Optical Instrument Lens

Features

Specifications

• Diameter:
  Between 2.498 inches and 2.500 inches
• Axial Thickness:
  Between 0.3269 inches and 0.3369 inches
• Equivalent Focal Length:
  4.728 inches
• Back Focal Length:
  4.385 inches
• Single Lens Style:
  Meniscus converging
• Material:
  Glass, optical, mil-g-174, grade a and glass, optical, mil-g-174, grade b
• Federal Supply Class (fsc):
  Optical instruments, test equipment, components and accessories
• National Stock Number (nsn):
  6650-01-202-0596
• Special Features:
  Lens no. 6, biocular eyepiece; matl: optical glass (lafn2) per mil-g-174, grade a/b, stain 4, fine anneal, type 744-448 (802199-43); r1, 1.955 radius of lens outside (left) surface; r2, 4.0645 radius of lens inside (right) surface; 0.180 dist between base and inside axis; used in biocular assembly on comm and gun disp