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US4420257A Expired / Lapsed US ⏱️ 0.0 years remaining

Laser light scattering photometer

Assignee: Tosoh Corp
•
Filing: 1980-02-14
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Granted: 1983-12-13
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Expires: 2000-02-14
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Abstract

Abstract A laser light beam is projected through a fluid measuring cell having a fluid accommodating chamber and inlet and outlet pathways for the fluid. The light is separated into transmitted light and scattered light. Separate light detectors sense the transmitted light and scattered light. An electric control circuit uses the variations of the intensity of the transmitted light to compensate for fluctuations in the intensity of the scattered light to provide an output related to the intensity of the scattered light.

Inventors

  • 👤 Mitsutoshi Fukuda
  • 👤 Nobuyuki Baba
  • 👤 Kenji Arichika

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 18:10
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/47; G01N21/49; G01N21/53; G01N21/532

Claims Analysis

Total Claims: 29
Claim 1
Independent Claim 269 words
An apparatus for measuring the intensity of light scattered by a test fluid comprising: means for providing a light beam, measuring cell means having a chamber for accommodating test fluid, said chamber of the measuring cell means being aligned with the optical axis of the light beam whereby the light beam passes through the test fluid as transmitted light and scattered light, means having an annular slit located adjacent the measuring cell means aligned to match the axis of the scattered light, first light detector means operable to monitor the intensity of scattered light passing through said annular slit, second light detector means operable to monitor the intensity of the transmitted light, and electronic circuit means connected to said first and second light detector means operable to use variations of the intensity of the transmitted light to compensate for fluctuations of the intensity of the scattered light to provide an output related to the intensity of the scattered light, said electronic circuit means includes first amplifier means connected to the output of the second light detector means, second amplifier means connected to the output of the first amplifier means, reference voltage means connected to the second amplifier means providing the second amplifier means with a reference voltage, and power supply means connected to the output of the second amplifier means, said power supply means having an output related to the output of the second amplifier means and connected to the input of the first light detector means whereby variations of the scattered light are compensated by the variations of the transmitted light detected by the second light detector means.
Claim 2
Independent Claim 269 words
An apparatus for measuring the intensity of light scattered by a test fluid comprising: means for providing a light beam, measuring cell means having a chamber for accommodating test fluid, said chamber of the measuring cell means being aligned with the optical axis of the light beam whereby the light beam passes through the test fluid as transmitted light and scattered light, means having an annular slit located adjacent the measuring cell means aligned to match the axis of the scattered light, first light detector means operable to monitor the intensity of scattered light passing through said annular slit, second light detector means operable to monitor the intensity of the transmitted light, and electronic circuit means connected to said first and second light detector means operable to use variations of the intensity of the transmitted light to compensate for fluctuations of the intensity of the scattered light to provide an output related to the intensity of the scattered light, said electronic circuit means includes first amplifier means connected to the output of the second light detector means, second amplifier means connected to the output of the first amplifier means, reference voltage means connected to the second amplifier means providing the second amplifier means with a reference voltage, and power supply means connected to the output of the second amplifier means, said power supply means having an output related to the output of the second amplifier means and connected to the input of the first light detector means whereby variations of the scattered light are compensated by the variations of the transmitted light detected by the second light detector means.
Claim 3
Dependent Claim 48 words
The apparatus of claim 1 wherein: said measuring cell means includes an inlet pathway connected to the chamber for carrying test fluid to the chamber, and an outlet pathway connected to the chamber for carrying test fluid from the chamber whereby said test fluid flows through said chamber.
Claim 4
Dependent Claim 27 words
The apparatus of claim 2 wherein: the measuring cell means includes a portion made of non-light reflecting material, said portion having said inlet pathway and outlet pathway.
Claim 5
Dependent Claim 61 words
The apparatus of claim 1 wherein: the measuring cell means includes a body having a central chamber, an inlet pathway open to one side of the chamber, and an outlet pathway open to the other side of the chamber, said chamber and inlet and outlet pathways accommodating flowing test fluid, and glass block means secured to opposite sides of the body.
Claim 6
Dependent Claim 14 words
The apparatus of claim 4 wherein: said body is made of non-light reflecting material.
Claim 7
Dependent Claim 15 words
