Sorry, this product is no longer offered for sale. It was discontinued on Feb 14, 2025The recommended replacement product is FSR-KG3-C.
Heat Absorbing Glass Filter, 25.4 mm Diameter, IR Cut-off, KG-3 Glass

The FSR-KG3 Heat Absorbing Glass Filter is a 25.4 mm diameter 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.
Resources & Downloads
2D Product Drawings
FBR-NDXX-S(62 kB, PDF)
Other
FSR-KG3 RoHS Certificate(706.3 kB, PDF)
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