Optical angular position sensing system for use with a galvanome

Details Optical angular position sensing system for use with a galvanome Optical angular position sensing system for use with a galvanome

1992-03-06

1993-06-29

Nelms, David C.

Radiant energy

Photocells; circuits and apparatus

Optical or pre-photocell system

250205, G01D 530, G01J 132

Patent

active

052237109

ABSTRACT:
An optical angular position sensing system determines the angular position of a primary, beam-directing mirror by sensing the position of a beam from a secondary light source reflected from a secondary mirror on the back surface of the primary mirror. The position sensing system includes a photodetector that produces two output currents, the difference of which represents both the position of the reflected secondary beam and the intensity of the light source. A second servo-loop dynamically normalizes the output of the sensor by controlling the intensity of the light source to stabilize the total output of the sensor. The light source is oriented relative to the secondary mirror such that the mirror reflects a long dimension of a cross-section of the beam in a direction which is perpendicular to the direction of beam movement. The beam thus overlaps the transverse dimension of the photodetector so that maintenance of a predetermined light flux on the photodetector does not require precise placement of the light source or the sensor. To provide a low mass mirror, the primary mirror is formed on a silicon substrate and the secondary mirror is formed by adding a reflective coating to the back surface of the substrate. Forming the mirrors on two surfaces of the substrate also eliminates position errors related to differences in the relative positions of the two mirrors.

REFERENCES:
patent: 4024545 (1977-05-01), Dowling et al.
patent: 4152588 (1979-05-01), Klatt et al.
patent: 4544241 (1985-10-01), LaBudde et al.
patent: 4621351 (1986-11-01), Baer et al.
patent: 4630276 (1986-12-01), Moran
patent: 4687920 (1987-08-01), van der Linden
patent: 4714339 (1987-12-01), Lau et al.
patent: 4721860 (1988-01-01), Troendle
patent: 4792931 (1988-12-01), Nishida et al.
patent: 4797868 (1989-01-01), Ando
patent: 4813032 (1989-05-01), Koyama
patent: 4840483 (1989-06-01), Haffner
patent: 4926403 (1990-05-01), Tsuyuguchi et al.
patent: 4972344 (1990-11-01), Stoddard et al.
patent: 4987293 (1991-01-01), Baciak
patent: 5107365 (1992-04-01), Ota
patent: 5136159 (1992-08-01), Nakazawa et al.
J. Torkel Wallmark, "A New Semiconductor Photocell Using Lateral Photoeffect", Proc. IRE, pp. 474-483, Oct. 1956.
G. P. Petersson and L. Lindholm, "Position Sensitive Light Detectors with High Linearity", IEEE Journal of Solid-State Circuits, vol. SC13, No. 3, pp. 392-399, Jun. 1978.
W. R. Gonnason, J. W. Haslett, and F. N., Trofimenkoff, "A Low Cost High Resolution Optical Position Sensor", IEEE Transactions on Instrumentation and Measurement, vol. 39, No. 4, pp. 653-663, Aug. 1990.

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