Longpass Filters

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A longpass (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). Longpass filters, which can have a very sharp slope (referred to as edge filters), are described by the cut-on wavelength at 50 percent of peak transmission. In fluorescence microscopy, longpass filters are frequently utilized in dichroic mirrors and barrier (emission) filters. Use of the older term 'low pass' to describe longpass filters has become uncommon; filters are usually described in terms of wavelength rather than frequency, and a "low pass filter", without qualification, would be understood to be an electronic filter.

Check with our sales engineers for Longpass Filters for detailed.

Attribute Specification
Material Optical Glass
Optical Density OD ≥3.0
Coating: Traditional Coated
Clear Aperture CA (mm): 85%CA
Operating Temperature (°C): -62 to +71
Surface Quality 60-40
Thickness (mm): 1.00 ±0.2
Cut-On Tolerance (%): 5% of Peak Transmission
Surface Flatness: 3 - 5λ