US3627431A - Densitometer - Google Patents

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US3627431A
US3627431A US887122A US3627431DA US3627431A US 3627431 A US3627431 A US 3627431A US 887122 A US887122 A US 887122A US 3627431D A US3627431D A US 3627431DA US 3627431 A US3627431 A US 3627431A
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light
samples
slide
photographic paper
sample
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John Victor Komarniski
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
    • G01N21/251—Colorimeters; Construction thereof
    • G01N21/253—Colorimeters; Construction thereof for batch operation, i.e. multisample apparatus

Definitions

  • the device of the present invention obviates these difiiculties by providing a densitometer or a colorimeter whereby a large number of samples can be read at the same time. Thus, the results are directly comparable.
  • FIG. I is a perspective view of an embodiment of the present invention wherein the light passes vertically through the samples and wherein a photographic paper is used as the recording means.
  • FIG. 2 is an enlarged view of a single sample cell wherein the cell itself incorporates a lens.
  • FIG. 3 is another embodiment of the invention wherein the light passes horizontally through the samples.
  • FIG. 4 is a side view in section of a device similar to that shown in FIG. 1 except that an ordinary camera is employed for recording and a condensing lens is used to focus the image ofthe bottom of the cells into the camera lens.
  • FIG. 5 is a partial view of a device similar to that shown in FIG. 4 except that prisms are employed instead of the condensing lens.
  • FIG. I there is shown a colorimeter which is built in the form of a cabinet, generally designated 5, having a sample holder 7 thereon.
  • a diffuser I3 is provided so that the light will be uniform on all of the samples.
  • the diffuser is a sheet of ground or opal glass.
  • filter 16 which yields a gray scale which is indicative of concentration or the like so that the optical density of the test sample can be determined. Filter 16 is not necessary in all instances.
  • a shutter mechanism 17 may be employed if desired although this is ordinarily not necessary since it is sufficient that the light source merely be turned on and off for the desired length of time.
  • the sample holder generally designated 7 consists of a slide member having a first section 18 adapted to hold a plurality of sample tubes and a second section 19 which serves as a guide and also as a light barrier. For loading, the holder 7 is moved to the left as is shown in dash-dot lines and a plurality of sample tubes 20 inserted therein. Mounted directly below the sample carrier is a sheet of photographic film 21 and when the slide is to the left, the
  • section 19 prevents any stray light from striking film.
  • the carrier is then moved to the right, as is shown in solid lines in the drawing, and the exposure can be made by the use of the timing mechanism 9 and/or the shutter mechanism 17.
  • the photographic paper 21 may be cut film which is loaded into the usual carrier or, in the embodiment illustrated, it is carried on the rolls and advanced between exposures by means of the knobs 22. After making the exposure, the paper would be removed and developed and fixed in the usual way and would contain a light spot for each sample whose density would correspond with some accepted standard.
  • the selection of the photosensitive material, light filter, light source, time of exposure and type of development would be chosen so that a gray scale matches or has a direct or indirect relationship to the colorimetric optical density of the test samples at a wavelength that is desirable for the tests.
  • ordinary flat bottomed sample cells can be employed or the cells can be as shown in FIG. 2.
  • a holder 17 which holds a sample tube 23, having a convex bottom 25.
  • the bottom of the sample holder acts as a concentrating lens and by placing the photographic paper at the proper distance from the bottom of the tube, a concentration of light is obtained. This gives more accurate results in many instances.
  • the tube itself may also include a filter.
  • the bottom of the cell might be concave for microsamples.
  • FIG. 3 Another embodiment of the invention is illustrated in FIG. 3.
  • a light source 27 is provided with a timer 29 and a condensing lens 31.
  • a filter 33 is provided as well as a vertical sample holder 35.
  • the vertical sample holder contains a number of cells as at 37 each of which preferably has parallel sidewalls although round cells could be used so that the light can be passed sidewise through the panel rather than vertically as waspreviously described.
  • the sample holder 35 fits into a frame 37 shown exploded in FIG. 3.
  • Mounted behind frame 37 is a holder 39 containing a number of photoelectric pickup cells 41.
