JP2011150190A - Microscope lens barrel and microscope with the lens barrel - Google Patents

Abstract

An object of the present invention is to provide a lens barrel capable of blocking the left and right optical paths even if it has a movable mechanism inside.
A lens barrel main body and a light beam that is provided on the lens barrel main body, is emitted from an object and passes through an objective lens and a pair of independent variable magnification optical systems, and forms an image of the object. A pair of independent second objective lenses to be imaged, a movable part rotatably supported by the lens barrel main body part, and provided at the movable part. A pair of independent binocular portions that are variable and a pair of binocular portions that rotate in conjunction with the rotation of the movable portion, and the parallel light beams emitted from the pair of second objective lenses are respectively applied to the pair of binocular portions. A deflecting optical unit for guiding, and a light shielding member provided in the deflecting optical unit, which shields each optical path of the parallel light flux between the pair of second objective lenses and the pair of binocular units. A lens barrel characterized by comprising.
[Selection] Figure 3

Description

  The present invention relates to a stereomicroscope.

  When observing an object with unevenness, the stereomicroscope can observe the object with a three-dimensional effect in the same way as when viewed with the naked eye. For this reason, when working under a microscope, it is possible to easily grasp the distance relationship between a tool such as tweezers and an object. Therefore, it is particularly effective in fields requiring fine treatment such as precision machine industry, biological dissection, and surgery.

  A typical method for obtaining a stereoscopic view is to use a parallel stereo microscope (parallel single objective binocular microscope). The parallel system stereomicroscope has one objective lens system and two observation optical systems for the left eye and for the right eye arranged in parallel to the optical axis of the objective lens system. The observation optical system includes a variable magnification optical system for changing the magnification of an observation image of an object, and an eyepiece lens system for observing an image emitted from the variable magnification optical system.

  In the parallel system stereomicroscope, one objective lens whose focal point coincides with the object plane plays a role of guiding a parallel light beam to the subsequent variable magnification optical system for the left eye and the right eye. The parallel light beam emitted from the objective lens is divided into two variable power optical systems and individually guided to the left and right eyes. In the parallel system stereomicroscope, the light beam emitted from the variable magnification optical system is a parallel light beam. Therefore, an illuminating device or the like is disposed between the variable magnification optical system and the lens barrel so that observation can be performed by various observation methods. However, with the diversification of observation methods and the enlargement of the zooming range, the imaging position of the light beam from the object has become high. For this reason, an inclination lens barrel in which the height of the imaging position and the deflection direction are variable is used so that the observer can observe in a comfortable posture for a long time. In the tilt lens barrel, the imaging position is changed by moving an optical element such as a mirror or a prism.

FIG. 11 is an enlarged view showing a part of the object side of the objective lens 307 and the variable magnification optical system 119. As shown in FIG. 11, the numerical aperture of the objective lens 307 in the stereomicroscope is such that the light emitted from the object point S on the optical axis L of the objective lens 307 is incident on the optical axis L ′ of the variable magnification optical system 119. , Defined by the sine (sinβ) of the angle β formed by the light emitted from the object point S on the optical axis L of the objective lens 307 and the light beam entering the outermost side of the objective lens 307. The light emitted from the object point S on the optical axis L of the objective lens 307 enters the objective lens 307 to become a parallel light beam and enters the variable magnification optical system 119. Since the objective lens 307 sufficiently satisfies the sine condition, the diameter of the parallel light flux is twice the product of the focal length fobj of the objective lens 307 and the sine of β (2 × fobj × sinβ). In order for the objective lens 307 to exhibit the performance corresponding to the numerical aperture, all the parallel light beams need to be guided to the variable magnification optical system 119. That is, when the effective diameter of the variable magnification optical system 119 is Dep, Dep needs to satisfy the following equation (1).
Dep ≧ Diameter of parallel beam (= 2 × fobj × sinβ) (1)
From the equation (1), the numerical aperture of the objective lens in the stereomicroscope depends on the effective diameter Dep of the variable magnification optical system. Increasing the effective diameter Dep of the variable magnification optical system means increasing the distance between the optical axes of the two variable magnification optical systems. That is, it can be said that the numerical aperture of the stereomicroscope is determined by the distance between the optical axes of the variable magnification optical system.

