JPH085923A - Stereomicroscope - Google Patents

Abstract

PURPOSE:To provide a stereomicroscope capable of making an angle formed by the optical axis of an illuminating luminous flux with the optical axis of an observing luminous flux small without impairing optical performance. CONSTITUTION:A front lens for observation 12 collimating the observing luminous flux L1 from object points B1 and B2 and a lens for illumination 13 radiating the illuminating luminous flux L2 to the object point are installed to be separated. The lens 12 is constituted of a movable lens 19 reciprocated along its optical axis in order to change the positions of the object points B1 and B2 and a fixed lens 18 provided on a side faced to the object point, and the fixed lens 18 has a cutting plane notched by a plane which is parallel with a plane including both optical axes of right and left observing optical paths and nearly in contact with the right and left observing luminous flux L2, and the lens 13 is disposed proximately to the cutting plane.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to improvements in stereomicroscopes.

[0002]

2. Description of the Related Art Conventionally, US Pat. No. 4,361,37
A stereomicroscope as described in No. 9 is known. In the optical system of this stereoscopic microscope, at least a part of the front lens shared by the illumination light flux and the observation light flux can be moved along the optical axis direction to change the object point position. In this type of stereomicroscope optical system, a light-shielding plate is provided along the optical axis in order to prevent the reflected light of the illumination light beam reflected by the boundary surface between the front lens and the air from entering the observation optical path. ing.

[0003]

By the way, the movement amount of the front lens is reduced to reduce the working distance from one object point position where the observation object is arranged to another object point position where the observation object is arranged. In order to increase the amount of change, it is preferable that the front lens has two lens groups. FIG. 1 shows a schematic view of the front lens. In FIG. 1, 1 is a convex lens, 2 is a concave lens, and H1 is a convex lens 1.
, H1 'is the rear main plane of the convex lens 1, H2
Is a front main plane of the concave lens 2, H2 'is a rear main plane of the concave lens 2, d is a main plane interval between the convex lens 1 and the concave lens 2, p is a rear main plane H2' of the concave lens 2 to the object point B. Working distance.

A front lens 3 is composed of a convex lens 1 and a concave lens 2. Here, the concave lens 2 is a fixed lens, and the convex lens 1 is a movable lens.

Now, assuming that the focal length of the convex lens 1 is f1 and the focal length of the concave lens 2 is f2, the relationship between the working distance p and the principal plane distance d is expressed by the following equation.

P = {(f1-d) × f2} / (f1 + f2-d) Here, for example, the change amount of the working distance p is 160 ≦ p ≦
When the front lens 3 with 220 and the principal plane spacing d of 31 ≧ d ≧ 15 is desired, f1 and f2 are obtained based on the above equations, and f1 = 130 mm and f2 = −200 mm.

Here, the half field angle normally desired in the optical system of the stereoscopic microscope is about 8 degrees, and the relationship between the left and right observation optical paths K1 and K2 and the illumination optical path S1 is illustrated.
It becomes as shown in FIG. This FIG. 2 (a) is shown in FIG.
The section of the optical path of an optical system in position q1 of (a) is shown.

The observation light beam L1 and the illumination light beam L2 have a half angle of view of 8
The convex lens 1 is shown in FIG.
From position X1 shown in FIG. 3A to position X1 ′ shown in FIG.
Observation light flux L when moved along the optical axis between
1 and the illumination light flux L2 are designed so that the light shielding plate 4 does not cause vignetting, the illumination optical path S1
Of the observation optical paths K1, K2 from the optical axes O1 of the observation optical paths K1 and K2.
The angle θ formed by the optical axes O2 and O2 of K2 and the optical axis O1 of the illumination optical path S1 is about 7 to 8 degrees.

When observing the depth of the hole, the observation optical paths K1, K
If the angle θ between the two optical axes O2 and O2 and the optical axis O1 of the illumination optical path S1 is large, the illumination light flux L2 is blocked at the entrance of the hole, making it difficult to observe the depth of the hole.

In order to reduce the angle θ between the optical axes O2 and O2 of the observation optical paths K1 and K2 and the optical axis O1 of the illumination optical path S1,
As shown in FIG. 2 (b), the optical axis of the zoom variable power system (not shown) and the optical axis O3 of the front lens 3 are decentered to reduce the diameter of the front lens 3 for weight reduction and convex lens. However, the angle θ between the optical axes O2 and O2 of the observation optical paths K1 and K2 and the optical axis O1 of the illumination optical path S1 does not become small. Further, since the optical axes O2 and O2 of the observation optical paths K1 and K2 and the optical axis O3 of the front lens 3 are further decentered, the aberration increases, which is not desirable in optical performance.

