Light source relative intensity noise suppression device based on F-P cavity

Abstract

The invention discloses a light source relative intensity noise suppression device based on an F-P cavity. Light output by the wide-spectrum light source passes through the optical isolator and the 2 * 2 optical coupler, then reaches the polarization maintaining optical fiber, and then sequentially passes through the optical circulator, the polarization rotator and the optical circulator to reach the first optical fiber reflection film to be reflected and transmitted. Transmission light is output, reflected light is reversely reflected and then sequentially passes through the optical circulator, an optical amplifier, the optical circulator, the polarization maintaining optical fiber and the 2 * 2 optical coupler to be respectively coupled into the optical isolator and a second optical fiber reflection film, the light coupled to the optical isolator is dissipated, and the light coupled to the second optical fiber reflection film is reflected and transmitted again; and transmission light is dissipated, reflected light returns and is coupled to the 2 * 2 optical coupler again, and light source light output and relative intensity noise suppression are achieved continuously in a reciprocating mode. According to the invention, while the relative intensity noise of the light source under the specific frequency is reduced, the length of the optical fiber utilized by the resonant cavity is shortened, and the detection noise of the frequency with reduced relative intensity noise after spectral filtering of the Sagnac interferometer is reduced.

Description

technical field [0001] The invention relates to a light source noise suppression device in the technical field of fiber optic gyroscopes, in particular to a fiber optic gyroscope relative intensity noise suppression device based on an F-P cavity. Background technique [0002] Broad-spectrum light sources are widely used in optical interferometry. It has a micron-level coherence length, which effectively eliminates the error caused by the Kerr effect in the Sagnac interferometer. But at the same time, the wide-spectrum light source introduces relative intensity noise, which limits the random walk and bias drift characteristics of high-precision fiber optic gyroscope angular velocity measurement. [0003] Many units at home and abroad have adopted a variety of methods to suppress the relative intensity noise of the solid line, mainly including expanding the spectral width, designing a feedback link to control the driving current of the light source or a high-speed light inten...

AI Technical Summary

Problems solved by technology

[0005] The technical problem solved by the present invention is to reduce the relative intensity noise level of the fiber optic gyroscope, and proposes a light source relative intensity noise suppression device based on an F-P cavity.

Images