JPS6169043A - Photometric device of camera - Google Patents

Abstract

PURPOSE:To prevent an optical system of a camera from being darkened by a transparent electrode, by extending linearly a photoelectric transducer for photometry and forming transparent electrodes, between which the photoelectric transducer is interposed, to the same shape as the photoelectric transducer. CONSTITUTION:A lower electrode 28 consisting of a transparent conductive film is arranged in a comb teeth pattern on a transparent glass substrate 27, and a photoelectric transducer 29 and an upper electrode 30 having the same pattern shapes as the electrode 28 are laminated on the electrode 28. Lead wires 31 and 32 are connected to end parts of electrodes 28 and 30. Since a width (d) of a photoelectric transducer body 26 constituted in this manner is several mum or smaller, it is impossible to discriminate this body 26 with naked eyes, and the body 26 has no influences upon the field of view of the finder of the camera. Thus, the optical system of the camera is prevented from being darkened in comparison with the method where a transparent electrode is provided on the whole of a light-transmissive face.

Description

[Detailed description of the invention] The present invention relates to a photometry device for a camera.

Conventionally, photometric devices for -eye reflex cameras have either guided a light beam to a photometric element using a light splitting member such as a microheam sliver formed on a condenser lens, or have used a Fresnel lens provided on the light output surface of a pentaprism. Although some proposals have been made for converging light through a lens, they have drawbacks such as obstructing the light intensity distribution in the viewfinder field of view or requiring replacement of the light splitting member when changing the photometry method.

1 and 2 show an example of a conventional photometry device, and FIG. 1 is a sectional view of the optical system of a single-lens reflex camera. Here, the subject light that has passed through the photographic lens 1 is reflected in one direction by the reflex mirror 2, and is then reflected by the focusing plate 3, the light splitting member 4. It reaches the eyepiece lens 8 via the All+ optical element 5, the condenser lens 6, and the pentaprism 7. This method has the disadvantage that when the subject is viewed through the eyepiece 8, a portion of the light beam passing through the light splitting member 4 is blocked, creating a shadow in the center of the viewing lens. In addition, the area of the light beam taken into the photometric element 5 is determined by the shape of the light splitting member 4, and there is average photometry, etc., which takes the center-weighted photometry as an average image of the entire screen with the center B8 of the screen as the main point. Each measurement area is fixed. Therefore, if it is desired to change the photometry area, it is necessary to replace the condenser lens 6 on which the light splitting member 4 is formed.

In the conventional example shown in FIG. 2, object light transmitted through a photographing lens (not shown) is reflected by a reflex mirror 2, passes through a focusing screen 9, is refracted by a pentaprism 7, and reaches an eyepiece 8. On the other hand, due to the Fresnel lens 10 placed 3Q on the exit surface of the pentaprism 7,
This is a method in which the light is focused on a photometric element 5 provided corresponding to the emission position. In this case, unlike Figure 11, there is no shadow in the center of the viewfinder, but it is not compatible with the photometry method that divides the screen and measures the light, and /r11
It is not easy to switch the optical system, and it is difficult to configure an optical system for this purpose.

In view of these drawbacks, Japanese Patent Laid-Open Publication No. 168039/1983 discloses a technique that attempts to eliminate the above-mentioned drawbacks by providing a photoelectric conversion element for the M&shadow end optical member of the camera.

In other words, in the technology disclosed in the publication, multiple □
By arranging the elements in a dotted manner and connecting the elements with a transparent conductive film that covers the entire surface of the glass substrate on which the elements are provided, a portion of the light that passes through the photographing optical member of the camera can be photoelectrically converted. ing.

In this method, multiple elements are connected with a transparent conductive film so as not to affect the transmitted light, but since the transparent conductive film does not have 100% transmittance, it is difficult to use the photographic optical member. The transmitted light is not only blocked by the plurality of elements, but also blocked by the transparent conductive film, which can make the camera's optical system even darker than the optical system darkened by being blocked by the photoelectric conversion element. There was sex.

Furthermore, in order to connect a plurality of elements arranged in a dotted manner, it is difficult to use a transparent conductive film that covers the entire surface of the glass substrate. This drawback becomes particularly noticeable when the elements are arranged irregularly.

The present invention aims to eliminate the above-mentioned drawbacks, and based on this purpose, the present invention (instead of arranging photoelectric conversion elements in a dotted manner), the photoelectric conversion elements are arranged in a linear manner. The present invention is characterized in that the transparent electrodes arranged to sandwich the photoelectric conversion element have the same shape as the photoelectric conversion element so that the transparent electrodes do not block light passing through the photographing optical member.

(Embodiment) FIG. 3 is a schematic diagram showing an optical system according to an embodiment of the present invention.

In FIG. 3, object light transmitted through a photographic lens (not shown) is reflected by a reflex mirror 21, and then is reflected by a photoelectric conversion element group 22, which is provided at a position slightly shifted from the focal plane, and which is placed in contact with the photoelectric conversion element group 22. The light enters the eyepiece lens 25 via the condenser lens 23 and the pentaprism 24. As shown in FIG. 4, the photoelectric conversion element group 22 is constituted by an array of linear photoelectric conversion element bodies 26 having an irregular pattern.

