JPH0695213A - Camera provided with lighting system finder - Google Patents

Abstract

PURPOSE:To obtain a camera provided with a lighting system finder whose miniaturization is attained by eliminating a photometry window installed on the front side of the camera main body. CONSTITUTION:As to the camera provided with an eyepiece 7 for observing transmitted light from an objective lens 3, a visual field frame forming member 13 for lighting through a light intake window 12 other than the objective lens 3 and forming a visual field frame forming luminous flux, and also provided with a mirror 6 which is arranged on an optical path between the objective lens 3 and the eyepiece 7 and for transmitting the luminous flux which is made incident on one surface 6a from the objective lens 3 and guiding the flux to the eyepiece 7, and also for reflecting the luminous flux for visual field frame on the other surface 6b and guiding the flux to the eyepiece 7, one surface 6a of the mirror 6 is formed to a half-mirror surface so that a part of the luminous flux from the objective lens 3 may be transmitted through the mirror and also some other beams may be reflected on the mirror. A photometry element 23 is arranged on a position where the light reflected on the half-mirror surface 6a can be received.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera having a daylighting finder.

[0002]

2. Description of the Related Art Generally, a daylighting finder has a first optical system for confirming a subject image and a second optical system for displaying a visual field frame on the subject image in a superimposed manner. Therefore, in addition to the objective window for taking the subject light into the camera body, it is necessary to provide a daylighting window for forming the field frame on the front surface of the camera body. On the other hand, the camera is provided with a photometric device for receiving the subject light and detecting the subject brightness, and a photometric window for guiding the subject light to the photometric device is also provided on the front surface of the camera.

[0003]

However, in addition to the windows described above, it is necessary to dispose a light emitting window of the electronic flash device, a distance measuring window, and a photographing lens on the front surface of the camera. The configuration requires a lot of space in front of the camera body, which causes a problem of increasing the size of the camera.

It is an object of the present invention to provide a camera having a daylighting finder in which the photometric window on the front surface of the camera body is eliminated and the size of the camera is reduced.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1 showing an embodiment, the present invention will be described. In the present invention, an objective lens 3 on which a subject light is incident, and a light transmitted through the objective lens 3 are observed. A lighting window 1 separate from the eyepiece 7 and the objective lens 3.
The light flux from the objective lens 3 which is arranged in the optical path between the objective lens 3 and the eyepiece 7 and which is incident on the one surface 6a, and the visual field frame forming member 13 which forms the luminous flux for the visual field frame. A mirror 6 for transmitting the light beam for the field frame to the eyepiece lens 7 and reflecting the light beam for the field frame on the other surface 6b to the eyepiece lens 7; and a photometric element 23 for receiving the subject light and detecting the subject brightness. Applies to equipped cameras. Then, the following problems are solved by the following configuration. That is,
One surface 6a of the mirror 6 is a half mirror surface that transmits a part of the light beam from the objective lens 3 and reflects the other part of the light beam.
The photometric element 23 is arranged at a position capable of receiving the reflected light. In particular, claim 2 is provided with a condenser lens 22 which condenses the reflected light on the half mirror surface 6a and guides it to the photometric element 23. The condenser lens 22 and the photometric element 23 are provided behind the light emitting portion 31 of the electronic flash device. It was placed in.

[0006]

Operation: Part of the transmitted light of the objective lens 3 is reflected by the mirror 6
While being transmitted through and observed by the eyepiece 7, the other part of the light flux is reflected by the half mirror surface 6a and guided to the photometric element 23. The photometric element 23 outputs a subject brightness signal according to the amount of received light. According to this configuration, it is not necessary to provide a light metering window dedicated to photometry on the front surface of the camera, the space on the front surface of the camera can be effectively used, and the camera can be downsized. Further, if the condenser lens 22 and the photometric element 23 are arranged behind the light emitting portion 31 of the electronic flash device as in claim 2, the space in the camera body can be effectively used, and the size of the camera can be further reduced. Can be realized.

Incidentally, in the section of means and action for solving the above problems for explaining the constitution of the present invention, the drawings of the embodiments are used for making the present invention easy to understand. It is not limited to.

[0008]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a sectional view of an essential part of a camera according to the present invention seen from above, and FIG. 2 is a front view of the camera.
Reference numeral 1 in FIG. 1 denotes a first optical system, and the first optical system 1 includes a finder window 2 (also shown in FIG. 2) provided on the front surface of the camera body 51 and immediately after the finder window 2. The objective lens 3 arranged at the rear of the objective lens 3, the first and second prisms 4 and 5 arranged at the rear of the objective lens 3, and the eyepiece lens 7 arranged at the rear of the second prism 5. ing. The rear surface 4a of the first prism 4 is inclined by 45 degrees with respect to the optical axis, the front surface 5a of the second prism 5 is brought into close contact with the rear surface 4a, and the half mirror 6 is formed on the close contact surface.

In the thus constructed first optical system 1, the subject light taken in through the finder window 2 passes through the objective lens 3 and then passes through the first prism 4 to pass through one of the half mirrors 6. It is guided to the surface 6a. A part of this light flux is transmitted through the half mirror 6, then is transmitted through the second prism 5 and is observed by the eyepiece lens 7, and another part of the light flux is reflected by the surface 6a to the right in the figure. .