The present invention has been made in view of the above circumstances, and the first object thereof is to reduce the angle formed between the optical axis of the illumination light beam and the optical axis of the observation light beam without impairing the optical performance. To provide a stereomicroscope.

A second object of the present invention is to provide a stereomicroscope capable of changing the illumination position by following changes in the object point position.

[0013]

A stereoscopic microscope according to claim 1 of the present application separates an observation front lens for collimating an observation light beam from an object point and an illumination lens for irradiating the object point with an illumination light beam. The observation front lens comprises a movable lens reciprocating along the optical axis for changing the position of the object point and a fixed lens provided on the side facing the object point. The lens has a cut surface that is cut by a plane that is parallel to a surface including both optical axes of the left and right observation optical paths and that is substantially in contact with the left and right observation light fluxes, and the illumination lens is disposed close to the cut surface. Has been done.

A stereoscopic microscope according to a fourth aspect of the present application is provided with an observation front lens for collimating an observation light beam from an object point and an illumination lens for irradiating the object point with an illumination light beam, and the observation lens is provided. The front lens for use is composed of a movable lens reciprocating along the optical axis for changing the position of the object point and a fixed lens provided on the side facing the object point, and is associated with the reciprocating movement of the movable lens. Illumination position changing means for changing the illumination position of the luminous flux for illumination by following the displacement of the object point position is provided.

[0015]

According to the first aspect of the invention, the object point is illuminated by the illumination lens. When the movable lens is moved along the optical axis of the observation front lens, the working distance of the optical system is changed, which changes the object point position. According to the invention of claim 4, with the movement of the movable lens,
The illumination position changing means changes the illumination position by following the displacement of the object point position.

[0016]

EXAMPLE In FIG. 4, 10 is a binocular microscope main body, and 11
Indicates an eyepiece tube. In this figure, reference numerals B1 and B2 indicate object point positions as in the conventional example, reference numeral p indicates the working distance of the optical system of the binocular microscope, and h indicates the binocular microscope. This is the amount of change in working distance. The observation target set between the object point position B1 and the object point position B2 can be seen in focus.

As shown in FIG. 5, the binocular microscope main body 10 incorporates an observation front lens 12, an illumination lens 13, a zoom variable magnification system 14, and an illumination light source section 15, and the eyepiece tube 1
1, an interpupillary adjustment prism 16 and an eyepiece lens 17 are provided. The observation front lens 12 is composed of a fixed lens 18 and a movable lens 19 which face an object point. The front lens 12 and the illumination lens 13 are separated. The observation front lens 12 and the illumination lens 13
The details of will be described later. The zoom variable power system 14 includes variable power lenses 20, 21, 22, a beam splitter 23, an imaging lens 24, and an erecting prism 25. This zoom variable power system 14 is composed of left and right optical systems, and since one optical system is provided on the other side of the drawing, it is omitted in FIG. The illumination light source unit 15 has a light source 26, a condenser lens 27, an illumination field diaphragm 28, and a reflecting prism 29 with a lens. Front lens 12, zoom variable magnification system 1
4, the interpupillary adjustment prism 16 and the eyepiece lens 17 constitute an observation optical system. For example, the observation light beam L1 emitted from the object point position B2 is collimated by the observation front lens 12 and is made to the zoom magnification system 14. Be guided. The zoom variable power system 14 is an afocal optical system, and the collimated observation light flux L1 passes through the zoom variable power system 14 and is guided to the beam splitter 23. A part of the observation light flux L1 is reflected by the beam splitter 23. TV not shown
It is guided to an image pickup device or the like to form an image. The observation light beam L1 transmitted through the beam splitter 23 forms a real image at the image point I by the imaging lens 24. The observer puts his eyes on the eye point E, and the object point position B is passed through the eyepiece lens 17.
The observation target in 2 can be observed. The interpupillary adjustment prism 16 is rotatable around its incident optical axis so that the distance between the pupils of the observer can be adjusted.

The illumination light flux emitted from the light source 26 is condensed by the condenser lens 27 and illuminates the illumination field diaphragm 28. The illumination light beam L2 that has passed through the illumination field diaphragm 28 is collimated by the lens-attached reflection prism 29 and is guided to the illumination lens 13. The focus of the illumination lens 13 is aligned with the object point position B2, the image of the illumination field diaphragm 28 is formed at the object point position B2, and the object point position B2 is uniformly illuminated. The image of the light source 26 is formed by the condenser lens 27 in the vicinity of the object point side of the illumination lens 13, that is, the exit pupil of the illumination light source unit 15 is on the object side of the fixed lens and will be described later. It is close to the cutting plane. Thereby, the illumination efficiency of the light source 26 can be improved.

