US3901588A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Calibrating device for light scatter photometering instrument
Assignee: Warner Lambert Co LLC
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Filing: 1973-06-19
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Granted: 1975-08-26
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Expires: 1993-06-19
Abstract
Abstract A flat sandwich composite plate of nested wedge-shaped sheets of highly transparent and gray neutral density filter glasses is enclosed in a frame. A bracket on the frame mounts it on the carriage of an optical instrument which measures the light scattering characteristics of a series of samples traversed on a carriage past a photometering station. A surface of the composite plate has a mat finish which scatters the light passing through it. The density and thickness of the filter glass are arranged to cover a predetermined range of light scatter corresponding to that caused by the range of samples which the optical instrument can accurately measure. An appended flat section of filter glass provides light scatter characteristics corresponding to an auxiliary sample characteristic. The transmittance of the appended section is adjusted by a movable leaf and notched adjusting segments. The mat surface is obtained by frosting a surface of the filter glass by blasting or grinding with No. 9 micron grit. The neutral density filter glass has a flat spectrum characteristic obtained by doping with carbon.
Inventors
- 👤 David K Longhenry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:09
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/47; G01N21/4785
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
270 words
A device for calibrating an optical instrument which measures the light scattering characteristics of a series of samples traversed on a carriage in steps past a photometering station comprising an elongated frame, a bracket attached to the frame for readily detachably mounting said frame upon said carriage in a predetermined position, an elongated composite plate of transparent glass in said frame, said composite plate comprising a flat sandwich of nested wedge-shaped sheets of highly transparent and neutral density filter glasses, a surface of said composite plate having a uniform mat finish which scatters the light passing through it, and the density of the filter glass being sufficient to cover a predetermined range of light scatter corresponding to that caused by a predetermined range of said samples throughout the varying thickness of said filter glass over the length of said composite plate as said device is traversed in steps past the photometering station, a flat neutral filter glass section is appended alongside the length of said wedge-shaped sheet of neutral density filter glass, said flat neutral filter glass section has a surface having a mat finish for an auxiliary light scattering verification, a variable leaf is disposed over said appended section, movable means attaching said leaf to said frame whereby the position of said variable leaf can be modified for adjusting the amount of scattered light transmitting through said flat appended section, fine adjusting means is provided on said leaf and said frame for precisely adjusting the position of said leaf over said appended glass section, and said fine adjusting means comprises overlying notched sections on said leaf and said frame.
Claim 2
Independent Claim
270 words
A device for calibrating an optical instrument which measures the light scattering characteristics of a series of samples traversed on a carriage in steps past a photometering station comprising an elongated frame, a bracket attached to the frame for readily detachably mounting said frame upon said carriage in a predetermined position, an elongated composite plate of transparent glass in said frame, said composite plate comprising a flat sandwich of nested wedge-shaped sheets of highly transparent and neutral density filter glasses, a surface of said composite plate having a uniform mat finish which scatters the light passing through it, and the density of the filter glass being sufficient to cover a predetermined range of light scatter corresponding to that caused by a predetermined range of said samples throughout the varying thickness of said filter glass over the length of said composite plate as said device is traversed in steps past the photometering station, a flat neutral filter glass section is appended alongside the length of said wedge-shaped sheet of neutral density filter glass, said flat neutral filter glass section has a surface having a mat finish for an auxiliary light scattering verification, a variable leaf is disposed over said appended section, movable means attaching said leaf to said frame whereby the position of said variable leaf can be modified for adjusting the amount of scattered light transmitting through said flat appended section, fine adjusting means is provided on said leaf and said frame for precisely adjusting the position of said leaf over said appended glass section, and said fine adjusting means comprises overlying notched sections on said leaf and said frame.
Claim 3
Dependent Claim
16 words
A device as set forth in claim 1 wherein said mat finish comprises a frosted surface.
Claim 4
Dependent Claim
23 words
A device as set forth in claim 2 wherein said frosted surface has irregularities and said irregularities are about a 9 micron size.
Claim 5
Dependent Claim
26 words
A device as set forth in claim 1 wherein said wedge-shaped sheets have substantially blunt thin edges from about 0.060 inch to about 0.010 inch thick.
Claim 6
Dependent Claim
16 words
A device as set forth in claim 1 wherein said overlying notched sections comprise arcuate sections.
Claim 7
Dependent Claim
25 words
A device as set forth in claim 1 wherein said neutral density filter glass is a gray flat spectrum neutral density filter glass incorporating carbon.
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) | 1978-08-25 | 1979-02-24 | 1979-08-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-25 | 1983-02-24 | 1983-08-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-25 | 1987-02-24 | 1987-08-26 | $7700.00 | Window Closed / Lapsed |