Abstract: A system for automatically adjusting the focus of lens is provided with an auxiliary arrangement for forcibly shifting the lens to a predetermined position when the focus detection by a focus detecting system is either difficult or impossible with the lens being at its initial position and causing the focus detecting system to effect focus detection under the new shifted condition of the lens.

Abstract: In a photoelectric transducer device such as a solid state image pick-up device or sensor having a great number of minute photoelectric transducer elements with their image-receiving surfaces of certain shape arranged in a one-dimensional or two-dimensional manner so that brightness informations of the various individual sections of the object image are sensed by the respective photoelectric transducer elements which then produce outputs in the form of time-sequential signals, the above-described shape of the image-receiving surface area of each of the minute photoelectric transducer elements is made to be such that, as the distance from the center of the image receiving area toward the margin increases, the proportion of the area of a progressively farther concentric zone of the same width is decreased. The shape takes such a form or such characteristics as to be represented by a sampling function or other analogous functions with respect to the scanning direction of the image pick-up device.

Abstract: Disclosed is an image sharpness detecting system in which an image formed by an image forming optical system is received by an array of a plurality of optical-electronic transducer elements, and an illumination difference in each individual minute compartment of the above-described image is detected on the basis of the concurrently obtained output signal from a corresponding one of the optical-electronic transducer elements, while all the illumination differences are summed up over the entire area of a sensing region of the above-described image, whereby is obtained a signal representing the degree of sharpness of the image on the above-described array of optical-electronic transducer elements.

Abstract: Disclosed is a TTL (Through-The-Lens) type focus detecting device for use in an interchangeable lens-equipped camera, in which a plurality of lenslets are positioned at or near the prescribed focal plane of the objective lens, each of the lenslets is associated with two or more pairs of photosensitive elements. Upon attachment of an objective lens to the camera body, one of the pairs of photosensitive elements for each lenslet is automatically selected to operate on the basis of the dimensions of the used objective lens. The outputs of the selected pairs of photosensitive elements for all the lenslets are processed to detect whether or not a positional difference between two images of an object formed with light beams from the objective lens at respective virtual exit pupils lying in almost symmetry with respect to the optical axis thereof is present, whereby the detection of whether or not the objective lens is in-focus is indicated.

Abstract: A focus detecting system for detecting focusing condition of an image forming optical system to an object. In this system there are produced first and second signals corresponding to imaging conditions of object images at first and second positions on front and rear sides of and at substantially equal distances from a predetermined focal plane of said optical system, respectively, and another signal corresponding to imaging condition of an object image at third position substantially coincident with said predetermined focal plane. In accordance with these first, second and third signals, a decision is given as to the focusing condition, namely, in-focus, near-focus or far-focus condition, as well as, the distinction between correctly focused condition and considerably defocused condition.

Abstract: Disclosed is a focus detecting system in which first and second signals corresponding to image forming states at first and second positions each almost at the same distance before and behind a predetermined focal plane of an image forming optical system are obtained. A third signal corresponding to an image forming state at a third position different from the first and the second positions is also obtained. The in-focus state of the image formed by the image forming optical system is detected on the basis of a first comparison signal obtained by comparing the first and the second signals with each other, a second comparison signal obtained by comparing the first and the third signals with each other and a third comparison signal obtained by comparing the second and the third signals with each other.

Abstract: A focal point detection system for detecting the focus adjusting state of an image forming lens during its focusing operation on an object is disclosed. The system comprises a focus detection circuit which produces a detection output that varies with focusing of the lens on the object; a plurality of display elements are provided for display of the focusing state of the lens; and a display control circuit which enables the display elements to display a greater number of focusing states than the number of these display elements through selective combinations of these elements on the basis of the output of the focus detection circuit. The system is capable of displaying intermediate focusing states such as a slightly near-focus state, a slightly far-focus state, and the like in addition to in-focus, near-focus, and far-focus states, so that the focusing state can be displayed stepwise in a detailed manner.

Abstract: The disclosed camera is focused manually with a helicoidally movable lens barrel and fine focused automatically by movement of the lens mount along the lens' optical axis. The lens mount is automatically started at a predetermined position, such as a mid position, in its movable range, and the automatic operation is disabled when the mount reaches either limit of its movable range.

Abstract: In the disclosed TV camera, a focus detecting device detects the focus of the image optical system by evaluating the image of the object whose image is to be picked up, on the basis of the picture image signal obtained at a predetermined position in the image pick up surface of the image pick up device. At least a part of the image to be evaluated is formed at a position within the scanning area of the image pick up device but outside of the effective image pick up area for TV signals. The image is evaluated on the basis of the picture image signal obtained at this position to detect the focus.