so that when the heat stored in said heat storing member passes into said recording medium the heat storing member will receive heat only slowly from said body to be heated while remaining contiguous thereto

11. A recording system for recording the surface topology of live skin tissue, said recording system comprising: an energy transmitting and contact member against which a heat imageable recording medium is to be pressed by said live skin tissue, said recording medium to include a substrate upon the outer side of which there is a layer of a heat-responsive-imaging material exposed so as to be engaged by said live skin tissue and which, upon conduction of a given amount of heat energy to any given portion thereof, will be heated to a given imaging temperature in the absence of any substantial heat-sinking applied to the outer side of the recording medium; heat applying means for applying energy to said heat transmitting and contact member which energy is transmitted to the substrate of said recording medium in suffi-cient amounts to effect conduction of at least said given amount of heat energy to the various portions of said layer of imaging material thereof, to provide selective imaging of unheat-sinked or minimally heat-sinked portions of said layer of imaging mater-ial, said heat applying means including a body whose temperature is to be heated to a given temperature; said energy transmitting and contact member being a heat storing member which is at least initially contiguous to said body to be heated where it stores therein sufficient heat energy to produce said given amount of heat energy conducted to said various portions of the layer of imaging material of said recording medium brought into contiguous relation thereto; and means following the imaging of said record-ing medium for withdrawing said body to be heated from its position contiguous to said energy transmitting and contact member to prevent discomfort or damage to said live skin tissue if held for a pro-longed period in its position pressing the recording medium agains said member.

12, The recording system of claim 11 wherein said body to be heated is a member which has a resistance element in the same, and said heat applying means includes means for feeding heating current to said resistance element for a fixed predeter-mined amount of time when said recording medium is pressed by the live skin tissue against said energy transmitting and contact member.

13. The recording system of claim 11 wherein said body to be heated is a member which is kept at a given temperature.

14. The recording system of claim 13 wherein there is positioned between said body to be heated and said energy trans-mitting and contact member a material of relatively low heat con-ductivity, so that when the heat stored in said member passes into said recording medium the energy transmitting and control member .
will receive heat only slowly from said body to be heated while positioned contiguous to said body.

15. The recording system of claim 11 wherein said energy transmitting and contact member is spring-urged to an outer posi-tion and is adapted to move inwardly a given amount when a given pressure is applied thereto as a recording medium is pressed by the live skin tissue with a given predetermined force against said energy transmitting and contact member; and there is provided control means responsive to said given amount of movement of said energy transmitting and contact member for withdrawing said body to be heated from its position contiguous to said energy trans-mitting and contact member a given time period after said given amount of movement is imparted to said energy transmitting and contact member.

16. The recording system of claims 9 and 15 wherein said body to be heated is spring-urged to an outer position so as to be initially contacted with said energy transmitting and contact member before and after said member is moved inwardly by the force applied by the live skin tissue pressing the recording medium against said member.

17. Apparatus for recording the surface topology of live skin tissue, said apparatus comprising: a recording station and a recording strip-severing station; a strip of imageable recording material extending by said recording and strip-severing stations, said strip of recording material having an imaging layer on one side thereof; said recording station including imaging means responsive to application of a given live skin tissue pressure to said strip of recording material by providing an image of the surface topology of the skin tissue applied thereto; means for automatically advancing the imaged portion of said strip of recording material to said strip-severing station when pressure on said strip of recording material is relieved; said strip-severing station including strip-severing means mounted for movement between an inoperative position and an operative position where the imaged portion of said strip of material is severed from the rest of the same; and means for operating said strip-severing means.

18. The apparatus of claim 17 wherein said means for operating said strip-severing means is operated automatically when an imaged portion of said strip of recording material is moved to said strip-severing station.