The apparatus of claim 1 wherein: the first light detector means comprises a photomultiplier tube.
Claim 8
Independent Claim 17 words
The apparatus of claims 1 or 6 wherein: the second light detector means comprises a photomultiplier tube.
Claim 9
Independent Claim 17 words
The apparatus of claims 1 or 6 wherein: the second light detector means comprises a photomultiplier tube.
Claim 10
Dependent Claim 31 words
The apparatus of claim 1 including: lens means between the means having an annular slit and the first light means for directing the scattered light to the first light detector means.
Claim 11
Dependent Claim 38 words
The apparatus of claim 1 including: means located along the optical axis of the light beam between the measuring cell means and means having an annular slit to reflect the transmitted light to the second light detector means.
Claim 12
Dependent Claim 27 words
The apparatus of claim 10 wherein: the means to reflect the transmitted light to the second light detector means is secured to means having the annular slit.
Claim 13
Independent Claim 281 words
An apparatus for measuring the intensity of light scattered by a test fluid comprising: means for providing a light beam, measuring cell means having a chamber accommodating test fluid, said measuring cell means including a body of non-light reflecting material having a central chamber, an inlet pathway open to one side of the chamber, and an outlet pathway open to the other side of said chamber, said chamber and inlet and outlet pathways accommodating flowing test fluid, glass block means secured to opposite sides of the body, said chamber being aligned with the optical axis of the light beam whereby the light beam passes through the test fluid in said chamber as transmitted light and scattered light, means having an annular slit located adjacent the measuring cell means aligned to match the axis of the scattered light, first light detector means operable to monitor the intensity of scattered light passing through said annular slit, second light detector means operable to monitor the intensity of the transmitted light, and electronic circuit means connected to said first and second light detector means operable to use variations of the intensity of the transmitted light to compensate for fluctuations of the intensity of the scattered light to provide an output related to the intensity of the scattered light, said circuit means having first means connected to the output of the second light detector means, reference voltage means connected to the first means, and power supply means connected to the output of the first means and the input of the first light detector means whereby variations of the scattered light are compensated by the variations of the transmitted light detected by the second light detector means.
Claim 14
Independent Claim 281 words
An apparatus for measuring the intensity of light scattered by a test fluid comprising: means for providing a light beam, measuring cell means having a chamber accommodating test fluid, said measuring cell means including a body of non-light reflecting material having a central chamber, an inlet pathway open to one side of the chamber, and an outlet pathway open to the other side of said chamber, said chamber and inlet and outlet pathways accommodating flowing test fluid, glass block means secured to opposite sides of the body, said chamber being aligned with the optical axis of the light beam whereby the light beam passes through the test fluid in said chamber as transmitted light and scattered light, means having an annular slit located adjacent the measuring cell means aligned to match the axis of the scattered light, first light detector means operable to monitor the intensity of scattered light passing through said annular slit, second light detector means operable to monitor the intensity of the transmitted light, and electronic circuit means connected to said first and second light detector means operable to use variations of the intensity of the transmitted light to compensate for fluctuations of the intensity of the scattered light to provide an output related to the intensity of the scattered light, said circuit means having first means connected to the output of the second light detector means, reference voltage means connected to the first means, and power supply means connected to the output of the first means and the input of the first light detector means whereby variations of the scattered light are compensated by the variations of the transmitted light detected by the second light detector means.
Claim 15
Dependent Claim 15 words
The apparatus of claim 12 wherein: the first light detector means comprises a photomultiplier tube.
Claim 16
Dependent Claim 32 words
The apparatus of claim 12 including: lens means between the means having an annular slit and the first light detector means for directing the scattered light to the first light detector means.
Claim 17
Dependent Claim 103 words
The apparatus of claim 12 wherein: said first means of the electronic circuit means includes first amplifier means connected to the output of the second light detector means, and second amplifier means connected to the output of the first amplifier means, said reference voltage means being connected to the second amplifier means providing the second amplifier means with a reference voltage, and said power supply means being connected to the output of the second amplifier means, said power supply means having an output related to the output of the second amplifier means and connected to the input of the first light detector means.
Claim 18
Dependent Claim 38 words
