JPH09258290A - Photometric device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make an adjusting space necessary for a photometric block small and to miniaturize a camera by providing a supporting position adjusting member including 1st to 3rd adjusting parts specified respectively. SOLUTION: The photometric block 5 is mounted on a photometric block base 13 through three adjusting machine screws 10 to 12 functioning as the adjusting member by means of three-point adjustment. By rotating the screws 10 and 11 in a reverse direction respectively, the arm parts 5b and 5c of the block 5 are moved up and down in the reverse direction, and only the angle of the block 5 to the optical axis direction of a photometric image-formation lens is changed in directions A and B without changing the position of the photometric imageformation lens in the optical axis direction so as to adjust the block 5 in a right-and-left direction with respect to a focusing screen 2. Thereafter, by moving the screw 12 by setting the machine screw 10 which finishes adjusting action as reference, only the height of the arm part 5d of the block 5 is changed without changing the height of the arm part 5b, and the angle of the block 5 to the optical axis of the photometric image-formation lens is changed in directions C and D so as to adjust the block 5 in an up-and- down direction with respect to the focusing screen 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention forms a primary image formed on a finder screen (focus plate) as a secondary image on a photometric element (sensor) including a plurality of elements by a re-imaging optical system. The present invention relates to a photometric device for performing photometry.

[0002]

2. Description of the Related Art Conventionally, a subject image formed on a viewfinder screen (focus plate) of a camera is formed on a sensor (photometering element) composed of a plurality of elements by a re-imaging optical system (photometric imaging lens). There is known a photometric device for a camera that performs photometry by dividing a shooting screen into a plurality of parts. In this type of camera, unless the relative positions of the photometric element and the secondary image formed on the photometric element are aligned with the predetermined positional relationship in the design, the screen area for photometry by the photometric element and the screen area for shooting are There is a case that the desired exposure cannot be obtained due to the misalignment.

Therefore, in regard to the adjusting mechanism of the photometric element of the camera, Japanese Utility Model Publication No. 4-104610, Japanese Patent Application No. 2-117124 (Japanese Utility Model Application No. 4-72229) and Japanese Utility Model Application No. 59-18899 ( Actual development Sho 60-130413
No.), there is proposed a mechanism for adjusting the position of the photometry element with respect to the focus plate of the camera by moving the photometry element in the XY directions with respect to the focus plate of the camera. Japanese Patent Application No. 5-52632
No. 265966) has been proposed.

[0004]

However, Japanese Patent Laid-Open No. 6-2 / 1994
In No. 65966, the degree of freedom in adjusting the relative position between the photometric element and the secondary image formed thereon is high, and the relative position with the secondary image can be adjusted with high resolution. Since the point support adjustment mechanism is used, if the relative position between the photometric element and the secondary image formed on this element is significantly deviated, the photometric imaging lens must be tilted greatly. Not only the inclination of, but also the distance of the photometric imaging lens from the viewfinder screen will change.

At this time, if the pentaprism and the photometric imaging lens are close to each other, or if there is an optical path changing reflection member (photometric prism) between the pentaprism and the photometric imaging lens, the photometric prism and the photometric imaging lens are arranged. When the and are close to each other, the photometric imaging lens may interfere with the penta prism or the photometric prism. In this case, it is not possible to secure a sufficient margin for adjusting the tilt of the photometric imaging lens, and it becomes impossible to perform adjustment with high resolution and a high degree of freedom in adjustment.

Further, in order to secure a sufficient margin for adjusting the tilt of the photometric imaging lens in order to perform the adjustment with high resolution and a high degree of freedom of adjustment, the distance between the photometric imaging lens and the penta prism or the photometric prism is increased. There was a problem that the camera would become large and small.

The present invention has been made in view of the above problems, and an object of the present invention is to reduce the adjustment space required for the photometric block and to downsize the camera.

[0008]

To achieve this object, a photometric device of the present invention measures a photometric element (7) including a plurality of elements and a subject image formed as a primary image on a focusing screen. A re-imaging optical system (6) for re-imaging as a secondary image on the element, a holding member (5) for integrally holding the re-imaging optical system and the photometric element, and three supports arranged in a triangular shape. Supporting members (9a to 9c) for supporting the holding member at the points in the optical axis direction of the re-imaging optical system, and the first and second supporting members.
First and second adjusting parts (10, 11) for adjusting the supporting position of the holding member in a predetermined direction with respect to the focusing screen by the supporting point
And a third position for adjusting the support position of the holding member in a direction different from the predetermined direction with respect to the focusing screen with reference to the first support point.
A support position adjusting member (10, 1) including an adjusting part (12).
1, 12) and.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing an embodiment of a photometric device according to the present invention. FIG. 2 is a cross-sectional view showing an embodiment of the photometric device according to the present invention. FIG. 3 is a vertical sectional view showing an embodiment of the photometric device according to the present invention.

In FIG. 1, light from a subject (not shown) passes through a taking lens (not shown) and is reflected by a quick return mirror 1 to be focused on a focusing screen 2. The subject image formed on the focusing screen 2 passes through the pentaprism 3 and the eyepiece lens group 4 and is visually recognized by the photographer. 2 and 3 will be described together.

