DE1797197B - Device for displaying an exposure value in the viewfinder of a single-lens reflex camera - Google Patents

Description

Gear 9 is mounted on shaft 11; therefore, when the gear 9 is rotated, the shaft 11 also becomes set in rotation and likewise the spool 3, which is provided at the end of the shaft 11. A thread 2 is wound on the spool 3; the other end of the thread 2 is through the intermediary of a roller 3 'on a Coil 1 wound which "on the opposite Side of the sweeter metal housing 13 is attached. The thread 2 is provided in the bobbin 1 by means of a Spring 15 is constantly tensioned in the direction to the left and is loaded through the gap between the two the two polarizing plates 6 and 7. On the middle section of the thread is a piece of cellophane paper 8 established. This piece of celloohane paper is fixed on the thread by that the thread 2 is passed through two holes; this will make the setting of the layers very simply designed. In the area where the polarization plates aö and 7 overlap, the light cannot reach the observer's eye because the light rays are interrupted; if but the piece of cellophane paper is inserted into the space between the polarizing plates, the interruption of the rays of light is canceled thanks to the optical influence of this piece that the TeU of the light that strikes the piece of cellophane paper 8 through the polarizing plates 7 passes through; this makes the entered number or letter recognizable.

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1 sheet of drawings

Claims (3)

Scale carrier must be provided, the comparative claims: wise takes up a lot of space within the camera. In view of the regularly extremely crowded space 1. Device for displaying an exposure ratio in a camera, this variant is equivalent in the viewfinder to a single-lens reflex lens if it is not particularly suitable. Camera with a pentaprism and a focus object of the invention is to create a device of the sierungsplatte in which a type described for focusing initially, which illuminates the plate adjacent exposure value scale from the light falling into the lens in advantages of the two known devices and combined, but without these two devices being readable through the pentaprism, since - xo having to accept their own disadvantages,
characterized in that two mutually crossed polarization plates (6, 7) are achieved in that two mutually crossed polarization arrangements are provided that they are one plate in such an arrangement that they form dark section , which form the entire be a dark section, which includes the entire exposure value scale, and that comprises 15 exposure value scale to form one, and that for the formation of one the darkened exposure value scale in one the darkened exposure value scale in the range of the set exposure range of the set exposure value lightening zone a plate (8) from opaque zone a plate made of optically active matically active material between the two poles between the two polarization plates (6,7) is arranged, which is arranged (over 20, which is coupled with the camera side 15, 2,3 ', 3, 9, 14, 10) coupled to the camera exposure turning device above the exposure value setting device on the exposure side can be moved over the value index scale.
Exposure value scale is movable. The invention therefore works in principle 2. Device according to claim 1, characterized with a stationary scale carrier, in which the gan * e indicates that the focusing plate (4) on the as scale with the exception of that part, which is the per edge a step (4 ') as a guide rail for the exposure value set because it corresponds through Has plate (8) and a mask is covered over the step (4 '), but this is not easy running, spring-tensioned (1.15) cord pull by mechanical means, but with purely optical means (2) is provided, which is generated with the exposure point means, whereby on the one hand a light direction (over 3.9, 14, 10) coupled movable 30 readability and on the other hand a small space requirement and is attached to the plate (8). are ensured. 3. Device according to claim 1 or 2, since the invention is explained in more detail below characterized in that one of the two becomes polar, in conjunction with execution plates play near the viewfinder eyepiece illustrated in the drawing; in (24) is arranged and also serves as a filter. 35 of the drawing shows Fig.! a side view of the first embodiment in vertical section, F i g. 2 is a perspective view of one of the penta prism and the converging lens according to 40 F i g. 1 part removed, The invention relates to a device F i g. 3 the perspective view of the focus for displaying an exposure value in the viewfinder of a sizing plate according to FIG. 1. single-lens reflex camera with a penta- To the first embodiment according to FIG. 1 prism and a focusing plate, in which one to 3 belong a camera lens 20, a reflex mirror Focus plate adjacent exposure value 45 21, a focus plate 4 with a detached scale illuminated by the light falling into the object level 4 '(Fig. 3), a converging lens 22, a penta and can be read through the pentaprism. prism 23, an eyepiece lens 24 and a glass After a through the German utility model window 25. Documentation 1949 031 known device of the introductory In Fig.2 is a frame 5 for determining the Tend described type appears in the viewfinder 50 part for the display of the exposure information beam path mirrored shutter speed scale un- and the viewfinder image shown; this framework plays below the viewfinder field of view, above the one with which the roller of a washer, to the intermediate shutter speed setting device coupled movable space between the converging lens 22 and the focus pointer is guided. To keep all of the in the finder radiation plate 4 free; at 13 there is a prism joint but delivers observable numerical values to 55 houses. Reason for the comparatively large number of single- The polarization crossing at right angles Would be a rather confusing picture, so that the support plates 6 and 7 are in the upper and lower chose the exposure factor only after carefully looking at the space between which the hen recognized can graze. Step 4 'of the focusing plate 4, the frame 5 To improve the ability to recognize the Bo and the prism or the outer metal housing part the exposure values set in each case, it is also formed. The exposure value marks are knows, always only that of the respective set value on the outside of each of the polarizing plates 6 corresponding scale division within or 7 given; with the wave not shown for a small window in the viewfinder. the shutter speed setting is complete This arrangement - which, in a manner of speaking, engages the kine- 65 a gearwheel 10; when the closure material Reversal of the former is - if each speed is changed, the gear 10 becomes in but the disadvantage of allowing a shift in view of this point of view and twisting it for its part, with misunderstanding after both. Side slidably arranged mulung of the intermediate wheel 14 a gear 9. The