A filter bonded prism is a cube made of a pair of high-precision right angled prisms coated with special optical thin films and bonded together. It is a type of prism that allows light of a specific wavelength to pass through while reflecting or attenuating light of other wavelengths. Filter bonded prisms have the advantages of high transmittance, extremely low loss, high stability, and extremely narrow transition bands, and are widely used in the optical, electronic, and biomedical fields.