A light shielding plate 30 is provided between the front lens 12 and the illumination lens 13. This light shield 3
0 plays a role of preventing the reflected light of the illumination light flux reflected by the boundary surface between the illumination lens 13 and the air from being mixed in the observation optical path. As shown in FIG. 6, the front lens 12 is a cut surface 12a which is cut by a plane which is parallel to a surface including both optical axes O2 and O2 of the left and right observation optical paths K1 and K2 and which is substantially in contact with the left and right observation luminous fluxes L1 and L1. And the illumination lens 13 has a cut surface 12a as shown in FIG. 5, FIG. 6 and FIG.
Is arranged in close proximity to. In FIG. 6, reference numeral O
Reference numeral 1 is an optical axis of the illumination optical path S1, reference numeral O3 is a front lens 1
It is the optical axis of 2. Front lens 12 and illumination lens 1
3 and the illumination lens 13 is arranged close to the cut surface 12a of the fixed lens 18, the optical axis O2 of the observation light flux L1 and the optical axis O1 of the illumination light flux L2 are separated. Since the distance can be made closer than in the conventional case, the angle formed by the optical axis O1 and the optical axis O2 can be made smaller than in the conventional case, and can be set to 5 degrees, for example.

In FIG. 5, when the movable lens 19 is displaced to the position shown by the broken line, the object point position is displaced from B2 to B1. At this time, if the illumination position by the illumination light flux L2 remains at the object point position B2, the illumination position and the object point position are displaced. In order to avoid this, the present invention is provided with an illumination position changing unit that changes the illumination position of the illumination light flux L2 by following the displacement of the object point position due to the reciprocating movement of the movable lens 19.

8 to 10 are explanatory views of the illumination position changing means, and in FIGS. 8 and 9, reference numerals 31 and 32 are lens holders. Guide pins 33, 33 are provided on the lens holder 31 so as to project therefrom. The lens holder 32 is guided by the guide pin 33 and moved up and down. Lens holder 3
A lens 13 for illumination and a fixed lens 18 are held at 1. The lens holder 32 holds the movable lens 19. A pair of support plates 34 are attached to the lens holder 31 as shown in FIG.
Rotational support pins 35 are attached to a and 34.
A holding frame 36 is rotatably supported by the rotation support pin 35. Both sides of the reflection prism with lens 29 are adhered to both side plates 36 a and 36 a ′ of the holding frame 36 and held by the holding frame 36. A support pin 37 is attached to the upper end of the side surface 36a ', and a roller 38 is rotatably supported on the support pin 37.

The light shield plate 30 is a cut surface 12 of the fixed lens 18.
It is adhered to a and fixed to the lens holder 31. As shown in FIG. 9, a rack plate 39 is fixed to the lens holder 32 with a screw 39C. Rack teeth 39a and sliding contact surfaces 39b are formed on the rack plate 39 as shown in FIG. A pinion 40 is meshed with the rack tooth 39a. This pinion 40 is a motor (not shown)
Is attached to the output shaft 41 of the. The roller 38 is in sliding contact with the sliding surface 39b. The sliding contact surface 39b is configured to incline with respect to the vertical line, and the holding frame 36 is the
8 is constantly urged by a torsion coil spring (not shown) in a direction in which the sliding contact surface 39b is in sliding contact with the sliding contact surface 39b. Lens holder 3
2 is reciprocated in the optical axis direction of the front lens 12 by a motor, a pinion 40, and a rack plate 39.

When the movable lens 19 is moved to the position indicated by the broken line as shown in FIG. 5, the object point position is displaced from B2 to B1. At the same time, the lens-equipped reflection prism 29 is rotated in the direction of the arrow X about the support pin 35, and the reflection surface 29a of the lens-equipped reflection prism 29 is rotated to the position indicated by the broken line, so that the movable lens 19 reciprocates. Along with the displacement of the object point position, the illumination position of the illumination light flux L2 is changed to the object point position B1 as shown by the broken line, and the illumination center can be changed to follow the displacement of the object point position.

Further, according to this embodiment, since the diameter of the front lens 12 can be made small, the weight of the front lens 12 can be reduced.

