CA1297177C - Graphics input tablet - Google Patents
Graphics input tabletInfo
- Publication number
- CA1297177C CA1297177C CA000564186A CA564186A CA1297177C CA 1297177 C CA1297177 C CA 1297177C CA 000564186 A CA000564186 A CA 000564186A CA 564186 A CA564186 A CA 564186A CA 1297177 C CA1297177 C CA 1297177C
- Authority
- CA
- Canada
- Prior art keywords
- conductors
- graphics input
- tablet
- input tablet
- resistive layer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
- G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
- G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
- G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
- G06F3/045—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact
Abstract
ABSTRACT
GRAPHICS INPUT TABLET
A graphics input tablet has a conductive layer and a resistive layer with contacts (16,17,23,24) arranged one along each edge of the resistive layer. The conductive layer is held at a negative potential relative to the resistive layer so current flows in each contact when localised pressure is applied to a region of the tablet (20) to bring the layers into electrical contact. The currents vary with both posi-tion and magnitude of the localised pressure. The position of the pressure is detected from the relative currents in opposed contacts and the magnitude of the pressure is detected from the total current in the contacts. The currents are measured by current sense amplifiers and processed in a computer. Analogue front-end processing of the currents is also possible.
GRAPHICS INPUT TABLET
A graphics input tablet has a conductive layer and a resistive layer with contacts (16,17,23,24) arranged one along each edge of the resistive layer. The conductive layer is held at a negative potential relative to the resistive layer so current flows in each contact when localised pressure is applied to a region of the tablet (20) to bring the layers into electrical contact. The currents vary with both posi-tion and magnitude of the localised pressure. The position of the pressure is detected from the relative currents in opposed contacts and the magnitude of the pressure is detected from the total current in the contacts. The currents are measured by current sense amplifiers and processed in a computer. Analogue front-end processing of the currents is also possible.
Description
~97~77 GRAPHICS INPUT TABLET
Description Introduction This invention relates to a graphics input tablet. The invention is particularly useiul in the data processing field where it may be employed to input data of a graphical nature into a data processing machine.
Back~round Art In the data processing field one of the major problems to users of a system is the rapid inputting of data. This has traditionally been achieved with a keyboard but when it is necessary to input graphical data, rather than character strings, a keyboard is grossly inefficient.
There are various examples in the prior art of attempts to provide a more efficient and easier to use input means for graphical data.
One such example is disclosed in EP 5,996 (Quest Automation Ltd.) which shows an electrographic apparatus with two resistive layers, one overlying th~ other, held apart by a framework but arranged to be brought into contact by the pressure of a stylus or similar. Excitation voltages are applied to the resistlvs layer at 90 degrees to each other and two analogue voltages related to the position of the stylus are obtained in an unspecified manner.
Another example is disclosed in GB 2,088,063 (Robert Branton).
This shows a conductive layer overlying a rectangular resistive layer with an insulating mesh between the two. The resistive layer has a contact at each corner and one opposed pair of contacts ls energised at any one time. A stylus (ball-point pen or similar) is pressed onto the upper, conductive layer which then makes contact, through a gap in the insulating mesh, with the resistive layer. In consequence, the poten-. ~ . , ~Z5~7~77 tial of the conductive layer equals that of the resistive layer at the point of contact; since this varies with the relative distances of the point from each of the polarised contacts, the potential of the conduc-tive layer provides information to identify the position of the stylus.
Once the position with respect to these polarised contacts is estab-lished they are de-energised and the other pair is polarised to give information regarding the position of the stylus along a different axis. Thus the position of the stylus in 2 dimensions may be identi-fied.
Summar~ of_the Invention The prior art techniques only permit 2 dimensional input directly from the tablet; if a third dimension is required it must be input by other means eg a potentiometer arran~ed for manual control. The ability to input 3 dimensional data using the tablet alone would be very useful, for example a) to define the colour and/or intensity of a location on a graphic terminal or b) for signature verification where the profile of the pressure applied across the signature would be a useful additional check, above and beyond a 2 dimensional check of the appearance of the signature. Further, the prior art techniques do not permit the pressure information to be detected at all; this information could be useful, for example in the case of a one dimensional position-detecting tablet in the form of a strip. This would provide 2 dimen-sional input capability without occupying the large area taken up by a prior art 2-d input tablet.
Accordingly, the present invention provides a graphics input tablet comprising a layer of electrically resistive material supported co-extensively with a layer of electrically conductive material to provide a flat tabl0t surface, the resistive material having the property that the electrical resistance between the layers in the region of localised pressure applied thereto changes monotonically with the applied pressure, first and second conductors connected respective-ly to first and second portions of the resistive layer said portions ., 7~
being spaced apart on a first notional line across the tablet surface, the construction and arrangement being such that with an electrical potential applied between the resistive layer and the conductive layer substantially no current flows through said first and second conduc-tors, but with said localised pressure applied to said tablet surface currents flow through said first and second conductors, the relative magnitudes of the currents being related to the respective distances of the region of applied pressure from the first and second portions and the total current flowing between the resistive sheet and the conduc-tive sheet being related to the magnitude of the applied pressure.
! This provides the facility to detect the position of a stylus in two dimensions, ie one linear dimension and one pressure dimension.
Preferably, the graphics input tablet further comprises third and fourth conductors connected respectively to third and fourth portions of the resistive layer9 said portions being spaced apart on a second notional line, intersecting said first notional line, across the tablet surface, such that when said localised pressure is applied in said region currents flow in said third and fourth conductors9 the relative magnitudes of the currents in the third and fourth conductors being related to the respective distances of said third and fourth portions from the area of applied localised pressure.
This provides the facility to detect the position of a stylus in 3 dimensions, ie two linear dimensions and one pressure dimension.
Preferably, the graphics input tablet has electrical sensing means arranged to evaluate said total current by summing the individual currents measured in each of said conductors.
Alternatively, the graphics input tablet has electrical sensing means arranged to evaluate said total current from a measurement of the current flowing between the electrical excitation means and the conduc-tive layer.
, . ~ . ... .
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The resistive layer may be in the form of a single sheet of material. Alternatively, the resistive layer may comprise two sheets, each of a resistive material, the conductors being connected to a first of said sheets and the second of said sheets having the property as aforesaid that the electrical resistance between the layers in the region of localised pressure applied thereto changas monotonically with the magnitude of the pressure applied to the layers.
Description of the Drawings Figure la shows schematically a cross-section through a graphics lnput tablet according to the present invention.
Figure lb shows schematically a cross-section through an alterna-tive embodiment of a graphics input tablet according to the present invention.
Pigure 2 shows schematically a plan view of the tablet of fig la.
Fig 3a shows schematically a circuit for processing signals representing positional and pressure information produced by the present invention.
Fig 3b shows schematically a circuit for inputting the outputs of the circuit of fig 3a into a computer.
Fig 4 shows schematically an alternative circuit for processing signals representing positional and pressure information produced by the present invention and inputting this into a computer.
