JPH043533B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tilt adjustment mechanism for, for example, a light receiving element for exposure control or a light receiving element for distance measurement in a single-lens reflex camera.

For example, in a single-lens reflex camera,
In order to guide the incident light from the photographic lens to the light receiving element for exposure control or the light receiving element for distance measurement, a part of the incident light is transmitted through the main mirror for viewfinder and then reflected by the sub-mirror behind the main mirror, and then the light is received. There is one that leads to the element. In order to perform accurate photometry or distance measurement, the light-receiving surface of this light-receiving element is required to have no inclination with respect to the incident optical axis and no one-sided blurring. The inclination of the light-receiving surface of the light-receiving element with respect to the incident optical axis includes a left-right inclination and a front-back inclination when looking at the front of the camera. Adjustment screws were brought into contact with each of the three points, and the inclination of the light-receiving element was adjusted using the adjustment screws.

According to this conventional adjustment mechanism, the configuration is simple, but for example, if you try to adjust the tilt in the left-right direction, the tilt in the front-back direction will also change, and if you try to adjust the tilt in the front-back direction, the tilt in the left-right direction will also change. , adjustment is extremely troublesome. Moreover, in the case of a distance-measuring light-receiving element, when adjusting the focus, three adjusting screws must be moved by the same amount at the same time, which inevitably causes tilting. In this case, if the adjustment is performed using optical means using a collimator,
Since the left/right and front/rear tilts can be evaluated simultaneously, it is not that troublesome to make adjustments, but in the case of distance-measuring photodetectors, evaluations of left/right tilts and front/rear tilts are performed separately because they are evaluated electrically. Therefore, in order to see the change in the other slope caused by adjusting one slope, it is necessary to switch the electrical output and perform the evaluation, making the adjustment extremely troublesome.

An object of the present invention is to provide a tilt adjustment mechanism for a light receiving element, which allows the front and rear and left and right tilts of the light receiving element to be adjusted independently, thereby shortening the adjustment time and, in turn, reducing production costs. Our goal is to provide the following.

The present invention will be explained below with reference to illustrated embodiments.

In FIGS. 1 and 2, a main mirror 1 is installed obliquely on the incident optical path from the photographic lens, and most of the incident light is reflected upward by the mirror 1 and is imaged on a focusing glass (not shown). Also, a part of the incident light that has passed through the mirror 1 is reflected downward by a sub-mirror 2 installed diagonally behind the main mirror 1, and is made to enter the light-receiving element 3. .

In FIGS. 1 to 4, the light-receiving element 3 is held on the element substrate 4 by appropriate means with the light-receiving surface facing upward. Below the element substrate 4, there is a planar shape U having both side plates 5a and 5b parallel to each other.
There is a letter-shaped element support plate 5 located at the rear of the element substrate 4 (the right side in Fig. 1, the upper part in Fig. 3).
The downward bent portions 4a and 4b formed on both sides are connected to the side plate 5 of the element support plate 5 by shafts 6 and 7, respectively.
It is pivotally attached to the rear of parts a and 5b. Element support plate 5
The tip of one side plate 5b is pivotally attached to the tip of the first lever 8 by a shaft 9. The first lever 8 is provided parallel to the side plate 5b of the element support plate 5, and its base end is pivotally attached to the fixed shaft 10 so as to be rotatable in a vertical plane. Due to the elasticity of the spring 11, the first lever 8 is moved to a second position around the shaft 10.
The lever 8 has a tendency to rotate clockwise in the figure and counterclockwise in Figure 4.
The tip of the left-right tilt adjustment screw 12 comes into contact with the lower surface of the bent portion 8a formed on the lower edge, thereby restricting the rotation due to the above-mentioned behavior.

