TWO-DIMENSIONAL BAR CODE LASER MARKING METHOD
 Inventor: Feng-Yu Xu, Chiba-ken, Japan
 Assignee: Miyachi Technos Corporation,
 Appl. No.: 09/203,381
 Filed: Dec. 2, 1998
 Foreign Application Priority Data
Dec. 3, 1997 [JP] Japan 9-348624
 Int. CI.7 B23K 26/00
 U.S. CI 219/121.69; 219/121.8;
 Field of Search 219/121.68, 121.69,
219/121.8, 121.74; 235/462.09, 494
 References Cited
U.S. PATENT DOCUMENTS
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5,481,100 1/1996 Terauchi 235/494
5,546,214 8/1996 Black et al 219/121.74
5,637,850 6/1997 Honda .
5,907,144 5/1999 Poon et al. .
5,932,119 8/1999 Kaplan et al 219/121.68
Primary Examiner—Geoffrey S. Evans
Attorney, Agent, or Firm—-Wenderoth, Lind & Ponack,
In marking execution mode, after initialization, a scanning control signal based on predetermined marking data and condition data is sent to a scanning head so that a beam spot of a YAG laser beam scans spirally on the interior of a predetermined first black cell in a two-dimensional bar code marking region on the surface of a workpiece W. After the completion of the spiral scanning on the interior of the first black cell, the beam spot skips over from the scanning end point to a scanning start point of a second black cell adjacent to that end point. Then, the interior of the second black cell is also scanned with the beam spot in a unit plotting pattern similar to the above. Afterward, the same spiral scanning as the above is iteratively made on a third and all subsequent black cells. Upon the completion of the spiral scanning on the last black cell, all the marking actions are complete.
4 Claims, 13 Drawing Sheets