Abstract A focusing detection apparatus comprises an optical system for forming a plurality of images a relative positional relation of which changes in accordance with a focusing state of an object lens, a sensor for producing signals representing the images by detecting the images by a plurality of photo-electric elements, and arithmetic circuitry for determining the focusing state of the object lens based on the signals from the sensor. In order to determine the focusing state, the arithmetic circuitry carries out an operation of ##EQU1## where V is a correlation, a(i) and b(i) are outputs of i-th photoelectric element of the sensor for the respective images, and {x□y} is a constant operational relationship for two real numbers x and y.
Inventors
👤 Kenji Suzuki
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-10-30 12:57
CPC Classifications
G; G02; G02B; G02B7/00; G02B7/28; G02B7/34
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
143 words
A focusing detection apparatus for detecting a focusing state of an object lens, comprising: optical means for forming first and second images a relative positional relation of which changes in accordance with the focusing state of the object lens; first and second sensing means for sensing the first and second images, respectively; and discrimination means for discriminating the focusing state of the object lens in accordance with outputs of said first and second sensing means; said discrimination means calculating a correlation V for discriminating the focusing state of the object lens in accordance with ##EQU6## where N is the number of photo-electric conversion elements of said first or second sensing means, a(i) and b(i) are outputs of i-th photo-electric conversion elements of said first and second sensing means, respectively, and {x□y} is a constant operational relation for two real numbers x and y.
Claim 2
Dependent Claim
143 words
A focusing detection apparatus for detecting a focusing state of an object lens, comprising: optical means for forming first and second images a relative positional relation of which changes in accordance with the focusing state of the object lens; first and second sensing means for sensing the first and second images, respectively; and discrimination means for discriminating the focusing state of the object lens in accordance with outputs of said first and second sensing means; said discrimination means calculating a correlation V for discriminating the focusing state of the object lens in accordance with ##EQU6## where N is the number of photo-electric conversion elements of said first or second sensing means, a(i) and b(i) are outputs of i-th photo-electric conversion elements of said first and second sensing means, respectively, and {x□y} is a constant operational relation for two real numbers x and y.
Claim 3
Dependent Claim
21 words
A focusing detection apparatus according to claim 1 wherein {x□y} is one of |x-y|, {max x, y} and {min x, y}.