US 6,185,044 B2 · TV lens with still-taking function

Abstract

In a still-image-capturing system, a still-image-capturing lens group having totally the same configuration (the same number of lens sheets, lens form, and lens material) as the lens group used only for a TV-image-capturing system is disposed downstream a half mirror, and a rectangular prism is disposed for providing a luminous flux with an optical path length identical to that within a color-decomposing prism when the luminous flux passes therethrough. In another aspect, a focal length conversion lens group for changing the focal length of zoom lens groups and a total reflection mirror is disposed on the optical axis of the zoom lens groups exclusively from each other. In still another aspect, an electronic still camera is attached to the still-image-capturing system. If the size of each of image-capturing devices in the TV-image-capturing system is the same as that of the image-capturing device of the electronic still camera, letting the focal length of the fifth lens group be fA, the focal length of the taking lens of the electronic still camera be fB, and the converter magnification of the converter lens be MC, the converter lens satisfying the expression of fA=MC·fB can make the angles of views of the TV-image-capturing and still-image-capturing systems coincide with each other. In still another aspect, a mechanical shutter is disposed between the half mirror and the still-image-capturing lens group, such as to be opened only during the charge storage period of the first field in response to an image readout operation for one frame.

Claims20

Dependent claims

A TV lens equipped with a still-taking function having a plurality of lens groups attached to a front end of a TV camera main body mounted with a color-decomposing prism for decomposing, in terms of color, a luminous flux carrying object image information, said TV lens comprising:

a reflecting mirror, disposed at a predetermined inter-lens position in said plurality of lens groups, for guiding said luminous flux carrying object image information into a direction different from said TV camera main body;
and a still-image-capturing device, irradiated with said luminous flux guided by said reflecting mirror into said direction different from said TV camera main body, for capturing a still image of said object image;
wherein, between said reflecting mirror and said still-image-capturing device, a still-image lens section formed into the same shape from the same material as a lens section positioned downstream said reflecting mirror, and an optical block for yielding, for a luminous flux incident on said still-image-capturing device, an optical path length substantially equivalent to an optical path length of said luminous flux incident on said color-decomposing prism within said prism are disposed.

A TV camera equipped with a still-taking function having a plurality of lens groups attached to a front end of a TV camera main body mounted with a color-decomposing prism for decomposing, in terms of color, a luminous flux carrying object image information, said TV lens comprising:

a reflecting mirror, disposed at a predetermined inter-lens position where said luminous flux is substantially a parallel luminous flux in said plurality of lens groups, for guiding said luminous flux into a direction different from said TV camera main body;
and
a converter lens disposed between an electronic still camera and said reflecting mirror, said still camera having a relative position secured with respect to said plurality of lens groups and being adapted to take in said luminous flux guided by said reflecting mirror into said direction different from said TV camera main body so as to capture a still image of said object image, said converter lens being adapted to adjust a focal length of an optical system of a still-image-capturing system such that, according to a difference in focal length between a taking lens of said electronic still camera and a lens disposed downstream said reflecting mirror in said plurality of lens groups and a difference in image-capturing size between an image-capturing device disposed within said TV camera main body and an image-capturing device disposed within said electronic still camera, angles of view in said two image-capturing devices are substantially equivalent to each other.

Dependencies are inferred from the claim text.

TV lens with still-taking function

Life of this patent

TV lens with still-taking function

Life of this patent

Abstract

Claims20