Bandpass filters improve contrast by allowing wavelengths within a certain range to be transmitted while blocking those outside of the pass band.
These optical filters are known as edge filters; they correspond to high and low passes in electronics.
Polarisers are used to produce polarized light. Thin-film polarisers are used in high-power applications, whereas polarisation cubes are used for simultaneous beam separation.
Photolithographic and astronomic filters are available in this section. The different optical filters available are as versatile as the applications are varied.