Optical Instrument Lens

Features

Specifications

• Diameter:
  2.598 inches
• Axial Thickness:
  0.394 inches and 0.394 inches
• Compound Lensaxial Thickness:
  0.787 inches
• Compound Lens Edge Thickness:
  0.746 inches
• Equivalent Focal Length:
  18.905 inches
• Back Focal Length:
  18.424 inches
• Front Focal Length:
  18.890 inches
• Refraction Index:
  1.5724 and 1.6168
• Abbe Constant:
  57.400 and 36.600
• Compound Lens Style:
  Doublet
• Individual Lens Style:
  Double convex and meniscus diverging
• Material:
  Glass, optical, jan-g-174, grade c
• Fsc Application Data:
  Fire control, periscope mk30 mod 2
• Federal Supply Class (fsc):
  Optical instruments, test equipment, components and accessories
• National Stock Number (nsn):
  6650-00-382-1958