bi-concave lens element / BK7 / fused silica / CaF2
BK7, fused silica, CaF2, germanium
12.7 mm, 25.4 mm (0.5 in)
The Double-Concave Lenses have Lower spherical aberrations than for Plano-Concave lenses with Diverges incident light. This product is Ideal for Experimenting and Prototyping Applications. It is made up of BK7, FS, UVFS, CaF2, ZnSe, Si, and Ge. For additional specifications, the design wavelength is 632.8 nm with focal length tolerance of ±3 %. The surface quality is 40/20 S/D while the surface figure is <λfirstname.lastname@example.org nm. These lenses also work as beam expanders, optical character readers, viewers and projection systems.