04818847 is referenced by 212 patents and cites 14 patents.

Apparatus for optically reading printed information by radiating light onto printed information to be reflected thereby, receiving the reflected light through an optical system and converting the image of the reflected light into a corresponding electric signal. The light source employs red light emitting diodes which radiate highly bright red light having a wavelength peak at about 660 nm so that the image sensor can receive a highly contrasting reflected light from the information printed in black on a white base. The light source further or alternatively employs infrared light emitting diodes for radiating the light having a peak wavelength at about 925 nm so that the image sensor can also received a highly contrasting reflected light from information printed in black on a blue or green base.

Title
Apparatus for optically reading printed information
Application Number
6/517745
Publication Number
4818847
Application Date
July 27, 1983
Publication Date
April 4, 1989
Inventor
Hiromitsu Takai
Obu
JP
Hiroshi Yamamoto
Anjo
JP
Tadao Oshima
Obu
JP
Toshiyasu Sakai
Kariya
JP
Atutoshi Okamoto
Chita
JP
Masahiro Hara
Kariya
JP
Agent
Cushman Darby & Cushman
Assignee
Nippondenso
JP
IPC
G06K 7/10
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