  • Each cell is connected by suitable wiring, as at 43 to an electronic recording device 45.
  • the electronic recording device can record the results from the photoelectric cells on magnetic tape or the like by scanning the cells. Since the scanning takes place at an extremely high rate of speed compared with the normal color change, a continuous record may be made over a period of time and for all practical purposes, the time will be the same for each of the sample
  • FIGS. 4 and 5 embodiments of the invention are shown wherein an ordinary camera is used to record the densities. It is particularly advantageous to use a camera of the Polaroid type so that the film can be developed and results obtained immediately.
  • the cabinet 5 is equipped with the usual lights 11 and sample slide 7 as previously described and a condensing lens 47 is provided to pick up the light from the bottom of the sample cells and direct it into the lens 49 of camera 51.
  • a condensing lens 47 is provided to pick up the light from the bottom of the sample cells and direct it into the lens 49 of camera 51.
  • FIG. 5 A somewhat similar structure is shown in FIG. 5 but here a series of prisms 53 is employed, one under each sample tube, to direct the parallel rays of light from the bottoms of the sample tubes into the lens 49 of the camera 51.
  • the prisms at the edge will have a greater angle than those near the center and the prisms at the very center will have parallel faces.
  • the prisms could, of course, be built into the sample tubes themselves.
  • fiber optics might be employed or the tubes themselves may be directed toward the camera lens.
  • Modifiers and controls as diffraction gratings, filters, polarizers, lenses, prisms, electromagnetic fields, electromagnetic wave transporting mediums, and/or shutters may be used in the electromagnetic wave pathway between its source and the electromagnetic wave sensitive medium.
  • a multiple colorimeter for obtaining a record of the amount of color or turbidity in a large number of samples simultaneously comprising in combination:
  • said slide having a length of approximately twice the width of said container and being divided into two equal sections including a first section having a plurality of pockets for holding sample tubes and a second section being a blank section whereby said slide can be moved to a first position wherein said blank section intercepts the light from said light source tosaid photographic paper while samples are loaded into said sample section and said slide can then be moved to a second position wherein said samples are interposed between said light source and said photographic paper.

Abstract

A colorimeter or densitometer wherein a number of samples can be read simultaneously. Preferably the instrument incorporates a filter so that the optical density of all samples can be compared on a gray scale. The reading is taken on a photosensitive surface which can be an ordinary photographic paper or a photoelectric cell.

Description

United States Patent [72] Inventor John Victor Komarniski 2167 Burr Ct., Santa Cruz, Calif. 95060 [21] Appl. No. 887,122
[22] Filed [45] Patented Dec. 22, 1969 Dec. 14, 1971 54] DENSITOMETER 1 Claim, Drawing Figs.
52 use 356/180, 250/218, 250/226, 201, 356/208, 356/244,
511 lnt.Cl G01j3/46, 0053/ 50 FieldofSearch 250/435,
[ 56] References Cited UNlTED STATES PATENTS 2,666,854 1/1954 Hutchins 356/181 X 2,725,782 12/1955 Worley 356/208 X 2,866,900 12/1958 250/435 2,942,515 6/1960 Bernardini 356/ 3,503,683 3/1970 lsreeli et a1. 356/181 X 2,427,790 9/1947 Korman 356/185 Primary Examiner-Ronald L. Wibert Assistant Examiner-F. L. Evans Atlorney-Eckhoff and l-loppe ABSTRACT: A colorimeter or densitometer wherein a number of samples can be read simultaneously. Preferably the instrument incorporates a filter so that the optical density of all samples can be compared on a gray scale. The reading is taken on a photosensitive surface which can be an ordinary photographic paper or a photoelectric cell.
PATENTEDUECMIHYI 3,627,431
sum 1 OF 2 INVENTOR.
KOMAKN/SKI ATTOKNEV DENSITOMETER SUMMARY OF THE INVENTION In making many tests wherein color or turbidity of a sample is involved, there frequently is a progressive color change with time. In other words, color indicators or modifiers are often added to sample solutions and there will be a progressive change over a period of time in the color or turbidity. In the past, in preparing dilutions or in adding color indicators, the materials were combined and one waited a certain length of time before a reading was taken on a densitometer or colorimeter. Since individual dilutions were being made, this involved no real problem since the dilutions were made one at a time and the subsequent readings were also taken one at a time so that the interval was substantially the same for each.
