Heat Absorbing Glass Filter, 50.8 x 50.8 mm, IR Cut-off, KG-3 Glass

The FSQ-KG3 Heat Absorbing Glass Filter is a 50.8 x 50.8 mm infrared (IR) cut-off filter made of Schott KG3 filter 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
- TypeHeat Absorbing Filter
- MaterialSchott KG3 or equivalent
- Center WavelengthVIS
- Angle of Incidence0°
- Size50.8 x 50.8 mm
- Size Tolerance±0.3 mm
- Thickness2.0 to 3.0 mm, typical
- Surface Flatness≤2λ at 632.8 nm over the clear aperture
- Surface Quality60-40 scratch-dig
- Damage Threshold30 W/cm2 CW, Typical
- Wedge≤3 arc min
- Clear Aperturecentral ≥ 80% of area
- ChamfersUp to 1 mm face width
- Chamfers Angle Tolerance45° ±15°
- Cleaning

Resources & Downloads
2D Product Drawings
COLOREDG-S(61 kB, PDF)
Other
FSQ-KG3 RoHS Certificate(707.8 kB, PDF)
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