US3603689A - Scanning scattered light photometer - Google Patents
Scanning scattered light photometer Download PDFInfo
- Publication number
- US3603689A US3603689A US865899A US3603689DA US3603689A US 3603689 A US3603689 A US 3603689A US 865899 A US865899 A US 865899A US 3603689D A US3603689D A US 3603689DA US 3603689 A US3603689 A US 3603689A
- Authority
- US
- United States
- Prior art keywords
- output
- light
- polarizer
- rotor
- signal
- 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 - Lifetime
Links
- 238000012935 Averaging Methods 0.000 claims abstract description 21
- 239000000443 aerosol Substances 0.000 claims abstract description 17
- 230000000007 visual effect Effects 0.000 claims 1
- 238000001228 spectrum Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 238000000149 argon plasma sintering Methods 0.000 description 1
- 230000015271 coagulation Effects 0.000 description 1
- 238000005345 coagulation Methods 0.000 description 1
- 238000001246 colloidal dispersion Methods 0.000 description 1
- 239000000084 colloidal system Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- CPBQJMYROZQQJC-UHFFFAOYSA-N helium neon Chemical compound [He].[Ne] CPBQJMYROZQQJC-UHFFFAOYSA-N 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
Images
Classifications
-
- 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
- G01N21/21—Polarisation-affecting properties
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/02—Investigating particle size or size distribution
- G01N15/0205—Investigating particle size or size distribution by optical means
-
- 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
- G01N21/47—Scattering, i.e. diffuse reflection
- G01N21/49—Scattering, i.e. diffuse reflection within a body or fluid
- G01N21/53—Scattering, i.e. diffuse reflection within a body or fluid within a flowing fluid, e.g. smoke
-
- 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
- G01N21/47—Scattering, i.e. diffuse reflection
- G01N2021/4792—Polarisation of scatter light
Definitions
- a polarizing beamsplitter on the rotor separates the scattered light into two perpendicular components.
- a first mirror on the rotor directs a first polarized component of light in the plane of rotation of the rotor toward a first photomultiplier.
- a second mirror on the rotor directs light polarized perpendicular to the plane of rotation toward a second photomultiplier.
- a fixed mirror directs undispersed light toward a photoconductive device to provide a synchronizing output pulse when the polarizer beamsplitter passes through the beam between the light source and the aerosol flow.
- the outputs of the photomultipliers and photoconductive device are fed to a ratio and averaging circuit and then to a recorder.
- an apparatus that substantially reduces the time required to obtain data from a sample and which provides more complete data than could be obtained with prior art methods.
- a collimated, monochromatic unpolarized light source is positioned to impinge a beam of light on an aerosol sample in a space between an entrance nozzle and a vacuum exhaust outlet.
- the sample flows through the center of a hub around which a scanner rotates.
- a polarizing prism and two mirrors are mounted on the scanner. The mirrors direct the two polarized components of the light scattered by the sample to two photomultipliers positioned above the center of the scanner.
- the outputs of the photomultipliers are fed to an analog divider circuit and signal averaging circuit with the output of the signal averaging circuit being applied to a display device and a recorder.
- a sync signal for the signal averager may be provided if needed.
- FIG. 1 is a schematic diagram partially in block form of a scanning scattered light photometer system according to the invention
- FIG. 2 is a partially cutaway front elevation of the scanning apparatus for the device of FIG. 1;
- FIG. 3 is a sectional view of the device of FIG. 2 along the line 33;
- FIG. 4 is a top view of the rotor assembly for the device of FIG. 2.
- FIG. 1 of the drawing shows a scattered light photometric system including a scanning apparatus 12 shown in greater detail in FIGS. 2-4.
- the scanning apparatus 12 includes a chamber 14.
- a sample to be tested is supplied to a nozzle in the center of chamber 14 from sample supply 16.
- the flow leaving nozzle 15 is directed toward an exhaust outlet 17 which leads to a vacuum source, not shown.
- a beam of collimated, monochromatic un polarized light is directed toward the sample from a light source 19.
- the light is scattered by the particles of the sample leaving the nozzle 15.
- a rotor 20 has a hub 22 surrounding the exhaust outlet 17.
- the rotor 20 is driven by a motor 24 through a gear train 25.
