JP2001311876A - Stereo-microscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stereo-microscope by which a stereoscopic effect is prevented from getting different even when the angle of convergence is different between respective testers and whose assembly adjustment is facilitated even in the case of structure obtaining the same stereoscopic effect. SOLUTION: In this stereo-microscope, 1st and 2nd erect prisms 24 and 24' and image-formation lenses 23 and 23' are used as a pupil distance adjusting means for preventing the stereoscopic effect from being changed even when a pupil distance L formed by 1st and 2nd eyepieces 25 and 25' is changed, and a condition that the pupil distance adjusting means keeps the angle of convergence θformed by the eyepieces 25 and 25' the same even when the pupil distance L formed by the eyepieces 25 and 25' is changed and a light beam advancing along the optical axes Oa3 and Oa3' thereon are made to advance along the optical axis Oa4 of each eyepiece system is maintained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical configuration of a binocular stereomicroscope, and more particularly to an optical configuration of a slit lamp binocular stereomicroscope used in the field of ophthalmology.

[0002]

2. Description of the Related Art In general, binocular stereomicroscopes are roughly classified into a Grinot-type and a Galileo-type. <Grenault-type Binocular Microscope> As shown in FIG. 4, the Grinow-type binocular microscope is configured such that two optical paths I and II intersect with each other at a narrow angle ω (stereo angle) on the surface of the test object. These optical paths I and II are respectively connected to the objective lens systems 1a and 1
b, erecting optical systems 2a and 2b, and eyepiece systems 3a and 3
b is provided. Further, assuming that the incident optical axes IA and IB to the objective lenses 1a and 1b, the included angle θ of the incident optical axes IA and IB is equal to the convergence angle. Since the stereo angle ω is configured to be substantially equal to the convergence angle in the natural vision state, that is, the included angle θ between the incident optical axes IA and IB, there is an advantage that natural stereoscopic vision is possible.

[0003] However, in the Greeneau type, the optical paths I,
Since the angle II is oblique, it must be complicated mechanically and the assembly and adjustment of the variable power optical system must be difficult. <Galileo Binocular Microscope> Galileo binocular microscopes include a type having a convergence angle of 0 degree and a type having a convergence angle. Note that two types of Galileo microscopes having a convergence angle are known. (Galileo Binocular Microscope with 0 ° Convergence Angle) The Galileo binocular microscope with 0 ° convergence angle has optical paths III and IV to the eye E as shown in FIG.

The optical path III includes an objective lens system 4, an imaging lens system 7a for forming an intermediate image Pa, and an erecting optical system 5
a and an eyepiece system 6a for observing the intermediate image Pa
It is composed of The optical path IV has the objective lens system 4 as a common objective lens, and includes an imaging lens system 7b, an erecting optical system 5b, and an eyepiece lens system 6b as in the optical path III.

Here, the optical axes of the two imaging lens systems 7a and 7b are parallel to each other and also to the optical axis 4a of the objective lens system 4. Further, the stereo angle ω formed by the observation optical axes IIIA and IVB of the eyepiece systems 6a and 6b is determined by the objective lens 4.

In this Galileo binocular microscope, since the parallax has such a stereo angle ω, the observation optical axis I
Even when the convergence angle θ formed by IIB and IVB is 0 degree, the subject E can be stereoscopically viewed.

Moreover, in the Galileo binocular microscope, since the two optical paths III and IV are parallel to each other as described above, the configuration of the optical system can be simplified. Further, the Galileo binocular microscope has an advantage that an additional optical path such as a photographing optical system and a side endoscope can be easily added.

By the way, in general, the human eye is in the most comfortable and less fatigued observation state in which there is no vergence angle in the binocular gaze and the lens is not adjusted in the far vision state. The same is true for microscopic observation, and the Galileo microscope in which both observation optical axes IIIB and IVB are parallel to each other in FIG. 5 has less fatigue during observation and a longer time than that of a Greenwich microscope in which both are congested. It is said that it is advantageous for observation.

However, a microscope is a device for magnifying and observing an object placed at a short distance. In a Galileo microscope, even if a light beam from an infinite distance optically enters the eye, it is close to the brain. There is premise information that looks at an object at a distance, and there is a drawback that a difference is made between this and natural sensation.

