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2. 发明专利

DE3139320A1 Switch-over device for the viewfinder display of a single-lens reflex camera 未知
公开(公告)号：DE3139320A1
公开(公告)日：1982-08-19
申请号：DE3139320
申请日：1981-10-02
申请人： CANON KK
发明人： MOMIYAMA KIKUO , SOMEYA HIROMI
IPC分类号： G03B17/20 , G03B19/12 , G03B13/06
摘要： A description is given of a viewfinder for a single-lens reflex camera, in which information-carrying light is conducted from the vicinity of a pentaprism through the pentaprism, in order to display information images along the field-of-view image. In the space between the pentaprism and the eyepiece there are disposed a subprism with two reflecting surfaces and a reflecting element with one reflecting surface, which is situated opposite the reflecting surfaces of the subprism; in this case, the information-carrying light which enters at the upper, front inclined surface of the pentaprism is directed onto the eyepiece. When the viewfinder has been fitted to the camera body, and when the exposure time wheel has been set to a specified position, the reflecting element is withdrawn from its reflecting position by a control element which is provided in the viewfinder, so that the information image disappears.

4. 发明专利

DE2518457A1 未知
公开(公告)号：DE2518457A1
公开(公告)日：1975-11-13
申请号：DE2518457
申请日：1975-04-25
申请人： CANON KK
发明人： MOMIYAMA KIKUO
IPC分类号： G02B7/10 , G02B13/02
摘要： A telephoto objective comprising a stationary convergent front lens group and a rear lens group which includes a lens member axially movable for focusing behind a front lens member which remains stationary during focusing, and an operating mechanism therefor. In order to achieve excellent stability of the various aberrations and particularly spherical aberration throughout the focusing range, compensation for the residual aberrations introduced by the front lens group is concentrated in the stationary front member of the rear lens group, while the movable rear member is configured to provide minimized variation of aberrations by constructing these two members as being divergent with their front surfaces convex to the object. In this particular arrangement, the movable member is moved toward the image plane as the objective is focused from the position for an object at infinity to the position for a close object.

5. 发明专利

DE2432589A1 未知
公开(公告)号：DE2432589A1
公开(公告)日：1975-01-30
申请号：DE2432589
申请日：1974-07-06
申请人： CANON KK
发明人： MOMIYAMA KIKUO
IPC分类号： G02B9/34
摘要： A photographic objective lens system for adaption with a diaphragm located in front of the entire system. The lens system comprises positive front and rear lenses and a negative intermediate lens in optical alignment with each other. The front lens is in the form of a positive meniscus doublet composed of a double convex lens and double concave lens cemented together at their adjoining surfaces. The intermediate lens is a double concave singlet. The rear lens consists of a positive meniscus front singlet of rearward convexity and a positive meniscus rear singlet of forward convexity. This objective is so designed as to have a relative aperture of at most two in F-number and a field angle as wide as 44 DEG while nevertheless preserving an excellent state of correction of various aberrations.

6. 发明专利

DE3048707A1 未知
公开(公告)号：DE3048707A1
公开(公告)日：1981-09-10
申请号：DE3048707
申请日：1980-12-23
申请人： CANON KK
发明人： YAMADA YASUYUKI , MOMIYAMA KIKUO
IPC分类号： G02B9/34 , G02B9/36 , G02B13/04 , G02B13/18
摘要： The objective disclosed includes, from front to rear, a positive meniscus lens of forward convexity, a negative lens, a positive lens, and a negative meniscus lens having an aspheric front surface concave toward the front, and fulfills the following requirements: -1.5f where f is the focal length of the entire system; fA is the focal length of the air lens defined by the opposing surfaces of the first and second lenses counting from the front; and +TR wherein r7 is the paraxial radius of curvature of the front surface of the 4th lens; and r7* is the radius of curvature of the lens reference spherical surface defined by

7. 发明专利

DE2927478A1 未知
公开(公告)号：DE2927478A1
公开(公告)日：1980-01-24
申请号：DE2927478
申请日：1979-07-06
申请人： CANON KK
发明人： MOMIYAMA KIKUO , KAMATA SHIGERU
IPC分类号： G02B15/16 , G02B15/177 , G02B15/14
摘要： The present invention relates to an objective lens for zooming by varying the distance between the divergent front lens group and the convergent rear lens group consisting of a first sub-group for forming a convergent light beam and a second sub-group between which sub-groups a photographing aperture is provided so as to be independent from them, whereby when the rear lens group is displaced forward for zooming the photographing aperture is displaced backward with reference to the first sub-group.

9. 发明专利

DE2433944A1 未知
公开(公告)号：DE2433944A1
公开(公告)日：1975-02-13
申请号：DE2433944
申请日：1974-07-15
申请人： CANON KK
发明人： MOMIYAMA KIKUO
IPC分类号： G02B13/04 , G02B13/06 , G02B13/18 , G02B9/64
摘要： A retrofocus wide angle objective with the backfocal length being at least two times the overall focal length, comprising in optical alignment, a plurality of negative meniscus lenses of forward convexities, a positive lens, a negative meniscus lens of forward convexity, a bi-convex lens, a negative lens, a positive doublet lens and a positive lens, and the first surface counting from the front being configured in a non-spherical form such that the curvature increases with distance from the optical axis. This non-spherical surface compensates for barrel distortion and negative coma which are introduced by the object-side negative meniscus lenses into the lens system.

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