  In order to improve the resolution of the parallel stereomicroscope, it is necessary to increase the effective diameter Dep of the variable magnification optical system. However, if the effective diameter Dep is increased, the distance between the left and right optical axes increases, and the apparatus becomes larger. In order to minimize the increase in size of the apparatus, it is necessary to make the left and right optical paths close to each other. However, if the left and right optical paths are brought close to each other, stray light generated in each of the left and right optical paths may enter the adjacent optical path and cause flare, resulting in a decrease in contrast. In Patent Document 1, in order to prevent a decrease in contrast due to flare, a light shielding member is provided between the left and right optical paths in the variable magnification optical system.

Japanese Patent No. 3772004

  In the parallel system stereomicroscope, the lenses on the left and right optical paths located closest to the object side of the variable magnification optical system are in contact with each other or juxtaposed with a very short interval. For this reason, when the light shielding member is disposed between the left and right optical paths of the variable magnification optical system as in Patent Document 1, there is a problem that the effective diameter of the lens is reduced.

  In addition, in the tilt lens barrel, the image position is changed by moving an optical element such as a mirror or a prism, but the mechanical mechanism for moving these optical elements is complex and has a large number of parts. Stray light is generated when light unnecessary for image formation is reflected and scattered by optical elements and mechanical mechanisms, and therefore tends to increase as the mechanical mechanism inside the lens barrel becomes complicated.

  The stray light generated in the variable magnification optical system passes through the optical element and mechanical mechanism of the variable magnification optical system, and further, the optical element and mechanical mechanism of the tilt lens barrel before reaching the eyes of the observer. For this reason, the influence on observation is very small by being dimmed or diffused by the transmittance and reflectance of these optical elements and mechanical mechanisms. On the other hand, the stray light generated in the tilt lens barrel is close to the observer's eyes, so it does not pass through the optical element at all, or only passes through the optical element and mechanical mechanism of the tilt lens barrel, so that it is sufficiently dimmed or diffused. It reaches the eyes of the observer without being done. For this reason, the influence on observation becomes large. Therefore, in order to reduce unnecessary light, it is effective to block the left and right optical paths of the tilt lens barrel. However, since the inside of the tilt lens barrel has a movable mechanism, it is difficult to shield the light.

  The present invention has been made in view of such circumstances, and it is an object of the present invention to provide a lens barrel that can shield the left and right optical paths even if it has a movable mechanism inside.

  The lens barrel according to the present invention includes a lens barrel main body, and a light beam that is provided on the lens barrel main body and is transmitted from the object and passes through the objective lens and a pair of independent variable power optical systems. A pair of independent second objective lenses that form an image of the image, a movable part rotatably supported by the barrel main body, and a movable part that is provided on the movable part and rotates together with the movable part. And a pair of independent binocular portions whose tilt angles are variable, and a pair of binocular portions that rotate in conjunction with the rotation of the movable portion, and the parallel light beams emitted from the pair of second objective lenses are A deflecting optical unit that leads to the binocular unit, and an optical path of each of the parallel light beams that are provided in the deflecting optical unit and are emitted from the pair of second objective lenses and incident on the pair of binocular units. Light shielding between the second objective lens and the pair of binoculars Characterized in that a light shielding member that.

  ADVANTAGE OF THE INVENTION According to this invention, even if it has a movable mechanism inside, the lens-barrel which can light-shield the right and left optical path can be provided.

