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US4577101A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Shaft encoder with an optical system comprising two straight-line-generatrix surfaces
Assignee: US Philips Corp
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Filing: 1983-06-08
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Granted: 1986-03-18
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Expires: 2003-06-08
Abstract
Abstract An optical measuring system for determining angular displacements of an object, including a radial grating connected to the object. Optical elements including two straight-line-generatrix surfaces focus the grating image as a parallel grating image onto a linear array radiation-sensitive detection system. The linear array may be photodiodes functioning as a grating-like element.
Inventors
- 👤 Joannes G. Bremer
- 👤 Klaas Compaan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 08:34
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/02; H03H9/125; H03H9/145; G; G01; G01D; G01D5/00; G01D5/26; G01D5/32; G01D5/34; G01D5/347; G01D5/34707; G01D5/34715; G01D5/3473
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
68 words
An apparatus for determining the angular displacement of an object, comprising a measurement grating, means for mechanically connecting said grating to the object, and a radiation-sensitive detection system comprising a grating-like element, characterized in thatthe measurement grating comprises radially extending grating strips on a circular disk, and the apparatus includes an optical system comprising two straight-line-generatrix surfaces is arranged between the measurement grating and the radiation-sensitive detection system.
Claim 2
Independent Claim
68 words
An apparatus for determining the angular displacement of an object, comprising a measurement grating, means for mechanically connecting said grating to the object, and a radiation-sensitive detection system comprising a grating-like element, characterized in thatthe measurement grating comprises radially extending grating strips on a circular disk, and the apparatus includes an optical system comprising two straight-line-generatrix surfaces is arranged between the measurement grating and the radiation-sensitive detection system.
Claim 3
Dependent Claim
22 words
An apparatus as claimed in claim 1, characterized in that the two straight-line-generatrix surfaces comprise a radiation-refracting surface and a radiation-reflecting surface.
Claim 4
Dependent Claim
25 words
An apparatus as claimed in claim 2, characterized in that the radiation-refracting surface is a cylindrical lens and the radiation-reflecting surface is a conical reflector.
Claim 5
Dependent Claim
19 words
An apparatus as claimed in claim 1, characterized in that the two straight-line-generatrix surfaces are constituted, by radiation-reflecting surfaces.
Claim 6
Dependent Claim
27 words
An apparatus as claimed in claim 4, characterized in that one of the straight-line-generatrix surfaces is a cylindrical mirror and the other surface straight-line-generatrix a conical reflector.
Claim 7
Dependent Claim
55 words
An apparatus as claimed in claim 5, characterized in that the radiation-sensitive detection system comprises a multiple photo-cell formed by an array of line-shaped photo-diodes which are sequentially connected to an electronic circuit via an electrical switch, and said electronic circuit processes the signal generated by the photo-diodes so that a travelling grating is simulated.
Claim 8
Dependent Claim
18 words
An apparatus as claimed in claim 6, characterized in that the two straight-line-generatrix surfaces form one constructional unit.
Claim 9
Dependent Claim
55 words
An apparatus as claimed in claim 4, characterized in that the radiation-sensitive detection system comprises a multiple photo-cell formed by an array of line-shaped photo-diodes which are sequentially connected to an electronic circuit via an electrical switch, and said electronic circuit processes the signal generated by the photo-diodes so that a travelling grating is simulated.
Claim 10
Dependent Claim
18 words
An apparatus as claimed in claim 8, characterized in that the two straight-line-generatrix surfaces form one constructional unit.
Claim 11
Dependent Claim
55 words
An apparatus as claimed in claim 3, characterized in that the radiation-sensitive detection system comprises a multiple photo-cell formed by an array of line-shaped photo-diodes which are sequentially connected to an electronic circuit via an electrical switch, and said electronic circuit processes the signal generated by the photo-diodes so that a travelling grating is simulated.
Claim 12
Dependent Claim
18 words
An apparatus as claimed in claim 10, characterized in that the two straight-line-generatrix surfaces form one constructional unit.
Claim 13
Dependent Claim
55 words
An apparatus as claimed in claim 2, characterized in that the radiation-sensitive detection system comprises a multiple photo-cell formed by an array of line-shaped photo-diodes which are sequentially connected to an electronic circuit via an electrical switch, and said electronic circuit processes the signal generated by the photo-diodes so that a travelling grating is simulated.
Claim 14
Dependent Claim
18 words
An apparatus as claimed in claim 12, characterized in that the two straight-line-generatrix surfaces form one constructional unit.
Claim 15
Dependent Claim
55 words
An apparatus as claimed in claim 1, characterized in that the radiation-sensitive detection system comprises a multiple photo-cell formed by an array of line-shaped photo-diodes which are sequentially connected to an electronic circuit via an electrical switch, and said electronic circuit processes the signal generated by the photo-diodes so that a travelling grating is simulated.
Claim 16
Dependent Claim
18 words
An apparatus as claimed in claim 14, characterized in that the two straight-line-generatrix surfaces form one constructional unit.
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) | 1989-03-17 | 1989-09-16 | 1990-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-03-17 | 1993-09-16 | 1994-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-03-17 | 1997-09-16 | 1998-03-18 | $7700.00 | Window Closed / Lapsed |