05962783 is referenced by 29 patents and cites 10 patents.

An apparatus for a rotational speed detecting includes a rotating disc having plural slits in a circumferential direction. A radiant element radiates light rays through the slits. A photodetector receives the rays radiated by the radiant element. Peak detectors detects peak points of the detected signal and a calculator calculates a rotational speed. The photodetector include two photodetectors separated by a distance .DELTA.L.

Title
Apparatus for detecting rotational speed
Application Number
8/892655
Publication Number
5962783
Application Date
July 15, 1997
Publication Date
October 5, 1999
Inventor
Tomonori Yabuta
Yokohama
JP
Yutaka Shio
Yokohama
JP
Tadashi Shinohara
Tokyo
JP
Toshiya Sato
Yokohama
JP
Mitsugu Sugiyama
Yokohama
JP
Nobuo Iwata
Sagamihara
JP
Agent
Oblon Spivak McClelland Maier & Neustadt P C
Assignee
Ricoh Company
JP
IPC
G01P 15/00
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