Optical Instrument Lens

Features

Specifications

• Diameter:
  Between 1.297 inches and 1.300 inches
• Axial Thickness:
  Between 0.200 inches and 0.220 inches
• Equivalent Focal Length:
  3.859 inches
• Back Focal Length:
  3.759 inches
• Refraction Index:
  1.6170
• Abbe Constant:
  55.000
• Single Lens Style:
  Double convex
• Element Left Surface Radius:
  3.100 inches
• Element Right Surface Radius:
  10.000 millimeters
• Material:
  Glass, optical, mil-g-174, class 1, grade d, type 617-550
• Fsc Application Data:
  Periscope, tank
• Federal Supply Class (fsc):
  Optical instruments, test equipment, components and accessories
• National Stock Number (nsn):
  6650-00-768-8774
• Special Features:
  Edges chamfered 0.010 to 0.020 in. By 45 deg. Both surfaces coated with magnesium fluoride. Rim ground.