Polarization-independent spatial light self-homodyne interferometer

The invention belongs to the technical field of free space optical communication equipment, and discloses a polarization-independent spatial light self-homodyne interferometer. Comprising a first beam splitting interface, a first reflection interface, a second reflection interface, a first polarization beam splitting interface, a second polarization beam splitting interface, a second beam splitting interface, a third beam splitting interface, a third reflection interface, a fourth reflection interface, a first half-wave plate, a second half-wave plate, a third half-wave plate, a first quarter-wave plate and a second quarter-wave plate. Compared with the prior art, polarization beam splitting is carried out on the first signal light and the second signal light which have the time difference after beam splitting is carried out on the input signal light, so that two polarization components of the first signal light and the second signal light interfere with each other and then are subjected to polarization beam