- a polarizing beamsplitter 27 is mounted on the rotor 20. As the scanner is rotated, the light scattered at any particular angle is received by a slot 30 in a mask 31 positioned in front of the polarizing beamsplitter 27. Light polarized in the plane of rotation of the polarizer on the scanner is reflected by a precision front surface mirror 32 toward photomultiplier 33. Light polarized in the plane perpendicular to the plane of rotation is reflected by a precision front surface mirror through a slot 34 in rotor 20 toward a photomultiplier 36. A counterbalance 37 for the beamsplitter 27 and mirrors 32 and 35 is provided on rotor 20. A
- beamsplitter 27 may be a Spectra Physics Model 5115 polarizing beamsplitter and the mirrors 32 and 35 may be Spectra Physics Model 576-4l front surface mirrors.
- the light source 19 may be a Spectra Physics Model 132 l-milliwatt heliumneon laser.
- the output of photomultipliers 33 and 36 are passed through preamplifiers 40 and 42 and then to an analog divider 46 which provides an output A/B.
- the analog divider as may be, for example, a Princeton Applied Research Co. Model 230.
- the output of the analog divider 46 is then supplied to a signal averaging circuit ltl which may be, for example, the Princeton Applied Research Co. Model TDH-9 Waveform Eductor.
- the signal averaging circuit divides the signal waveform into segments continuously samples and averages each segment and provides in the output a smooth waveform based on these averages which is substantially free of noise.
- a device which performs the function of both the analog divider 46 and the signal averaging circuit 48 is the Fabri-Telc I070 signal averaging computer.
- the output of the signal averaging circuit 48 is applied to either a recorder such as an oscillograph 51 or to a display device such as an oscil loscope 52.
- the output of the photomultipliers 33 and 36 may be used in other circuits than that described, for example, they could be supplied to a circuit to provide an output A-B/A+B or other outputs as may be desired.
- this signal may be obtained by providing a stationary mirror 55 mounted on flange 18 on outlet 17 which directs unscattered light to a photoconductor 56. This light is blocked from the mirror and photoconductor whenever the polarizer 47 and mirrors 32 and 35 pass the side of the chamber I4 ad jacent the light source 19 and thus provides a synchronizing pulse to the averaging circuit 48. Since light scattered by the sample is the same on both sides of the beam, an output is needed for only of the rotation of the rotor.
- a shield 53 having a semicircular opening 59 blocks light from mirrors 32 and 35 to photomultipliers 33 and 36 during half of the rotation. This could also be accomplished electronically by means of a gate circuit which provides a gate pulse for the desired period to be observed by the waveform averages in response to the output from the photoconductor 56. Power is supplied to the various devices from a power supply 60.
- a device for providing an output signal proportional to the two polarized components of light scattered by a flowing aerosol for all angular positions in a predetermined 180 region around the flowing aerosol comprising: means for providing a sample flow; means for directing a beam of collimated monochromatic unpolarized light toward said flow; a beamsplitter polarizer; an apertured mask between said beamsplitter polarizer and said sample flow; means for moving said mask and said polarizer in a circular path around said sample flow; a first photomultiplier tube; means for directing a first polarized component of light scattered by the flowing aerosol, in the plane of said circular path, toward said first photomultiplier tube; a second photomultiplier scattered by the flowing aerosol, perpendicular to the plane of said circular path, toward said second photomultiplier tube; means responsive to the output of said photomultipliers for providing an output signal proportional to the output of the first photomultiplier tube and the second photomultiplier tube.
- said means for providing an output signal includes an analog divider means for providing a signal proportional to the ratio of the output of said first photomultiplier and the output of said second photomultiplier; a signal averaging circuit connected to the output of said analog divider means; means for supplying a signal to said signal averaging circuit for synchronizing the the polarizer includes a photovoltaic cell; a stationary mirror positioned in line with the beam of collimated monochromatic unpolarizcd light; said means for moving said polarizer in a circular path being a rotor for moving the polarizer into the light beam path once during each revolution of the rotor to block light to said stationary mirror and photovoltaic cell to thereby provide a synchronizing signal for said averaging circuit.