Fig S is a schematic graph showing variations in positional measurements versus actual position when employing the present inven-tion.
~'71~
Fig 6 is a schematic graph showing variations in measured total current versus actual force applied to a small area using the present invention.
Detailed Description of the Invention Fig la shows a graphics input tablet according to the present invention. Layer 10 is a compressible resistive sheet known as Verma-hide (Trade Mark). This material has the property that its localised electrical resistance reduces with increased pressure exerted on it as the electrically conducting fibres which make it up are forced into more intimate contact. Beneath layer 10 is layer 11 which is an elec-trically conducting coat applied to insulating substrate 13. Beneath insulating substrate 13 is conductive coat 50 which may be electrically grounded to give electrostatic screening. Layers 11,13,50 may con-veniently be provided by double-sided unetched printed circuit board.
Overlying layers 10,11,13,50 is protective sheet 12 which is electri-cally insulating, physically hard-wearing and yet locally elastically deformable. Electrical connection is made to conductive layer 11 by conductor 30 and to opposed edges of resist~ve layer 10 by conductors 14,15,21,22 (see fig Z).
FiB lb shows an alternative tablet comprising two resistive sheets, one compressible 10a and one rigid 10b. Conductive layer 11 overlies the resistive sheets and is locally elastically deformable.
Fig 2 shows a plan view of the tablet in fig la. Contact pads 16,17,23,24 are shown, attached to conductors 14,15,21,22 respectively.
Each contact pad makes electrical contact with a portion of the resis-tive layer: 16,17,23,24 contacting 18,19,25,26 respectively. This leaves the remainder 20 of layer 10 as the input region where a user applies localised pressure with a stylus, causing currents to flow in conductors 14,15,21,22.
Fig 3a shows one technique for producing signals x,y,z represent-i~ . .~, .. .
lZ97177 ing the position of pressure applied on region 20 (x,y) and the magni-tude o~ pressure applied (z). Four current sense amplifiers (44) are provided for measuring the current flowing in the conductors 1~,15,21, 22. The outputs of the currents sense amplifiers are fed into two analogue summing circuits 35,37, one 35 for conductors 16~l5 covering the x dimension and the other 37 for conductors 21,22 covering the y dimension. The outputs of these summers are fed into dividers 36 and 38 respectively, along with one of the current sense outputs in each case.
The signal for x (and similarly for y) which this produces is not the simple ratio oi currents in opposed conductors 14,15 (or 21,22);
rather, if current in 14 = Il and current in 15 = I2 then the value of x is:
x = I2 Il+I2 This function is selected since it provides a result which varies approximately rectilinearly between 0 and 1.
The signal for z, representing the pressure applied by the stylus is simply a sum of the individual currents in conductors 14,15,21,22.
This is obtained by summing in 39 the sums of x and y currents produced by 35 and 37 respectively.
``~ 1 `~ Fig 3b shows a circuit for inputting x,y and z to a computer. The multiplexer 40 selects each of x,y,z in turn to forward to the analogue to digital convertor 41. The results are fed to buffer 42 and thence to data bus 43 which is connected to the computer.
Fig 4 shows an alternative arrangement to that of figs 3a,3b. In this case there is an additional current sense amplifier 45 for direct-ly measuring the current in conductor 30. This avoids the expense and inaccuracy of analogue summing circuit 39 (used in conjunction with 35 and 37). Further, the generation of the x and y functions is performed in the computer so the tablet does not need the local intelligence . , ,, ., . . , ~ , . .
~7~7 provided by circuits 35,36,37,38. This approach has the disadvantage that more processing is necessary in the computer so the maximum sampling rate will be lower but it does not require circuits 35,36,37, 38,39 so the hardware may well be cheaper to produce, In use, the conductive layer 11 of the tablet is held at a voltage equal to -10 Volts. The conductors 14,15,21,22 along the edges of resistive layer 10 are held at 0 Volts. When no pressure is applied to the upper surface of the tablet the physical contact between layers 10 and 11 is very slight and no significant current flows between them.
However, when localised pressure is applied to the upper surface the layers 10 and 11 are pushed into physical and electrical contact so that a currant flows from conductive layer 11 to the conductors 14,15, 21,22 connected to resistive layer 10. The current through each of these conductors is in inverse relation to the distance from the respective contact pad to the point where pressure is applied.
Another possibility is to have the arrangement as shown in fig 4 but without sense amplifier 45 (and its associated resistor). In this case the computer must sum all four conductor currents digitally. This is a processing overhead which reduces the maximum sampling rate but the hardware will be still cheaper to produce.
ig 5 shows the variation in the measured value of x versus the actual position at which pressure is applied. It can be seen that there are significant edge effects which mean that it may be necessary to process digitally the measurements once they are received by the co~puter in order to expand the measured x values to cover the entire range from 0 to l (0 is the left-hand edge of area 20 and 1 is the right-hand edge). It may also be necessary to take account of the y displacement when expanding the x readings since the x readings are compressed when taken near y=0 or y=l compared to readings taken near y=0.5. This is shown by the two lines on fig 5, line A being ~aken at y=0.5 (ie across the centre of the tablet) and line B being taken at y-0.9 (ie near the upper edge of the tablet).
~L2~ L77 Fig 6 shows the variation in measured total current (ie z) versus force applied to an area of tablet l.S millimetres square. It can be seen that this too would benefit from some digital processing, since the line produced is not as straight as ideally it should be. This would be straightforward to achieve if necessary, for example by employing a look-up table correlating measured current to applied pressure. It will be noted that below a certain non-zero value for the pressure the measured total current is zero. This is useful since it means that light pressure (eg from a person's hand) will not be detect-ed by the tablet and will not interfere with the normal operation of the tablet.
The variation in current with applied pressure stems from 2 effects. The first of these is that the resistive material compresses locally, so reducing the electrical resistance in the region of applied pressure since the fibres in the material are in better electrical contact. The second and more significant effect is that the contact area between the conductive and resistive layers increases.
The increase in contact area with increased pressure can cause the measured position to be in error. This happens when the pressure is applied significantly closer to one contact pad than to the opposed contact pad (eg closer to 16 than to 17). The increase in contact area with pressure is uniform ln all directions but since the contact area is closer to 16 than to 17, the distance from the contact area edge to 16 reduces by a greater percentage than the distance from the contact area edge to 17. This causes the measured position to appear further towards the near edge as more pressure is applied. If this effect is unacceptaSle then it would be necessary to compensate for it digitally in the computer by weighting the position measurement towards the centre, the level of weighting increasing with increasing pressure tie increasing total current).
Another compensation which may be required is to allow for the fact that, at a constant pressure, the total current increases as the , . . , ;-, contact point approaches any edge of the tablet. This is because the overall resistance through the resistive sheet from the contact point to the contact pads 16,17,23,24 decreases as the contact point moves further from the centre and closer to 1 or 2 of the contact pads. If this effect is too large to be ignored then a suitable weighting could be applied when the data is processed.
