3556664

Information

• Patent Grant
• 3556664

• References
• Source

• Patent Number

  3,556,664

• Date Filed

  Not available

• Date Issued

  Tuesday, January 19, 1971
  54 years ago

• CPC

  • G01N21/8916 - for testing photographic material
  • G01N21/8901 - Optical details; Scanning details
  • G03B35/24 - using apertured or refractive resolving means on screens or between screen and eye

• US Classifications

  • 356 - Optics: measuring and testing
  • 250 - Radiant energy