Infrared Neutral Density Filters
Metallic-coated neutral density (ND) filters obtain their optical density from a metal alloy coating on a substrate determined by the wavelength region of interest. Unlike the all-dielectric or absorption type, the metallic type ND filter employs a combination of absorption and reflection to reduce the intensity of light.
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| General Specifications | |
|---|---|
| Thickness: | 1.0mm |
| Dimesnional Tolerance: | ±0.2mm |
| Clear Aperture: | 90% of outside diameter |
| Surface Quality: | 60/40 per MIL-O-13830B |
| Coating Adherence: | per MIL-M-13508C |
| Humidity: | per MIL-STD-810F |
| Mechanical: | Not mounted in metal holder |
| Substrate Material: | Germanium |
| Optical Quality: | Flatness of 3 to 5 waves per
inch and parallelism of 10 arc minutes or better |
Metallic Neutral Density Filters
(2.0µm to 14µm) |
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|---|---|---|---|
| Part Numbers (Click to check price and availability) | |||
Optical Density |
Nominal Transmittance (%) |
25mmØ |
50mmØ |
| 0.30 | 50.00 | 030FNIR-25 | 030FNIR-50 |
| 0.50 | 31.62 | 050FNIR-25 | 050FNIR-50 |
| 1.00 | 10.00 | 100FNIR-25 | 100FNIR-50 |
| 2.00 | 01.00 | 200FNIR-25 | 200FNIR-50 |
| 3.00 | 00.10 | 300FNIR-25 | 300FNIR-50 |
Note: Custom sizes and densities available on request. Contact our technical sales department for a quotation.