JP2888408B2 - Stereo microscope - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stereo microscope.

[0002]

2. Description of the Related Art Since a stereo microscope is required to be able to observe an erect image, a prism such as a Porro prism or a roof prism is incorporated in a lens barrel. In addition, stereo microscopes have been used for operations and operations on samples from the past. With the advancement of operations and operations in the semiconductor and biotechnology fields in recent years, the working distance has been long, the magnification has been high, and the microscope has been used for eyesight. A short distance to the point is required, and several different barrel angles are required depending on the device.

[0003] As one optical system of a conventional stereo microscope,
For example, FIG. 4 ((a), (b), (c) is a side view,
It is a front view and a front view. ), As shown in FIG.
3 and 4 are arranged the same as the reflection surface of the Porro II prism
Is arranged on the optical axis of the objective lens 5, and the reflecting surfaces 2 and
The lens barrel angle can be freely changed depending on the angle of 3, 4
There is something. However, this is due to the reflection surfaces 1, 2, 3, 4
Is determined by the lens position, etc.Four anti
It is difficult to adjust the arrangement of each launch surface with high accuracy.And
In both cases, the lens barrel length is constant, and the lens barrel angle is θ.
The reflection angle on the reflection surface 2 must be (90 ° + θ) / 2
Had a rule that the image would fall if the
The height of the eye point varies greatly depending on the cylinder angle
There was a problem of getting around. For example, FIG. 4 (a) and FIG.
By comparison, (l₂sin60 ° -l₁cos 75 °)-(l₂si
n45 ° -l₁cos 67.5 °) = 0.12 l₁ +
0.16 l₂  Height differences occur. In addition, the eye point is a human
Refers to the position of the eye when observing. Also, as shown in FIG.
As shown in the figure, the optical path extends horizontally, so the lens barrel width is large.
Rotate the main optical axis to adjust the interpupillary distance
Since the optical system is rotated as an axis, especially the reflecting surface 3
It is greatly shaken by being away from the axis,
Since the lens barrel becomes wider, it is compact
There was a problem that could not be achieved.

FIGS. 6 and 7 show an example in which the roof prism 6 is used. In this case, since the optical path is not folded back, if the lens barrel length (optical path length) is long, the mark is left as it is.
There was a problem that the distance from the book to the eye point would be long . This also has a problem that the eye point greatly changes depending on the lens barrel angle. or,
The roof prism 6 is expensive, and the roof prism 6 is fixed and requires a prism 6 having a different shape for each lens barrel angle.
Also, if the objective lens 5 having a long working distance and high magnification is used, a long lens barrel length is naturally required. However, since the optical path is not folded in this case as described above, the distance from the specimen to the eye point is short. There was a problem that it could not be configured to be.

[0005]

[0008] In view of the above problems, does not change much the height of the eye point be changed barrel angle distance from the sample to the eye point is rather short,
It is an object of the present invention to provide an inexpensive and compact stereomicroscope having a small lens barrel width .

[0006]

A stereomicroscope according to the present invention is a stereomicroscope which adjusts the interpupillary distance by rotating the left and right optical systems in opposite directions about the optical axis of each objective lens as a rotation axis. An optical system comprising: a Porro prism; a first reflecting surface for deflecting an emission optical axis of the Porro prism downward and a second reflecting surface for deflecting an emission optical axis of the first reflection surface upward; And the second reflection surface has a direction opposite to a rotation direction of a convergence angle with an optical axis emitted from the first reflection surface as a rotation axis so that the image inclination is canceled at a predetermined interpupillary distance. And is arranged to be rotated at a predetermined angle. Preferably, the predetermined interpupillary distance is substantially near the center of the interpupillary distance adjustable range.

