3904868

Information

• Patent Grant
• 3904868

• References
• Source

• Patent Number

  3,904,868

• Date Filed

  Not available

• Date Issued

  Tuesday, September 9, 1975
  49 years ago

• CPC

  • G02B5/202 - comprising a gas or vapour
  • G02F1/178 - based on pressure effects

• US Classifications

  • 250 - Radiant energy
  • 359 - Optical: systems and elements