Radiant energy – Photocells; circuits and apparatus – Optical or pre-photocell system
Patent
1986-02-07
1987-03-24
Nelms, David C.
Radiant energy
Photocells; circuits and apparatus
Optical or pre-photocell system
356351, 73657, H01J 516
Patent
active
046527443
ABSTRACT:
A light source (10) coupled to a first fiber optic waveguide (14) which is coupled by a first directional coupler (22) and a second directional coupler (24) to a second waveguide (20). The first waveguide (14) has a phase modulator (60), a delay loop (62) and a polarization controller (68) therein to cause a differential delay time T on counterpropagating coherent light waves phase modulated at a frequency 1.sub.M. The first directional coupler (22) has one part connected to a photodetector (28) and the second directional coupler (24) has a probe (20D) coupled to the first fiber (14) and the second fiber (20). The probe directs light toward a surface (18) whereupon the counterpropagating waves are shifted in phase by an amount proportional to the amplitude of displacement of the surface 18.
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Bowers John E.
Kino Gordon S.
Nelms David C.
Oen William L.
The Board of Trustees of the Leland Stanford Junior University
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