Plano-convex lens φ5mm Focal length: 20mm Back focus: 18.8mm Material: B270 1 piece

An optical lens with a positive focal length that is primarily used for image magnification, focusing, and collimation. In general use, the curved side of the lens faces the subject. Material: B270 Outer diameter (φmm): 5 Focal length (mm): 20 Back Focus (mm): 18.8 Medium thickness (mm): 2 Edge thickness (mm): 1.72 Design wavelength: 587.6nm Refractive index: 1.523/nd Chamfer (45°): 0.1mm <Tolerance range> Outer diameter: φ+0/-0.1mm Center thickness: ±0.2mm Focal length: ±2% Surface quality: MIL60-40 Eccentricity: Within 3 minutes (3') *When using as a collimating lens, use it in the opposite direction.