Landscapes
- Chemical & Material Sciences (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Dispersion Chemistry (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
A scanning scattered light photometer system having a rotor with a beamsplitter-polarizer and a nozzle for directing an aerosol flow along the axis of the rotor toward an exhaust outlet. The aerosol flow is illuminated by a collimated monochromatic unpolarized light. A polarizing beamsplitter on the rotor separates the scattered light into two perpendicular components. A first mirror on the rotor directs a first polarized component of light in the plane of rotation of the rotor toward a first photomultiplier. A second mirror on the rotor directs light polarized perpendicular to the plane of rotation toward a second photomultiplier. A fixed mirror directs undispersed light toward a photoconductive device to provide a synchronizing output pulse when the polarizer beamsplitter passes through the beam between the light source and the aerosol flow. The outputs of the photomultipliers and photoconductive device are fed to a ratio and averaging circuit and then to a recorder.
Description
United States Patent lnventor James William Shelnutt, 111
Dayton, Ohio [21 1 Appl. No. 865,899 [22] Filed Oct. 13, 1969 [45] Patented Sept. 7, 1971 [73] Assignee The United States of America as represented by the Secretary of the Air Force I E [54] SCANNING SCATTERED LIGHT PHOTOMETER 5 Claims, 4 Drawing Figs.
[52] US. Cl. 356/103, 356/1 14 [51] Int. Cl G0ln21/00, G0 1 n 21/40 [50] Field oiSearch 356/103, 104, 1 l4, 1 15 [56] References Cited UNITED STATES PATENTS 3,334,537 8/1967 Beattie 3,420,609 1/1969 Kozawa ABSTRACT: A scanning scattered light photometer system having a rotor with a beamsplitter-polarizer and a nozzle for directing an aerosol flow along the axis of the rotor toward an exhaust outlet. The aerosol flow is illuminated by a collimated monochromatic unpolarized light. A polarizing beamsplitter on the rotor separates the scattered light into two perpendicular components. A first mirror on the rotor directs a first polarized component of light in the plane of rotation of the rotor toward a first photomultiplier. A second mirror on the rotor directs light polarized perpendicular to the plane of rotation toward a second photomultiplier. A fixed mirror directs undispersed light toward a photoconductive device to provide a synchronizing output pulse when the polarizer beamsplitter passes through the beam between the light source and the aerosol flow. The outputs of the photomultipliers and photoconductive device are fed to a ratio and averaging circuit and then to a recorder.
PATENTEDSEP m 33,603,689
SHEET 2 [IF 4 PATENIEDSEP 71971 $603,689
sum 3 BF 4 PATENTEDSEP mm SHEET t 0F 4 INVENTOR.
SCANNING SCATTERED LIGI-IT PlIIOTOME'IER BACKGROUND OF THE INVENTION In the study of aerosols, colloidal dispersions, and other particulate suspensions the particle size distribution is obtained by the polarization ratio method as is described in the article "Aerosol Studies by Light Scattering" in The Journal of Colloid Science, Vol. 19, 1964, pp. 21 3-222.
In the prior art, data is obtained in a point-by-point system. This is very time consuming and limits the type of samples from which data may be obtained. Since data must be obtained by moving from point to point to different angular positions around the sample there is a considerable time lag between the obtaining of the initial and the final data. In samples wherein changes are occurring, such as coagulation, this time lag seriously limits the data obtainable from the sample.
SUMMARY OF THE INVENTION According to this invention, an apparatus is provided that substantially reduces the time required to obtain data from a sample and which provides more complete data than could be obtained with prior art methods. A collimated, monochromatic unpolarized light source is positioned to impinge a beam of light on an aerosol sample in a space between an entrance nozzle and a vacuum exhaust outlet. The sample flows through the center of a hub around which a scanner rotates. A polarizing prism and two mirrors are mounted on the scanner. The mirrors direct the two polarized components of the light scattered by the sample to two photomultipliers positioned above the center of the scanner. The outputs of the photomultipliers are fed to an analog divider circuit and signal averaging circuit with the output of the signal averaging circuit being applied to a display device and a recorder. A sync signal for the signal averager may be provided if needed.
IN THE DRAWING FIG. 1 is a schematic diagram partially in block form of a scanning scattered light photometer system according to the invention;
FIG. 2 is a partially cutaway front elevation of the scanning apparatus for the device of FIG. 1;
FIG. 3 is a sectional view of the device of FIG. 2 along the line 33; and
FIG. 4 is a top view of the rotor assembly for the device of FIG. 2.
