Dichroic Filters, also known as Dichroic Mirrors or Dichromatic Mirrors, are coated with thin-film dielectric coatings that transmit wavelengths within a specified transmission band and reflect all other wavelengths. By reflecting rejected wavelengths instead of absorbing them, dichroic filters can be used with more intense light sources than absorptive filters. Dichroic Filters are generally used at a 45° angle of incidence to reflect rejected light at 90° to the transmitted light. Dichroic Filters are used in applications such as fluorescence microscopy and flow cytometry to selectively transmit light towards detectors.

Edmund Optics offers a range of Dichroic Filters, including 45° Reflective Dichroic Color Filters that reflect one color while transmitting all other visible wavelengths, Dichroic Shortpass Filters and Dichroic Longpass Filters designed for the visible or near-infrared (NIR), and Fluorescence Dichroic Filters with cut-on wavelengths at common fluorophore emission wavelengths. For more information on our optical filter products, visit our Optical Filters Selection Guide.