[0010] This is because the parallax due to the stereo angle ω is observed even though there is no information about the rotational movement of the eye, that is, the information about the convergence movement. There was a drawback that stereoscopic vision was forced.

Further, taking the case of a slit lamp used in the field of ophthalmology as an example, the doctor adjusts the irradiation position of the slit illumination light to the subject, the slit width, the length of the slit, or the like. It is often necessary to check the eye to be examined with the naked eye for a simple surgical procedure on a patient. In addition, at the time of this confirmation, the observation eye of the doctor is in a near vision state.

Then, the eyes must be diverged to a far-sighted state where there is no radiation when looking through the microscope, and stereoscopic viewing is required. (Galileo Binocular Microscope with Vergence Angle Not 0 °) On the other hand, FIG. 6 shows a Galileo type with a vergence angle θ not being 0 °. The Galileo binocular microscope has optical paths 100 and 200.
The optical path 100 includes an objective lens system 101 and an intermediate image 10.
And an imaging lens system 10 having an optical axis parallel to the optical axis 101a of the objective lens system 101.
3. It is composed of a deformed Porro prism 104 as an erecting optical system, which is an optical path deflecting means, and an eyepiece lens system 105 for observing the intermediate image 102.

On the other hand, an optical path 200 is an objective lens system 101 common to the optical path 100, a lens for forming an intermediate image 202, and an imaging lens having its optical axis parallel to the optical axis 101a of the objective lens system 101. System 203, modified Porro prism 20 as optical path deflecting means and as an erecting optical system
4 and an eyepiece system 2 for observing the intermediate image 202
05.

Here, the apex angle α of each of the prisms 106 and 206 constituting the modified Porro prisms 104 and 204 has a magnitude of (90 ° −ω / 4). ω is a stereo angle formed between the incident optical axis 100A of the optical path 100 to the test object E and the incident optical axis 200A of the optical path 200, and the magnitude thereof is a base line length Lb between the two imaging lenses 103 and 203.
Is determined by

By the way, the three-dimensional effect of the observer is described in Japanese Patent Application No.
9054, it greatly depends on the convergence angle θ. For both the Galileo type and the Greeneau type, the three-dimensional effect increases as the convergence angle θ decreases, and in both types, when the stereo angle ω and the convergence angle θ are equal, a natural three-dimensional effect similar to the naked eye can be obtained. Proven.

In the Galileo microscope in which the convergence angle is not 0 degree, the optical axes of the imaging lenses 103 and 203 are kept parallel to each other. The optical system (the imaging lens may also serve as this) and their driving mechanisms are simpler than those of the Greenau type.

A Galileo microscope having a convergence angle other than 0 degree has an advantage of a Galileo-type binocular stereo microscope in which an attached optical system such as an imaging optical system can be easily incorporated, and a natural similar to that of the naked eye observation. This is an improved Galileo-type binocular stereomicroscope that combines the advantages of the Grinot-type that enables microscopic observation with a three-dimensional effect.

However, depending on the distance PD between the pupils of the observer, the viewing angle is downward or upward and the viewing angle in the left-right direction changes. That is, the convergence angle θ is defined when the interpupillary distance PD is the widest, and when it is smaller than that, the so-called convergence angle θ decreases because the viewing angle is downward.

Further, details of the Galileo microscope will be described. FIG. 7 shows the arrangement of the optical system on the left side of the eyepiece section of this microscope, in which the interpupillary distance PD is at a maximum.
0 is the center of the machine, 11 is the optical axis and also the rotation axis. While the parallel light flux converges on the imaging lens 12, the triangular prisms 13, 1
4, the light is deflected upward with respect to the paper surface by the right-angled triangular prism 15, and further deflected toward the examiner, so that an intermediate image is formed on the field stop 15. The eye point 18 is a position where the image can be magnified by the eyepiece 16 and the entire field of view can be seen without vignetting. Let b be the length of the perpendicular from the eye point 18 to the optical axis 11. The interpupillary distance PD is changed by rotating the triangular prisms 13, 14, 15, the field stop 16, and the eyepiece 17 about the optical axis 11. FIG.
The left optical system is the same as in FIG. 7, and shows a change in the deflection angle of the optical axis. A circle A with a radius r on the xy plane where the eye point moves with OO 'as a rotation axis, and a circle B with a radius a on the x'y' plane that extends the emission optical axis and intersects and is perpendicular to the optical axis 11
Put. When the RP is rotated by β, the circle A moves from the point P to the point Q and the circle B moves from the point R to the point S, and the y component of the declination becomes the lower viewing angle θ1 and the x component becomes the inner viewing angle θ2.

