US Patent 11681066 Detector locator system

A proximity sensor comprising: a loop comprising an outer surface and an inner surface, at least a portion of the inner surface being a reflective surface; a light emitter positioned to emit light onto the reflective surface; a light detector positioned to preferentially receive light emitted from the light emitter and reflected from the reflective surface; and a processor that is configured, responsive to a set of instructions stored in a memory, to determine a degree of proximity of an object to the inner surface of the loop responsive to a reduction in an intensity of light emitted from the light emitter that is received by the light detector.