DETAILED DESCRIPTION OF THE INVENTION Reference is now made to FIG. 1 of the drawing which shows a scattered light photometric system including a scanning apparatus 12 shown in greater detail in FIGS. 2-4. The scanning apparatus 12 includes a chamber 14. A sample to be tested is supplied to a nozzle in the center of chamber 14 from sample supply 16. The flow leaving nozzle 15 is directed toward an exhaust outlet 17 which leads to a vacuum source, not shown. A beam of collimated, monochromatic un polarized light is directed toward the sample from a light source 19. The light is scattered by the particles of the sample leaving the nozzle 15. A rotor 20 has a hub 22 surrounding the exhaust outlet 17. The rotor 20 is driven by a motor 24 through a gear train 25. A polarizing beamsplitter 27 is mounted on the rotor 20. As the scanner is rotated, the light scattered at any particular angle is received by a slot 30 in a mask 31 positioned in front of the polarizing beamsplitter 27. Light polarized in the plane of rotation of the polarizer on the scanner is reflected by a precision front surface mirror 32 toward photomultiplier 33. Light polarized in the plane perpendicular to the plane of rotation is reflected by a precision front surface mirror through a slot 34 in rotor 20 toward a photomultiplier 36. A counterbalance 37 for the beamsplitter 27 and mirrors 32 and 35 is provided on rotor 20. A
The output of photomultipliers 33 and 36 are passed through preamplifiers 40 and 42 and then to an analog divider 46 which provides an output A/B. The analog divider as may be, for example, a Princeton Applied Research Co. Model 230. The output of the analog divider 46 is then supplied to a signal averaging circuit ltl which may be, for example, the Princeton Applied Research Co. Model TDH-9 Waveform Eductor. The signal averaging circuit divides the signal waveform into segments continuously samples and averages each segment and provides in the output a smooth waveform based on these averages which is substantially free of noise. A device which performs the function of both the analog divider 46 and the signal averaging circuit 48 is the Fabri-Telc I070 signal averaging computer. The output of the signal averaging circuit 48 is applied to either a recorder such as an oscillograph 51 or to a display device such as an oscil loscope 52.
The output of the photomultipliers 33 and 36 may be used in other circuits than that described, for example, they could be supplied to a circuit to provide an output A-B/A+B or other outputs as may be desired.
When a synchronizing signal is needed such as in averaging corresponding parts of a signal, as in signal averaging circuit 48, this signal may be obtained by providing a stationary mirror 55 mounted on flange 18 on outlet 17 which directs unscattered light to a photoconductor 56. This light is blocked from the mirror and photoconductor whenever the polarizer 47 and mirrors 32 and 35 pass the side of the chamber I4 ad jacent the light source 19 and thus provides a synchronizing pulse to the averaging circuit 48. Since light scattered by the sample is the same on both sides of the beam, an output is needed for only of the rotation of the rotor. A shield 53 having a semicircular opening 59 blocks light from mirrors 32 and 35 to photomultipliers 33 and 36 during half of the rotation. This could also be accomplished electronically by means of a gate circuit which provides a gate pulse for the desired period to be observed by the waveform averages in response to the output from the photoconductor 56. Power is supplied to the various devices from a power supply 60.
There is thus provided a scanning scattered light photometer system which provides more complete data and substantially reduces the time required to obtain data.
I claim:
I. A device for providing an output signal proportional to the two polarized components of light scattered by a flowing aerosol for all angular positions in a predetermined 180 region around the flowing aerosol comprising: means for providing a sample flow; means for directing a beam of collimated monochromatic unpolarized light toward said flow; a beamsplitter polarizer; an apertured mask between said beamsplitter polarizer and said sample flow; means for moving said mask and said polarizer in a circular path around said sample flow; a first photomultiplier tube; means for directing a first polarized component of light scattered by the flowing aerosol, in the plane of said circular path, toward said first photomultiplier tube; a second photomultiplier scattered by the flowing aerosol, perpendicular to the plane of said circular path, toward said second photomultiplier tube; means responsive to the output of said photomultipliers for providing an output signal proportional to the output of the first photomultiplier tube and the second photomultiplier tube.
