公开(公告)号：WO1982002104A1

公开(公告)日：1982-06-24

申请号：PCT/US1981001622

申请日：1981-12-03

Applicant: NCR CORP

Inventor： NCR CORP ,  GORIN BRIAN A ,  HARDY JAMES A

IPC: G06K07/10

CPC classification number: G06K7/10871 ,  G02B26/106 ,  G06K2207/1013

Abstract: In a holographic scanning system suitable for scanning bar code indicia, a light beam (54) provided by a laser source (20) is directed to a first set of holograms (42, 44, 46) located on a rotating disc (26), each hologram generating an individual scan beam having a slightly different focal length and direction angle from that of the other holograms. The scan beams are projected such that the depth of focus portions (D u) of the projected beams overlap so as to provide an enhanced depth of focus for the scanning operation, thereby alleviating the problem of precisely positioning the object to be scanned, and enabling a more effective scanning operation. The light reflected from the bar code is collected by a second set of holograms (48, 50, 52) on the scanning disc arranged to focus the received light at a collection point (62) on an optical detector.

Abstract translation: 在适于扫描条形码标记的全息扫描系统中，由激光源（20）提供的光束（54）被引导到位于旋转盘（26）上的第一组全息图（42,44,46） 每个全息图产生具有与其它全息图的焦距和方向角略微不同的单个扫描光束。 投影扫描光束使得投影光束的焦深部分（D u）重叠，从而为扫描操作提供增强的聚焦深度，从而减轻精确定位被扫描物体的问题 ，并且能够进行更有效的扫描操作。 从条形码反射的光被扫描盘上的第二组全息图（48,50,52）收集，该第二组全息图被布置成将接收的光聚焦在光学检测器上的收集点（62）上。