2197194

Information

• Patent Grant
• 2197194

• References
• Source

• Patent Number

  2,197,194

• Date Filed

  Not available

• Date Issued

  Tuesday, April 16, 1940
  84 years ago

• CPC

  • G03B7/04 - Control effected by hand adjustment of a member that senses indication of a pointer of a built- in light-sensitive device
  • G01J1/14 - using comparison with a surface of graded brightness

• US Classifications

  • 396 - Photography