The equation of the circle A is: y = r sin (α + β) x = r cos (α + β) (1) The equation of the circle B is y ′ = a cos β x ′ = − a sin β From the triangular PTR k = b / tan θ / 2 From the geometric relationship of the circle A, a = arc tan a / b

If the interpupillary distance PD is given as the base line length of 22 mm, the rotation angle β is obtained from the following equation: PD = 2 (x + 11) ∴X = PD / 2-11

Β = arc cos (x / r) −a = arc cos [(PD / 2-11) / r] −α At this time, the lower viewing angle · 1 and the inner viewing angle · 2 are as follows.

Θ1 = arc tan [(yy ′) / k] θ2 = arc tan [(xx ′) / k] And another improved Galilean binocular stereo microscope shown in FIG. Uses the refraction of the prism. A polarizing prism 102 for forming a convergence angle θ between the objective lens 101 and the imaging lens 103 in the first optical path 100 is similarly provided between the objective lens 101 and the imaging lens 203 in the second optical path 200. The convergence angle θ is obtained by arranging the deflecting prisms 202 for forming. Therefore, in the Galileo binocular stereomicroscope, the convergence angle does not change due to the change in the interpupillary distance PD.

However, considering the optical adjustment, the polarizing prism 10
2 and the optical axis of the imaging lens 103 are adjusted, and the optical axes of the deflecting prism 202 and the imaging lens 203 are adjusted in the same manner, so that the absolute amount of the angular error of the left and right optical systems and the relative amount The volume (especially the height) must be controlled. From the above, the assembly process is not always easy.

[0025]

In such a Galileo binocular stereomicroscope, different examiners have different convergence angles resulting in different stereoscopic effects, and assembly and adjustment are required even if the structure is such that the same stereoscopic effect can be obtained. It had the disadvantage of not being easy.

Therefore, the present invention has been made to satisfy the above-mentioned drawbacks of the conventional stereoscopic microscope, and the three-dimensional appearance does not change even if the convergence angle differs depending on each examiner. It is another object of the present invention to provide a binocular stereo microscope that can be easily assembled and adjusted even in a structure that can provide the same three-dimensional effect.

[0027]

In order to achieve this object, an object of the present invention is to provide an objective optical system for producing first and second intermediate images of a test object, and an objective optical system for producing the first and second intermediate images. First and second eyepiece lens systems for observing each of the intermediate images, and first and second erecting optical systems for the intermediate images to be erect images. Binocular stereomicroscopes respectively disposed in front of the eyepiece lens system, wherein the interpupillary distance adjusting means which does not change the stereoscopic effect even if the interpupillary distance PD made by the first and second eyepiece systems is changed. The first and second erecting optical systems and the imaging lens system are used, and the interpupillary distance adjusting means includes an interpupillary distance PD formed by the first and second eyepiece systems.
Even if is changed, the convergence angle created by the first and second eyepiece systems is kept the same, and light rays traveling along this optical axis on the optical axis along the optical axis of each eyepiece system The binocular stereomicroscope is characterized in that the condition for advancement is maintained.

