| 摘要 |
PROBLEM TO BE SOLVED: To improve the focusing performance of an electronic camera. SOLUTION: An imaging section 18 periodically outputs a raw image signal expressing an optical image of a field after passing through a focus lens 12. The raw image signal outputted from the imaging section 18 is amplified in an AGC section constituting a CDS/AGC/AD circuit 20. A focus evaluation circuit 20 detects the high frequency component of the amplified raw image signal as a focus evaluation value. A CPU 46 discriminates whether or not the S/N ratio of the raw image signal outputted from the imaging section 18 is excellent. When the discrimination result is positive, the CPU 46 shortens an imaging period and increases the amplification factor of the AGC section. When the discrimination result is negative, the CPU 46 prolongs the imaging period and decreases the amplification factor of the AGC section. After that, the CPU 46 executes focusing based on the focus evaluation value detected by a focus evaluation circuit 30. COPYRIGHT: (C)2009,JPO&INPIT |
