Standard Hot / Cold Mirrors
  • Heat removal at either normal or 45°incidence
  • Hard, high durability coatings
  • High temperature operation to 500°C
  • Available in 25.4 mm diameter and 50.8 mm square sizes.

Product Description

Both hot and cold mirrors can be used to remove heat from an optical system. Heat-reflecting mirrors/filters (hot mirrors) are designed to operate a normal incidence and transmit visible wavelengths while reflecting near-infrared heat generating wavelengths. Heat-transmitting mirrors/filters (cold mirrors) are designed to reflect visible wavelengths while transmitting near-infrared heat-generating wavelengths. Our hot mirrors are designed for use at normal incidence and our cold mirrors are designed for 45° angle of incidence. Both product types are available in 25.4 mm diameter and 50.8 mm square sizes.

To discuss your specific requirements, please call 508-528-4411 to speak directly to one of our Technical Sales Engineers, or email us at

Ordering Information

10HMR-0 Heat Control Filter, 25.4 Dia, 0° Hot Mirror
20HMS-0 Heat Control Filter, 50.8 x 50.8mm, 0° Hot Mirror
10CMR-45Heat Control Filter, 25.4 Dia, 45° Cold Mirror
20CMS-45Heat Control Filter, 50.8 x 50.8mm, 45° Cold Mirror


MaterialBorofloat® borosilicate float glass
Surface Flatness6–8λ per 25.4 mm at 546.1 nm over the clear aperture
Clear Aperture≥central 90% of dimensions
Surface Quality80-50 scratch-dig
Dimension Tolerance±0.4 mm
Thickness3.3 ±0.2 mm
S2 CoatingNone
Temperature500 °C maximum
CleaningNon-abrasive method, acetone or isopropyl alcohol on lens tissue recommended


TypeWavelengthReflectance / TransmittanceAngle of Incidence
Hot Mirror200–390 nmTavg≤1.0%0°±15°
Hot Mirror420–690 nm Tavg≥85%0°±15°
Hot Mirror725–1550 nmRavg≥90%0°±15°
Cold Mirror400–700 nmRavg≥95%45°±15°
Cold Mirror780–1250 nmTavg≥85%45°±15°
Cold Mirror 850–2500 nmTavg≥80%45°±15°