Description of π SHINA ZnSe Precision Laser Cutting Lens
Mateial: Znse. Diameter: 20mm. Focal length: 1''/25.4mm, 1.5''/38.1mm, 2''/50.8mm, 2.5''/63.5'', 3''/76.2mm, 4''/101.6mm. Thickness:approximate 2mm. Edge thickness variation (ETV):<= 0.002''.