A long pass (LP) filter is an optical interference or colored glass filter that attenuates shorter wavelengths and transmits (passes) longer wavelengths over the active range of the target spectrum (ultraviolet, visible, or infrared). Long pass filters, which can have a very sharp slope (referred to ......
A short pass (SP) Filter is an optical interference or colored glass filter that attenuates longer wavelengths and transmits (passes) shorter wavelengths over the active range of the target spectrum (usually the ultraviolet and visible region). In fluorescence microscopy, short pass filters are frequ......
Band-pass filters only transmit a certain wavelength band and block others. 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 nanometers. Such a filter can be made by combining an LP- and an SP filter. Band-pass filters are often used in astronomy when one wants to observe a certain process with specific associated spectral lines.......
