Interferometer system and method for controlling the activation of a regulating interferometer in response to an output signal

摘要

PCT No. PCT/DE93/00843 Sec. 371 Date Apr. 24, 1995 Sec. 102(e) Date Apr. 24, 1995 PCT Filed Sep. 13, 1993 PCT Pub. No. WO94/07109 PCT Pub. Date Mar. 31, 1994A laser interferometer having a laser to produce a beam of light and a first beam splitter to split the beam of light into first and second portions. The first portion is directed towards a measuring interferometer and the second portion is directed toward a first regulating interferometer having a regulating section. A beam director for directing a portion of the second portion of the beam of light toward a second regulating interferometer having a regulating section. A switch connected to the second regulating interferometer which turns the second regulating interferometer on when a first output signal is less than a first predetermined maximum signal threshold value or exceeds a first predetermined minimum signal threshold value and if the second regulating interferometer has the next largest regulating section length relative to the length of the regulating section of the first regulating interferometer. The switch also turns the second regulating interferometer on when the first output signal exceeds a second predetermined maximum signal threshold value or is less than a second predetermined minimum signal threshold value and if the second regulating interferometer has the next smallest regulating section length relative to the length of the regulating section of the first regulating interferometer. A control device for controlling the wavelength of the beam of light in response to the output control signal corresponding to the regulating interferometer switched on at that given time.