| 摘要 |
PURPOSE:To improve the AF accuracy of a camera, by previously storing discrepancies in sensitivity between photoelectric transducers elements in the main body of the camera as coefficients of correction and equivalently eliminating the sensitivity discrepancies between the elements by using the coefficients of correction. CONSTITUTION:When a CPU 22 for AF sends an integration start signal to a focus sensor 20, the sensor 20 performs photoelectric conversion and accumulates electric charges in accordance with the contrast of an object. An A/D converter 21 successively A/D-converts the electric charges of the sensor 20 and transfers the converted data to the CPU 22 for AF. The data transferred to the CPU 22 are stored in a RAM. When the input of the sensor data is completed, the coefficient of correction of the sensor 20 is read from a main body data circuit 30 through a main CPU 14. Then the phase difference of the distribution of intensity of illumination is counted by increasing the value of the shifting quantity one by one. When the phase difference is calculated, the coefficient of correction stored in the RAM of the CPU 22 is read out and calculation is performed so as to correct the sensitivity discrepancy between the photoelectric transducers constituting the sensor 20. |