That is, according to this configuration, since the optical path is folded, the distance from the specimen to the eye point is short even in the case of a long lens barrel. Further, since the lens barrel angle is changed only by changing the angle of inclination of the second reflecting surface in the plane including the incident and output optical axes, the lens barrel angle can be easily changed, and the eye point can be easily changed. Height does not change much. Further, since the roof prism is not required, the prism does not need to be changed even if the lens barrel angle is changed, and the frame and cover of the reflecting surface can be shared up to the first reflecting surface, so that the cost is reduced. In addition, image tilt can be easily removed only by adjusting the arrangement of the second reflecting surface. Furthermore, since the part that expands the optical path in the horizontal direction is only the part of the root Porro prism,
The lens barrel width can be made compact.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the illustrated embodiments. Figure 1 (a) and (b) is a side view and a front view of the optical system of each first embodiment, O specimens, 7 objective lens, 8 on the exit optical axis L ₁ of the objective lens 7 The arranged Polo II prism, 9 is the Polo II prism 8
First reflecting surface for deflecting the said output Shako axis L ₂ forward downward (FIGS. 1 (a) lower right) have been placed on the exit optical axis L _2,
10 the first and the front upper (FIGS. 1 (a) upper right) exit optical axis L ₄ are deflected to be arranged on the exit optical axis L ₃ and the said output Shako axis L ₃ of the first reflection surface 9 The second reflective surface , E is eye
Is the point . The second reflecting surface 10 of which rotates the exiting optical axis L ₃ of the first reflection surface 9 as a rotation axis, the rotation angle, the image in the pupil distance adjusting range desirably adjustment range center by experiment or vector calculations The angle has been rotated so that it does not fall.

The method of calculating the vector is as follows. First, on the reflective surface And of the incident light And the reflected light The formula for Becomes here Is represented by k = −2 cos θ where θ is the angle formed by Becomes From this relationship, A matrix indicating the vector rotation due to reflection (r ₁ ) is given by

When this is performed for each reflecting surface and the conversion is sequentially performed, a vector on the sample surface can be converted into a vector on the image surface. When the vector corresponding to the vertical direction of the image is converted from the object side and the vectors obtained on the right and left sides are parallel to each other, the image does not collapse. The rotation angle of the second reflecting surface 10 is, based on experience, the angle 0 °.
Exists in the range of 10 °. The inclination of the first reflecting surface 9 is suitably set so that the reflection angle α is 15 ° to 25 °.

Then, as is clear from FIG.
An optical system composed of an objective lens 7, a Porro II prism 8, and reflecting surfaces 9, 10 is symmetrically arranged with a pair of inward angles, and this pair of optical systems is connected to the optical axis L ₁ of each objective lens 7.
The eye width is adjusted by rotating them in directions opposite to each other with the rotation axis as a rotation axis.

The present embodiment is configured as described above. In order to remove the left and right images caused when the interpupillary distance adjustment is performed by the Greenaw type as in the present embodiment, the second reflecting surface 10 is used. rotation is made an optical axis L ₃ as an axis. Ideally,
Since it is better for the rotation angle to be different for each interpupillary distance, the rotation angle may be changed by a link, gear, or the like in conjunction with interpupillary distance adjustment. However, if you do so, the mechanism will be complicated and large,
Unless strictness is particularly required, the image may be fixed so that it does not fall near the center of the interpupillary distance. What is J
IS. B7121 has the meaning (phenomenon or degree in which the vertical direction of the image is tilted with respect to the vertical direction of the object), but if this rotation is not performed, one line forms an angle between the left and right. It looks like you have it. The rotation angle varies depending on the width vergence angle (angle between eyepieces), the inward angle (angle between objective lenses), the interpupillary distance, and the rotation angle for adjusting the interpupillary distance. A rotation angle that will prevent the camera from falling down can be calculated or determined by experiment. For example, when the inward angle is 6 °, the convergence angle is 3.5 °, the interpupillary distance is 62 mm, and the rotation angle in the left-handed direction for adjusting the interpupillary distance is 3.5 °, the second reflecting surface 10 is moved in the right-handed direction by 5. When rotated 5 °, the fall becomes 0.

