| 摘要 |
PURPOSE:To shorten automatic focus adjusting time by finding out the positional shift value of an object image from a focusing position on a light receiving part surface from data obtained from a focus detecting light receiving part and calculating the defocus value of a lens from the shift value and fixed data based on a specific formula. CONSTITUTION:The titled device is provided with the focus detecting light receiving part 11 and an arithmetic means 11, the shift value delta of the object image from the focusing position on the surface of the light receiving part 11 is found out from the data obtained from the light receiving part 11 by the arithmetic means 11 and the defocus value DELTA of the lens is found out from the shift value delta and the fixed data A1, A2 on the basis of operation DELTA=A2/(delta+A1)-A2/A1. Thus, the automatic focus adjusting time can be shortened with high range finding accuracy even if the defocus value is large. |
