The opto-electrical spectral analyser uses a parallel beam system incorporating Falry-Perot interferometers (7, 25), adjacent to the pressure variation system (12). One system is illuminated by a light source (1) under investigation, whilst the other is illuminated by a laser beam source (18). Interference patterns are developed in the planes of diaphragms (13, 30) in corresponding locations. The first beam from the light source passes through an opto-electrical device (15) to a recorder (16). The laser beam passes through a double-prism light beams splitting it into 90 deg. phase shifted components, which are subsequently brought together into a backwards counter (37).
展开▼
