Patent US3564263A successfully refreshed from Google Patents.
US3564263A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical particle sensor having a light collector mounted on the photosensor
Assignee: Coulter Electronics Inc
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Filing: 1968-09-30
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Granted: 1971-02-16
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Expires: 1988-09-30
Abstract
Abstract A black specular surfaced tube has an open end aligned with the illuminating beam of an optical particle sensor. The manner in which the black specular surfaced tube is associated with the other elements of the particle sensor permits the tube to act essentially as a black hole for conducting the unscattered light from the illuminating beam out of the particle sensor.
Inventors
- 👤 Clyde C Shaw
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:25
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/47; G01N21/49; G01N21/53
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
193 words
For use in an optical particle sensor for determining the particle size and number concentration of particles suspended in a flow stream by measuring the scattering of a focused light beam projected through the flow stream, said sensor comprising, measuring means for measuring scattered light received at the measuring means, flow means for directing a stream of suspended particles in front of the measuring means, and illuminating means for focusing an illuminating beam of light on a critical volume of the stream; the improvement which comprises, a specular surfaced tube located between the stream and the measuring means and having an open end aligned with the illuminating beam and positioned to receive and contain all of the light from the focused illuminating beam that passes through the stream of suspended particles without being scattered or absorbed by the particles, and a scattered light collecting member mounted on the receiving surface of the measuring means with the axis of the collecting member coincident with the axis of the focused illuminating beam and wherein said member holds said open end of the specular surfaced tube in the aligned position with respect to the illuminating beam.
Claim 2
Dependent Claim
193 words
For use in an optical particle sensor for determining the particle size and number concentration of particles suspended in a flow stream by measuring the scattering of a focused light beam projected through the flow stream, said sensor comprising, measuring means for measuring scattered light received at the measuring means, flow means for directing a stream of suspended particles in front of the measuring means, and illuminating means for focusing an illuminating beam of light on a critical volume of the stream; the improvement which comprises, a specular surfaced tube located between the stream and the measuring means and having an open end aligned with the illuminating beam and positioned to receive and contain all of the light from the focused illuminating beam that passes through the stream of suspended particles without being scattered or absorbed by the particles, and a scattered light collecting member mounted on the receiving surface of the measuring means with the axis of the collecting member coincident with the axis of the focused illuminating beam and wherein said member holds said open end of the specular surfaced tube in the aligned position with respect to the illuminating beam.
Claim 3
Dependent Claim
66 words
A particle sensor as defined in claim 1 wherein the measuring means include a photomultiplier tube having a tube surface positioned to receive the scattered light and wherein the specular surfaced tube is a black tube which conducts the unscattered illuminating beam away from said surface of the photomultiplier tube while absorbing the beam as the beam is conducted specularly down the interior of the tube.
Claim 4
Dependent Claim
87 words
A particle sensor as defiNed in claim 1 wherein said collecting member is a plastic member which is bonded to said surface of the measuring means to form a sealed interface which minimizes reflection losses and wherein the end of the plastic member adjacent the critical volume is a concave surface having a radius of curvature located at the center of said critical volume so that all scattered light strikes the concave surface in a direction normal to the surface to minimize reflection losses at the surface.
Claim 5
Dependent Claim
32 words
A particle sensor as defined in claim 3 wherein the collecting member is cone-shaped and has a lateral surface covered with a reflective coating to prevent light losses through the lateral surface.
Claim 6
Dependent Claim
114 words
An optical particle sensor for determining the particle size and concentration of particles suspended in a flow stream by measuring the scattering of a focused light beam projected through the flow stream, said particle sensor comprising, measuring means for measuring scattered light including a photomultiplier tube having a tube surface positioned to receive the scattered light, flow means for directing a stream of suspended particles in front of the tube surface, illuminating means for focusing an illuminating beam of light on a critical volume of the stream, and a light collecting conical member mounted on the tube surface with the axis of the conical member coincident with the axis of the focused illuminating beam.
Claim 7
Dependent Claim
114 words
An optical particle sensor for determining the particle size and concentration of particles suspended in a flow stream by measuring the scattering of a focused light beam projected through the flow stream, said particle sensor comprising, measuring means for measuring scattered light including a photomultiplier tube having a tube surface positioned to receive the scattered light, flow means for directing a stream of suspended particles in front of the tube surface, illuminating means for focusing an illuminating beam of light on a critical volume of the stream, and a light collecting conical member mounted on the tube surface with the axis of the conical member coincident with the axis of the focused illuminating beam.
Claim 8
Dependent Claim
32 words
A particle sensor as defined in claim 5 wherein the light collecting conical member is a plastic member bonded to said tube surface to form a sealed interface which minimizes reflection losses.
Claim 9
Dependent Claim
59 words
A particle sensor as defined in claim 6 wherein the end of the conical member adjacent the critical volume is a concave surface having a radius of curvature located at the center of the critical volume so that all scattered light strikes the concave surface in a directional normal to the surface to minimize reflection losses at the surface.
Claim 10
Dependent Claim
30 words
A particle sensor as defined in claim 5, wherein the lateral surface of the conical member is covered with a reflective coating to prevent light losses through the lateral surface.
Claim 11
Dependent Claim
29 words
A particle sensor defined as in claim 1 wherein said light collecting member is frustum-shaped and has its major base mounted to said receiving surface of the measuring means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-02-15 | 1974-08-17 | 1975-02-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-15 | 1978-08-17 | 1979-02-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-15 | 1982-08-17 | 1983-02-16 | $7700.00 | Window Closed / Lapsed |