Abstract: There is provided an image pickup apparatus with zooming function, which is equipped with a photoelectric converter for converting an image of an object to be taken by an optical system into an electric signal. The optical system and photoelectric converter are provided as separately slidable on an optical axis. A high frequency component of the electric signal is extracted to determine if the image is in focus by means of level of the high frequency component. Responding to the result of the judgement, the optical system and photoelectric converter are respectively slid to click stop points on the optical axis where the image is in focus.

Abstract: An automatic focusing apparatus having a focusing lens system and an image pickup device for converting a light beam incident thereon into the corresponding electrical signal. The automatic focusing apparatus is arranged so that focusing is performed in accordance with the focus voltage obtained from a predetermined high-frequency component of the electrical signal, on the basis of the fact that the level of the focus voltage corresponds to the sharpness of the resultant image. The focus voltage is successively compared with each of a plurality of reference voltages predetermined to be increased in steps. The focusing lens system is controlled in position in accordance with a comparison between the first reference voltage agreeing with one of the focus voltages and the second reference voltage agreeing with another focus voltage so that the focusing lens system approaches the focus position.

Abstract: An optical zooming system comprising a zoom lens device for varying the focal length of the zooming system by its own movement in directions of the optical axis thereof and a cylindrical cam device arranged to encase the zoom lens. The zoom lens device has an engaging pin at its peripheral surface which is engaged with a cam groove formed at the inner circumferential surface of the cylindrical cam device to be movable along the cam groove. The cylindrical cam device is coupled to a drive device to be rotated so that the zoom lens device is moved in the optical axis directions in response to the rotation of the cylindrical cam device. The cam groove has a configuration formed so that the focal length of the zooming system is varied in linear relationship to the angle of rotation of the cylindrical cam device.

Abstract: An optical low-pass filter is used in a television camera which has an optical system including an iris and a color stripe filter. The optical low-pass filter comprises a base plate, and a plurality of bi-prisms respectively formed on at least one surface of the base plate, and extending parallel with respect to one direction, where the plurality of bi-prisms are arranged at a pitch which is smaller than the diameter of a minimum aperture used of the iris.

Abstract: A television camera has an optical system including an iris, a master lens, and a color stripe filter. The television camera further comprises an optical lowpass filter provided within an effective light path of an afocal system which reaches the master lens through the iris. The optical lowpass filter has a shape to partially produce an optical lowpass filter effect with respect to a part of a beam in the effective light path.

Abstract: A single-lens reflex type viewfinder as for VTR cameras has a prism for deflecting a portion of light coming through a main camera lens along a first optical axis to pass through a viewfinder master lens along a second optical axis normal to the first optical axis, and a mirror for reflecting the deflected light portion toward a viewfinder eyepiece along a third optical axis normal to the second optical axis and parallel to the first optical axis. The mirror is disposed on an image formation point of the viewfinder master lens to keep viewfinder and picked-up camera images in agreement with each other and hence to eliminate viewfinder adjustment. To remove any deviation of the viewfinder image from the third optical axis and eliminate any inclination of the viewfinder image, the mirror and/or prism is angularly movable about the first axis, the second axis, and/or the third axis.

Abstract: A simplified type television camera includes an optical system comprising a main lens system, a camera (pickup) tube, and an optical viewfinder. The television camera comprises a single frame consisting of a pair of half frames respectively having opposing contact surfaces contacting with each other along a surface including an optical axis of the optical system, and holding parts for holding said optical system in a state where the pair of half frames are combined with the contact surfaces contacted.