The apparatus of claim 12 including: means located along the optical axis of the light beam between the measuring cell means and means having an annular slit to reflect the transmitted light to the second light detector means.
Claim 19
Dependent Claim 27 words
The apparatus of claim 16 wherein: the means to reflect the transmitted light to the second light detector means is secured to means having the annular slit.
Claim 20
Dependent Claim 82 words
The apparatus of claim 12 wherein: said first means of the electronic circuit means includes amplifier means connected to the output of the second light detector means, said reference voltage means being connected to the amplifier means providing the amplifier means with a reference voltage, and said power supply means being connected to the amplifier means, said power supply means having an output related to the output of the amplifier means and connected to the input of the first light detector means.
Claim 21
Independent Claim 232 words
An apparatus for measuring the intensity of light scattered by a test fluid comprising: means for providing a light beam, measuring cell means having a chamber for accommodating test fluid, said chamber of the measuring cell means being aligned with the optical axis of the light beam whereby the light beam passes through the test fluid as transmitted light and scattered light, means having a slit located adjacent the measuring cell means aligned to match the axis of the scattered light, first light detector means operable to monitor the intensity of scattered light passing through said slit, second light detector means operable to monitor the intensity of the transmitted light, and electronic circuit means connected to said first and second light detector means operable to use variations of the intensity of the transmitted light to compensate for fluctuations of the intensity of the scattered light to provide an output related to the intensity of the scattered light, said electronic circuit means having amplifier means connected to the output of the second light detector means, reference voltage means connected to said amplifier means providing said amplifier means with a reference voltage, and power supply means connected to the output of said amplifier means and input of the first light detector means whereby variations of the scattered light are compensated by the variations of the transmitted light detected by the second light detector means.
Claim 22
Independent Claim 232 words
An apparatus for measuring the intensity of light scattered by a test fluid comprising: means for providing a light beam, measuring cell means having a chamber for accommodating test fluid, said chamber of the measuring cell means being aligned with the optical axis of the light beam whereby the light beam passes through the test fluid as transmitted light and scattered light, means having a slit located adjacent the measuring cell means aligned to match the axis of the scattered light, first light detector means operable to monitor the intensity of scattered light passing through said slit, second light detector means operable to monitor the intensity of the transmitted light, and electronic circuit means connected to said first and second light detector means operable to use variations of the intensity of the transmitted light to compensate for fluctuations of the intensity of the scattered light to provide an output related to the intensity of the scattered light, said electronic circuit means having amplifier means connected to the output of the second light detector means, reference voltage means connected to said amplifier means providing said amplifier means with a reference voltage, and power supply means connected to the output of said amplifier means and input of the first light detector means whereby variations of the scattered light are compensated by the variations of the transmitted light detected by the second light detector means.
Claim 23
Dependent Claim 59 words
The apparatus of claim 19 wherein: said measuring cell means includes a body of non-light reflecting material, said body having said chamber, an inlet pathway connected to the chamber for carrying test fluid to the chamber, and an outlet pathway connected to the chamber for carrying test fluid from the chamber whereby said test fluid flows through said chamber.
Claim 24
Dependent Claim 16 words
The apparatus of claim 20 including: glass block means secured to opposite sides of the body.
Claim 25
Dependent Claim 15 words
The apparatus of claim 19 wherein: the first light detector means comprises a photomultiplier tube.
Claim 26
Independent Claim 17 words
The apparatus of claims 19 or 22 wherein: the second light detector means comprises a photomultiplier tube.
Claim 27
Dependent Claim 31 words
The apparatus of claim 19 including: lens means between the means having a slit and the first light detector means for directing the scattered light to the first light detector means.
Claim 28
Dependent Claim 37 words
The apparatus of claim 19 including: means located along the optical axis of the light beam between the measuring cell means and means having a slit to reflect the transmitted light to the second light detector means.
Claim 29
Dependent Claim 26 words
The apparatus of claim 25 wherein: the means to reflect the transmitted light to the second light detector means is secured to means having the slit.

References Cited (Backward Citations)

US3518437A Cited
US3936192A Cited
US3843268A Cited
US4146799A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-12-12 1987-06-13 1987-12-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-12-12 1991-06-13 1991-12-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-12-12 1995-06-13 1995-12-13 $7700.00 Window Closed / Lapsed

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