Recording and reproducing device and objective lens for recording and reproducing optical information on recording media,申请号EP19950117380-传众专利搜索

Recording and reproducing device and objective lens for recording and reproducing optical information on recording media

申请公布号：EP0725394(A2)

申请号：EP19950117380

申请日期：1995.11.04

申请公布日期：1996.08.07

申请人：

KONICA CORPORATION

发明人：YAMAZAKI, HIROYUKU;MATSUMARU, TAKASHI

分类号：G02B13/18;G02B3/04;G11B7/09;G11B7/135;(IPC1-7):G11B7/135

主分类号：G02B13/18

摘要：<p>A device of recording and reproducing on an optical information recording media, includes a light source composed of a semiconductor laser to emit a divergent luminous flux; an objective lens to receive the divergent luminous flux and to converge the diverging luminous flux onto the optical information recording media; and a tracker for tracking a converged luminous flux on the optical information recording media by moving the objective lens in a direction perpendicular to an optical axis. The objective lens has an astigmatism so that a quantity of the astigmatism of a wave-front emitted from the objective lens shows a minimum value at a position where the objective lens is moved away from the optical axis by a tracking operation of the tracker. <IMAGE></p>