According to a second aspect of the present invention, the objective optical system has one common objective lens system and an optical axis parallel to the optical axis of the objective lens system, and the first and second imaging lens systems And characterized in that:

Further, in order to achieve the above-mentioned object, the invention according to claim 3 provides an objective optical system having one objective lens for forming first and second intermediate images of a test object, An optical axis including an eyepiece lens system, a second eyepiece lens system, and first and second erecting optical systems provided between the eyepiece lens systems and the objective lens, and passing through an optical center of the objective lens. An upright having a deflecting function of forming a convergence angle on the optical axes of the first and second eyepiece systems after deflecting a pair of optical paths defined along an optical axis parallel to The binocular stereo microscope is characterized in that the prism is the erecting optical system so that the visual axis of the examiner coincides with the optical axis passing through the optical center of each eyepiece.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings showing an embodiment. [Configuration] FIG. 1 shows an arrangement of a slit lamp optical system in a binocular stereo microscope according to the present invention. In FIG.
E is the subject's eye, e1 is the examiner's right eye (examiner's eye), e
Reference numeral 2 denotes an examiner's left eye (examiner's eye).

The binocular stereo microscope of FIG. 1 has first and second observation optical systems 20 and 21. <First observation optical system 20> This first observation optical system 20
Has an objective lens 22, an imaging lens 23, an erect prism (erect optical system) 24, and an eyepiece 25. 22a
Is the optical axis of the objective lens 22, which is also the optical axis of the slit lamp. The erecting prism (erecting optical system, modified Porro prism) 24 includes triangular prisms 26 and 27 and a right-angled triangular prism 28.

The first observation optical system 20 includes a convergence optical axis Oa1 from the eye E to the objective lens 22 and a lens optical axis of the imaging lens 22 (from the objective lens 22 to the triangular prism 2).
6, an optical axis Oa3 located between the triangular prisms 26 and 27 and extending slightly inclining with respect to the lens optical axis Oa2 and extending in a direction intersecting therewith, and slightly inclining with respect to the optical axis Oa3. And a convergence optical axis Oa4 (the optical axis of the eyepiece lens 25 and the optical axis extending from the triangular prism 28 to the right eye e1) extending in the direction of intersection.

The triangular prism 27 can be moved relative to the triangular prism 26 in the direction in which the optical axis Oa3 extends, and the right-angle triangular prism 28 and the eyepiece 25 can be moved integrally with the triangular prism 27. Has become. Moreover, the triangular prism 27 is the triangular prism 2
In order to prevent the image formation point F by the image formation lens 25 from shifting when the movement of the image formation lens F is adjusted toward or away from the optical axis Oa3 with respect to the direction in which the optical axis Oa3 extends, the image formation lens 23 has a triangular prism 26.
The imaging lens 23 and the triangular prism 2 are adjusted so as to move away from and approach in the direction in which the lens optical axis Oa2 extends.
7 are linked. <Second observation optical system 21>
Has an objective lens 22 common to the first observation optical system 20. In addition, the second observation optical system 21 has the same optical components (optical members) as the imaging lens 23, the erect prism (erect optical system) 24, and the eyepiece 25 of the first observation optical system 20. The same optical components are denoted by the same reference numerals used in the first observation optical system 20 with "'" appended thereto, and description thereof is omitted. <Other Configurations> Further, the optical axes Oa2 and Oa2 'of the imaging lenses 23 and 23' are provided in parallel with the optical axis 22a of the objective lens 22. Also, the convergence optical axes Oa1, Oa1 '
Assuming that the angle of convergence between is ω, the angle of convergence between the convergence optical axes Oa4 and Oa4 ′ is θ, and the apex angle when the triangular prisms 26 and 27 are combined is α, the apex angle α is (90 ° + θ / 4). Is set. The pupil distance L of a normal slit lamp is 5
It is about 5 mm to 80 mm.

Further, the angle between the optical axes Oa2 and Oa3 is shown in FIG.
(90 ° −θ / 4) as shown in FIG.
Further, if the surface of the triangular prism 27 facing the triangular prism 26 is a first surface 27a, and the surface of the triangular prism 27 facing the right-angle triangular prism 28 is a second surface 27b, the first and second surfaces Is set to (90 ° + θ / 4). With such a setting, the optical axis Oa4 is inclined by θ / 2 with respect to the optical axis Oa2. [Operation] Next, the operation of the binocular stereomicroscope having such a configuration will be described. <Adjustment between pupils> (Increase in distance between pupils) FIGS. 1 and 3A show the distance L between pupils.
Is the minimum Lmin state. In order to increase the distance between pupils as shown in FIGS. 2 and 3B, the triangular prisms 27 and 28 of the erecting prism 24 are moved along the optical axis as shown in FIG. In the direction in which Oa3 extends (the optical axis direction) and the triangular prism 2
6 in the direction away from the triangular prism 26 'by the distance d and the triangular prisms 27' and 28 'of the erecting prism 24' in the direction in which the optical axis Oa3 'extends (optical axis direction) and by the distance d from the triangular prism 26'. In the direction you want.

