The definition of Bandpass filters is that they are designed to selectively transmit light over a certain wavelength band while blocking the remaining light in a given spectrum. The width of such a filter is expressed in the wavelength range it lets through and can be anything from much less than an Ångström to a few hundred nanometer. These filters are referred to as narrow bandpass optical filters, and are typically and extensively used in the life science, industrial, Medical appliances, photography, or Research and Developing (R&D) applications.
Hangzhou Shalom EO offers Bandpass Filters for Biochemistry Analyzers, Narrow Bandpass Filters for Enzyme Labelling Instrument, Narrow Bandpass Filters for Polarimeter, Fluorescence filters, Ultra-Violet (UV) Narrow Bandpass Filters and High Transmission Narrow Bandpass filter made from Colored Glass bonded with BK7 or Fused Silica (the glass we sourced are equivalent to that of Hoya). There is a wide selective blocking wavelength range of 200-1200nm, from Ultra-Violet (UV) to Visible and the Infrared (IR) spectrum, with a conventional bandwidth of 10nm (narrower bandwidths could be obtained upon request). Dozens of mounted stock modules with a diameter range of 6-15mm, hard coatings are for choosing. Shalom EO also designs customized optical filters of which you could specify the parameters.