An automatic focus detection system for use in a camera system comprises focus detecting unit having one light receiving element corresponding to, in an objective field, a focus detection area whose center is deviated from the optical axis of the objective lens, the position of the focus detection area being changed in accordance with the change of the focal length of the objective lens; and a light projecting unit for projecting light towards the object field so that the region of the projected light covers the focus detection area, if the position of the focus detection area is changed in accordance with the change of the focal length of the objective lens.

Automatic focus detection system

A focus detecting apparatus, characterized in that it comprises, multiple detecting zones situated in a focal plane, an orientation changing mechanism which changes the orientations of images formed in these zones, an image separating device which separate these images into image pairs, and multiple sensors, having a different positional relationship to that of the multiple detecting zones, which detect the image pairs.

Focus detection apparatus having multiple detecting zones

An automatic focusing apparatus for use with a camera of the type having two interchangeable lenses with different focal lengths, includes a ranging device for finding in which distance range is located an object to be photographed, i.e., close range or long range. The ranging device is capable of shifting the position of the boundary between short range and long range when interchanging lenses in order to widen the limits of the range in which either of the lenses can be focused better.

Automatic focusing apparatus

An automatic range finding device has a light-emitting unit for emitting a slit of light as a beam toward a subject and a light-receiving unit for receiving light reflected from the subject, thereby to detect the subject distance based on the incident position of the reflected light received by the light-receiving unit. The light-emitting unit emits the slit of light slantwise relative to the image plane.

Automatic range finding device

Disclosed is a focusing lens position detection apparatus provided in an auto-focus surveying instrument that includes a telescopic optical system having a focusing lens which moves along an optical axis, a beam splitter which splits object light transmitted through the focusing lens to produce light split from the telescopic optical system, and a focus detector which receives the split light from the beam splitter. The focusing lens position detection apparatus includes: an indicia member provided on the focusing lens, which is located outside the light path of the telescopic optical system; and a light path changing member provided between the beam splitter and the focus detector, which is movable between a first position in which the split beam from the beam splitter can be received by the focus detector and a second position; wherein the light from the indicia member can be received by the focus detector.

Focusing lens position detection apparatus and an auto-focus surveying apparatus

In an automatic focusing camera comprising optical object distance detecting means having a light emitting element for measuring an object distance and a light receiving element for receiving the reflected light from an object, provision being made of rotating means which rotates about an optical axis of a camera lens and which has scanning means cooperating with the light receiving element to detect the object distance as a function of an angular displacement of the rotating means.

Hiroshi Kimata

Papers

Automatic focusing camera