Cold Mirror, 50.8 x 50.8 mm, 45° AOI, 780-2500 nm Transmittance

The 20CMS-45 Cold Mirror is a 50.8 x 50.8 mm square 45° mirror used as a heat control filter. Our cold mirrors are heat-transmitting longpass filters designed to reflect 400-700 nm visible wavelengths while transmitting 780-2500 nm near-infrared wavelengths. These filters can be used to remove heat from an optical system.

Specifications

Technical Specs

Type
Cold Mirror
Optic Size
50.8 x 50.8 mm
Transmittance Range
780-2500 nm
Transmission
Tavg≥85% 780-850 nm; Tavg≥80% 850-2500 nm
Reflectance Band
400-700 nm
Reflectance
Ravg≥95%
Angle of Incidence
45° ±5°
Material
Borofloat® borosilicate float glass
Surface Quality
80-50 scratch-dig

Surface Flatness
6–8λ per 25.4 mm at 546.1 nm over the clear aperture
Thickness
3.3 mm
Thickness Tolerance
±0.2 mm
Size Tolerance
±0.4 mm
Clear Aperture
≥central 90% of dimensions
Temperature Range
-100 to 500°C
Cleaning
See How to Clean Optics

Type
Cold Mirror
Optic Size
50.8 x 50.8 mm
Transmittance Range
780-2500 nm
Transmission
Tavg≥85% 780-850 nm; Tavg≥80% 850-2500 nm
Reflectance Band
400-700 nm
Reflectance
Ravg≥95%
Angle of Incidence
45° ±5°
Material
Borofloat® borosilicate float glass
Surface Quality
80-50 scratch-dig

Surface Flatness
6–8λ per 25.4 mm at 546.1 nm over the clear aperture
Thickness
3.3 mm
Thickness Tolerance
±0.2 mm
Size Tolerance
±0.4 mm
Clear Aperture
≥central 90% of dimensions
Temperature Range
-100 to 500°C
Cleaning
See How to Clean Optics

Resources & Downloads

Other

20CMS-45 RoHS Certificate(264.3 kB, PDF)
20CMS-45_ROHS2-2021.pdf(280.2 kB, PDF)

Related Products

Similar

Description	Compatibility	Price
20HMS-0Hot Mirror, 50.8 x 50.8 mm, 0° AOI, 420-690 nm Transmittance	UNIVERSAL	$79
10HMR-0Hot Mirror, 25.4 mm, 0° AOI, 420-690 nm Transmittance	UNIVERSAL	$59
10CMR-45Cold Mirror, 25.4 mm, 45° AOI, 780-2500 nm Transmittance	UNIVERSAL	$46

Compatible

Description	Compatibility	Price
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CYM-2RCylindrical Lens Mount, Adjustable, 50.8 mm Max, +/- 5 Deg., 2 arcs sec	UNIVERSAL	$211