Infrared Neutral Density Filter, 25.4 mm, 2.0 OD, ±3% Tolerance

The FIR-ND20 Infrared Neutral Density Filter is a 1 inch (25.4 mm) diameter infrared neutral density filter with an optical density of 2.0, and ±3% transmittance tolerance. Optimized for 2 to 5 μm, this filter attenuates IR radiation from 2 to 14 μm. It is made from a germanium substrate and is coated with a spectrally neutral vacuum deposited metal alloy reflective coating.

Specifications

Technical Specs

Size
Ø25.4 mm
Wavelength Range
2000-5000 nm
Optical Density
2
Transmission
1% @ 3.5 μm
Transmission Tolerance
±0.15%
Material
Optical grade germanium

Size Tolerance
±0.2 mm
Thickness
1.0 mm
Thickness Tolerance
± 0.2 mm
Surface Quality
80-50 scratch-dig
Clear Aperture
All but 1.5 mm outer rim
Parallelism
3 to 5 arc min (0.8 to 1.5 mrad)

Size
Ø25.4 mm
Wavelength Range
2000-5000 nm
Optical Density
2
Transmission
1% @ 3.5 μm
Transmission Tolerance
±0.15%
Material
Optical grade germanium

Size Tolerance
±0.2 mm
Thickness
1.0 mm
Thickness Tolerance
± 0.2 mm
Surface Quality
80-50 scratch-dig
Clear Aperture
All but 1.5 mm outer rim
Parallelism
3 to 5 arc min (0.8 to 1.5 mrad)

Resources & Downloads

3D Product Models

Other

FIR-ND20 RoHS Certificate(265 kB, PDF)

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Compatible

Description	Compatibility
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