However, multiple dilution pipettes have now been developed wherein a large number of samples are simultaneously diluted and/or processed to develop a color in performing tests. In making such tests, there is frequently a progressive change in the color so that for a meaningful comparison to be made between various samples, it is necessary that a colorimetric or densitometric reading be made on all of the samples simultaneously. Obviously if the samples were read one at a time when the dilutions have all been made simultaneously, there would be no uniformity and it would be impossible to make a meaningful comparison of one sample with another or any samples with a standard.
The device of the present invention obviates these difiiculties by providing a densitometer or a colorimeter whereby a large number of samples can be read at the same time. Thus, the results are directly comparable.
BRIEF DESCRIPTION OF THE DRAWINGS In the drawings forming part ofthis application:
FIG. I is a perspective view of an embodiment of the present invention wherein the light passes vertically through the samples and wherein a photographic paper is used as the recording means.
FIG. 2 is an enlarged view of a single sample cell wherein the cell itself incorporates a lens.
FIG. 3 is another embodiment of the invention wherein the light passes horizontally through the samples.
FIG. 4 is a side view in section of a device similar to that shown in FIG. 1 except that an ordinary camera is employed for recording and a condensing lens is used to focus the image ofthe bottom of the cells into the camera lens.
FIG. 5 is a partial view of a device similar to that shown in FIG. 4 except that prisms are employed instead of the condensing lens.
DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to FIG. I, there is shown a colorimeter which is built in the form of a cabinet, generally designated 5, having a sample holder 7 thereon. Mounted on the side ofthe cabinet is a control timer 9 for lights 11. A diffuser I3 is provided so that the light will be uniform on all of the samples. In this embodiment of the invention, the diffuser is a sheet of ground or opal glass. In making many tests, it is necessary to provide a filter 16 which yields a gray scale which is indicative of concentration or the like so that the optical density of the test sample can be determined. Filter 16 is not necessary in all instances.
A shutter mechanism 17 may be employed if desired although this is ordinarily not necessary since it is sufficient that the light source merely be turned on and off for the desired length of time. The sample holder generally designated 7 consists of a slide member having a first section 18 adapted to hold a plurality of sample tubes and a second section 19 which serves as a guide and also as a light barrier. For loading, the holder 7 is moved to the left as is shown in dash-dot lines and a plurality of sample tubes 20 inserted therein. Mounted directly below the sample carrier is a sheet of photographic film 21 and when the slide is to the left, the
section 19 prevents any stray light from striking film. The carrier is then moved to the right, as is shown in solid lines in the drawing, and the exposure can be made by the use of the timing mechanism 9 and/or the shutter mechanism 17.
The photographic paper 21 may be cut film which is loaded into the usual carrier or, in the embodiment illustrated, it is carried on the rolls and advanced between exposures by means of the knobs 22. After making the exposure, the paper would be removed and developed and fixed in the usual way and would contain a light spot for each sample whose density would correspond with some accepted standard. Naturally, the selection of the photosensitive material, light filter, light source, time of exposure and type of development would be chosen so that a gray scale matches or has a direct or indirect relationship to the colorimetric optical density of the test samples at a wavelength that is desirable for the tests.
In the embodiment of the invention illustrated in FIG. 1, ordinary flat bottomed sample cells can be employed or the cells can be as shown in FIG. 2. Here there is shown a holder 17 which holds a sample tube 23, having a convex bottom 25. Thus, the bottom of the sample holder acts as a concentrating lens and by placing the photographic paper at the proper distance from the bottom of the tube, a concentration of light is obtained. This gives more accurate results in many instances. The tube itself may also include a filter. The bottom of the cell might be concave for microsamples.
