ABSOLUTE DISTANCE LASER INTERFEROMETER

摘要

A device for absolute distance measurement includes a first tunable light source for emitting a first wavelength light of a first tunable frequency modulated by a first modulating frequency and a second light source for emitting a second wavelength light of a second frequency modulated by a second modulating frequency. An optical coupler couples the first wavelength light and the second wavelength light into an interferometer cavity. An interferometer detector provides an interference measurement signal based on a detected interference pattern. A demodulator unit generates a first demodulation signal based on the interference measurement signal by demodulation with the first modulating frequency and a second demodulation signal based on the interference measurement signal by demodulation with the second modulating frequency. A computation unit computes an absolute distance by evaluating the first demodulation signal acquired during a sweep of the first tunable frequency and the second demodulation signal.

主权项

1. A device for absolute distance measurement, comprising:
a first tunable light source configured to emit a first wavelength light of a first tunable frequency modulated by a first modulating frequency; a second light source configured to emit a second wavelength light of a second frequency modulated by a second modulating frequency; an optical coupler configured to couple the first wavelength light and the second wavelength light into an interferometer cavity; an interferometer detector coupled to the interferometer cavity and configured to provide an interference measurement signal based on interferometric first and second wavelength light; a demodulator unit configured to generate a first demodulation signal based on the interference measurement signal by demodulation with the first modulating frequency and a second demodulation signal based on the interference measurement signal by demodulation with the second modulating frequency; and a computation unit configured to compute an absolute distance by evaluating the first demodulation signal acquired during a sweep of the first tunable frequency and the second demodulation signal.