| 摘要 |
PURPOSE:To make possible rapid and accurate focusing detection by using the evaluation function value which is optimum for either one fousing state of evaluation function values for rough adjustment and fine adjusting, in evaluating the resolution of images. CONSTITUTION:When the image light distribution detection signals constituted by the photoelectric transducer array formed by respectively K pieces of photodetectors provided at a fixed optical distance by way of a plane conjugate with the focal plane of an imaging lens are applied to a CPU 5 via a signal processing circuit, the CPU 5 arithmetically operates evaluation functions S', S for rough adjustment and fine adjustment for every photoelectric transducer arrays based on the formulas I, II. When the function S is above the threshold value, this is used and when it is below the same, the function, S' is used in evaluating the image sharpness and the movement of the lens 2 is controlled by way of an optical system drive control circuit 7 and an optical system drive unit 8. The focusing detection may be performed rapidly, and accurately by the evaluation and adjustment corresponding to the deviation from this focusing position. |
