Interference Filters

Interference FiltersInterference filters pass a very narrow spectral band of visible or near-infrared light and reject all out of band wavelengths from low UV to far IR. The rejected light is either reflected back or absorbed by the filter. The typical interference filter has a bandpass of 10nm or 20 nm, in which its FWHM transmission efficiency is typically only 40-50%. Interference filters are classified by their bandpass center wavelength. Sciencetech offers a wide selection ranging from 254 to 1064 nm. Please specify requirements when ordering.

Typical Transmission Efficiency
The Minimum Peak Transmission (MPT)(%) ranges from 17% for the sub 308 nm center wavelengths to 25-50% for the 334 to 694 nm center wavelengths to 50% for the above 730 nm center wavelength filters.

Heat Tolerance
Interference filters reflect back much of the unwanted light and hence gives it a high heat tolerance. Whether in the Visible or IR spectral region, they can typically tolerate up to 0.75W/cm2 of light power on them. This is the total light power shining on the filter and not the portion that is being absorbed by the filter. This is based on an uncooled filter.
Center Wavelength Ranging 254 to 308nm @17%MPT5675
Center Wavelength Ranging 334 to 410nm @25-30%MPT562530
Center Wavelength Ranging 420 to 694nm @40-50%MPT564050
Center Wavelength Ranging 650 to 1064nm @50%MPT5650