Optical microphone using Fabry-Perot interferometer and fibre=optics feed line

摘要

The optical microphone has a light source e.g. a superluminescent diode or an ordinary LED, an optical fibre lead (1) and a Fabry-Perot interferometer, including a pair of relatively spaced reflectors (4,6). The first reflector (4) is provided by the end face of the optical fibre lead, the second reflector (6) provided by the end face of an optical fibre section (8) coupled to a separate membrane (11), for deflection in response to the air pressure variations.