The structure of this photoelectric conversion element body 26 is, as shown in FIG. 5, formed of a transparent conductive film on a transparent glass plate 27.
A corner electrode 28 having the same shape as the photoelectric conversion element 29 is disposed, and the photoelectric conversion element 29 and the upper electrode 30 are laminated thereon in the same irregular pattern, and the width d of these constituent materials is as follows. It is formed into a fine line of several 4 meters or less.

In FIG. 5, a square pattern is shown instead of an irregular pattern. A lead wire 31. is attached to the end of the electrode 28.30.
32 are connected, the lower electrode 28 and the photoelectric conversion element 2
9. The upper electrode 30 and the lead wires 31, 32 are integrated. Here, an electrode 28 made of a transparent conductive film is not provided at a location where the photoelectric conversion element 29 is not provided.

The photoelectric conversion element 29 has a combination of irregular patterns,
It is divided into several blocks and arranged to be compatible with various FL11 optical systems, and can be switched individually or in combination by a circuit connecting lead wires 31 and 32 connected to the g section of each electrode 28 and 30. is possible.

If CdS or amorphous 5it is simply used for the photoelectric conversion element 29, the photoelectric conversion element 29 will be visible in the finder and the view will be obstructed because these materials have low transmittance to visible light. However, since the width d of the photoelectric conversion element group 26 according to the present invention is several 7 Lm or less,
It is impossible to discern with the naked eye and does not affect the viewfinder view. Furthermore, CdS or amorphous Si can be deposited on the base material of the electrodes 28, 30, etc., and the photoelectric conversion element body 26 can be easily formed, and the pattern of each region can be configured freely, so that center-weighted photometry, Selection of measurement methods such as average photometry can be easily achieved through combinations.

Note that the photoelectric conversion element 29 is made of CdS or amorphous Si.
Other materials may be used instead.

In the optical system shown in FIG. 3, the photoelectric conversion element group 22 is arranged at or near the focal plane, for example, slightly above the focusing plate. Since a Fresnel lens is used in the finder of such an optical system, this Fresnel lens and
Moiré with the pattern of the photoelectric conversion element becomes a problem.

However, according to this embodiment, since the pattern of the photoelectric conversion elements is irregular, moiré does not occur.

FIGS. 6 to 8 are drawings for explaining other embodiments of the present invention. Fig. 6 shows an example of a photoelectric conversion element group in which a total of 12 photoelectric conversion elements are arranged, 3 vertically and 4 horizontally, with an irregular pattern of photoelectric converters 29 on the focal plane.6 The optical system in Fig. 7 is on the incident side of the light beam. In order from reflex mirror 21 to focusing screen 33, condenser lens 23. Photoelectric conversion element group 2
2. The pentaprism 24 and the eyepiece lens 25 are arranged, and the photoelectric conversion element group 22 provided on the entrance surface of the pentaprism 24 and the focal plane on the focusing screen 33 are arranged so as to be slightly larger than each other. There is. In the optical system shown in FIG. 8, the reflex mirror 21. Photoelectric conversion element group 22
．． Focusing screen 33, condenser lens 2
3. The pentaprism 24 and the eyepiece lens 25 are arranged in this order, and the amount of deviation between the photoelectric conversion element group 22 provided in front of the focusing screen 33 and the focal plane is smaller than that in FIG. 7.

As explained above, according to the present invention, a photoelectric conversion device is provided on the light-transmitting surface of either the optical member of the photographing optical system or the finder optical system of the camera, and is sandwiched between electrodes with at least one side being a transparent electrode. In the photometry device for a camera having a photoelectric conversion element, the photoelectric conversion element has a linearly extending shape, and the electrodes sandwiching the photoelectric conversion element have the same shape as the photoelectric conversion element.

Unlike the conventional method of providing a transparent electrode on the entire light-transmitting surface, it is possible to prevent the optical system of the camera from becoming dark due to the transparent electrode, and furthermore, the transparent electrode pattern can be made to have the same shape as the photoelectric conversion element. Therefore, even when such a photometric device is constructed by vapor deposition using a pattern mask,
The transparent electrode and the photoelectric conversion element need only be deposited using the same mask pattern, which has the effect of simplifying the manufacturing process.

[Brief explanation of drawings]

Figures 1 and 2 are cross-sectional views of the optical system of a conventional camera;
The figure is a cross-sectional view of the optical system of a camera having a photometric bag according to an embodiment of the present invention. J is a plan view of a photoelectric conversion element group used in a photometric device according to another embodiment of the present invention, FIG. 5 is a perspective view of a photoelectric conversion element body, and FIG. The plan view of the conversion element group, and FIGS. 7 and 8 are cross-sectional views of other camera optical systems. 21 --- Reflex mirror 22 --- One photoelectric conversion element group 23 --- Condenser lens 26 --- Photoelectric conversion element body 29 --- One photoelectric conversion element 30 --- One partial electrode 31
．． 32---Lead wire

Claims (1)

[Claims] In a photometry device for a camera, the photoelectric conversion element is provided on a light-transmitting surface of either an optical member of a photographing optical system or a finder optical system of the camera, and is sandwiched between electrodes, at least one of which is a transparent electrode. A photometric device for a camera, characterized in that the photoelectric conversion element is formed into a linearly elongated shape, and the electrodes sandwiching the photoelectric conversion element have the same shape as the photoelectric conversion element.