US3876875A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical system for forming an image of an object in a given plane
Assignee: US Philips Corp
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Filing: 1973-03-28
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Granted: 1975-04-08
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Expires: 1993-03-28
Abstract
Abstract A system for forming an image of an object in an image plane is described. By disposing a reflecting diaphragm in the back focal plane of an objective lens system, the curvature of this diaphragm being adjustable by means of a control element to which an electric signal supplied by an image detection system is applied, the size of the image in the image plane can be rendered independent of a change in the distances from the object to the optical system and from this system to the image plane.
Inventors
- 👤 Christiaan Hendrik Fran Velzel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:12
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/08; G11B7/09; G11B7/0908; G02; G02B; G02B27/00; G02B27/40
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
119 words
Optical system for forming an image of an illuminated object in an image plane, the size of the image in this image plane being independent of a variation in the distances from the object to the optical system and from the optical system to the image plane, with the use of an electrical distance detection system signal indicating said variations in distance, comprising an objective lens system for focussing the image of the object in the image plane; a reflecting diaphragm is disposed in the back focal plane of the objective lens system, and a detection signal responsive control element means for adjusting the curvature of the diaphragm in response to the electric signal from the distance detection system.
Claim 2
Dependent Claim
119 words
Optical system for forming an image of an illuminated object in an image plane, the size of the image in this image plane being independent of a variation in the distances from the object to the optical system and from the optical system to the image plane, with the use of an electrical distance detection system signal indicating said variations in distance, comprising an objective lens system for focussing the image of the object in the image plane; a reflecting diaphragm is disposed in the back focal plane of the objective lens system, and a detection signal responsive control element means for adjusting the curvature of the diaphragm in response to the electric signal from the distance detection system.
Claim 3
Dependent Claim
38 words
Optical system as claimed in claim 1, further comprising an additional lens arranged between the objective lens system and the diaphragm for forming an image of the back focal plane of the objective lens system on the diaphragm.
Claim 4
Dependent Claim
37 words
Optical system as claimed in claim 1 wherein the control element is a piezoelectric element which comprises a plurality of plates of a piezoelectric material which are clamped along two edges and carry electrodes on both surfaces.
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) | 1978-04-07 | 1978-10-07 | 1979-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-07 | 1982-10-07 | 1983-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-07 | 1986-10-07 | 1987-04-08 | $7700.00 | Window Closed / Lapsed |