Another embodiment of the invention is illustrated in FIG. 3. Here, a light source 27 is provided with a timer 29 and a condensing lens 31. A filter 33 is provided as well as a vertical sample holder 35. The vertical sample holder contains a number of cells as at 37 each of which preferably has parallel sidewalls although round cells could be used so that the light can be passed sidewise through the panel rather than vertically as waspreviously described. The sample holder 35 fits into a frame 37 shown exploded in FIG. 3. Mounted behind frame 37 is a holder 39 containing a number of photoelectric pickup cells 41. Each cell is connected by suitable wiring, as at 43 to an electronic recording device 45. The electronic recording device can record the results from the photoelectric cells on magnetic tape or the like by scanning the cells. Since the scanning takes place at an extremely high rate of speed compared with the normal color change, a continuous record may be made over a period of time and for all practical purposes, the time will be the same for each of the sample cells.
In FIGS. 4 and 5, embodiments of the invention are shown wherein an ordinary camera is used to record the densities. It is particularly advantageous to use a camera of the Polaroid type so that the film can be developed and results obtained immediately.
In FIG. 4, the cabinet 5 is equipped with the usual lights 11 and sample slide 7 as previously described and a condensing lens 47 is provided to pick up the light from the bottom of the sample cells and direct it into the lens 49 of camera 51. This provides the advantage that a smaller filter and'film can be used for a given number of sample cells than is the case of FIG. I wherein the film and filter must be of the same size as the area of the total number of sample holders.
A somewhat similar structure is shown in FIG. 5 but here a series of prisms 53 is employed, one under each sample tube, to direct the parallel rays of light from the bottoms of the sample tubes into the lens 49 of the camera 51. Naturally, the prisms at the edge will have a greater angle than those near the center and the prisms at the very center will have parallel faces. Instead of utilizing a separate series of prisms, the prisms could, of course, be built into the sample tubes themselves. Similarly, fiber optics might be employed or the tubes themselves may be directed toward the camera lens.
Although a conventional light source has been illustrated, it is obvious that other forms of electromagnetic waves may be employed such as ultraviolet and infrared rays. Instead of an ordinary filter, one may employ polarizers, diffraction gratings and electromagnetic fields. Other methods can be used to record the intensity of the electromagnetic waves.
The inventor claims as his invention the use of electromagnetic waves passing through many test samples simultaneously for turbidity, density, or color determination, and passing to an electromagnetic wave sensitive medium. Modifiers and controls as diffraction gratings, filters, polarizers, lenses, prisms, electromagnetic fields, electromagnetic wave transporting mediums, and/or shutters may be used in the electromagnetic wave pathway between its source and the electromagnetic wave sensitive medium.
Although certain specific embodiments of the invention have been described, it will be obvious to those skilled in the art that many variations can be made in the exact structure shown without departing from the spirit of this invention.
lclaim:
l. A multiple colorimeter for obtaining a record of the amount of color or turbidity in a large number of samples simultaneously comprising in combination:
a. a generally light tight chamber,
b. a source of light located near the top of said chamber,
c. means for controlling said source of light,
d. a photosensitive photographic paper located near the bottom of said chamber,
e. slots on each side of said chamber, located between said light source and said photographic paper whereby a slide can be passed through said slots intercepting said path of light,
f. a slide adapted to pass through said slots in light tight relationship,
g. said slide having a length of approximately twice the width of said container and being divided into two equal sections including a first section having a plurality of pockets for holding sample tubes and a second section being a blank section whereby said slide can be moved to a first position wherein said blank section intercepts the light from said light source tosaid photographic paper while samples are loaded into said sample section and said slide can then be moved to a second position wherein said samples are interposed between said light source and said photographic paper.
I i '0 il all

Claims (1)

1. A multiple colorimeter for obtaining a record of the amount of color or turbidity in a large number of samples simultaneously comprising in combination: a. a generally light tight chamber, b. a source of light located near the top of said chamber, c. means for controlling said source of light, d. a photosensitive photographic paper located near the bottom of said chamber, e. slots on each side of said chamber, located between said light source and said photographic paper whereby a slide can be passed through said slots intercepting said path of light, f. a slide adapted to pass through said slots in light tight relationship, g. said slide having a length of approximately twice the width of said container and being divided into two equal sections including a first section having a plurality of pockets for holding sample tubes and a second section being a blank section whereby said slide can be moved to a first position wherein said blank section intercepts the light from said light source to said photographic paper while samples are loaded into said sample section and said slide can then be moved to a second position wherein said samples are interposed between said light source and said photographic paper.
