| 摘要 |
PURPOSE:To realize the recording and reproduction of large capacity information with a miniature constitution and without using any special advancing mechanism for an optical disk device, by starting the tracking control after shifting an objective lens, etc. in the radius direction by a desired extent. CONSTITUTION:A holder 42 of a magnetic body which holds an objective lens 41 is supported by an intermediate frame 45 connected with an outer frame 48 by spiral springs 46 and 47 and via plate springs 43 and 44. In addition, permanent magnets 49 and 50 are fixed to the frame 48 together with yokes 53 and 54 wound by driving coils 51 and 52. The supporter 42 has displacement in response to the control of the driving current for coils 51 and 52. Then the tracking of the lens 4 is controlled without using a large-sized advancing mechanism which had a minute shift in the direction rectangular to a track. As a result, it is possible to record and reproduce the large capacity information which received good tracking with a miniature constitution and without using any special advancing mechanism after an objective lens, etc. is shifted in the radius direction of an optical disk by an extent equivalent to a desired number of tracks. |
