Patent US3591297A successfully refreshed from Google Patents.
US3591297A
Expired / Lapsed
US
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Photometric instrument
Assignee: Individual
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Filing: 1968-11-06
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Granted: 1971-07-06
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Expires: 1988-11-06
Abstract
Abstract A photometric instrument having two photoelectric cells coupled to a common moving coil meter, one of said cells being arranged within a casing to measure, in conjunction with an optical viewing system, a small viewing angle, and the other of said cells being adapted to be used externally of said casing to measure illumination and eventual luminance within a large viewing angle. The pointer of said coil meter is common to two reading scales one of which can be viewed through the optical view system and the other of which can be viewed from a position external of said casing.
Inventors
- 👤 Bo Anders Vilhelm Hagner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:52
CPC Classifications
G; G01; G01J; G01J1/00; G01J1/02; G01J1/04; G01J1/0407; G01J1/0411; G01J1/0437; G01J1/0233; G01J1/0247; G01J1/0271
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
216 words
A photometric instrument comprising, in combination, a casing; an optical viewing system arranged within said casing for viewing an external scene; a first photoelectric cell for sensing illumination of said external scene within a small viewing angle coupled to said optical system; a second phOtoelectric cell remotely positionable by lead means outside of said casing for sensing illumination of a scene within a large viewing angle independently of said viewing system; a meter within said casing and having a pointer, said meter being selectively coupled alternatively by switch means to said first photoelectric cell and said lead means for alternatively receiving signals from said first photoelectric cell and said second photoelectric cell; an opaque scale plate formed with an arcuate transparent portion operatively associated with said meter, said scale plate having a first reading scale arranged on said transparent portion for registering signals from said first photoelectric cell and a second reading scale viewable externally of said casing arranged on an opaque portion of said scale plate for registering signals from said second photoelectric cell, said pointer being common to both of said reading scales; and means including an angled mirror within said casing and offset from said optical viewing system for viewing said first reading scale internally via an eyepiece associated with said viewing system.
Claim 2
Dependent Claim
216 words
A photometric instrument comprising, in combination, a casing; an optical viewing system arranged within said casing for viewing an external scene; a first photoelectric cell for sensing illumination of said external scene within a small viewing angle coupled to said optical system; a second phOtoelectric cell remotely positionable by lead means outside of said casing for sensing illumination of a scene within a large viewing angle independently of said viewing system; a meter within said casing and having a pointer, said meter being selectively coupled alternatively by switch means to said first photoelectric cell and said lead means for alternatively receiving signals from said first photoelectric cell and said second photoelectric cell; an opaque scale plate formed with an arcuate transparent portion operatively associated with said meter, said scale plate having a first reading scale arranged on said transparent portion for registering signals from said first photoelectric cell and a second reading scale viewable externally of said casing arranged on an opaque portion of said scale plate for registering signals from said second photoelectric cell, said pointer being common to both of said reading scales; and means including an angled mirror within said casing and offset from said optical viewing system for viewing said first reading scale internally via an eyepiece associated with said viewing system.
Claim 3
Dependent Claim
29 words
An instrument as claimed in claim 1 in which an image plane of said optical viewing system is provided with a scale means for use in measuring solid angles.
Claim 4
Dependent Claim
15 words
An instrument as claimed in claim 1, wherein said meter is a moving coil meter.
Claim 5
Dependent Claim
19 words
An instrument as claimed in claim 1, including means for removably storing said second photoelectric cell within said casing.
References Cited (Backward Citations)
US2013363A
Cited
US2145147A
Cited
US3087379A
Cited
US3074312A
Cited
US2994257A
Cited
US3212394A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-07-05 | 1975-01-04 | 1975-07-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-05 | 1979-01-04 | 1979-07-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-05 | 1983-01-04 | 1983-07-06 | $7700.00 | Window Closed / Lapsed |