Patent US3876311A successfully refreshed from Google Patents.
US3876311A
Expired / Lapsed
US
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Two-axis photoelectric detector device
Assignee: Nikon Corp
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Filing: 1974-04-30
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Granted: 1975-04-08
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Expires: 1994-04-30
Abstract
Abstract A two-axis photoelectric detector device for detecting the position of a body with respect to two directions comprises a plate having a reticle slit disposed at a position conjugate with a reticle mark of the body with respect to an objective lens, two scanning means orthogonally disposed forwardly of the slit for oscillating a light beam and the two slit portions of the reticle slit relatively to each other, a photoelectric converter for receiving the light passed through the slit, and two synchronous rectifier circuits for receiving electrical signals from the photoelectric converter. A signal is applied from an oscillator to one of the synchronous rectifier circuits and one of the scanning means. A signal 90.degree. out of phase with the signal from the oscillator is applied to the other synchronous rectifier circuit and the other scanning means. The outputs of the two synchronous rectifier circuits are delivered to two indicating meters, respectively.
Inventors
- 👤 Shinya Sasayama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 18:35
CPC Classifications
G; G02; G02B; G02B21/00; G02B21/06; G02B21/08; G01; G01D; G01D5/00; G01D5/26
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
290 words
A two-axis photoelectric detector device for detecting the position of a body with respect to two directional axes, comprising: i. mark means consisting of two linear marks formed on said body and extending in two directions; ii. an imageforming lens system for forming the image of said mark means; iii. a slit plate having two slit portions disposed at locations conjugate with said marks with respect to said image-forming lens system and extending in two directions corresponding to said marks; iv. first scanning means for causing an image-forming light beam for one of said linear marks passed through said lens system and one of said slit portions corresponding to said one linear mark to be relatively scanned at a predetermined frequency and in a direction perpendicular to the lengthwise direction of said one linear mark and said one slit portion; v. second scanning means for causing an image-forming light beam for the other linear mark and the other slit portion corresponding to said other linear mark to be relatively scanned at said predetermined frequency and in a direction perpendicular to the lengthwise direction of said other linear mark and said other slit portion but with a phase delay of 90.degree. relative to said first scanning means; vi. photoelectric converter means for converting into electrical signals the light passed through said slit portions of said slit plate; and vii. synchronous rectifier means for separating the output signals from said photoelectric converter means into a signal in phase with the scanning of said first scanning means and of the same frequency as the frequency of said first scanning and a signal in phase with the scanning of said second means and of the same frequency as the frequency of said latter scanning.
Claim 2
Dependent Claim
290 words
A two-axis photoelectric detector device for detecting the position of a body with respect to two directional axes, comprising: i. mark means consisting of two linear marks formed on said body and extending in two directions; ii. an imageforming lens system for forming the image of said mark means; iii. a slit plate having two slit portions disposed at locations conjugate with said marks with respect to said image-forming lens system and extending in two directions corresponding to said marks; iv. first scanning means for causing an image-forming light beam for one of said linear marks passed through said lens system and one of said slit portions corresponding to said one linear mark to be relatively scanned at a predetermined frequency and in a direction perpendicular to the lengthwise direction of said one linear mark and said one slit portion; v. second scanning means for causing an image-forming light beam for the other linear mark and the other slit portion corresponding to said other linear mark to be relatively scanned at said predetermined frequency and in a direction perpendicular to the lengthwise direction of said other linear mark and said other slit portion but with a phase delay of 90.degree. relative to said first scanning means; vi. photoelectric converter means for converting into electrical signals the light passed through said slit portions of said slit plate; and vii. synchronous rectifier means for separating the output signals from said photoelectric converter means into a signal in phase with the scanning of said first scanning means and of the same frequency as the frequency of said first scanning and a signal in phase with the scanning of said second means and of the same frequency as the frequency of said latter scanning.
Claim 3
Dependent Claim
27 words
A two-axis photoelectric detector device according the claim 1, wherein said two linear marks extend in orthogonal directions and said two slit portions extend in orthogonal directions.
Claim 4
Dependent Claim
25 words
A two-axis photoelectric detector device according the claim 1, further comprising two indicator members receiving as input the two signals from said synchronous rectifier means.
References Cited (Backward Citations)
US3739247A
Cited
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 |