CN88211094U

CN88211094U - Viewfinding and zooming combined photographic lens

Info

Publication number: CN88211094U
Application number: CN 88211094
Authority: CN
Inventors: 王树森
Original assignee: Individual
Current assignee: Individual
Priority date: 1988-02-11
Filing date: 1988-02-11
Publication date: 1988-08-17

Abstract

The utility model relates to a view-finding and zooming combined photographic lens for a low-grade camera with a fixed object lens. The view-finding and zooming combined photographic lens can be installed and used on any low-grade cameras by means of a connecting seat, having the similar effect of the viewfinder of the single reflex camera, and finding a view through a zooming object lens; the manufacturing cost of the small scale production is only a plurality of tens of yuan. The photographic lens has novel shape and simple structure, and is suitable for the bulk production of the large, medium and small-scale optical factories. The novel product having the function of the low-grade camera fills the blank that the domestic and foreign low-grade camera have the zooming function, having huge market demand and broad prospect, and the photographic lens is a competitive product for exchanging the foreign exchange.

Description

Viewfinding and zooming combined photographic lens

The utility model is about the invention of camera with varifocal photography cover mirror, the invention of particularly find a view, mirror is overlapped in the varifocal photography.

The domestic and international camera in modern age is of a great variety, yet puts it briefly, and can be divided into two big classes.The low-grade camera of first fixture mirror, it two is the middle and high shelves of the interchangeable single lens reflex type of object lens cameras.Low-grade camera market demand maximum because the object lens on the camera are fixed, can not be changed, so, aspect functions of use, also just be very restricted.For example take that the people resembles, potted landscape, flowers, bird, object and reproduction data or the like, low-grade camera is just powerless, this is that vast shutterbugs wish the big problem that can solve in the future.Regrettably not only there is not a kind of objective with variable focal length can give low-grade camera configuration on the domestic and international market, very cause the narrow angular magnification mirror that comes out already, also squeezed, on the market " disappearance " because of the too low production of price by the objective with variable focal length of middle and high shelves slr camera.Present technology and production status can not adapt to the contemporary market demand far away, and this shows in the camera industry and is breeding a kind of new competition and the exploitation of new varieties.

Task of the present utility model is the accessory that a kind of expanded function is provided for the low-grade camera of fixed object lens---finds a view, varifocal photography cover mirror, makes low-grade camera have the purpose of the general common function of middle and high shelves slr camera to reach.

Invention main points of the present utility model are: the scientific payoffs that the kinematograph objective with variable focal length is had concurrently a viewfinder function is used for the improvement of low-grade camera, replace original complicated varifocal photographic field lens with varifocal cover mirror simple in structure, replace original Amici prism system with 45 ° of deflection angle plane mirrors, replace the very long view finder of external form that has the erect lens group on the original video camera with the short and small counter-rotating Galileo type view finder or the road prestige erecting prism formula view finder that are suitable for camera.Accompanying drawing 1 is exactly an embodiment synoptic diagram of the present utility model to accompanying drawing 3, and the miniaturization structure that is primarily characterized in that view finder is arranged on varifocal cover mirror and fixedly between the object lens.

Accompanying drawing 1 is the Amici prism formula varifocal photography cover lens device of finding a view.Between the varifocal cover mirror (1) of fixedly object lens (0) and burnt pattern far away, set up a component light prism group (2), its reflectivity is about 20% light beam by reversing Galilean telescope formula viewing lens (3), reflective mirror (4) and eyepiece (8) afterwards, becomes out the amplification virtual image to inject eye pupil (9); Transmissivity is about 80% light beam by prism (2) and fixed object lens (0) imaging on the plane of film gate (10) in addition.Because the focal length of viewing lens is a negative value, in order to make find a view picture and sheet gate open light area proportional, first lens light hole of varifocal photography cover mirror changes into square, aspect ratio is 2 to 3, exposure when this will make long burnt position open sufficient aperture photography descends, and this shortcoming is because the too simple consequence of viewfinder structure; In addition,, make that the brightness of view finder is very low, when indoor photograph, just seemed inconvenient owing to also keeping the kinematograph objective with variable focal length beam splitting prism attachment of finding a view.

