04306147 is referenced by 38 patents and cites 4 patents.

Reflection-type photoelectric switching apparatus comprising a housing having a transparent front window, a light projecting device, a light receiving device arranged in side-by-side relation with the light projecting device, the light projecting and receiving devices enclosed in the housing and in a predetermined space between the devices and the front window, an optically opaque screen having a pair of transparent portions corresponding to said light projecting and receiving devices, said screen being slidably disposed in said predetermined space, an adjusting mechanism controllable from outside of the housing for driving said screen to continuously adjust an effective area of said pair of transparent portions thereof, so that a detection field defined by a common zone, in which the projected and reflected light ray bundles are crossed, is continuously variable with said adjusting mechanism.

Title
Reflection-type photoelectric switching apparatus
Application Number
6/108710
Publication Number
4306147
Application Date
December 31, 1979
Publication Date
December 15, 1981
Inventor
Hideaki Hattan
Muko
JP
Toshifumi Fukuyama
Kyoto
JP
Agent
Wegner & Bretschneider
Assignee
Omron Tateisi Electronics Co
JP
IPC
G01V 9/04
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