| 摘要 |
PURPOSE:To detect a focus with high accuracy even if an image of an object to be photographed contains a lot of high space frequencies, by placing a lenslet array on the surface spaced at a distance in the opptical axis direction from a surface conjugate to a film suface. CONSTITUTION:When a photographic lens is in a focused state with respect to a surface 2 conjugate to a film surface, 2 images of an object to be photographed, which pass through 2 areas of an exist pupil and are formed at a lenslet array position 10 become out of focus and simultaneously generate its deviation. Accordingly, an output signal of a photoelectric element array group A and an output signal of a photoelectric element array group B generate a phase difference phi0. The focusing state can be discriminated by detecting a phase difference phi in accordance with a rear pin state and a front pin state, and deriving phi'=phi-phi0. |