2. The device as recited in claim I wherein said means for providing an output signal includes an analog divider means for providing a signal proportional to the ratio of the output of said first photomultiplier and the output of said second photomultiplier; a signal averaging circuit connected to the output of said analog divider means; means for supplying a signal to said signal averaging circuit for synchronizing the the polarizer includes a photovoltaic cell; a stationary mirror positioned in line with the beam of collimated monochromatic unpolarizcd light; said means for moving said polarizer in a circular path being a rotor for moving the polarizer into the light beam path once during each revolution of the rotor to block light to said stationary mirror and photovoltaic cell to thereby provide a synchronizing signal for said averaging circuit.
Claims (5)
1. A device for providing an output signal proportional to the two polarized components of light scattered by a flowing aerosol for all angular positions in a predetermined 180* region around the flowing aerosol comprising: means for providing a sample flow; means for directing a beam of collimated monochromatic unpolarized light toward said flow; a beamsplitter polarizer; an apertured mask between said beamsplitter polarizer and said sample flow; means for moving said mask and said polarizer in a circular path around said sample flow; a first photomultiplier tube; means for directing a first polarized component of light scattered by the flowing aerosol, in the plane of said circular path, toward said first photomultiplier tube; a second photomultiplier scattered by the flowing aerosol, perpendicular to the plane of said circular path, toward said second photomultiplier tube; means responsive to the output of said photomultipliers for providing an output signal proportional to the output of the first photomultiplier tube and the second photomultiplier tube.
2. The device as recited in claim 1 wherein said means for providing an output signal includes an analog divider means for providing a signal proportional to the ratio of the output of said first photomultiplier and the output of said second photomultiplier; a signal averaging circuit connected to the output of said analog divider means; means for supplying a signal to said signal averaging circuit for synchronizing the signal averaging circuit with the rotation of the polarizer in said circular path; an output circuit connected to said signal averaging circuit.
3. The device as recited in claim 2 wherein said output circuit includes a recorder.
4. The device as recited in claim 2 wherein said output circuit includes a visual display device.
5. The device as recited in claim 2 wherein said means for synchronizing the signal averaging circuit with the rotation of the polarizer includes a photovoltaic cell; a stationary mirror positioned in line with the beam of collimated monochromatic unpolarized light; said means for moving said polarizer in a circular path being a rotor for moving the polarizer into the light beam path once during each revolution of the rotor to block light to said stationary mirror and photovoltaic cell to thereby provide a synchronizing signal for said averaging circuit.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US86589969A | 1969-10-13 | 1969-10-13 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3603689A true US3603689A (en) | 1971-09-07 |
Family
ID=25346484
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US865899A Expired - Lifetime US3603689A (en) | 1969-10-13 | 1969-10-13 | Scanning scattered light photometer |
Country Status (1)
Country | Link |
---|---|
US (1) | US3603689A (en) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3724951A (en) * | 1971-08-31 | 1973-04-03 | Eastman Kodak Co | Method and apparatus for determining radiation transmission characteristics of a generally transparent medium |
US3879615A (en) * | 1972-11-09 | 1975-04-22 | Kernforschung Gmbh Ges Fuer | Method and apparatus for the rapid measuring of the angular dependence of scattered light |
US4134679A (en) * | 1976-11-05 | 1979-01-16 | Leeds & Northrup Company | Determining the volume and the volume distribution of suspended small particles |
US4362387A (en) * | 1980-08-22 | 1982-12-07 | Rockwell International Corporation | Method and apparatus for measuring visibility from the polarization properties of the daylight sky |
US4662742A (en) * | 1985-05-10 | 1987-05-05 | Becton, Dickinson And Company | Scatter/fluorescene beam splitter in a flow cytometry apparatus |
US4885473A (en) * | 1988-04-29 | 1989-12-05 | Shofner Engineering Associates, Inc. | Method and apparatus for detecting particles in a fluid using a scanning beam |
