Granted Patent
Utility
US 4,273,843 · App. 06/045,759
Method of detecting toner concentration in electrophotographic copying machine
Inventors:
Hisao Fujita, Kiyoshi Kimura
Patented Case
View Patent ↗
Granted: Jun 16, 1981
Filed: Jun 5, 1979
Inventors
Hisao Fujita
Kiyoshi Kimura
Assignee (at issue)
Konishiroku Photo Industry Co., Ltd.
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.