At this time, in conjunction with the movement of the triangular prisms 27 and 28 of the erecting prism 24, the imaging lens 23 moves
Only in the direction in which the lens optical axis Oa2 extends (the optical axis direction) and toward the triangular prism 26, and the erecting prism 2
In conjunction with the movement of the 4 'triangular prisms 27' and 28 ',
The imaging lens 23 'moves toward the triangular prism 26' by the distance d in the direction in which the lens optical axis Oa2 'extends (the optical axis direction).

Then, the distance L between pupils becomes [Lmin + 2dcos (θ / 4)] by such a movement. (Reduction of Interpupillary Distance) In order to reduce the interpupillary distance, the triangular prisms 27 and 28 of the erecting prism 24 are connected to the optical axis Oa3.
In the direction of extension of the optical axis (the direction of the optical axis) and in a direction approaching the triangular prism 26 by a distance d, and the triangular prisms 27 'and 28' of the erecting prism 24 'are moved along the optical axis Oa3'.
In the direction in which the triangle prism 26 'extends (the direction of the optical axis) and in a direction approaching the triangular prism 26' by a distance d.

At this time, in conjunction with the movement of the triangular prisms 27 and 28 of the erecting prism 24, the imaging lens 23 moves the distance d.
Only in the direction in which the lens optical axis Oa2 extends (the optical axis direction) and in the direction away from the triangular prism 26,
In conjunction with the movement of the triangular prisms 27 'and 28' of the erecting prism 24 ', the imaging lens 23' moves away from the triangular prism 26 'by the distance d in the direction in which the lens optical axis Oa2' extends (optical axis direction). Move in the direction you want.

Thus, the triangular prisms 27, 27 '
Are optical axes Oa3, Oa with respect to the triangular prisms 26, 26 '.
When the movement is adjusted in the approaching / separating direction in the extending direction of 3 ', the imaging points F and F' by the imaging lenses 23 and 23 'do not shift.

Furthermore, even if the interpupillary distance L is increased or decreased as described above, the optical axes Oa2 and Oa
The distance (base line length) Lb between 2 'is the same without change,
In addition, since the convergence angle θ and the stereo angle ω are always the same without change, the stereoscopic effect does not change.

As described above, in the binocular stereo microscope described above,
An objective lens (objective optical system) 22 for forming first and second intermediate images of the test object at the imaging points F and F ', and a second lens for observing the first and second intermediate images, respectively. It has first and second eyepieces (first and second eyepieces) 25 and 25 ', and first and second erecting prisms (erecting optical system) for turning an intermediate image into an erect image. 24, 24 'are arranged in front of first and second eyepieces (first and second eyepiece systems) 25, 25', respectively. Moreover, in this binocular stereo microscope, the first and second
2 eyepieces (first and second eyepiece systems) 25, 2
Even if the interpupillary distance L formed by 5 'is changed, the first and second erect prisms (erect optical systems) 24 and 24' and an imaging lens (imaging lens) are used as an interpupillary distance adjusting means which does not change the stereoscopic effect. In addition to using the image lens systems) 23 and 23 ', the interpupillary distance adjusting means changes the interpupillary distance L formed by the first and second eyepieces (first and second eyepiece systems) 25 and 25'. Even second
1 and 2 eyepieces (first and second eyepiece systems) 2
5, 25 ', while maintaining the same convergence angle [theta], the light rays traveling along these optical axes on the optical axes Oa3, Oa3' are advanced along the optical axis Oa4 of each eyepiece lens system. Has been maintained.

In the binocular stereomicroscope, the objective optical system has one common objective lens (objective lens system) 22 and optical axes Oa2 and Oa2 'parallel to the optical axis 22a of the objective lens (objective lens system) 22. And first and second imaging lenses (first and second imaging lens systems) 23 and 23 ′.

