3675993

Information

• Patent Grant
• 3675993

• References
• Source

• Patent Number

  3,675,993

• Date Filed

  Not available

• Date Issued

  Tuesday, July 11, 1972
  52 years ago

• CPC

  • G09B9/304 - by using a film
  • G03B31/02 - in which sound track is on a moving-picture film
  • G09B9/08 - for teaching control of aircraft

• US Classifications

  • 352 - Optics: motion pictures
  • 434 - Education and demonstration