EP1588147A2 (en) * | 2003-01-24 | 2005-10-26 | Beckman Coulter, Inc. | Extracted polarization intensity differential scattering for particle characterization |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3283644A (en) * | 1962-11-27 | 1966-11-08 | Du Pont | Apparatus for determining the concentration of dispersed particulate solids in liquids |
US3334537A (en) * | 1963-04-29 | 1967-08-08 | Beckman Instruments Inc | Light scattering attachment |
US3420609A (en) * | 1964-08-27 | 1969-01-07 | Shimadzu Corp | Photometer for comparing scattered with transmitted light |
-
1969
- 1969-10-13 US US865899A patent/US3603689A/en not_active Expired - Lifetime
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3283644A (en) * | 1962-11-27 | 1966-11-08 | Du Pont | Apparatus for determining the concentration of dispersed particulate solids in liquids |
US3334537A (en) * | 1963-04-29 | 1967-08-08 | Beckman Instruments Inc | Light scattering attachment |
US3420609A (en) * | 1964-08-27 | 1969-01-07 | Shimadzu Corp | Photometer for comparing scattered with transmitted light |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3724951A (en) * | 1971-08-31 | 1973-04-03 | Eastman Kodak Co | Method and apparatus for determining radiation transmission characteristics of a generally transparent medium |
US3879615A (en) * | 1972-11-09 | 1975-04-22 | Kernforschung Gmbh Ges Fuer | Method and apparatus for the rapid measuring of the angular dependence of scattered light |
US4134679A (en) * | 1976-11-05 | 1979-01-16 | Leeds & Northrup Company | Determining the volume and the volume distribution of suspended small particles |
US4362387A (en) * | 1980-08-22 | 1982-12-07 | Rockwell International Corporation | Method and apparatus for measuring visibility from the polarization properties of the daylight sky |
US4662742A (en) * | 1985-05-10 | 1987-05-05 | Becton, Dickinson And Company | Scatter/fluorescene beam splitter in a flow cytometry apparatus |
US4885473A (en) * | 1988-04-29 | 1989-12-05 | Shofner Engineering Associates, Inc. | Method and apparatus for detecting particles in a fluid using a scanning beam |
EP1588147A2 (en) * | 2003-01-24 | 2005-10-26 | Beckman Coulter, Inc. | Extracted polarization intensity differential scattering for particle characterization |
EP1588147A4 (en) * | 2003-01-24 | 2011-09-28 | Beckman Coulter Inc | Extracted polarization intensity differential scattering for particle characterization |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4919536A (en) | System for measuring velocity field of fluid flow utilizing a laser-doppler spectral image converter | |
US3866055A (en) | Laser doppler velocimetry | |
US3941477A (en) | Measuring device for the measurement of fluid flow rates | |
US3603689A (en) | Scanning scattered light photometer | |
US4097153A (en) | Method and apparatus for measuring the electrophoretic mobility of suspended particles | |
GB1168005A (en) | A Method of and Apparatus for Determining Geometrical Deviations from a Desired Surface by Optical Means | |
GB1242574A (en) | A method of, and apparatus for, inspecting the shape of small objects | |
US4140902A (en) | Device for measurement of hair-like particulate material | |
GB1414038A (en) | Method and apparatus for measuring the turbidity of fluids | |
Gucker et al. | Rapid measurement of light-scattering diagrams from single particles in an aerosol stream and determination of latex particle size | |
US3832059A (en) | Flow velocity measuring arrangement utilizing laser doppler probe | |
US2817769A (en) | Radiation comparison systems | |
GB1000286A (en) | Light scattering measuring apparatus | |
GB1361736A (en) | Device for analysing a substance by atomic absorption with back ground correction | |
JPS58153107A (en) | Device for measuring diameter and speed of particle simultaneously | |
US3488122A (en) | Process for determining the spectral composition of luminous radiation diffused by a colored surface,and apparatus for carrying out said process | |
Karns | Development of a laser doppler velocimetry system for supersonic jet turbulence measurements | |
Sauer | Molecular Orientation in Quantasomes: III. A Flow Dichroism Apparatus and Its Application to the Study of the Structure of Spinach Quantasomes | |
GB1353582A (en) | Instruments for analysing substances by determining their radiation absorption characteristics | |
GB1370967A (en) | Multi-angle beam director for testing aperture masks | |
US3630621A (en) | Measurement of visibility through a fluid using polarized light | |
US3667851A (en) | Measuring system for an analytical centrifuge | |
Kabardin et al. | Kinematic characteristics investigation in a transparent swirler of a vortex tube with square cross-section | |
GB1019540A (en) | A method and apparatus for determining the difference in area of an article from an article of known area | |
JP3049926B2 (en) | Particle size distribution analyzer |