Further, in this binocular stereomicroscope, an objective optical system having one objective lens 22 for producing first and second intermediate images of the test object, and first and second eyepieces ( First and second eyepiece systems) 25 and 25 'and the first and second eyepieces (first and second eyepiece systems) 25 and 25'.
And first and second erect prisms (erect optical systems) 24 and 24 ′ provided between the first and second objective lenses 22.
In this binocular stereo microscope, the optical axes Oa2 and Oa parallel to the optical axis 22a passing through the optical center of the objective lens 22 are provided.
After deflecting a pair of optical paths defined along 2 ′ outwardly, the convergence angle θ of the first and second eyepieces (first and second eyepiece systems) 25 and 25 ′ By using the erecting prisms 24 and 24 'having a deflecting function to form an erecting optical system, the visual axis of the examiner and each eyepiece 2
The optical axes Oa4 and Oa4 'passing through the optical centers of 5, 25' coincide with each other.

[0043]

As described above, claims 1, 2, 3
According to the binocular stereo microscope described in (1), the distance between pupils can be adjusted while maintaining the stereoscopic effect at the time of observation under the microscope without deteriorating the observation image while having the advantages of the Galileo stereo microscope.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of an optical system of a binocular stereo microscope according to the present invention.

FIG. 2 is an explanatory diagram of an operation of the optical system of FIG. 1;

FIG. 3 is a partially enlarged explanatory view of FIG. 2;

FIG. 4 is an explanatory diagram showing an example of an optical system of a conventional binocular stereo microscope.

FIG. 5 is an explanatory diagram showing another example of an optical system of a conventional binocular stereo microscope.

FIG. 6 is an explanatory diagram showing another example of the optical system of the conventional binocular stereo microscope.

FIG. 7 is an explanatory diagram showing another example of an optical system of a conventional binocular stereo microscope.

FIG. 8 is an explanatory diagram showing another example of the optical system of the conventional binocular stereo microscope.

FIG. 9 is an explanatory diagram showing another example of the optical system of the conventional binocular stereo microscope.

[Explanation of symbols]

F, F 'imaging point 22: objective lens (objective optical system) 22a: optical axis 23, 23': imaging lens (imaging lens system) 24, 24 ': erect prism (Erect optical system) 25, 25 '... eyepiece (first and second eyepieces) L ... distance between pupils θ ... convergence angle Oa3, Oa3' ... optical axis

Claims (3)

[Claims] An objective optical system for producing first and second intermediate images of a test object, and first and second eyepieces for observing each of the first and second intermediate images. A first and a second erecting optical system for converting the intermediate image into an erect image.
Binocular stereomicroscopes respectively disposed in front of the eyepiece lens system, wherein the interpupillary distance adjusting means which does not change the stereoscopic effect even if the interpupillary distance PD made by the first and second eyepiece systems is changed. The first and second erecting optical systems and the imaging lens system are used, and the interpupillary distance adjusting means includes the first and second erecting optical systems.
Even if the interpupillary distance PD created by the second eyepiece system is changed, the convergence angle created by the first and second eyepiece systems is kept the same, and along the optical axis on the optical axis. A binocular stereomicroscope characterized in that the condition that advancing light rays are advanced along the optical axis of each eyepiece lens system is maintained. 2. An objective optical system according to claim 1, wherein the objective optical system has one common objective lens system and an optical axis parallel to an optical axis of the objective lens system, and includes first and second imaging lens systems. Claims characterized
2. The binocular stereomicroscope according to 1. 3. An objective optical system having one objective lens for forming first and second intermediate images of a test object, first and second eyepiece systems, and each of the eyepiece systems. And a pair of optical paths defined along an optical axis parallel to an optical axis passing through the optical center of the objective lens and having first and second erecting optical systems provided between the optical system and the objective lens. After deflecting outwardly to each other, the erecting optical system uses an erecting prism having a deflecting function to form a convergence angle on the optical axis of the first and second eyepiece lens systems. A binocular stereomicroscope characterized in that the visual axis of the eyepiece and the optical axis passing through the optical center of each eyepiece coincide with each other.