公开(公告)号：US3812459A

公开(公告)日：1974-05-21

申请号：US23289372

申请日：1972-03-08

申请人： OPTICAL BUSINESS MACHINES

发明人： MAC NEIL J ,  WILLEY R

IPC分类号： G06K7/10 ,  G02B27/00 ,  G06K9/00 ,  G06K9/20 ,  G06T1/00 ,  G06K9/10

CPC分类号： G06K9/2009

摘要： An optical arrangement for character recognition systems utilizes the same optical path for both illuminating the text and projecting the text onto an array of photosensitive elements. A low power laser beam of cross-section slightly larger than a unit vertical slice of a text character is projected by a prism through a lens arrangement to a scanning mirror which reflects the beam to sequentially illuminate individual text character slices. Each illuminated slice is reflected by the mirror through the lens arrangement onto a linear array of photosensitive elements. The focus of the lens arrangement is varied in synchronization with the mirror scan to correct for changes in the distance between the mirror and text characters at different scan angles. The page is oriented at a slight angle relative to the scan axis of the mirror to eliminate specular reflection. The resultant skew created in the reflected characters as a function of scan angle is compensated for by rotating the photosensitive array about the optical path axis as a function of mirror scan angle.