A depolarization splitting prism is a cube structure formed by coating multiple layers of interference films on the inclined surface of one of the right angle prisms and bonding them together, so that the incident light has similar splitting characteristics for the P-polarization and S-polarization components. Generally, under non perpendicular incidence, the film layer will produce polarization effects. When the incident light passes through the interference film layer of the bonded prism, strong polarization effects will also be produced, which is very harmful in many optical path systems. The depolarization splitting film is designed to minimize the polarization effects of these P and S-polarization states, maintain the maximum input angle of the polarizing film performance, and try to maintain the original proportion of horizontal and vertical polarization in the incident light source as much as possible, The optical properties of P light and S light have a separation degree less than a certain value, low dispersion, good color neutrality, and a wavelength range covering 230-2500nm. They are widely used in various imaging instruments.