Manner and device null for measuring which uses the acousto-Optics acoustooptics device

摘要

Optical measuring apparatus includes a phase sensitive measuring device (8, 9, 14, 16) including an acousto-optic device adapted to modulate a parameter of a light beam (1), beam splitter means (5) to split said light beam into a reference beam (6) and a probe beam (7), detector means (8, 13) respectively to detect said reference beam and said probe beam after interrogation of an element under test, and measuring means (9, 14, 15) to measure the differential of an optical property of the element measured by said probe beam.