Minolta Camera Kabushiki Kaisha

Minolta Company, Ltd.

Minolta Camera Co., Ltd.

Hisashi Tokumaru

Tokuji Ishida

Nobuyuki Taniguchi

Hisayuki Masumoto

Hiromu Mukai

Takanobu Omaki

Masaaki Nakai

Tsuneyo Metabi

Toshihiko Karasaki

Hiroshi Ootsuka

Masayuki Ueyama

Akiyoshi Nakamura

Minoru Kuwana

Shuji Ogino

Yasuaki Serita

Kenji Ishibashi

Takashi Okada

Junji Hashimura

Akira Fukushima

Yukio Maekawa

Tetsuya Arimoto

Hiromu Umeda

Kohtaro Hayashi

Yasumasa Sawai

Takehiro Katoh

Mitsuo Yasukuni

Nobuo Mushiake

Mitsuko Date

An illumination optical system has a lens array for dividing light from a light source into a plurality of beams of light; a polarized light conversion optical system having a separator and converter, wherein the separator has a prism array comprising a plurality of right angle prisms arranged consecutively with the same surface being an inclined surface for reflecting the plurality of beams of light by the inclined surface and separating the plurality of reflected beams of light into first and second linearly polarized light beams having mutually intersecting polarization directions, and the converter converts the polarization direction of one of the first and second linearly polarized light beams to the ot her polarization direction, wherein the lens cell width of the lens array is greater than the prism array pitch of the prism array viewed from the incidence side of the plurality of beams of light.

Illumination optical system and projector using same

A camera in which the ratio of an object to the photographing frame can be set comprises a varifocal lens in which the in-focus position is changed in accordance with the change in the focal lens and a focusing lens for correcting the focus by the varifocal lens. The size of the object is set to the desired size by using the varifocal lens, and thereafter the deviation of the in-focus point is controlled by the focusing lens. Since the zooming is carried out by using a varifocal lens, a camera can be provided in which the ratio of an object to the photographing frame can be set in a simple structure.

Camera having a varifocal lens

A camera having a lens, whereby a power source in the camera is activated in response to a mechanical switch on the lens.

A camera system comprises an operation member provided in an interchangeable lens adapted to be manually operated; a signal sending circuit for sending a signal in response to the manual operation of the operation member; and a controller provided in a camera body which is adapted to switch between an operative state where a predetermined operation is executed and a halt state where the controller is halted after completion of the predetermined operation. The controller switches from the halt state to the operative state in response to the signal from the signal sending circuit to execute the predetermined operation. According to the camera system, since the system controller in the camera body is actuated in response to the operation of the member on the lens side, a camera which can substantially instantaneously respond to a request on the lens side can be realized.

Camera system with zoom lens having presettable focal lengths

A new compact-size, light-weight and low-cost zoom lens system having a high optical quality with a very simple structure including, from the object side to the image side, a front lens group having a positive refractive power and a rear lens group having a negative refractive power. The zoom lens system is operated by changing the axial air distance between the front and rear lens groups during a zooming operation. The zoom lens system uses aspherical surfaces whose low-cost manufacturing has been enabled by the recent progresses in plastic molding technology and glass molding technology. Many embodiments of the lens compositions according to the present invention, and further more specific examples of the embodiments are described with figures and data that show compactness and high optical performance.

Compact size zoom lens system

The present invention discloses a camera having power zooming function to execute zooming by electric power in accordance with manual operation and power focusing function to execute focusing by electric power in accordance with manual operation, in which both the power zooming and power focusing can be executed by one operation member. The operation member can be rotated and moved back and forth, and can execute power zooming responding to its rotation and power focusing responding to its movement back and forth.

Camera with multiple lens driving modes

A camera system comprises an operation member provided in an interchangeable lens adapted to be manually operated; signal sending circuit for sending a signal in response to the manual operation of the operation member; and a controller provided in a camera body which is adapted to switch between an operative state where a predetermined operation is executed and a halt state where the controller is halted after completion of the predetermined operation. The controller switches from the halt state to the operative state in response to the signal from the signal sending circuit to execute the predetermined operation. According to the camera system, since the system controller in the camera body is actuated in response to the operation of the operation member on the lens side, a camera which can substantially instantaneously respond to a request on the lens side can be realized.

Camera system which compensates for defocusing during operation

A camera which has a photo-taking lens capable of zooming, and a viewfinder which shows a first photographing range and a display which displays one frame defining a second photographing range smaller than the first photographing range, wherein out of photographing range showing mode is provided. And when the out of photographing range mode is selected, after zooming operation is carried out, the second photographing range is exposed on a film, whereby the visual field in the finder can be enlarged and, provided that a camera has a focus detector, the focus detecting area can be relatively enlarged.

Viewfinder framing device for zoom lens camera

A compact-size, light-weight, low-cost zoom lens system with high optical quality is achieved by using a ray restrictor placed at the most object side of the zoom lens system. In one type, the ray resistor shifts toward the object at a speed different from that of the most object side lens of the zoom lens system as the zoom lens system is zoomed toward the longest focal length, which effectively blocks harmful rays causing coma flare in the peripheral area. In another type, the aperture diameter of the ray restrictor varies according to a zooming operation. The ray restrictor of any type is especially effective when used in a zoom lens system composed of two lens groups. By introducing one or more aspherical surfaces satisfying a certain condition (or conditions) in the zoom lens system, various aberrations are further favorably corrected.

Compact-size zoom lens system

In a zoom camera having a zoom lens including a variator lens, and a driving system for driving the variator lens, the image magnification is computed in accordance with a predetermined program based on the detected object distance, and such a focal length is computed as to obtain a specified value of image magnification based on the detected object distance and the computed image magnification, and the obtained focal length data is fed to the driving system. As a result, auto-zooming with a suitable image magnification in accordance with the object distance can be achieved.

Zoom camera

A compact size zoom lens system ranging to a wide field angle and having a high zoom ratio of up to 10. The zone lens system is composed of, from the object to the image side, a positive first lens group, a negative second lens group, a positive third lens group and a negative fourth lens group, and fulfills the following conditions:

Zoom lens system having high zoom ratio ranging to wide field angle

A focus condition detecting device which eliminates a wasteful operation thereof to obtain optical results of detection in a shortest period of time and wherein it can be discriminated correctly depending upon data read from a lens regarding an exit pupil of the lens whether or not detection of a focus condition is possible. The device comprises an optical means which forms a plurality of pairs of light images from beams of light from pairs of areas of an exit pupil plane of an interchangeable lens. Relative displacements between the light images are detected by a plurality of focus condition detecting means. Data regarding optical characteristics of the lens are read from the lens, and in accordance with the data thus read, those ones of the focus condition detecting means for which detection of a focus condition is possible are selected from an optical relationship between the optical means and the exit pupil of the lens. An in-focus condition is finally determined from focus condition signals produced from the selected focus condition detecting means.

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Osaka, Japan

Hisashi Tokumaru