SOLID-STATE IMAGE-PICKUP DEVICE, AUTOMATIC FOCUS ADJUSTMENT DEVICE USING IT, AND IMAGE-PICKUP SYSTEM

摘要

PROBLEM TO BE SOLVED: To improve the transfer efficiency of a signal charge and to reduce cost by providing a substractor section between a horizontal CCD and a circulation CCD, subtracting a signal charge at a non-lighting from a signal charge at lighting and transferring the difference to the circulation CCD sequentially, so as to be accumulated therein. ;SOLUTION: For a solid-state image pickup device, a substractor section 60 is provided between a horizontal CCD 140 and a circulation CCD 70. A signal charge transferred to the horizontal CCD 140 is transferred to a substractor section 6, placed at a pre-stage of the circulation CCD 70. The substractor section 60 subtracts the signal charge at non-lighting from the signal charge at lighting and transfers sequentially only the signal charge after the subtraction processing to the CCD 70. The transferred signal charge only after the subtraction processing is circulated in the circulation CCD 70 and summed with a signal charge after succeeding subtraction transferred from the substractor section 60 for every circulation. The signal charge is amplified by repeating the operation and when the charges amount to a prescribed amount, the charges are transferred to a read section, in which a focus with respect to an object is specified.;COPYRIGHT: (C)1998,JPO