Optical detection system and operation method thereof

An optical detection system is configured to detect a component under test having a first linear polarizer and a quarter-wave plate. The optical detection system comprises a light source, a polarization adjustment assembly and a detection unit. The light source has a light emitting surface and is configured to emit light. The polarized light adjusting assembly faces the light-emitting surface of the light source. The polarization adjustment assembly is configured to convert the light into linear polarized light. The first linear polarizer is located between the polarization adjusting assembly and the quarter-wave plate. The to-be-tested component is configured to convert the linearly polarized light into circularly polarized light. The detection unit is located on the side, back to the polarization adjustment assembly, of the to-be-detected assembly. The detection unit is configured to calculate a phase difference angle between an absorption axis of a first linear polarizer of the to-be-detected assembly and