Plano-concave lens, Fused silica, Ø 22.4 mm, f = -40 mm, ARB2-VIS

Plano-concave singlet in Fused silica, Ø 22.4 mm, focal length -40 mm. ARB2-VIS broadband AR coating. Negative focal length: diverges the beam, for beam expanders and to shorten system length.