Automatic focusing camera

Abstract

An automatic focusing camera comprises a measuring device formed integrally with a camera housing, defining a distance measuring zone selectively extended in different directions, and adapted for producing information employed for focusing to an object contained in the extended distance measuring zone. A position detecting device for detecting the position of the camera housing, and a device for varying the extending direction of the distance measuring zone, in response to the position of the camera housing detected by the position detecting device.

Description

BACKGROUND OF THE INVENTION1. Field of the InventionThe present invention relates to an automatic focusing camera which controls focusing by producing plural information for focus adjustment from the object field.2. Related Background ArtIn conventional automatic focusing cameras, the information for focus adjustment (distance measuring information or defocus information) is produced by projecting light from a light-emitting unit to an object positioned in the center of the object field determined by the view finder and receiving the light reflected from said object, but, there cannot be obtained information for focus adjustment, in case of photographing with an image frame composition with the main object not positioned in the center, thus resulting in a so-called central defocus picture.In order to prevent failure in the control resulting from such central defocus, there is already realized a so-called multi-focus camera in which plural light-emitting elements are provided for pro...

AI Technical Summary

Benefits of technology

An object of the present invention is to provide an automatic focusing camera capable of reliably preventing such central defocus phenomenon with simple structure and processing, even when the camera position is changed.

In such automatic focusing camera of the present invention, certain measuring points are selected to prevent the central defocus phenomenon according to the change in the camera position, so that appropriate automatic focusing can be achieved without such phenomenon, regardless of the camera position.

Also the number of the measuring points is maintained at a minimum necessary value, whereby the discrimination process for focusing control can be simplified.

Problems solved by technology

In conventional automatic focusing cameras, the information for focus adjustment (distance measuring information or defocus information) is produced by projecting light from a light-emitting unit to an object positioned in the center of the object field determined by the view finder and receiving the light reflected from said object, but, there cannot be obtained information for focus adjustment, in case of photographing with an image frame composition with the main object not positioned in the center, thus resulting in a so-called central defocus picture.

However, such camera designed to produce plural information for focus adjustment from the object field may still result in such central defocus if the position of the camera is moved, since the plural light-emitting elements are arranged on the assumption that the position of the camera is constant at the photographing operation.

However, the use of such many light-emitting elements requires complex processing for selecting the information finally used in focusing control from many focus adjusting information from said light-emitting elements, thus resulting in an elevated cost due to a complex circuit structure if said processing is achieved by hardware, or a longer time required for such selection if said processing is achieved by software.

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