초록 ▼

A focus detection system is provided in which an image of an object is projected onto an array comprising a plurality of light acceptor elements, formed by photoelectric elements, to cause them to produce photoelectric signals in accordance with the distribution of light intensity of the image. The

A focus detection system is provided in which an image of an object is projected onto an array comprising a plurality of light acceptor elements, formed by photoelectric elements, to cause them to produce photoelectric signals in accordance with the distribution of light intensity of the image. The photoelectric signals are converted into digital equivalents, and an absolute magnitude of a difference between digital signals of adjacent elements is calculated. These absolute magnitudes are arranged in the sequence of their magnitude, and a given number of them is accumulated, starting from the largest one. The accumulated value is utilized as the value of an evaluation function which indicates the sharpness of the image.

대표청구항 ▼

A focus detection system comprising: (a) focussing means for focussing an image of an object, (b) light acceptor means including K photoelectric transducer elements juxtaposed with each other on a focus plane of the focussing means or on a plane which is optically conjugate with the focus plane, the

A focus detection system comprising: (a) focussing means for focussing an image of an object, (b) light acceptor means including K photoelectric transducer elements juxtaposed with each other on a focus plane of the focussing means or on a plane which is optically conjugate with the focus plane, the light acceptor means producing photoelectric signals whose values vary in accordance with the distribution of light intensity of an image projected thereon by the focussing means, (c) calculating means for calculating the value of an evaluation function which indicates the sharpness of the image based on the signals from the photoelectric transducer elements, (d) the evaluation function being derived by initially obtaining the absolute magnitude of the difference between output signals from adjacent photoelectric transducer elements in the light acceptor means, and accumulating N of such absolute magnitudes which are greatest in their magnitude to provide an accumulated value (where 1≤N≤K-2), the accumulated value representing the value of the evaluation function.