How To Specify A Filter

The optical filter specifications required will depend on the filter application and how it is to be used. In general, typical filter optical specifications will include the wavelength ranges over which to reflect and transmit light, angle of incidence tuning range, clear aperture of the filter, the polarization state of light for non-normal angles of incidence, light coherency (laser or white light), optical beam size and cone angle of light, desired substrate material (with dimensions), incident light medium (air or glass) and so forth. In addition, physical specifications such as the operating temperature range and the ambient environment of the filter should also be specified.