| 摘要 |
PURPOSE:To perform adequate diaphragm control with respect to the color difference of an object, by correcting a means which performs the diaphragm control by extracting signals from an image pickup device in accordance with color signal information in the extracted signals. CONSTITUTION:The image of an object is formed at an image pickup element 3 after passing through a lens 1 and its light quantity is controlled by means of a diaphragm 2. The photoelectrically converted output of the element 3 is amplified by an amplifier 4 and color difference signals are separated from part of the amplified output by means of a Y/C separating section 5. The separated color difference signals are synthesized with standard TV signals at a process encoder 6 and outputted to the outside through a terminal 7. The other output S of the amplifier 4 is inputted to diaphragm driving section 10 as signals VS through a gate 9. Part of the color difference signals is inputted to the driving section 10 as correcting signals VC together with gate signals (g) through a correcting signal generator 8 and compared with the mean value of the signals VS. The diaphragm 2 is controlled in accordance with the compared results. The circuit containing the diaphragm 2 and output S forms a feedback loop and maintains the signals VS and VC at the same level. |
