1550nm polarization-maintaining filter coupler is an optical device, which is used to keep the polarization direction of the optical signal stable and perform the functions of optical filtering and optical coupling at the same time. It mainly consists of two functional components: polarization maintaining filter and optical coupler.

Polarization-maintaining filter is an optical device that can separate or filter the vertically or horizontally polarized light in the incoming optical signal, and only retain the required polarized light signal. Polarization-maintaining filters are usually made of birefringent crystals with high refractive index difference. By adjusting parameters such as the thickness and angle of the crystals, selective filtering of optical signals with specific wavelengths and polarization directions can be achieved.

By combining polarization maintaining filter and optical coupler, 1550nm polarization maintaining filter coupler can realize polarization maintaining filtering and optical coupling of optical signals, and has excellent polarization maintaining performance, filtering effect, coupling efficiency and stability. It has a wide range of applications in optical communication, optical sensing, quantum communication and other fields.