

Medium Film Concave Mirror, N-BK7, Operating Wavelength: 750-1100 nm CM20-F50-B
CM20-F50-BDesign Tools
View all 49 calculators →Medium Film Concave Mirror, N-BK7, Operating Wavelength: 750-1100 nm — Model CM20-F50-B
Operating wavelength 750-1100 nm, focal length -50 mm, Ø50.8 mm, substrate N-BK7.
Product Description
LBTEK dielectric-coated concave mirrors are made of N-BK7 or equivalent material, with a broadband dielectric coating on the concave surface, and can be used for beam collimation, focusing, and imaging. Currently, LBTEK offers dielectric-coated concave mirrors in three wavelength ranges: 400-750 nm, 750-1100 nm, and 1100-1650 nm. The average reflectance of these mirrors is greater than 99% within the specified wavelength range. Additionally, the dielectric-coated concave mirrors are available in seven different focal lengths ranging from -25 mm to -500 mm, with sizes of one inch and two inches. In addition to standard products, LBTEK also provides custom solutions for size, focal length, and wavelength range. If needed, please contact LBTEK technical support.
Medium Film Concave Mirror, N-BK7, Operating Wavelength: 750-1100 nm
- Operating Wavelength: 750-1100 nm
- Reflectivity: Ravg > 99%
- Focal Length: -25 mm~-500 mm
- Backside Frosted
LBTEK Dielectric Coating Concave Mirror uses N-BK7 or equivalent material as the substrate, with a broadband Dielectric Coating on the concave surface (ground backside). It can be used for beam collimation, focusing, and image. This mirror has high Reflectance (Ravg>99%) in the 750-1100 nm wavelength range. Currently, LBTEK offers Dielectric Coating Concave Mirrors in one-inch and two-inch sizes, which can be mounted in one-inch or two-inch Mirror Mounts. The available Focal Length (f) range for Dielectric Coating Concave Mirrors includes seven focal lengths from -25 mm to -500 mm. In addition to standard products, LBTEK also provides custom solution for dimensions, Focal Length (f), and wavelength range. If needed, please contact LBTEK technical support.
| Diameter | Ø50.8 mm |
| Center Thickness | 9.0 mm |
| Operating Wavelength | 750-1100 nm |
| Clear Aperture | >90% CA |
| Edge Thickness | 12.3 mm |
| Material | N-BK7 or equivalent material |
| Focal length | -50 mm |
| Reflectivity | Ravg>99%@750-1100 nm(AOI=0°- 45°) |
| Surface Quality (Scratch/Dig) | 40/20 |
| Surface irregularity | λ/4@633 nm |