The rate at which the location and pressure of the stylus are sampled will depend on the requirements of the application and the circuitry and computer software employed. For graphics input to a terminal and for signature verification a sampling rate of around 10 kHz may be acceptable altkough a rate of around 20 kHz is preferable.
.i .
.. . .
,~. . .. .
: . .
Description Introduction This invention relates to a graphics input tablet. The invention is particularly useiul in the data processing field where it may be employed to input data of a graphical nature into a data processing machine.
Back~round Art In the data processing field one of the major problems to users of a system is the rapid inputting of data. This has traditionally been achieved with a keyboard but when it is necessary to input graphical data, rather than character strings, a keyboard is grossly inefficient.
There are various examples in the prior art of attempts to provide a more efficient and easier to use input means for graphical data.
One such example is disclosed in EP 5,996 (Quest Automation Ltd.) which shows an electrographic apparatus with two resistive layers, one overlying th~ other, held apart by a framework but arranged to be brought into contact by the pressure of a stylus or similar. Excitation voltages are applied to the resistlvs layer at 90 degrees to each other and two analogue voltages related to the position of the stylus are obtained in an unspecified manner.
Another example is disclosed in GB 2,088,063 (Robert Branton).
This shows a conductive layer overlying a rectangular resistive layer with an insulating mesh between the two. The resistive layer has a contact at each corner and one opposed pair of contacts ls energised at any one time. A stylus (ball-point pen or similar) is pressed onto the upper, conductive layer which then makes contact, through a gap in the insulating mesh, with the resistive layer. In consequence, the poten-. ~ . , ~Z5~7~77 tial of the conductive layer equals that of the resistive layer at the point of contact; since this varies with the relative distances of the point from each of the polarised contacts, the potential of the conduc-tive layer provides information to identify the position of the stylus.
Once the position with respect to these polarised contacts is estab-lished they are de-energised and the other pair is polarised to give information regarding the position of the stylus along a different axis. Thus the position of the stylus in 2 dimensions may be identi-fied.
Summar~ of_the Invention The prior art techniques only permit 2 dimensional input directly from the tablet; if a third dimension is required it must be input by other means eg a potentiometer arran~ed for manual control. The ability to input 3 dimensional data using the tablet alone would be very useful, for example a) to define the colour and/or intensity of a location on a graphic terminal or b) for signature verification where the profile of the pressure applied across the signature would be a useful additional check, above and beyond a 2 dimensional check of the appearance of the signature. Further, the prior art techniques do not permit the pressure information to be detected at all; this information could be useful, for example in the case of a one dimensional position-detecting tablet in the form of a strip. This would provide 2 dimen-sional input capability without occupying the large area taken up by a prior art 2-d input tablet.
Accordingly, the present invention provides a graphics input tablet comprising a layer of electrically resistive material supported co-extensively with a layer of electrically conductive material to provide a flat tabl0t surface, the resistive material having the property that the electrical resistance between the layers in the region of localised pressure applied thereto changes monotonically with the applied pressure, first and second conductors connected respective-ly to first and second portions of the resistive layer said portions ., 7~
being spaced apart on a first notional line across the tablet surface, the construction and arrangement being such that with an electrical potential applied between the resistive layer and the conductive layer substantially no current flows through said first and second conduc-tors, but with said localised pressure applied to said tablet surface currents flow through said first and second conductors, the relative magnitudes of the currents being related to the respective distances of the region of applied pressure from the first and second portions and the total current flowing between the resistive sheet and the conduc-tive sheet being related to the magnitude of the applied pressure.
! This provides the facility to detect the position of a stylus in two dimensions, ie one linear dimension and one pressure dimension.
Preferably, the graphics input tablet further comprises third and fourth conductors connected respectively to third and fourth portions of the resistive layer9 said portions being spaced apart on a second notional line, intersecting said first notional line, across the tablet surface, such that when said localised pressure is applied in said region currents flow in said third and fourth conductors9 the relative magnitudes of the currents in the third and fourth conductors being related to the respective distances of said third and fourth portions from the area of applied localised pressure.
This provides the facility to detect the position of a stylus in 3 dimensions, ie two linear dimensions and one pressure dimension.
Preferably, the graphics input tablet has electrical sensing means arranged to evaluate said total current by summing the individual currents measured in each of said conductors.
Alternatively, the graphics input tablet has electrical sensing means arranged to evaluate said total current from a measurement of the current flowing between the electrical excitation means and the conduc-tive layer.
, . ~ . ... .
~ ~7~
The resistive layer may be in the form of a single sheet of material. Alternatively, the resistive layer may comprise two sheets, each of a resistive material, the conductors being connected to a first of said sheets and the second of said sheets having the property as aforesaid that the electrical resistance between the layers in the region of localised pressure applied thereto changas monotonically with the magnitude of the pressure applied to the layers.
Description of the Drawings Figure la shows schematically a cross-section through a graphics lnput tablet according to the present invention.
Figure lb shows schematically a cross-section through an alterna-tive embodiment of a graphics input tablet according to the present invention.
Pigure 2 shows schematically a plan view of the tablet of fig la.
Fig 3a shows schematically a circuit for processing signals representing positional and pressure information produced by the present invention.
Fig 3b shows schematically a circuit for inputting the outputs of the circuit of fig 3a into a computer.
Fig 4 shows schematically an alternative circuit for processing signals representing positional and pressure information produced by the present invention and inputting this into a computer.
Fig S is a schematic graph showing variations in positional measurements versus actual position when employing the present inven-tion.
~'71~
Fig 6 is a schematic graph showing variations in measured total current versus actual force applied to a small area using the present invention.
Detailed Description of the Invention Fig la shows a graphics input tablet according to the present invention. Layer 10 is a compressible resistive sheet known as Verma-hide (Trade Mark). This material has the property that its localised electrical resistance reduces with increased pressure exerted on it as the electrically conducting fibres which make it up are forced into more intimate contact. Beneath layer 10 is layer 11 which is an elec-trically conducting coat applied to insulating substrate 13. Beneath insulating substrate 13 is conductive coat 50 which may be electrically grounded to give electrostatic screening. Layers 11,13,50 may con-veniently be provided by double-sided unetched printed circuit board.
Overlying layers 10,11,13,50 is protective sheet 12 which is electri-cally insulating, physically hard-wearing and yet locally elastically deformable. Electrical connection is made to conductive layer 11 by conductor 30 and to opposed edges of resist~ve layer 10 by conductors 14,15,21,22 (see fig Z).
FiB lb shows an alternative tablet comprising two resistive sheets, one compressible 10a and one rigid 10b. Conductive layer 11 overlies the resistive sheets and is locally elastically deformable.
Fig 2 shows a plan view of the tablet in fig la. Contact pads 16,17,23,24 are shown, attached to conductors 14,15,21,22 respectively.
