Heat Absorbing Glass Filter, 25.4 mm Diameter, IR Cut-off, KG-1 Glass

The FSR-KG1 Heat Absorbing Glass Filter is a 25.4 mm diameter infrared (IR) cut-off filter made of Schott KG1filter glass. Heat absorbing glass filters reduce the heat transmitted through an optical system. They have high transmission in the visible wavelength region and absorb in the IR wavelength region, making them also useful as a shortpass filter. These absorption filters are precision polished for demanding research or OEM applications.

This filter is extremely susceptible to high humidity. The filter will absorb moisture, and discoloration may happen. Please store this in a low humidity environment.

Specifications

Technical Specs

Type
Heat Absorbing Filter
Material
Schott KG1 or equivalent
Center Wavelength
VIS
Angle of Incidence
0°
Size
Ø25.4 mm
Size Tolerance
±0.3 mm
Thickness
2.0 to 3.0 mm, typical
Surface Flatness
≤1λ at 632.8 nm over the clear aperture
Surface Quality
60-40 scratch-dig

Damage Threshold
30 W/cm² CW, Typical
Wedge
≤3 arc min
Clear Aperture
central ≥ 80% of diameter
Chamfers
Up to 1 mm face width
Chamfers Angle Tolerance
45° ±15°
Cleaning
See How to Clean Optics

Type
Heat Absorbing Filter
Material
Schott KG1 or equivalent
Center Wavelength
VIS
Angle of Incidence
0°
Size
Ø25.4 mm
Size Tolerance
±0.3 mm
Thickness
2.0 to 3.0 mm, typical
Surface Flatness
≤1λ at 632.8 nm over the clear aperture
Surface Quality
60-40 scratch-dig

Damage Threshold
30 W/cm² CW, Typical
Wedge
≤3 arc min
Clear Aperture
central ≥ 80% of diameter
Chamfers
Up to 1 mm face width
Chamfers Angle Tolerance
45° ±15°
Cleaning
See How to Clean Optics

Resources & Downloads

2D Product Drawings

FBR-NDXX-S(62 kB, PDF)

Other

FSR-KG1 RoHS Certificate(705.5 kB, PDF)

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