FIG. 11 shows a modified example of the illumination position changing means. In this modified example, instead of rotatively displacing the reflection prism with lens 29, the vertical angle is provided between the reflection prism with lens 29 and the illumination field diaphragm 28. Declination prism 42 with
43 is provided, and the declination prisms 42 and 43 are arranged at the reference object point position B2 as shown in FIG. 11 so as to function as a plane-parallel plate having no declination as a whole.
Following the displacement of the object point position (that is, the movable lens 19
A pair of declination prisms 42 and 43 are rotated in opposite directions to deviate the optical axis of the illumination optical path,
The illumination center is changed by following the displacement of the object point position. In FIG. 11, the deflection angle prism 4
For convenience of explanation, reference numerals 2 and 43 are drawn by rotating them by 90 degrees around the optical axis of the illumination optical path.

[0026]

According to the invention described in claim 1 of the present application,
An observation front lens for collimating the observation light flux from the object point and an illumination lens for irradiating the object light beam with the illumination light flux are separately provided, and the observation front lens is arranged along the optical axis to change the object point position. It is composed of a movable lens that is reciprocally moved and a fixed lens that is provided on the side facing the object point. Since the illumination lens is provided in the vicinity of the cut surface with the cut surface cut out, the angle formed between the optical axis of the observation optical path and the optical axis of the illumination optical path can be made smaller than before, Therefore, the depth of the hole and the concave portion of the object having large unevenness can be satisfactorily illuminated, and the object having large unevenness can be easily observed without impairing the optical performance.

According to the invention of claim 4 of the present application, in the case where the observation front lens for collimating the observation light beam from the object point and the illumination lens for irradiating the object light beam with the illumination light beam are separated from each other, Even if there is, there is an effect that the illumination position can be matched with the object point position.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a configuration of a conventional front lens.

2 is an optical path sectional view for explaining a conventional defect, FIG. 2 (a) is an optical path sectional view of an optical system at a position q1 in FIG. 3 (a), and FIG. FIG. 6 is an optical path cross-sectional view for explaining a problem when the optical axis of the zoom variable power system and the optical axis of the front lens are decentered.

FIG. 3 is a schematic diagram of an optical system for explaining a conventional defect, and FIG. 3A shows a relationship between an observation light flux and an illumination light flux when the front lens is at a reference position. Three
(B) shows the relationship between the observation light flux and the illumination light flux when the front lens is moved.

FIG. 4 is an external view of a stereoscopic microscope according to the present invention.

FIG. 5 is an optical diagram of a stereomicroscope according to the present invention.

6 is an optical path cross-sectional view of an observation light flux and an illumination light flux according to the present invention at reference numeral q2 in FIG. 7.

FIG. 7 is a schematic diagram of an optical system for explaining the present invention.

FIG. 8 is a plan view for explaining a drive unit of the illumination position changing unit.

FIG. 9 is a side view for explaining a drive unit of the illumination position changing unit.

FIG. 10 is a rear view for explaining a drive unit of the illumination position changing unit.

FIG. 11 is an optical diagram for explaining a modified example of the illumination position changing means.

[Explanation of symbols]

 Reference numeral 12 ... Observation front lens 12a ... Cut surface 13 ... Illumination lens 15 ... Illumination light source part 18 ... Fixed lens 19 ... Movable lens 19 30 ... Shading plate B1, B2 ... Object point position L1 ... Observation luminous flux

Claims (4)

[Claims] 1. An observation front lens for collimating an observation light beam from an object point and an illumination lens for irradiating the object light beam with an illumination light beam are separately provided, and the observation front lens changes an object point position. In order to reciprocate along the optical axis, a movable lens and a fixed lens provided on the side facing the object point are provided, and the fixed lens is parallel to a surface including both optical axes of the left and right observation optical paths. A stereomicroscope that has a cut surface cut out by a plane that is substantially in contact with the left and right observation light beams, and the illumination lens is arranged in the vicinity of the cut surface. 2. The stereomicroscope according to claim 1, wherein the exit pupil of the light source unit is provided on the object side of the fixed lens and close to the cut surface. 3. The light shielding plate for preventing the reflected light flux of the illumination light flux from the illumination lens from mixing in the observation optical path is provided along the cut surface. Stereo microscope. 4. An observation front lens for collimating an observation light beam from an object point and an illumination lens for irradiating the object light beam with an illumination light beam are separately provided, and the observation front lens changes an object point position. In order to reciprocate along the optical axis of the movable lens and a fixed lens provided on the side facing the object point, the movable lens follows the displacement of the object point position associated with the reciprocal movement of the movable lens. A stereoscopic microscope provided with an illumination position changing means for changing the illumination position of a light flux for illumination.