A simple optical displacement sensor utilizing dual-channel angle-limited integrated scattering measurements

摘要

A dual-channel optical displacement sensor based on the reflective intensity modulation is constructed. The sensor collects light scattered from the surface of a sample at a limited solid angle. This value of the angle-limited integrated scattering (ALIS) depends on the proximity between the sensor and the sample. The ALIS signals from both channels are used to check alignment of samples. The sensor is capable of measuring displacement with an accuracy about 0.5% over proximity ranging from 70 to 90 mm.