Optical Instrument Lens

Features

Specifications

• Diameter:
  Between 38.7 millimeters and 39.2 millimeters
• End Application:
  Rangefinder mk57
• Axial Thickness:
  8.2 millimeters and 4.0 millimeters
• Compound Lensaxial Thickness:
  12.2 millimeters
• Equivalent Focal Length:
  36.360 centimeters
• Back Focal Length:
  36.400 centimeters
• Front Focal Length:
  35.040 centimeters
• Refraction Index:
  1.5170 and 1.6210
• Abbe Constant:
  64.800 and 36.200
• Compound Lens Style:
  Doublet
• Individual Lens Style:
  Double convex and meniscus diverging
• Element Left Surface Radius:
  186.2 millimeters and -155.5 millimeters
• Element Right Surface Radius:
  155.5 millimeters and 1001.8 millimeters
• Material:
  Glass, optical, jan-g-174
• Federal Supply Class (fsc):
  Optical instruments, test equipment, components and accessories
• National Stock Number (nsn):
  6650-00-155-1361