3817614

Information

• Patent Grant
• 3817614

• References
• Source

• Patent Number

  3,817,614

• Date Filed

  Not available

• Date Issued

  Tuesday, June 18, 1974
  50 years ago

• CPC

  • G09B1/20 - and bearing the symbols on a surface parallel to the axis of rotation

• US Classifications

  • 353 - Optics: image projectors
  • 355 - Photocopying
  • 434 - Education and demonstration