Each contact pad makes electrical contact with a portion of the resis-tive layer: 16,17,23,24 contacting 18,19,25,26 respectively. This leaves the remainder 20 of layer 10 as the input region where a user applies localised pressure with a stylus, causing currents to flow in conductors 14,15,21,22.
Fig 3a shows one technique for producing signals x,y,z represent-i~ . .~, .. .
lZ97177 ing the position of pressure applied on region 20 (x,y) and the magni-tude o~ pressure applied (z). Four current sense amplifiers (44) are provided for measuring the current flowing in the conductors 1~,15,21, 22. The outputs of the currents sense amplifiers are fed into two analogue summing circuits 35,37, one 35 for conductors 16~l5 covering the x dimension and the other 37 for conductors 21,22 covering the y dimension. The outputs of these summers are fed into dividers 36 and 38 respectively, along with one of the current sense outputs in each case.
The signal for x (and similarly for y) which this produces is not the simple ratio oi currents in opposed conductors 14,15 (or 21,22);
rather, if current in 14 = Il and current in 15 = I2 then the value of x is:
x = I2 Il+I2 This function is selected since it provides a result which varies approximately rectilinearly between 0 and 1.
The signal for z, representing the pressure applied by the stylus is simply a sum of the individual currents in conductors 14,15,21,22.
This is obtained by summing in 39 the sums of x and y currents produced by 35 and 37 respectively.
``~ 1 `~ Fig 3b shows a circuit for inputting x,y and z to a computer. The multiplexer 40 selects each of x,y,z in turn to forward to the analogue to digital convertor 41. The results are fed to buffer 42 and thence to data bus 43 which is connected to the computer.
Fig 4 shows an alternative arrangement to that of figs 3a,3b. In this case there is an additional current sense amplifier 45 for direct-ly measuring the current in conductor 30. This avoids the expense and inaccuracy of analogue summing circuit 39 (used in conjunction with 35 and 37). Further, the generation of the x and y functions is performed in the computer so the tablet does not need the local intelligence . , ,, ., . . , ~ , . .
~7~7 provided by circuits 35,36,37,38. This approach has the disadvantage that more processing is necessary in the computer so the maximum sampling rate will be lower but it does not require circuits 35,36,37, 38,39 so the hardware may well be cheaper to produce, In use, the conductive layer 11 of the tablet is held at a voltage equal to -10 Volts. The conductors 14,15,21,22 along the edges of resistive layer 10 are held at 0 Volts. When no pressure is applied to the upper surface of the tablet the physical contact between layers 10 and 11 is very slight and no significant current flows between them.
However, when localised pressure is applied to the upper surface the layers 10 and 11 are pushed into physical and electrical contact so that a currant flows from conductive layer 11 to the conductors 14,15, 21,22 connected to resistive layer 10. The current through each of these conductors is in inverse relation to the distance from the respective contact pad to the point where pressure is applied.
Another possibility is to have the arrangement as shown in fig 4 but without sense amplifier 45 (and its associated resistor). In this case the computer must sum all four conductor currents digitally. This is a processing overhead which reduces the maximum sampling rate but the hardware will be still cheaper to produce.
ig 5 shows the variation in the measured value of x versus the actual position at which pressure is applied. It can be seen that there are significant edge effects which mean that it may be necessary to process digitally the measurements once they are received by the co~puter in order to expand the measured x values to cover the entire range from 0 to l (0 is the left-hand edge of area 20 and 1 is the right-hand edge). It may also be necessary to take account of the y displacement when expanding the x readings since the x readings are compressed when taken near y=0 or y=l compared to readings taken near y=0.5. This is shown by the two lines on fig 5, line A being ~aken at y=0.5 (ie across the centre of the tablet) and line B being taken at y-0.9 (ie near the upper edge of the tablet).
~L2~ L77 Fig 6 shows the variation in measured total current (ie z) versus force applied to an area of tablet l.S millimetres square. It can be seen that this too would benefit from some digital processing, since the line produced is not as straight as ideally it should be. This would be straightforward to achieve if necessary, for example by employing a look-up table correlating measured current to applied pressure. It will be noted that below a certain non-zero value for the pressure the measured total current is zero. This is useful since it means that light pressure (eg from a person's hand) will not be detect-ed by the tablet and will not interfere with the normal operation of the tablet.
The variation in current with applied pressure stems from 2 effects. The first of these is that the resistive material compresses locally, so reducing the electrical resistance in the region of applied pressure since the fibres in the material are in better electrical contact. The second and more significant effect is that the contact area between the conductive and resistive layers increases.
The increase in contact area with increased pressure can cause the measured position to be in error. This happens when the pressure is applied significantly closer to one contact pad than to the opposed contact pad (eg closer to 16 than to 17). The increase in contact area with pressure is uniform ln all directions but since the contact area is closer to 16 than to 17, the distance from the contact area edge to 16 reduces by a greater percentage than the distance from the contact area edge to 17. This causes the measured position to appear further towards the near edge as more pressure is applied. If this effect is unacceptaSle then it would be necessary to compensate for it digitally in the computer by weighting the position measurement towards the centre, the level of weighting increasing with increasing pressure tie increasing total current).
Another compensation which may be required is to allow for the fact that, at a constant pressure, the total current increases as the , . . , ;-, contact point approaches any edge of the tablet. This is because the overall resistance through the resistive sheet from the contact point to the contact pads 16,17,23,24 decreases as the contact point moves further from the centre and closer to 1 or 2 of the contact pads. If this effect is too large to be ignored then a suitable weighting could be applied when the data is processed.
The rate at which the location and pressure of the stylus are sampled will depend on the requirements of the application and the circuitry and computer software employed. For graphics input to a terminal and for signature verification a sampling rate of around 10 kHz may be acceptable altkough a rate of around 20 kHz is preferable.
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Claims (20)
1. A graphics input tablet comprising a layer of electrically resistive material supported co-extensively with a layer of electrically conductive material to provide a flat tablet surface, the resistive material having the property that the electrical resistance between the layers in the region of localised pressure applied thereto changes monotonically with the applied pressure, first and second conductors connected respectively to first and second portions of the resistive layer, said portions being spaced apart on a first notional line across the tablet surface, the construction and arrangement being such that with an electrical potential applied between the resistive layer and the conductive layer substantially no current flows through said first and second conductors, but with said localised pressure applied to said tablet surface currents flow through said first and second conductors, the relative magnitudes of the currents being related to the respective distances of the region of applied pressure from the first and second portions and the total current flowing between the resistive sheet and the conductive sheet being related to the magnitude of the applied pressure.
2. A graphics input tablet as claimed in claim 1, further comprising third and fourth conductors connected respectively to third and fourth portions of the resistive layer, said portions being spaced apart on a second notional line, intersecting said first notional line, across the tablet surface, such that when said localised pressure is applied in said region currents flow in said third and fourth conductors, the relative magnitudes of the currents in the third and fourth conductors being related to the respective distances of said third and fourth portions from the area of applied localised pressure.
