Regenerating device for optical recording medium in which overlapping regions are read out by a light beam in a time sharing manner to provide servo control of the positional relationship between the light beam and the medium

A regenerating device for an optical recording medium comprising:

• light beam application means for applying a light beam from a light source on an optical recording medium;
• a detector in which a reflection light from said optical recording medium is applied as an incident light for said detector to convert photoelectrically said incident light so as t obtain detecting signals, said detector configuring an image sensor by including cell groups disposed in a matrix configuration, readout switches, column selecting means for selecting said readout switches provided at every column on the basis of inputted column-address information, and row selecting means for selecting cells in a specific row on the basis of inputted row-address information;
• row-address generating means for generating row addresses and outputting information of said row address to said image sensor;
• column-address generating circuit means for generating column addresses and outputting information of said column address to said image sensor;
• readout means for defining, by time sharing, a cell region in a predetermined position of all of said cells disposed in said image sensor so as to execute time-sharing read-out of charges, which is stored in said cells, as a detecting signal;
• servo control means for controlling a positional relationship of the light beam from said light source to said optical recording medium by processing one portion of said time-sharing detecting signals which are read out from said cells of said image sensor by said readout means;
• and
• reading means for reading information recorded on said optical recording medium by processing another portion of said time-sharing detecting signals which are read out from said cells of said image sensor by said readout means,
• wherein at least two cell regions, in a plurality of cell regions of said image sensor defied by said readout means, are overlapped to share a common region, and, wherein said servo control means processes said time-sharing signals obtained from cells included in said two cell regions and controls an optical head.