Accompanying drawing 2 is improvement projects of the present utility model.Be to replace Amici prism (2) with 45 ° of deflection plane reflective mirrors (2E), make the beam brightness of view finder increase about three times, even in indoor photograph, the visibility of the image of finding a view remains quite high; The structural shape of varifocal photography cover mirror is selected easy to use along the plug-type optical compensation structure of optical axis; In order to make find a view effect and slr camera approaching, the focal length of viewing lens (3) choose on the occasion of, folded light beam becomes out resembling of coloured limit and distortion by viewing lens (3), fixed plane mirror (4) at field stop (5), proofread and correct by field lens (6) again, to satisfy cheap economic target; Short and small and ridge Dove prism (7) is set replaces the erect lens group in order to adapt to camera thickness, eyepiece (8) also is a single element lens, and its outgoing beam becomes out the virtual image on the distance of distinct vision to inject eye pupil (9).45 deflection plane reflective mirrors (2E) are arranged in the rotating shaft (C), on the camera shutter start button, adorn an antinous release, be connected varifocal and overlap (mechanical component this as that extensively known need not to draw) on the sync cap of mirror on synoptic diagram, when starting shutter, the bar that the core pin of antinous release promotes rotating shaft (C) makes dotted line position that 45 ° of plane mirrors (2E) forward (2P) in a flash, and shutter opening makes the egative film exposure; Finger leaves after the button, and rotating shaft (C) is subjected to the pressure of torque spring that plane mirror is resetted to locate in the position of finding a view (2E): this is a kind of simple synchronous device.Antinous release can be bought in that photographic material is capable, the antinous release interface of varifocal photography cover mirror also is better simply mechanical component, be easy to design and manufacturing, so the batch manufacturing cost of this programme is very low, except that the optical element of varifocal cover mirror is still needed by the cold working realization, other optical elements all can be considered to annotate compacting now with organic glass, plane mirror (4) and (2E) can aluminize with the float glass plate surface and realize, other metal construction element can adopt ABS black plastic notes to be pressed into shape and realize.

Accompanying drawing 3 is that the utility model is contained in the synoptic diagram on the low-grade camera of fixed object lens.Find a view, the Connection Block (11) of varifocal photography cover mirror (2F) by having location-plate (D), be fastened on the camera crane nut, below it, also have the screw of a same specification to connect and use to tripod with fastening screw dish (12).Location-plate is a dovetail groove device, can make that varifocal photography cover mirror is left and right to be moved until with till fixedly object lens align, and tightens gib screw (14); Connection Block (11) and utility model application number are that the coupling arrangement of 87209934 " the unit coordination is stereoscopic photograph cover mirror in the same way " is general.This coupling arrangement can be pressed into shape with ABS black plastic notes fully and realize.

The utility model has been filled out the infull blank that causes of domestic and international low-grade camera function, and it is novel that it installs, and simple in structure, cost only has tens of units, is fit to the batch production of large, medium and small type optics factory; Can also increase a large amount of foreign exchange earnings to China in addition.

Claims

1, a kind ofly find a view, varifocal photography cover mirror, it is characterized in that: the Amici prism [2] that the usefulness of finding a view is housed between varifocal photography cover mirror [1] and fixed object lens [O]; The structural shape of view finder is the device of counter-rotating Galilean telescope formula.

2, according to claim 1ly find a view, varifocal photography cover mirror, it is characterized in that: between varifocal photography cover mirror (1) and fixed object lens (0), 45 deflection angle plane mirrors (2E) are set, folded light beam is located imaging by viewing lens (3), fixing 45 plane mirrors (4) at field stop (5), becomes out the device of amplification virtual image then again with eyepiece (8) by field lens (6) and ridge Dove prism.

3, according to claim 1 and 2 described devices, it is characterized in that: 45 deflection angle plane mirrors (2E) are contained in the rotating shaft (C), in the camera exposure in a flash, 45 deflection angle plane mirrors (2E) forward the position of (2P) to, and this is the synchronous device that is connected the flexible cord interlock by shutter.

4, according to claim 1,2,3 described devices, it is characterized in that: the device that find a view, varifocal photography cover mirror (ZF) can be connected with any 135 low-grade cameras by Connection Block (11).