19. Apparatus for recording the surface topology of live skin tissue, said apparatus comprising: a recording station and a recording strip-severing station; a strip of imageable recording material extending by said recording and strip-severing stations and between take-up and supply reels, said strip of recording material having an imaging layer covered by an optically transparent exposed release material which will not adhere to a pressure sensitive adhesive material, and a pressure sensitive adhesive on the opposite side thereof; said recording station including imaging means which,upon application of live skin tissue to said imaging layer of said strip of recording material, provides an image of the surface topology thereof; means for momentarily rotating said supply reel to advance the imaged portion of said strip of recording material to said strip-severing station after a live skin tissue image is formed; said recording strip-severing station including a strip-severing means mounted for movement between an inoperative position and an operative position where the imaged portion of said strip of imageable recording material is severed from the rest of the same, the strip of imageable recording material from which the imaged portion thereof has been severed maintaining its integity to form a web of such material which is would upon said take-up reel;
and means for operating said strip-severing means.

20. The apparatus of claim 19 wherein said imaging means operates to provide said image when the live skin tissue pressure applied to said recording material reaches a given predetermined level.

21. The apparatus of claim 19 wherein said means for momentarily rotating said supply reel operates automatically when live skin tissue pressure is removed from said strip of recording material.

22. The apparatus of claims 19, 20 or 21 wherein said means for operating said strip-severing severing means operates automatically when the imaged portion of said strip of recording material reaches said strip-severing station.

23. Apparatus for recording a fingerprint and applying the same to a check or the like, said apparatus comprising: a fingerprint recording station and a check-receiving station; a strip of heat-imageable recording material initially wound on a supply reel and extending therefrom passed said finger-print recording and check-receiving stations and then extending upon a take-up reel, said recording material having a substrate upon which is coated a heat-responsive imaging layer, an exposed layer of pressure sensitive adhesive material on said substrate, and an exposed optically transparent exposed release material on said imaging layer; said fingerprint recording station including imaging means responsive to the application of a given finger pressure to said heat-responsive imaging layer of said strip of heat imageable recording material for providing an image of the surface topology of the skin tissue applied thereto and for automatically advancing the imaged portion of said strip of heat imageable recording material to said check-receiving station when pressure on said strip of material is relieved; said check-receiving station including a strip-severing and recording material applying means mounted for movement between an inopera-tive position and an operative position where the fingerprint imaged portion of said strip of material is severed from the rest of the same and applied to a check at said check-receiving station, the strip of heat imageable recording material from which the fingerprint portion thereof has been severed maintaining its integity to form a web of such material which is wound upon said take-up reel; and means for operating said strip-severing and recording material applying means.

24. The apparatus of claims 17, 19 or 23 wherein said imaging layer is made of a heat-imageable material which, upon conduction of a given amount of heat energy to any given portion thereof, will be heated to a given imaging temperature in the absence of any substantial heat-sinking applied thereto; and said imaging means including: an energy transmitting and contact member confronting the inner side of said strip of recording material and spring mounted for a given predetermined inward movement when a given inward pressure is applied thereto, energy applying means for generating energy to be applied to said heat transmitting and contact member which energy is transmitted therefrom to said strip of recording material to provide said given amount of heat energy to each of the various portions of said layer of imaging material, to provide selective imaging of unheat-sinked or minimally heat-sinked portions of said layer of imaging material, and means responsive to a given movement of said energy transmitting and contact member for applying said energy to said member only for a predetermined period.

25. The apparatus of claims 17, 19 or 23 wherein said imaging layer is made of a heat-imageable material which, upon conduction of a given amount of heat energy to any given portion thereof, will be heated to a given imaging temperature in the absence of any substantial heat-sinking applied thereto; and said imaging means including: an energy transmitting and contact member confronting the inner side of said strip of recording material and spring mounted for a given predetermined inward movement when a given inward pressure is applied thereto, energy applying means for generating heat energy to be applied to said heat transmitting and contact member which energy is transmitted therefrom to said strip of recording material to provide said given amount of heat energy to each of the various portions of said layer of imaging material, to provide selective imaging of unheat-sinked or minimally heat-sinked portions of said layer of imaging material, and means responsive to said given movement of said energy transmitting and contact member for applying said energy to said member only for a predetermined period.

