E-49-932 20mm Dia. x 25mm FL, MgF2 Coated, Achromatic Doublet Lens
E-49932 20mm Dia. x 25mm FL, MgF2 Coated, Achromatic Doublet Lens
Diameter (mm): 20.00 +0.0/-0.025
Effective Focal Length EFL (mm): 25.00
Focal Length Tolerance (%): ±2
Back Focal Length BFL (mm): 18.71
Focal Length Specification Wavelength (nm): 587.6
Clear Aperture CA (mm): 19.00
Centering (arcmin): <1
Center Thickness CT 1 (mm): 9.50
Center Thickness CT 2 (mm): 2.50
Center Thickness Tolerance (mm): ±0.2
Radius R1 (mm): 18.03
Radius R2 (mm): -13.27
Radius R3 (mm): -55.46
Edge Thickness ET (mm): 8.06
Surface Quality: 40-20
f/#: 1.25
Numerical Aperture NA: 0.40
Coating: MgF2 (400-700nm)
Coating Specification: Ravg ≤1.75% @ 400 - 700nm
Power (P-V) @ 632.8nm: 1.5λ
Irregularity (P-V) @ 632.8nm: λ/4
Bevel: Protective bevel as needed
Type: Achromatic Lens
Wavelength Range (nm): 400 - 700