Filter

Filter


Optical Filters are used to selectively transmit or reject a wavelength or range of wavelengths. Optical Filters are used in applications such as fluorescence microscopy, spectroscopy, clinical chemistry, or machine vision inspection. Optical Filters are ideal for life science, imaging, industrial, or defense industries.


Key Optical Filter Terminology

Central Wavelength  (CWL) Center Wavelength is the midpoint between the wavelengths where transmittance is 50% of the specified minimum transmission
FWHM Full Width at Half Maximum 
Bandwidth Bandwidth is a wavelength range used to denote a specific part of the spectrum that passes incident energy through a filter. 
Blocking Range Blocking Range is a wavelength interval used to denote a spectral region of energy that is attenuated by the filter
Cut-On Wavelength Cut-On Wavelength is a term used to denote the wavelength at which the transmission increases to 50% throughput in a longpass filter.
Cut-Off Wavelength Cut-Off Wavelength is a term used to denote the wavelength at which the transmission decreases to 50% throughput in a shortpass filter.