26. The apparatus of claims 17, 19 or 23 wherein said imaging layer is made of a heat-imageable material which, upon conduction of a given amount of heat energy to any given portion thereof, will be heated to a given imaging temperature in the absence of any substantial heat-sinking applied thereto;
and said imaging means including: an energy transmitting and contact member confronting the inner side of said strip of recording material and spring mounted for a given predetermined inward movement when a given inward pressure is applied thereto, energy applying means for applying heat energy to said heat transmitting and contact member which energy is transmitted to said strip of recording material to provide said given amount of heat energy to each of the various portions of said layer of imaging material, to provide selective imaging of unheat-sinked or minimally heat-sinked portions of said layer of imaging material, said energy applying means including a body to be heated to a given temperature, said energy transmitting and contact member while in contiguous relation to said body to be heated receiving sufficient heat energy to transmit said given amount of heat energy to said various portions of the layer of imaging material of said strip recording material brought into contiguous relation thereto, and means following the imaging of said strip of recording material for withdrawing said body to be heated from a position contiguous to said energy transmitting and contact member, to prevent discomfort or damage to said live skin tissue if held for a prolonged period in this position press the strip of recording material against said energy transmitting and contact member.

27. The apparatus of claims 17, 19 or 23 wherein said imaging layer is made of a heat-imageable material which upon conduction of a given amount of heat energy to any given portion thereof, will be heated to a given imaging temperature in the absence of any substantial heat-sinking applied thereto;
and said imaging means comprises: an energy confronting the inner side of said strip of recording material energy applying means for applying heat energy to said heat transmitting and contact member which is transmitted to the strip of recording material to provide at least said given amount of heat energy to each of the various portions of said layer of imaging material to provide selective imaging of unheat-sinked or minimally heat-sinked portions thereof, said energy applying means including a body to be heated to a given temperature; said energy transmitting and contact member being a heat storing member which is initially contiguous to said body to be heated and stores sufficient heat energy to transmit said given amount of heat energy to said various portions of the imaging layer when the strip of recording material is brought into contiguous relation thereto; and a material of relatively low heat conductivity positioned between said body to be heated and heat storing member, so that when the heat stored in said heat storing member passes into said strip of recording material the heat storing member will receive heat only slowly from said body to be heated while remaining contiguous thereto.

28. The apparatus of claims 17, 19 or 23 wherein said imaging layer is made of a heat imageable material which, upon conduction of a given amount of heat energy to any given portion thereof, will be heated to a given imaging temperature in the absence of any substantial heat-sinking applied thereto; ans said imaging means comprises: an energy transmitting and contact member confronting the inner side of said strip of recording material heat applying means for applying energy to said heat transmitting and contact member which energy is transmitted to the strip of recording material which brought into contact therewith to provide at least said given amount of heat energy to the various portions of said imaging layer, to provide selective imaging of unheat-sinked or minimally heat-sinked portions of said layer of imaging material, said heat applying means including a body whose temperature is to be heated to a given temperature, said energy transmitting and contact member being a heat storing member which is at least initially contiguous to said body to be heated where it stores therein sufficient heat energy to produce said given amount of heat energy conducted to said various portions of the imaging layer brought into contiguous relation thereto, and means following the imaging of said strip of recording material for withdrawing said body to be heated from its position position to said energy transmitting and contact member to prevent discomfort or damage to the finger member if held for a prolonged period in its position pressing the strip of recording material against said member.

29. The method of any of claims 1, 2 or 3 wherein the duration of said pulse of energy is substantially less than one second.

30. The method of any of claims 4 or 5 wherein the duration of said pulse of energy is substantially less than one second.