A second optical system 1 is provided on the side of the first optical system 1.
1 is provided, and the second optical system 11 includes a camera body 5
1 and a field frame plate (field frame forming member) 13 provided immediately after the daylighting window 12;
The reflection mirror 14 arranged behind the field frame plate 13
And a field lens 15 provided in the reflection direction of the reflection mirror 14. In addition, the above-mentioned first,
The second prisms 4 and 5 and the half mirror 6 are also used as constituent elements of the second optical system 11. Here, the field frame plate 13 has slits formed in the shape of the field frame.

In the thus constructed second optical system 11, the light beam taken in from the daylighting window 12 passes through the slit of the field frame plate 13 and is then guided to the reflection mirror 14 as a field frame light beam. The light reflected by the reflection mirror 14 is
The light enters the second prism 5 from the side surface through the field lens 15, and then is reflected by the other surface 6b of the half mirror 6 and reaches the eyepiece 7. Thereby, the virtual image of the field frame can be observed in a state of being superimposed on the subject image.

On the other hand, reference numeral 21 denotes a third optical system, and this third optical system 21 is a finder window 2, an objective lens 3, a first prism 4, a half, which constitutes the above-mentioned first optical system 1. It also serves as the mirror 6. A condenser lens 22 is provided on the right side of the first prism 4, and a photometric element 23 is disposed behind the optical path of the condenser lens 22. here,
Reference numeral 31 in FIG. 1 denotes a light emitting portion of the electronic flash device, and the condenser lens 22 and the photometric element 23 are arranged behind the light emitting portion 31.

In the third optical system 21, the subject light from the viewfinder window 2 passes through the objective lens 3 and the first light
After entering the prism 4 and reaching the half mirror 6,
The light is reflected to the right by one surface 6 a of the half mirror 6, is converged by the condenser lens 22, and is received by the photometric element 23. The photometric element 23 outputs an electric signal corresponding to the received light as a subject brightness signal to a photometric circuit (not shown). The illumination light from the light emitting unit 31 passes through a light emitting window 32 provided on the front surface of the camera body 51 and is applied to a subject.

On the other hand, on the left side of the second optical system 11, an autofocus (AF) optical system 41 is provided. The AF optical system 41 includes a light projecting optical system 42 and a light receiving optical system 43.
The light projecting optical system 42 includes a light projecting element 44, a light projecting lens 45, and a light projecting window 46.
3 is a light receiving window 47, a light receiving lens 48, and a light receiving element 49.
It consists of Projecting element 44 to projecting lens 45
And infrared light is emitted to the subject through the light projecting window 46,
Light reflected from the subject is received by the light receiving window 47 and the light receiving lens 48.
The light is received by the light receiving element 49 via. Then, the distance from the light receiving position of the light receiving element 49 to the subject is measured, and focusing of the taking lens 52 (FIG. 2) is performed based on this distance.

As described above, in the present embodiment, photometry can be performed using the subject light that has passed through the finder window 2 and the objective lens 3, so there is no need to provide a dedicated light metering window on the front of the camera. In the above description, the daylighting window 12 for forming the field frame is arranged in front of the camera.
This may be arranged on the upper surface of the camera, and its optical path may be changed by 90 degrees by a reflection mirror to guide the field frame light flux to the field lens 15 side.

[0016]

Since the present invention is configured as described above, it is possible to use both the finder window portion for confirming the subject image and the photometric window portion, and there is no need to provide a dedicated photometric lighting window in front of the camera. Therefore, the space in front of the camera can be effectively used, and the camera can be downsized. Particularly, according to the second aspect of the invention, since the condenser lens and the photometric element are arranged behind the light emitting portion of the electronic flash device, the space efficiency inside the camera can be improved and the camera can be further downsized.

[Brief description of drawings]

FIG. 1 is a plan sectional view showing an optical system of a camera having a daylighting finder according to the present invention.

FIG. 2 is a front view showing the appearance of the camera.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st optical system 3 Objective lens 6 Half mirror 6a One surface 6b The other surface 7 Eyepiece 11 Second optical system 12 Daylighting window 13 Field frame plate 21 Third optical system 22 Condenser lens 23 Light receiving element 31 Light emitting part 51 Camera body

Claims (2)

[Claims] 1. An objective lens on which object light is incident, an eyepiece for observing the transmitted light of the objective lens, and light is collected from a lighting window separate from the objective lens to form a luminous flux for a field frame. A visual field frame forming member, which is disposed in the optical path between the objective lens and the eyepiece lens, transmits the light flux from the objective lens incident on one surface and guides it to the eyepiece lens, and for the visual field frame In a camera provided with a mirror that reflects a light beam on the other surface and guides it to the eyepiece lens, and a photometric element that receives subject light and detects subject brightness, the one surface of the mirror is from the objective lens. Is a half mirror surface that transmits a part of the light flux and reflects the other part, and the photometric element is arranged at a position where the light reflected by the half mirror surface can be received. A camera with a daylighting viewfinder. 2. A condensing lens for condensing the reflected light on the half mirror surface and guiding it to the photometric element, and the condensing lens and the photometric element are arranged behind a light emitting portion of the electronic flash device. A camera having a daylighting finder according to claim 1.