[0013] Also, although it changes alters the barrel angular inclination angle in a plane including the optical axis L ₃ of the second reflecting surface 10, it is needed as the barrel angle 45 ° to 60 ° (~ 90
°), the reflection angle α on the reflection surface 9 is 15 ° to
Assuming 25 °, the reflection angle β on the reflection surface 10 is ｛3
7.5 ° ~ 30 ° (~ 15 °)｝ ~ ｛47.5 ° ~ 40
° (〜25 °)｝. For example, FIG.
To change from 45 ° to 60 ° in FIG. 2, β ′ = β−
The angle may be set to 7.5 °.

[0014] Having described the structure and operation of the present embodiment, the present embodiment, since a structure of folding the optical path, the eye point from the specimen even in the case of a long barrel length or
The distance at is short . Moreover, since so changing the barrel angles simply by changing the inclination angle in a plane including the optical axis of the second reflecting surface 10, the height of the eye point of the optical axis L ₄ length of There is no other factor only by the change in the angle, and the change in the height is small. In addition, the roof prism is not required, the prism does not need to be changed even if the lens barrel angle is changed , and the Porro prism and two reflecting surfaces are used.
More complex arrangement than when four mirrors are combined
Since the adjustment is reduced and the frame and cover of the reflecting surface can be shared up to the first reflecting surface 9, the cost is reduced. Also, only the portion of the Porro II prism 8 expands the optical path in the horizontal direction. Since the horizontal expansion range of the optical path is small and close to the rotation axis, and the amount of protrusion when changing the interpupillary distance is small, it is compact. Can be configured.

FIG. 3 shows an optical system according to a second embodiment.
This together with the uses polo I prism 8 'instead of Porro II prism 8, exits the second reflecting surface 10 of the exit optical axis L ₃ and the second reflecting surface 10 of the first reflecting surface 9 in a plane containing Shako axis L ₄ corresponds to the angular change of the lens barrel theta those configured to change the theta / 2 angle of inclination. The rotating mechanism for that may be a known ring or a gear,
Since the number of members to be rotated is small, the configuration can be made very simply.

[0016]

As described above, in the stereo microscope according to the present invention, the distance from the specimen to the eye point is short, and the height of the eye point does not change much even when the lens barrel angle is changed.
It has an important practical advantage that it can be formed inexpensively, with a small lens barrel width, and compact.

[Brief description of the drawings]

FIGS. 1A and 1B are a side view and a front view, respectively, of an optical system of a first embodiment of a stereomicroscope according to the present invention.

FIG. 2 is a side view of the optical system when the lens barrel angle of the first embodiment is changed.

FIG. 3 is a side view of an optical system according to a second embodiment of the present invention.

FIGS. 4A, 4B, and 4C are a side view, a plan view, and a front view, respectively, of a conventional optical system.

FIG. 5 is a side view of the optical system when the lens barrel angle of the above-described conventional example is changed.

FIG. 6 is a side view of a conventional optical system.

FIG. 7 is a side view of a conventional optical system.

[Explanation of symbols]

1,2,3,4 reflecting surfaces 5,7 objective lens 6 roof prism 8 Porro II prism 8 'Porro I type prism 9 first reflective surface 10 second reflective surface _{L 1, L 2, L 3} , L 4 Optical axis O sample E eye point

Claims (2)

(57) [Claims] 1. A stereomicroscope for adjusting interpupillary distance by rotating left and right optical systems in directions opposite to each other with the optical axis of each objective lens as a rotation axis, wherein each of the optical systems includes a porro prism, and a porro prism. Deflectors the output optical axis of
A second reflecting surface, which deflects an emission optical axis of the first reflecting surface to an upper front side.
The second reflecting surface has an angle of convergence with the optical axis emitted from the first reflecting surface as a rotation axis so that the image tilt is canceled at a predetermined interpupillary distance. A stereomicroscope characterized by being arranged at a predetermined angle in a direction opposite to the direction of rotation. 2. The stereomicroscope according to claim 1, wherein the predetermined interpupillary distance is substantially near the center of the interpupillary distance adjustable range.