Reference numeral 5 is a photometric element base, and 6 is a photometric imaging lens for forming a subject image formed on the focusing screen 2 on the photometric element 7. The photometric imaging lens 6 includes the mounting arm 6
Hold a at the left and right, and the guide hole 6b in this arm 6a
A diaphragm plate 18 is attached to the guide boss portion 5a on the lower side of the photometric element base 5.
It is fixed with the photometering element base 5 by sandwiching it.
A photometric element 7 is adhesively attached to the upper part of the photometric element base 5 so as to be aligned with the optical axis of the photometric imaging lens 6, and these four parts form a photometric block. That is, in this embodiment,
The length between the photometric imaging lens 6 and the photometric element 7 cannot be adjusted. Further, in this embodiment, the light is guided to the light measuring block by using the light measuring prism 8 attached to the eyepiece lens stand 17 (see FIG. 1).

A hot shoe block 16 for an external strobe is attached to the finder cover 15 above the photometric block. The metering block space is small, so the viewfinder cover 1
5 is provided with a step, and the hot shoe block 1 is provided in the step.
6 is attached to the finder cover 15 without making it convex (see FIG. 3).

The photometric block comprises three adjusting screws 10, 11, and 1 as adjusting means by so-called three-point adjustment.
2 is mounted on the photometric block 13 and is arranged behind the pentaprism 3 and above the eyepiece lens group 4.

Further, the photometric block and the photometric block base 1
Three urging springs 9a, 9b and 9c are contracted between 3 and the shaft portions of the adjusting screws 10, 11 and 12 are inserted therethrough. In other words, the photometric block is constantly urged upward by the three urging springs 9a, 9b, and 9c, and is regulated by the heads of the adjusting screws 10, 11, and 12 to prevent upward ejection. There is. Adjustment screw 1
The tips of the shafts of 0, 11, and 12 are crimped to the photometric block base more than the adjustment allowance, and adjustment screws 10, 1 are provided on the inner diameter.
It is screwed into three adjusting screw receivers 14a, 14b and 14c which are threaded with female screws for fitting with 1 and 12.

Three adjusting screws 10, 11, and 12
Is approximately parallel to the lateral direction of the photometric element 7 and the photometric imaging lens 6 is a distance l between the two adjusting screws 10 and 11.
1 so as to be arranged on the approximate center line, and so as to be arranged substantially parallel to the photometric element 7 with the adjusting screw 10 as a reference,
Also, the distance l2 between the adjusting screws 10 and 12 is l2 <
The adjusting screw 12 is arranged so as to be 11.

As an example of a specific adjusting method, first,
By rotating the adjusting screws 10 and 11 in the opposite directions, the arm portions 5b and 5c of the photometric block 5 are moved up and down in the opposite direction, and the photometric imaging is performed without changing the position of the photometric imaging lens 6 in the optical axis direction. Only the angle of the lens 6 with respect to the optical axis is changed to the A direction and the B direction (FIG. 2), and the left and right (X) direction with respect to the focusing screen 2 is adjusted.

After that, the adjusting screw 12 is moved with the adjusted adjusting screw 10 as a reference, and the arm portion 5 of the photometric block 5 is moved.
By changing only the height of the arm portion 5d without changing the height of b, the angles of the photometric imaging lens 6 with respect to the optical axis are changed in the C direction and the D direction (FIG. 3), and the vertical direction (Y) with respect to the focusing screen 2 is changed. Adjust the direction. At this time, the position of the photometric imaging lens 6 in the optical axis direction changes, but due to the relationship of l2 <l1, the amount of change in position is suppressed to a small amount.

[0019]

As described above, according to the photometric device of the present invention, the supporting position of the holding member by the first and second supporting points of the supporting members (9a-9c) in the predetermined direction with respect to the focusing screen is determined. First and second adjusting parts (10, 11) for adjustment
And a third position for adjusting the support position of the holding member in a direction different from the predetermined direction with respect to the focusing screen with reference to the first support point.
A support position adjusting member (10, 1) including an adjusting part (12).
1) and 12) are provided, it is possible to secure a wide adjustment angle width for adjusting the center of the photometric element to the center of the finder screen without changing the position of the photometric block, so that the adjustment space required for the photometric block can be increased. The size of the camera can be reduced and the size of the camera can be reduced. Further, since the distance between the photometric imaging lens and the penta prism or the photometric prism can be set to be small, the effect of miniaturizing the camera can be obtained.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a photometric device according to the present invention.

FIG. 2 is a cross-sectional view showing an embodiment of the photometric device according to the present invention.

FIG. 3 is a vertical sectional view showing an embodiment of the photometric device according to the present invention.

[Explanation of symbols]

 3 pentaprism 5 photometric element base 6 photometric imaging lens 7 photometric element block 9 biasing springs 10, 11, 12 adjustment screw 13 photometric block base

Claims (3)

[Claims] 1. A photometric element including a plurality of elements; a re-imaging optical system for re-imaging a subject image formed as a primary image on a focusing screen as a secondary image on the photometric element; A holding member for integrally holding the image optical system and the photometric element; a supporting member for supporting the holding member in the optical axis direction of the re-imaging optical system at three supporting points arranged in a triangular shape; First and second adjusting portions for adjusting the supporting position of the holding member in the predetermined direction with respect to the focusing screen by the first and second supporting points of the members, and the holding member with the first supporting point as a reference. And a supporting position adjusting member including a third adjusting portion for adjusting a supporting position in a direction different from the predetermined direction with respect to the focusing screen. 2. A distance between the first supporting point and the second supporting point is l1, and a distance between the first supporting point and the third supporting point is l2.
The photometric device according to claim 1, wherein l1> l2. 3. The support member is a spring member that elastically supports the holding member in the optical axis direction of the re-imaging optical system, and the support position adjusting member adjusts a compression amount of the spring member. It is a screw member for doing.
Alternatively, the photometric device according to claim 2.