| 摘要 |
PURPOSE:To provide a photometric unit for camera in which current consumption is restricted while maintaining a high photometric upper limit. CONSTITUTION:A microprocessor 12 receives a first clock and a second clock having lower frequency externally and select one of them as its own operational clock. A clock having frequency proportional to that of the operational clock is then delivered from the microprocessor 12 to a CCD 13. In synchronism with that clock, the CCD 13 converts the optical intensity of a light from a scene into an electric signal which is delivered to the microprocessor 12. The microprocessor 12 performs photometric operation and exposure control based on the electric signal. The microprocessor 12 selects the first or second clock depending on at least one of the focal distance of a pickup lens, the aperture stop value and a previous photometric value. |