3. A graphics input tablet as claimed in claim 1 further comprising electrical excitation means for applying said electrical potential between the resistive layer and the conductive layer.
4. A graphics input tablet as claimed in claim 2 further comprising electrical excitation means for applying said electrical potential between the resistive layer and the conductive layer.
5. A graphics input tablet as claimed in claim 1 further comprising electrical sensing means arranged to measure individually the current flowing in each of said conductors and to evaluate the total current flowing between the resistive layer and the conductive layer.
6. A graphics input tablet as claimed in claim 2 further comprising electrical sensing means arranged to measure individually the current flowing in each of said conductors and to evaluate the total current flowing between the resistive layer and the conductive layer.
7. A graphics input tablet as claimed in claim 3 further comprising electrical sensing means arranged to measure individually the current flowing in each of said conductors and to evaluate the total current flowing between the resistive layer and the conductive layer.
8. A graphics input tablet as claimed in claim 4 further comprising electrical sensing means arranged to measure individually the current flowing in each of said conductors and to evaluate the total current flowing between the resistive layer and the conductive layer.
9. A graphics input tablet as claimed in claims 5 or 6 in which said electrical sensing means is arranged to evaluate said total current by summing the individual currents measured in each of said conductors.
10. A graphics input tablet as claimed in claims 7 or 8 in which said electrical sensing means is arranged to evaluate said total current by summing the individual currents measured in each of said conductors.
11. A graphics input tablet as claimed in claims 5 or 6 in which said electrical sensing means is arranged to evaluate said total current from a measurement of the current flowing between the electrical excitation means and the conductive layer.
12. A graphics input tablet as claimed in claims 7 or 8 in which said electrical sensing means is arranged to evaluate said total current from a measurement of the current flowing between the electrical excitation means and the conductive layer.
13. A graphics input tablet as claimed in claims 1, 2 or 3 in which said resistive layer is rectangular and said conductors are connected each to a different edge of said resistive layer such that each said portion represents substantially the whole of an edge of the resistive layer.
14. A graphics input tablet as claimed in claims 4, 5 or 6 in which said resistive layer is rectangular and said conductors are connected each to a different edge of said resistive layer such that each said portion represents substantially the whole of an edge of the resistive layer.
15. A graphics input tablet as claimed in claims 1, 2 or 3 in which the resistive layer comprises two sheets, each of a resistive material, the conductors being connected to a first of said sheets and the second of said sheets providing the property as aforesaid that the electrical resistance between the layers in the region of localised pressure applied thereto changes monotonically with the magnitude of the pressure applied to the layers.
16. A graphics input tablet as claimed in claims 4, 5 or 6 in which the resistive layer comprises two sheets, each of a resistive material, the conductors being connected to a first of said sheets and the second of said sheets providing the property as aforesaid that the electrical resistance between the layers in the region of localised pressure applied thereto changes monotonically with the magnitude of the pressure applied to the layers.
17. A graphics input tablet as claimed in claims 1, 2 or 3 in which the electrical sensing means comprises analogue current measuring means, said tablet further comprising analogue summing means and analogue dividing means.
18. A graphics input tablet as claimed in claims 4, 5 or 6 in which the electrical sensing means comprises analogue current measuring means, said tablet further comprising analogue summing means and analogue dividing means.
19. A graphics input tablet as claimed in claims 1, 2 or 3 further comprising analogue to digital conversion means and buffering means for buffering an output of the analogue to digital conversion means onto a data bus connected to a data processing means.
20. A graphics input tablet as claimed in claims 4, 5 or 6 further comprising analogue to digital conversion means and buffering means for buffering an output of the analogue to digital conversion means onto a data bus connected to a data processing means.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB8710033A GB2204131B (en) | 1987-04-28 | 1987-04-28 | Graphics input tablet |
GB8710033 | 1987-04-28 |
Publications (1)
Publication Number | Publication Date |
---|---|
CA1297177C true CA1297177C (en) | 1992-03-10 |
Family
ID=10616483
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CA000564186A Expired - Fee Related CA1297177C (en) | 1987-04-28 | 1988-04-14 | Graphics input tablet |
Country Status (6)
Country | Link |
---|---|
US (1) | US4798919A (en) |
EP (1) | EP0288692B1 (en) |
JP (1) | JPS63276117A (en) |
CA (1) | CA1297177C (en) |
DE (1) | DE3882268T2 (en) |
GB (1) | GB2204131B (en) |
Families Citing this family (147)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0350638B1 (en) * | 1988-07-14 | 1993-12-15 | Blomberg Robotertechnik GmbH | Tactile sensor |
US5159159A (en) * | 1990-12-07 | 1992-10-27 | Asher David J | Touch sensor and controller |
JP2516502B2 (en) * | 1991-09-25 | 1996-07-24 | 日本写真印刷株式会社 | Input device |
US5262777A (en) * | 1991-11-16 | 1993-11-16 | Sri International | Device for generating multidimensional input signals to a computer |
US5550330A (en) * | 1991-10-16 | 1996-08-27 | Fanuc Limited | Digitizing control apparatus |
LU88033A1 (en) * | 1991-11-13 | 1993-05-17 | Iee Sarl | Digitizing tablet |
US5335557A (en) * | 1991-11-26 | 1994-08-09 | Taizo Yasutake | Touch sensitive input control device |
US6597347B1 (en) | 1991-11-26 | 2003-07-22 | Itu Research Inc. | Methods and apparatus for providing touch-sensitive input in multiple degrees of freedom |