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US3773426A (en) * 1972-02-22 1973-11-20 Department Of Health Educ Welf Bacterial growth detector
US3837746A (en) * 1972-09-20 1974-09-24 Akro Medic Eng Corp Apparatus for evaluation of biological fluid
US3837745A (en) * 1972-09-20 1974-09-24 Akro Medic Eng Corp Apparatus for evaluation of biological fluid
USRE28800E (en) * 1972-09-20 1976-05-04 Akro-Medic Engineering, Inc. Apparatus for evaluation of biological fluid
USRE28801E (en) * 1972-09-20 1976-05-04 Akro-Medic Engineering, Inc. Apparatus for evaluation of biological fluid
US3999863A (en) * 1975-08-13 1976-12-28 Rohr Industries, Inc. Apparatus for measuring light absorption
US4115010A (en) * 1976-02-03 1978-09-19 Merck & Co., Inc. Automated plate reader
WO1982000356A1 (en) * 1980-07-24 1982-02-04 Oy Labsystems Analyzer
WO1982000357A1 (en) * 1980-07-24 1982-02-04 Oy Labsystems Method and apparatus for the measurement of the properties of an agglutination
WO1982000358A1 (en) * 1980-07-24 1982-02-04 Oy Labsystems Method of measurement and a cuvette
US4448534A (en) * 1978-03-30 1984-05-15 American Hospital Corporation Antibiotic susceptibility testing
WO1984002090A1 (en) * 1982-11-20 1984-06-07 Thomas Paterson Whitehead Dispensing device and recording apparatus
US4456380A (en) * 1980-08-01 1984-06-26 Fujisawa Pharmaceutical Co., Ltd. Test system for identifying bacteria
US4657870A (en) * 1984-04-23 1987-04-14 Ryder International Corporation Incubator optical system for viewing sterilization indicator
US4784947A (en) * 1980-07-10 1988-11-15 Noeller Hans Guenter Flash-photometer for nephelometric determinations
US4799599A (en) * 1982-07-30 1989-01-24 Ciba Corning Diagnostics Corp. Specimen cup and cap assembly for clinical analyzer
US4892409A (en) * 1988-07-14 1990-01-09 Smith Harry F Photometric apparatus for multiwell plates having a positionable lens assembly
WO1996013708A1 (en) * 1994-10-28 1996-05-09 Moxtek, Inc. Thin film sample support
US5912737A (en) * 1998-06-01 1999-06-15 Hach Company System for verifying the calibration of a turbidimeter
US6043880A (en) * 1997-09-15 2000-03-28 Becton Dickinson And Company Automated optical reader for nucleic acid assays
US6157445A (en) * 1992-01-07 2000-12-05 Chromatics Color Sciences International, Inc. Method and apparatus for detecting and measuring conditions affecting color
US6271920B1 (en) 1997-12-19 2001-08-07 Chromatics Color Sciences International, Inc. Methods and apparatus for color calibration and verification
US6308088B1 (en) 1992-01-07 2001-10-23 Chromatics Color Sciences International, Inc. Method and apparatus for detecting and measuring conditions affecting color
US6447120B2 (en) 1999-07-28 2002-09-10 Moxtex Image projection system with a polarizing beam splitter
US6597450B1 (en) 1997-09-15 2003-07-22 Becton, Dickinson And Company Automated Optical Reader for Nucleic Acid Assays
US6666556B2 (en) 1999-07-28 2003-12-23 Moxtek, Inc Image projection system with a polarizing beam splitter
US6710921B2 (en) 1998-05-14 2004-03-23 Moxtek Polarizer apparatus for producing a generally polarized beam of light
US6785050B2 (en) 2002-05-09 2004-08-31 Moxtek, Inc. Corrosion resistant wire-grid polarizer and method of fabrication
US6788414B1 (en) * 1999-09-09 2004-09-07 Iowa State University Research Foundation, Inc. Method of analyzing multiple sample simultaneously by detecting absorption and systems for use in such a method
