2163205

Information

• Patent Grant
• 2163205

• References
• Source

• Patent Number

  2,163,205

• Date Filed

  Not available

• Date Issued

  Tuesday, June 20, 1939
  85 years ago

• CPC

  • G01J1/40 - using limit or visibility or extinction effect

• US Classifications

  • 356 - Optics: measuring and testing
  • 235 - Registers