Dichroic Filters, or Interference Filters are precise color filters that transmit light from a narrow range of colors while reflecting the other unwanted portion. Dichroic filters split light into two components, one component is transmitted and one is reflected. Using a Dichroic filter, a user can select spectral regions of interest and decide whether the separated light spectrum should be utilized or dumped. Dichroic filters function based on the principles of interference, where dielectric thin film coatings are deposited on the filter substrates to obtain constructive interference for certain wavelengths of light and destructive interference for others. A long-pass dichroic filter has a high reflectance below the cut-on wavelength and a high transmittance above it. Because the unwanted portion of the light is reflected instead of absorbed by the filters, dichroic longpass filters can endure light sources with higher intensities. 

North Optics offers Longpass Dichroic Filters, utilizing a combination of cutting-edge production techniques and stringent control of qualities, these filters boast a sharp cut-on slope that offers optimum optical selection and exception durabilities. Various dichroic filters with wide operation wavelengths are also available in Shanghai North Optics including long pass filters, short pass filters, dichroic bandpass filters, dichroic band stop (notch) filters, and filters for color correction. our dichroic filters serve as excellent components to separate color in CCD imaging, digital projection, light show, machine vision, and printing. These filters allow only a wanted portion of the spectrum to pass and reject (reflect) the rest. Dichroic shortpass filters can be utilized as hot mirrors and longpass dichroic filters as cold mirrors.