3823313 is referenced by 23 patents and cites 5 patents.

A laser generator is mounted on a conventional transit for rotation about a vertical axis. A crank is interconnected at one end to the support structure of the transit and at its other end to the drive of an electric motor affixed to the transit and laser generator. Operation of the motor and crank causes rotational and reciprocal movement of the transit and generator about an axis to develop a datum plane of light. A control knob provides grade adjustment and is linked to a digital counter to provide a visual readout of the grade.

Title
Laser fanning device
Application Number
05/225,969
Publication Number
3823313
Application Date
February 14, 1972
Publication Date
July 9, 1974
Inventor
Unema Norman P
Agent
Price Heneveld Huizenga & Cooper
Assignee
Laser Alignment
IPC
F21v 19/02
H01S 03/02
G01C 15/00
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