Patent ID: 9664538
Date: 2017-05-30
CPC Classifications: G01D,G09B

Claim:
1. A rotational sensor to sense an angle of an object, comprising: a) a plurality of first emitting sources, to either emit onto, or from said object: b) a plurality of first receiving sensors, to each receive emissions from a corresponding one of said plurality of first emitting sources, either directly or indirectly, said emissions received dependent on said angle, each of said first receiving sensors outputting a first signal, proportionate to said emissions, as a course measurement of said angle, wherein said plurality of first emitting sources and said plurality of first receiving sensors are arranged in a substantially circular array, through which said object can pass: c) at least one second emitting source, to emit onto, or from said object, d) at least one second receiving sensor, to receive emissions from said at least one second emitting source, either directly or indirectly, said emissions received dependent on said angle, said at least one second receiving sensor outputting a second signal, proportionate to said emissions from said at least one second emitting source, as a fine measurement of said angle, wherein said first signal and said second signal are capable of being combined to determine said angle; wherein said first emitting source illuminates at least part of a surface of said object and said first receiving source receives said illumination as a reflection from said surface.