Patent ID: 7559258

Claim:
A non-contact rotary optical displacement sensor apparatus for use in conjunction with a torque transmitting mechanism, the non-contact rotary optical displacement sensor comprising: a flexure with input and output ends; a pattern of spaced reflective and non-reflective lines on at least one of the flexure and an input coupler and an output coupler attached to the flexure; a light source for generating light to at least one of the flexures and the input coupler and the output coupler; a field mask including a pattern of equally spaced opaque and transparent lines disposed at the same spacing as the pattern of reflective and non-reflective lines, the pattern of opaque and transparent lines adapted to receive the light from the light source transmitted through the field mask that is reflected by the reflective and non-reflective line patterns to create an input end output light signal and an output end output light signal; a detector receiving the input end and the output end output light signals; means, responsive to the detector, for generating for each of the input and output ends of the flexure an input and an output triangular waveform, with the amplitude difference between the input waveform and the output waveform at a sample point on both waveforms being proportional to the amount of torque; an analog to digital converter digitizing the input end and the output end output light signals received by the detector into digitized signals at a plurality of sample points during each cycle of each input and output waveforms; and a signal processor acting on the digitized signals to produce torque related measurements based on amplitude differences between sampled points on the input and output waveforms.