PMG
Optical Filters.
Luminescence Filters
Luminescence filters are used in some luminescence methods to modulate a sample's luminescence. In fluorescence microscopy, filters can help control light during imaging by defining the wavelengths of light that excite a sample and the wavelengths that are detected in the fluorescence emission. This helps collect the light from the fluorophore and avoid unwanted light from other parts of the system.
Fluorescence Filters
Excitation filters
Also called exciters, these filters allow selected light from the illuminator to pass through to the specimen when fluorescent materials are excited by ultraviolet light. In the past, excitation filters were primarily short-pass filters.
Barrier filters
These filters block or suppress excitation wavelengths and allow selected emission wavelengths to pass through to the eye or other detector.
Dichromatic beamsplitters
These filters are oriented at a 45-degree angle to the path of the excitation light entering the cube. They direct the selected excitation light through the objective and onto the specimen.
Emission filters
These filters select wavelengths that correspond to the fluorophore's emission profile. They also increase contrast by blocking autofluorescence, stray light, and reflected LED light