The tip of the other side plate 5a of the element support plate 5 is pivotally attached to a fixed shaft 14, and a second
The base end of the lever 15 is pivotally mounted. The second lever 15 is provided parallel to the side plate 5a of the element support plate 5, and is rotatable in a vertical plane about the fixed shaft 14. Although it has a tendency to rotate clockwise, the tip of the longitudinal inclination adjusting screw 17 comes into contact with the lower surface of the bent portion 15a, thereby restricting the rotation due to the above-mentioned tendency.
An intermediary lever 19 is pivotally attached to the tip of the second lever 15 via a shaft 18 so as to be rotatable in a vertical plane. The intermediate lever 19 is connected to the side plate 5a of the element support plate 5.
and the second lever 15. The intermediary lever 19 has pins 19a and 19b at positions with different rotation radii, respectively.
These pins 19a and 19b enter between the side plate 5a of the element support plate 5 and the element substrate 4. A wound portion of a spring 20 is inserted into the shaft 6, and the spring 20
One end of the spring 20 is hung on the lower edge of the side plate 5a of the element support plate 5, and the other end of the spring 20 is hung on the bent part 4c of the element substrate 4. are biased so that they are attracted to each other. However, this element substrate 4 and element support plate 5
The distance between the two is regulated by the pin 19a of the intermediate lever 19 hitting the upper edge of the side plate 5a of the element support plate 5, and the pin 19b of the intermediate lever 19 hitting the lower surface of the element substrate 4. There is. A bent portion 5c is provided at the lower edge of the side plate 5a of the element support plate 5, and the tip of the focus adjustment screw 21 is in contact with the lower surface of this bent portion 5c. Therefore, screw 2
1, the element support plate 5 rotates around the fixed shaft 14, and the fulcrum of the element substrate 4 moves up and down accordingly, and the element substrate 4 attempts to rotate relatively. As the plate 5 rotates, the pin 19a of the intermediate lever 19 is moved up and down by the side plate 5a of the element support plate 5 and rotated about the shaft 18, and the position near the free edge of the element substrate 4 is moved up and down by the side plate 5a of the element support plate 5. It is moved up and down by the other pin 19b of the lever 19. Here, the position of the shaft 18 of the intermediate lever 19, 2
The conditions such as the rotation radius of the two pins 19a and 19b are as follows:
When the element support plate 5 rotates about the fixed shaft 14, the element substrate 4 is set to move vertically in parallel. The light receiving element 3 moves vertically in parallel while maintaining a constant posture with respect to the incident optical axis.

It is assumed that each of the adjustment screws 12, 17, and 21 is screwed into a predetermined stationary part, for example, the bottom plate of a mirror box.

Next, the operation of the above embodiment will be explained. Now, when trying to adjust the horizontal inclination of the light receiving element 3, that is, the difference in level between the left side and the right side in FIG. 3, the adjustment is done by turning the adjustment screw 12. screw 1
2, the bent portion 8a of the first lever 8 moves up and down, the lever 8 rotates, and the height position of the shaft 9 changes. Accordingly, one side plate 5b of the element support plate 5
Since the lower edge bent portion 5c of the other side plate 5a is in a substantially fixed state, it moves up and down using the fixed shaft 14 and the bent portion 5c as supporting surfaces,
Along with this, the pin 19b of the intermediate lever 19 and the shaft 6
The element substrate 4 whose one end side (left end side in FIG. 4) is fixed by the above-mentioned pin 19b and shaft 6 is also moved up and down using the pin 19b and the shaft 6 as supporting surfaces, and the light-receiving element You can adjust the left and right tilt of 3. At this time, the light receiving element 3 and the element substrate 4
The posture in the front-rear direction, that is, the level position of the upper arm in FIG. 3 does not change at all. In addition, in the case of adjusting the left and right tilt as described above, there is no special rotation axis, but the tilt of the light receiving element is originally adjusted within an extremely small range, and the angle between the element support plate 5 and the shaft 14 is This is allowed by a slight wobbling or a slight deflection of the element support plate 5.
Of course, if necessary, a shaft may be provided that allows the element support plate 5 and the like to be tilted from side to side.

