Patent US3594087A successfully refreshed from Google Patents.
US3594087A
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US
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Optical densitometer with retroreflective means
Assignee: Baxter International Inc
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Filing: 1969-11-06
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Granted: 1971-07-20
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Expires: 1989-11-06
Abstract
Abstract An improved optical densitometer is provided for measuring the varying optical densities of a photographic film, or equivalent media, along the length of the media, and which includes retroreflective means for compensating for irregularities in the surface of the media which would otherwise affect the precision of the optical density readings.
Inventors
- 👤 Victor Eduardo Vasquez Miranda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:12
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/59; G01N21/5907
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
157 words
Optical densitometer apparatus including: a transparent carrier for supporting media to undergo densitometer measurements; a light source positioned to direct light through said media and through said carrier; means positioned in the optical path between said light source and said media for forming light from said source into a beam directed through said media and carrier; means positioned on the opposite side of said carrier for redirecting the light passing therethrough back through said carrier and through said media, said redirecting means being composed of a retroreflective material capable of reflecting rays of said light beam incident thereon directly back along the paths of incidence thereof; a photoelectric transducer; and a partially reflective member positioned in said optical path between said light source and said media for passing the light beam from said light source to said media and for reflecting the light beam redirected through said media from said retroreflective redirecting means onto said photoelectric transducer.
Claim 2
Dependent Claim
157 words
Optical densitometer apparatus including: a transparent carrier for supporting media to undergo densitometer measurements; a light source positioned to direct light through said media and through said carrier; means positioned in the optical path between said light source and said media for forming light from said source into a beam directed through said media and carrier; means positioned on the opposite side of said carrier for redirecting the light passing therethrough back through said carrier and through said media, said redirecting means being composed of a retroreflective material capable of reflecting rays of said light beam incident thereon directly back along the paths of incidence thereof; a photoelectric transducer; and a partially reflective member positioned in said optical path between said light source and said media for passing the light beam from said light source to said media and for reflecting the light beam redirected through said media from said retroreflective redirecting means onto said photoelectric transducer.
Claim 3
Dependent Claim
20 words
The apparatus defined in claim 1, and which includes means for providing relative movement between said beam and said media.
Claim 4
Dependent Claim
38 words
The apparatus defined in claim 1, in which said carrier and said media are tilted with respect to said beam so that surface reflections from said media are directed away from the optical path to said photoelectric transducer.
Claim 5
Dependent Claim
36 words
The test apparatus defined in claim 1, and which includes a scanning element positioned in the optical path between said source and said media, for scanning the beam incident on said media across the surface thereof.
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) | 1974-07-19 | 1975-01-18 | 1975-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-19 | 1979-01-18 | 1979-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-19 | 1983-01-18 | 1983-07-20 | $7700.00 | Window Closed / Lapsed |