3475765

Information

• Patent Grant
• 3475765

• References
• Source

• Patent Number

  3,475,765

• Date Filed

  Not available

• Date Issued

  Tuesday, November 4, 1969
  55 years ago

• CPC

  • A61F9/022 - Use of special optical filters
  • A61F9/062 - with movable polarising filter discs

• US Classifications

  • 002 - Apparel
  • 250 - Radiant energy
  • 351 - Optics: eye examining, vision testing and correcting
  • 359 - Optical: systems and elements