Next, when attempting to adjust the inclination of the light-receiving element 3 in the front-rear direction, the adjustment screw 17 is turned. The rotation of the screw 17 causes the second lever 15 to rotate, and the position of the shaft 18 to move up and down, so that the element substrate 4
This is substantially the same as if the intermediary lever 19, which has pins 19a and 19b held between the and the element support plate 5 by the elasticity of the spring 20, rotates about the pin 19a as a fulcrum. As a result, the height position of the pin 19b changes, and while the height position of the shafts 6 and 7 of the element substrate 4 remains unchanged, the level of the free end changes, and as a result, the element substrate 4 and the light receiving element 3 in the front-rear direction will be adjusted. At this time, there is no change in the horizontal orientation of the light receiving element substrate 4.

After adjusting the front-back and left-right tilts of the light-receiving element 3 in this way, the light-receiving surface of the light-receiving element 3 is adjusted so that the image is correctly formed on the light-receiving surface of the light-receiving element 3, that is, the light-receiving surface of the light-receiving element is precisely in a position conjugate with the photographic film surface. When attempting to adjust the focus, rotate the focus adjustment screw 21. As described above, the rotation of the screw 21 causes the element support plate 5 to rotate around the shafts 14 and 9. Along with this, the shafts 6 and 7 move up and down, and the intermediate lever 19 also rotates around the shaft 18 due to the up and down movement of the pin 19a engaged with the upper edge of the side plate 5a of the element support plate 5. , since the pin 19b at the other end also moves up and down in the same direction and the same distance as the shafts 6 and 7, the element substrate 4 and the light receiving element 3 are kept in a constant state by the shafts 6 and 7 and the pin 19b, and are parallel to the optical axis direction. The object moves and the focus is adjusted. At this time, the light-receiving element and the substrate 4 do not tilt forward or backward or left or right.

As described above, according to the present invention, one end of the first lever and the second lever is rotatably supported by the fixed shaft, one corner of the element support plate is rotatably supported by the fixed shaft, and further, By linking the element substrate, the element support plate, the first lever, the second lever, and the intermediary lever in a pivoting or abutting relationship, the light-receiving element can be tilted in the left-right direction and the front-back direction independently. Therefore, the tilt of the light receiving element can be adjusted much more easily than with conventional mechanisms. This is particularly effective when adjusting the inclination or focus of a light receiving element while electrically evaluating it, such as in the case of a distance measuring light receiving element.

In the illustrated embodiment, the light-receiving element adjustment mechanism is applied to a single-lens reflex camera, but it can be applied to any device that uses a light-receiving element.

[Brief explanation of drawings]

Figure 1 is a right side view showing an embodiment of the present invention, Figure 2 is a right side view showing an embodiment of the present invention.
The figure is a left side view of the same as above, the third figure is a plan view, and the fourth figure is a top view.
The figure is also an exploded slope view. 3... Light receiving element, 4... Element substrate, 5... Element support plate, 6, 7... Shaft, 8... First lever, 9...
...Axis, 10...Fixed shaft, 12...Right and left tilt adjustment screw, 14...Fixed shaft, 15...Second lever, 17
...Backward tilt adjustment screw, 18...shaft, 19...intermediate lever, 19a, 19b...pin.

Claims (1)

[Scope of Claims] 1. An element substrate that holds a light-receiving element, and an element support plate whose one corner is rotatably supported by a fixed shaft and whose free end is pivoted to one end of the element substrate. , one end of which is rotatably supported by a fixed shaft, and a free end of which is pivotally connected to one corner of the element support plate and to one corner of the element substrate opposite to the fixed shaft; a second lever, which is disposed on the opposite side of the first lever with the element support plate in between and is rotatably supported by a fixed shaft on the same side of the element support plate as the fixed shaft; an intermediary lever pivotally attached to one end of the second lever and abutting the element substrate and the element support plate at positions at different distances from the pivoting portion; A tilt adjustment mechanism for a light-receiving element, characterized in that the tilt of the light-receiving element in the left-right direction and the tilt in the front-rear direction can be adjusted independently by independently rotating the second lever about a fixed axis.