The invention discloses
heterodyne technology based device and method for testing the half-wave
voltage of a phase modulator. The device comprises a
laser, a first 50-percent coupler, a phase modulator, an acousto-optic
frequency shifter, a second 50-percent coupler, a photoelectric
detector, a vector analyzer, a first
signal generator and a second
signal generator; the
laser is sequentially connected with the first 50-percent coupler, the phase modulator, the second 50-percent coupler, the photoelectric
detector and the vector analyzer, the first 50-percent coupler is sequentially connected with the acousto-optic
frequency shifter and the second 50-percent coupler, the phase modulator is connected with the first
signal generator, and the acousto-optic
frequency shifter is connected with the second
signal generator. The invention provides the method for accurately testing the half-wave
voltage of the phase modulator, the carrier component in
phase modulation can be effectively inhabited by utilizing the half-wave
voltage obtained through testing, the back-scattered
noise in a
resonance type
optical gyroscope is reduced, the invention provides a feasible method for improving the precision of the
resonance type
optical gyroscope and has important scientific meanings and application value.