USRE40891E1 (en) | 1991-11-26 | 2009-09-01 | Sandio Technology Corp. | Methods and apparatus for providing touch-sensitive input in multiple degrees of freedom |
US5369228A (en) * | 1991-11-30 | 1994-11-29 | Signagraphics Corporation | Data input device with a pressure-sensitive input surface |
US5451724A (en) * | 1992-08-05 | 1995-09-19 | Fujitsu Limited | Touch panel for detecting a coordinate of an arbitrary position where pressure is applied |
KR200151013Y1 (en) * | 1993-04-20 | 1999-07-15 | 손욱 | Digitizer |
JP3201874B2 (en) * | 1993-04-23 | 2001-08-27 | エスエムケイ株式会社 | Method and apparatus for detecting coordinates of resistance pressure-sensitive tablet |
US5734373A (en) * | 1993-07-16 | 1998-03-31 | Immersion Human Interface Corporation | Method and apparatus for controlling force feedback interface systems utilizing a host computer |
US5724264A (en) * | 1993-07-16 | 1998-03-03 | Immersion Human Interface Corp. | Method and apparatus for tracking the position and orientation of a stylus and for digitizing a 3-D object |
US5739811A (en) * | 1993-07-16 | 1998-04-14 | Immersion Human Interface Corporation | Method and apparatus for controlling human-computer interface systems providing force feedback |
US6437771B1 (en) * | 1995-01-18 | 2002-08-20 | Immersion Corporation | Force feedback device including flexure member between actuator and user object |
US5721566A (en) * | 1995-01-18 | 1998-02-24 | Immersion Human Interface Corp. | Method and apparatus for providing damping force feedback |
US5805140A (en) | 1993-07-16 | 1998-09-08 | Immersion Corporation | High bandwidth force feedback interface using voice coils and flexures |
US5767839A (en) * | 1995-01-18 | 1998-06-16 | Immersion Human Interface Corporation | Method and apparatus for providing passive force feedback to human-computer interface systems |
US5731804A (en) * | 1995-01-18 | 1998-03-24 | Immersion Human Interface Corp. | Method and apparatus for providing high bandwidth, low noise mechanical I/O for computer systems |
US5466895A (en) * | 1994-01-07 | 1995-11-14 | Microtouch Systems, Inc. | Wear resistant improved tablet for a digitizer |
FI103837B1 (en) * | 1994-12-22 | 1999-09-30 | Nokia Mobile Phones Ltd | Method of transmission and processing |
US6850222B1 (en) | 1995-01-18 | 2005-02-01 | Immersion Corporation | Passive force feedback for computer interface devices |
US5691898A (en) * | 1995-09-27 | 1997-11-25 | Immersion Human Interface Corp. | Safe and low cost computer peripherals with force feedback for consumer applications |
US6166723A (en) * | 1995-11-17 | 2000-12-26 | Immersion Corporation | Mouse interface device providing force feedback |
US7113166B1 (en) | 1995-06-09 | 2006-09-26 | Immersion Corporation | Force feedback devices using fluid braking |
US6697748B1 (en) * | 1995-08-07 | 2004-02-24 | Immersion Corporation | Digitizing system and rotary table for determining 3-D geometry of an object |
US5959613A (en) | 1995-12-01 | 1999-09-28 | Immersion Corporation | Method and apparatus for shaping force signals for a force feedback device |
US5825308A (en) * | 1996-11-26 | 1998-10-20 | Immersion Human Interface Corporation | Force feedback interface having isotonic and isometric functionality |
US6100874A (en) | 1995-11-17 | 2000-08-08 | Immersion Corporation | Force feedback mouse interface |
US6704001B1 (en) * | 1995-11-17 | 2004-03-09 | Immersion Corporation | Force feedback device including actuator with moving magnet |
US6219032B1 (en) * | 1995-12-01 | 2001-04-17 | Immersion Corporation | Method for providing force feedback to a user of an interface device based on interactions of a controlled cursor with graphical elements in a graphical user interface |
US8508469B1 (en) | 1995-12-01 | 2013-08-13 | Immersion Corporation | Networked applications including haptic feedback |
US6028593A (en) | 1995-12-01 | 2000-02-22 | Immersion Corporation | Method and apparatus for providing simulated physical interactions within computer generated environments |
US6147674A (en) | 1995-12-01 | 2000-11-14 | Immersion Corporation | Method and apparatus for designing force sensations in force feedback computer applications |
US7027032B2 (en) * | 1995-12-01 | 2006-04-11 | Immersion Corporation | Designing force sensations for force feedback computer applications |
US6859819B1 (en) | 1995-12-13 | 2005-02-22 | Immersion Corporation | Force feedback enabled over a computer network |
US6078308A (en) * | 1995-12-13 | 2000-06-20 | Immersion Corporation | Graphical click surfaces for force feedback applications to provide user selection using cursor interaction with a trigger position within a boundary of a graphical object |
US5940065A (en) * | 1996-03-15 | 1999-08-17 | Elo Touchsystems, Inc. | Algorithmic compensation system and method therefor for a touch sensor panel |
US6054979A (en) * | 1996-08-21 | 2000-04-25 | Compaq Computer Corporation | Current sensing touchpad for computers and the like |
US7489309B2 (en) * | 1996-11-26 | 2009-02-10 | Immersion Corporation | Control knob with multiple degrees of freedom and force feedback |
US6686911B1 (en) | 1996-11-26 | 2004-02-03 | Immersion Corporation | Control knob with control modes and force feedback |
GB9722766D0 (en) | 1997-10-28 | 1997-12-24 | British Telecomm | Portable computers |
US7808479B1 (en) | 2003-09-02 | 2010-10-05 | Apple Inc. | Ambidextrous mouse |
US7844914B2 (en) | 2004-07-30 | 2010-11-30 | Apple Inc. | Activating virtual keys of a touch-screen virtual keyboard |
KR100595920B1 (en) | 1998-01-26 | 2006-07-05 | 웨인 웨스터만 | Method and apparatus for integrating manual input |
US9239673B2 (en) | 1998-01-26 | 2016-01-19 | Apple Inc. | Gesturing with a multipoint sensing device |
US8479122B2 (en) | 2004-07-30 | 2013-07-02 | Apple Inc. | Gestures for touch sensitive input devices |
US7614008B2 (en) | 2004-07-30 | 2009-11-03 | Apple Inc. | Operation of a computer with touch screen interface |
US9292111B2 (en) | 1998-01-26 | 2016-03-22 | Apple Inc. | Gesturing with a multipoint sensing device |
US7663607B2 (en) | 2004-05-06 | 2010-02-16 | Apple Inc. | Multipoint touchscreen |
US6369804B1 (en) | 1998-09-26 | 2002-04-09 | Eleksen Limited | Detector constructed from fabric having non-uniform conductivity |
