Double-Concave (DCV) Lenses have two inward curved surfaces and a negative focal length. They are used for image reduction and to spread light.
They are also useful in a variety of applications involving beam expansion, beam projection, and expand the focal length of optical system.
Material: Optical Glass, CaF2, MgF2, Fused Silica/Ge, Sapphire……
Size Range: 0.5-500mm
Dimension Tolerance: +/-0.02mm
Surface Quality: 40/20-10/5
Radius Tolerance: +/-0.1%
Irregularity: 1/4-1/10 Lambda
Centering: <1 arcmin
EFL Tolerance: +/-1%
Clear Aperture: >95%
Coating: AR, BBAR, VIS, NIR, HR, VIS, NIR
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