US7184115B2 (en) 2002-01-07 2007-02-27 Moxtek, Inc. Display apparatus with two polarization compensators
US7221420B2 (en) 2002-01-07 2007-05-22 Sony Corporation Display with a wire grid polarizing beamsplitter
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US7375887B2 (en) 2001-03-27 2008-05-20 Moxtek, Inc. Method and apparatus for correcting a visible light beam using a wire-grid polarizer
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US8755113B2 (en) 2006-08-31 2014-06-17 Moxtek, Inc. Durable, inorganic, absorptive, ultra-violet, grid polarizer
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Cited By (63)

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Publication number Priority date Publication date Assignee Title
US3773426A (en) * 1972-02-22 1973-11-20 Department Of Health Educ Welf Bacterial growth detector
US3837746A (en) * 1972-09-20 1974-09-24 Akro Medic Eng Corp Apparatus for evaluation of biological fluid
US3837745A (en) * 1972-09-20 1974-09-24 Akro Medic Eng Corp Apparatus for evaluation of biological fluid
USRE28800E (en) * 1972-09-20 1976-05-04 Akro-Medic Engineering, Inc. Apparatus for evaluation of biological fluid
USRE28801E (en) * 1972-09-20 1976-05-04 Akro-Medic Engineering, Inc. Apparatus for evaluation of biological fluid
US3999863A (en) * 1975-08-13 1976-12-28 Rohr Industries, Inc. Apparatus for measuring light absorption
US4115010A (en) * 1976-02-03 1978-09-19 Merck & Co., Inc. Automated plate reader
US4448534A (en) * 1978-03-30 1984-05-15 American Hospital Corporation Antibiotic susceptibility testing
US4784947A (en) * 1980-07-10 1988-11-15 Noeller Hans Guenter Flash-photometer for nephelometric determinations
WO1982000356A1 (en) * 1980-07-24 1982-02-04 Oy Labsystems Analyzer
WO1982000357A1 (en) * 1980-07-24 1982-02-04 Oy Labsystems Method and apparatus for the measurement of the properties of an agglutination
WO1982000358A1 (en) * 1980-07-24 1982-02-04 Oy Labsystems Method of measurement and a cuvette
US4456380A (en) * 1980-08-01 1984-06-26 Fujisawa Pharmaceutical Co., Ltd. Test system for identifying bacteria
US4799599A (en) * 1982-07-30 1989-01-24 Ciba Corning Diagnostics Corp. Specimen cup and cap assembly for clinical analyzer
EP0110610A2 (en) * 1982-11-20 1984-06-13 The University Of Birmingham Dispensing device and recording apparatus
US4593728A (en) * 1982-11-20 1986-06-10 Whitehead Thomas P Dispensing device and recording apparatus
GB2169704A (en) * 1982-11-20 1986-07-16 Thomas Paterson Whitehead Test reaction result recording apparatus
EP0207532A2 (en) * 1982-11-20 1987-01-07 The University Of Birmingham Recording Apparatus
EP0207532A3 (en) * 1982-11-20 1987-07-01 Thomas Paterson Whitehead Recording apparatus
AU567440B2 (en) * 1982-11-20 1987-11-19 Thomas Paterson Whitehead Dispensing device and recording apparatus
EP0110610A3 (en) * 1982-11-20 1984-09-12 Thomas Paterson Whitehead Dispensing device and recording apparatus
WO1984002090A1 (en) * 1982-11-20 1984-06-07 Thomas Paterson Whitehead Dispensing device and recording apparatus
US4879097A (en) * 1982-11-20 1989-11-07 Whitehead Thomas P Dispensing device and recording apparatus
US4657870A (en) * 1984-04-23 1987-04-14 Ryder International Corporation Incubator optical system for viewing sterilization indicator
US4892409A (en) * 1988-07-14 1990-01-09 Smith Harry F Photometric apparatus for multiwell plates having a positionable lens assembly
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