GB0007679D0 (en) * | 2000-03-30 | 2000-05-17 | Electrotextiles Comp Ltd | Data input device |
US6333736B1 (en) | 1999-05-20 | 2001-12-25 | Electrotextiles Company Limited | Detector constructed from fabric |
US6504531B1 (en) | 1999-05-20 | 2003-01-07 | Eleksen Limited | Detecting mechanical interactions |
US7161084B2 (en) * | 2000-03-30 | 2007-01-09 | Electrotextiles Company Limited | Detector constructed from electrically conducting fabric |
JP2003529837A (en) * | 2000-03-30 | 2003-10-07 | エレクセン・リミテッド | Manual input device and processor |
WO2001075922A1 (en) | 2000-03-30 | 2001-10-11 | Eleksen Limited | Data input device |
AU770743B2 (en) * | 2000-04-03 | 2004-03-04 | Intelligent Textiles Limited | Conductive pressure sensitive textile |
US6909354B2 (en) | 2001-02-08 | 2005-06-21 | Interlink Electronics, Inc. | Electronic pressure sensitive transducer apparatus and method for manufacturing same |
US7030861B1 (en) | 2001-02-10 | 2006-04-18 | Wayne Carl Westerman | System and method for packing multi-touch gestures onto a hand |
US7567232B2 (en) * | 2001-03-09 | 2009-07-28 | Immersion Corporation | Method of using tactile feedback to deliver silent status information to a user of an electronic device |
DE10122634A1 (en) * | 2001-05-10 | 2002-11-14 | Bs Biometric Systems Gmbh | Tray especially graphics tablet |
US7046230B2 (en) * | 2001-10-22 | 2006-05-16 | Apple Computer, Inc. | Touch pad handheld device |
US20070085841A1 (en) * | 2001-10-22 | 2007-04-19 | Apple Computer, Inc. | Method and apparatus for accelerated scrolling |
US7345671B2 (en) | 2001-10-22 | 2008-03-18 | Apple Inc. | Method and apparatus for use of rotational user inputs |
US7312785B2 (en) | 2001-10-22 | 2007-12-25 | Apple Inc. | Method and apparatus for accelerated scrolling |
KR20090082519A (en) * | 2001-10-23 | 2009-07-30 | 임머숀 코퍼레이션 | Method of using tactile feedback to deliver silent status information to a user of an electronic device |
EP1440414B1 (en) * | 2001-10-30 | 2016-08-17 | Immersion Corporation | Methods and apparatus for providing haptic feedback in interacting with virtual pets |
US7535454B2 (en) | 2001-11-01 | 2009-05-19 | Immersion Corporation | Method and apparatus for providing haptic feedback |
CN1582465B (en) | 2001-11-01 | 2013-07-24 | 伊梅森公司 | Input device and mobile telephone comprising the input device |
GB2383419B (en) * | 2001-12-21 | 2004-07-07 | Motorola Inc | Display devices |
US7333092B2 (en) * | 2002-02-25 | 2008-02-19 | Apple Computer, Inc. | Touch pad for handheld device |
US7656393B2 (en) | 2005-03-04 | 2010-02-02 | Apple Inc. | Electronic device having display and surrounding touch sensitive bezel for user interface and control |
US11275405B2 (en) | 2005-03-04 | 2022-03-15 | Apple Inc. | Multi-functional hand-held device |
US7769417B2 (en) * | 2002-12-08 | 2010-08-03 | Immersion Corporation | Method and apparatus for providing haptic feedback to off-activating area |
US7050045B2 (en) * | 2003-01-07 | 2006-05-23 | Interlink Electronics, Inc. | Miniature highly manufacturable mouse pointing device |
EP1469378A1 (en) * | 2003-04-16 | 2004-10-20 | IEE INTERNATIONAL ELECTRONICS & ENGINEERING S.A. | Position detection apparatus |
US20070152977A1 (en) * | 2005-12-30 | 2007-07-05 | Apple Computer, Inc. | Illuminated touchpad |
US20060181517A1 (en) * | 2005-02-11 | 2006-08-17 | Apple Computer, Inc. | Display actuator |
US7499040B2 (en) * | 2003-08-18 | 2009-03-03 | Apple Inc. | Movable touch pad with added functionality |
US20050076824A1 (en) * | 2003-10-08 | 2005-04-14 | Cross Elisa M. | Resistive touch screen incorporating conductive polymer |
US8059099B2 (en) | 2006-06-02 | 2011-11-15 | Apple Inc. | Techniques for interactive input to portable electronic devices |
US7495659B2 (en) * | 2003-11-25 | 2009-02-24 | Apple Inc. | Touch pad for handheld device |
GB0404419D0 (en) * | 2004-02-27 | 2004-03-31 | Intelligent Textiles Ltd | Electrical components and circuits constructed as textiles |
US7653883B2 (en) | 2004-07-30 | 2010-01-26 | Apple Inc. | Proximity detector in handheld device |
US8381135B2 (en) | 2004-07-30 | 2013-02-19 | Apple Inc. | Proximity detector in handheld device |
CN100555200C (en) | 2004-08-16 | 2009-10-28 | 苹果公司 | The method of the spatial resolution of touch sensitive devices and raising touch sensitive devices |
US7671837B2 (en) * | 2005-09-06 | 2010-03-02 | Apple Inc. | Scrolling input arrangements using capacitive sensors on a flexible membrane |
US7880729B2 (en) * | 2005-10-11 | 2011-02-01 | Apple Inc. | Center button isolation ring |
US20070152983A1 (en) * | 2005-12-30 | 2007-07-05 | Apple Computer, Inc. | Touch pad with symbols based on mode |
US7538760B2 (en) | 2006-03-30 | 2009-05-26 | Apple Inc. | Force imaging input device and system |
US7978181B2 (en) | 2006-04-25 | 2011-07-12 | Apple Inc. | Keystroke tactility arrangement on a smooth touch surface |
US8279180B2 (en) | 2006-05-02 | 2012-10-02 | Apple Inc. | Multipoint touch surface controller |
CN104965621B (en) | 2006-06-09 | 2018-06-12 | 苹果公司 | Touch screen LCD and its operating method |
US8259078B2 (en) | 2006-06-09 | 2012-09-04 | Apple Inc. | Touch screen liquid crystal display |
KR102125605B1 (en) | 2006-06-09 | 2020-06-22 | 애플 인크. | Touch screen liquid crystal display |
US9360967B2 (en) * | 2006-07-06 | 2016-06-07 | Apple Inc. | Mutual capacitance touch sensing device |
US8743060B2 (en) | 2006-07-06 | 2014-06-03 | Apple Inc. | Mutual capacitance touch sensing device |
US8022935B2 (en) | 2006-07-06 | 2011-09-20 | Apple Inc. | Capacitance sensing electrode with integrated I/O mechanism |
US20080006454A1 (en) * | 2006-07-10 | 2008-01-10 | Apple Computer, Inc. | Mutual capacitance touch sensing device |
US7573464B2 (en) * | 2006-07-20 | 2009-08-11 | Interlink Electronics, Inc. | Shape adaptable resistive touchpad |
US7795553B2 (en) | 2006-09-11 | 2010-09-14 | Apple Inc. | Hybrid button |
US8274479B2 (en) * | 2006-10-11 | 2012-09-25 | Apple Inc. | Gimballed scroll wheel |
US20080088600A1 (en) * | 2006-10-11 | 2008-04-17 | Apple Inc. | Method and apparatus for implementing multiple push buttons in a user input device |
US20080088597A1 (en) * | 2006-10-11 | 2008-04-17 | Apple Inc. | Sensor configurations in a user input device |
US8482530B2 (en) * | 2006-11-13 | 2013-07-09 | Apple Inc. | Method of capacitively sensing finger position |
WO2008085487A1 (en) * | 2006-12-27 | 2008-07-17 | Immersion Corporation | Virtual detents through vibrotactile feedback |
US8493330B2 (en) | 2007-01-03 | 2013-07-23 | Apple Inc. | Individual channel phase delay scheme |
US9710095B2 (en) | 2007-01-05 | 2017-07-18 | Apple Inc. | Touch screen stack-ups |
US9654104B2 (en) * | 2007-07-17 | 2017-05-16 | Apple Inc. | Resistive force sensor with capacitive discrimination |
US7910843B2 (en) * | 2007-09-04 | 2011-03-22 | Apple Inc. | Compact input device |
US8683378B2 (en) * | 2007-09-04 | 2014-03-25 | Apple Inc. | Scrolling techniques for user interfaces |
US20090058801A1 (en) * | 2007-09-04 | 2009-03-05 | Apple Inc. | Fluid motion user interface control |
US20090073130A1 (en) * | 2007-09-17 | 2009-03-19 | Apple Inc. | Device having cover with integrally formed sensor |
US8416198B2 (en) * | 2007-12-03 | 2013-04-09 | Apple Inc. | Multi-dimensional scroll wheel |
US8125461B2 (en) * | 2008-01-11 | 2012-02-28 | Apple Inc. | Dynamic input graphic display |
US8820133B2 (en) * | 2008-02-01 | 2014-09-02 | Apple Inc. | Co-extruded materials and methods |
US9454256B2 (en) | 2008-03-14 | 2016-09-27 | Apple Inc. | Sensor configurations of an input device that are switchable based on mode |
US8217908B2 (en) | 2008-06-19 | 2012-07-10 | Tactile Displays, Llc | Apparatus and method for interactive display with tactile feedback |
US8665228B2 (en) | 2008-06-19 | 2014-03-04 | Tactile Displays, Llc | Energy efficient interactive display with energy regenerative keyboard |
US9513705B2 (en) | 2008-06-19 | 2016-12-06 | Tactile Displays, Llc | Interactive display with tactile feedback |
US8115745B2 (en) | 2008-06-19 | 2012-02-14 | Tactile Displays, Llc | Apparatus and method for interactive display with tactile feedback |
US20100058251A1 (en) * | 2008-08-27 | 2010-03-04 | Apple Inc. | Omnidirectional gesture detection |
US8749495B2 (en) * | 2008-09-24 | 2014-06-10 | Immersion Corporation | Multiple actuation handheld device |
US8816967B2 (en) | 2008-09-25 | 2014-08-26 | Apple Inc. | Capacitive sensor having electrodes arranged on the substrate and the flex circuit |
US8500732B2 (en) * | 2008-10-21 | 2013-08-06 | Hermes Innovations Llc | Endometrial ablation devices and systems |
US8395590B2 (en) * | 2008-12-17 | 2013-03-12 | Apple Inc. | Integrated contact switch and touch sensor elements |
US9354751B2 (en) * | 2009-05-15 | 2016-05-31 | Apple Inc. | Input device with optimized capacitive sensing |
US8872771B2 (en) * | 2009-07-07 | 2014-10-28 | Apple Inc. | Touch sensing device having conductive nodes |
US8654524B2 (en) | 2009-08-17 | 2014-02-18 | Apple Inc. | Housing as an I/O device |
US8988191B2 (en) * | 2009-08-27 | 2015-03-24 | Symbol Technologies, Inc. | Systems and methods for pressure-based authentication of an input on a touch screen |
JP5429814B2 (en) * | 2010-03-29 | 2014-02-26 | 株式会社ワコム | Indicator detection device and detection sensor |
US10719131B2 (en) | 2010-04-05 | 2020-07-21 | Tactile Displays, Llc | Interactive display with tactile feedback |
US20200393907A1 (en) | 2010-04-13 | 2020-12-17 | Tactile Displays, Llc | Interactive display with tactile feedback |
US8576171B2 (en) | 2010-08-13 | 2013-11-05 | Immersion Corporation | Systems and methods for providing haptic feedback to touch-sensitive input devices |
US8804056B2 (en) | 2010-12-22 | 2014-08-12 | Apple Inc. | Integrated touch screens |
CA2763271A1 (en) * | 2011-01-11 | 2012-07-11 | Egan Teamboard Inc. | Dimensionally stable white board |
US20120176328A1 (en) * | 2011-01-11 | 2012-07-12 | Egan Teamboard Inc. | White board operable by variable pressure inputs |
FR2971066B1 (en) | 2011-01-31 | 2013-08-23 | Nanotec Solution | THREE-DIMENSIONAL MAN-MACHINE INTERFACE. |
US9582178B2 (en) | 2011-11-07 | 2017-02-28 | Immersion Corporation | Systems and methods for multi-pressure interaction on touch-sensitive surfaces |
US9891709B2 (en) | 2012-05-16 | 2018-02-13 | Immersion Corporation | Systems and methods for content- and context specific haptic effects using predefined haptic effects |
FR3002052B1 (en) | 2013-02-14 | 2016-12-09 | Fogale Nanotech | METHOD AND DEVICE FOR NAVIGATING A DISPLAY SCREEN AND APPARATUS COMPRISING SUCH A NAVIGATION |
US9904394B2 (en) | 2013-03-13 | 2018-02-27 | Immerson Corporation | Method and devices for displaying graphical user interfaces based on user contact |
US9547366B2 (en) | 2013-03-14 | 2017-01-17 | Immersion Corporation | Systems and methods for haptic and gesture-driven paper simulation |
BR112018010317A2 (en) | 2015-12-18 | 2018-12-04 | Intelligent Textiles Ltd | conductive fabric, method of manufacturing a conductive fabric, same system and article of clothing |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6029965B2 (en) * | 1982-03-10 | 1985-07-13 | 日本電信電話株式会社 | Graphic input device |
JPS58191089A (en) * | 1982-04-30 | 1983-11-08 | Toyo Commun Equip Co Ltd | Position detecting method |
JPS5985583A (en) * | 1982-11-08 | 1984-05-17 | Nippon Telegr & Teleph Corp <Ntt> | Tablet |
US4575580A (en) * | 1984-04-06 | 1986-03-11 | Astec International, Ltd. | Data input device with a circuit responsive to stylus up/down position |
US4687885A (en) * | 1985-03-11 | 1987-08-18 | Elographics, Inc. | Electrographic touch sensor with Z-axis capability |
-
1987
- 1987-04-28 GB GB8710033A patent/GB2204131B/en not_active Expired - Fee Related
-
1988
- 1988-03-04 EP EP88103374A patent/EP0288692B1/en not_active Expired - Lifetime
- 1988-03-04 DE DE88103374T patent/DE3882268T2/en not_active Expired - Fee Related
- 1988-03-11 US US07/166,957 patent/US4798919A/en not_active Expired - Lifetime
- 1988-03-17 JP JP63062114A patent/JPS63276117A/en active Granted
- 1988-04-14 CA CA000564186A patent/CA1297177C/en not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
EP0288692B1 (en) | 1993-07-14 |
EP0288692A3 (en) | 1990-01-24 |
GB2204131A (en) | 1988-11-02 |
JPS63276117A (en) | 1988-11-14 |
EP0288692A2 (en) | 1988-11-02 |
GB8710033D0 (en) | 1987-06-03 |
GB2204131B (en) | 1991-04-17 |
DE3882268T2 (en) | 1994-02-17 |
US4798919A (en) | 1989-01-17 |
JPH0563815B2 (en) | 1993-09-13 |
DE3882268D1 (en) | 1993-08-19 |
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MKLA | Lapsed |