It is a side view showing the whole composition of the parallel system stereomicroscope concerning an embodiment. It is a figure which shows typically the whole optical system of the parallel system stereomicroscope which concerns on embodiment. It is sectional drawing (arrow arrow view of the cross section along the BB line in FIG. 4) which shows the state which looked at the lens-barrel of the parallel system stereomicroscope based on embodiment from the left side seeing from the observer. FIG. 4 is a cross-sectional view taken along the line AA in FIG. 3. It is a figure which shows the relationship of the angle of a mirror holding member and a binocular part. It is sectional drawing which shows the state which inclined the binocular part by the predetermined angle from the state of FIG. It is sectional drawing which shows the state which looked at the lens-barrel of the parallel system stereomicroscope based on a 1st modification from the observer's left side. It is sectional drawing which shows the state which looked at the lens-barrel of the parallel system stereomicroscope based on a 1st modification from the observer side. It is a figure which shows the state which switched the optical path switching prism from the state of FIG. It is sectional drawing which shows the state which looked at the lens-barrel of the parallel system stereomicroscope concerning a 2nd modification from the left side seeing from the observer. It is a figure which expands and shows an objective lens and a part by the side of the object of a variable magnification optical system.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In this specification, the viewer side is the front (front surface), and the vertical and horizontal directions refer to the state viewed from the viewer side.

  FIG. 1 is a side view showing the overall configuration of the parallel system stereomicroscope according to the present embodiment, and FIG. 2 is a diagram schematically showing the entire optical system of the parallel system stereomicroscope according to the embodiment. .

  As shown in FIG. 1, a parallel system stereomicroscope 1 according to the present embodiment (hereinafter simply referred to as a microscope 1) includes a base portion 2, a support column 3 provided perpendicular to the base portion 2, and a support column 3. And a movable body 4 provided to be movable in the direction. The base unit 2 is provided with a stage 5 on which an object is placed. The moving body 4 moves up and down along the support column 3 by adjusting the knob 4a. A variable power unit 10 is attached to the moving body 4. The zoom unit 10 includes an objective lens 7 and a lens barrel 13. The lens barrel 13 includes a binocular unit 37 and an eyepiece lens 25. The lens barrel 13 of the microscope 1 according to the present embodiment is an inclination lens barrel capable of changing the inclination angle of the binocular unit 37 and the eyepiece lens 25 to an observer's desired angle.

  As shown in FIG. 2, the microscope 1 according to the present embodiment includes left and right observation optical systems 16L and 16R. The left observation optical system 16L includes, in order from the object side, the left and right common objective lens 7, the variable magnification optical system 19L provided in the variable magnification unit 10, the second objective lens 22L and the eyepiece 25L provided in the lens barrel 13. And. The variable magnification optical system 19L includes an aperture stop (not shown). The second objective lens 22L is for forming an object image on the left imaging surface 28L. The right observation optical system 16R has the same configuration as the left observation optical system 16L, and the objective lens 7 common to the left and right, the variable magnification optical system 19R provided in the variable magnification unit 10, and an aperture stop (not shown). ) And a second objective lens 22R and an eyepiece lens 25R provided in the lens barrel 13. The objective lens 7 plays a role of guiding parallel light beams to the subsequent variable magnification optical systems 19L and 19R for the left eye and right eye. The parallel luminous flux emitted from the objective lens 7 is divided into left and right independent optical paths and guided to the variable magnification optical systems 19L and 19R, respectively. Light beams emitted from the left and right variable magnification optical systems 19L and 19R are incident on the lens barrel 13 via the second objective lenses 22L and 22R, respectively.

  Illumination light for illuminating an object (not shown) is guided to the zoom unit 10 from an illumination optical system (not shown). The illumination light guided to the zoom unit 10 is irradiated onto the object via the objective lens 7. Since the microscope 1 according to the present embodiment is a parallel system, left and right optical paths are provided independently to stereoscopically view an object, and the optical axes IL and IR of the left and right optical paths intersect on the object plane. Yes.

  Next, the lens barrel 13 of the microscope 1 according to this embodiment will be described in more detail.

  FIG. 3 is a cross-sectional view (a cross-sectional view taken along line BB in FIG. 4) showing a state in which the lens barrel 13 of the microscope 1 according to the present embodiment is viewed from the left hand side when viewed from the observer. . 4 is a cross-sectional view taken along the line AA of FIG.

  As shown in FIGS. 3 and 4, the lens barrel 13 includes a lens barrel main body 31 (hereinafter referred to as a main body 31) fixed to the zoom unit 10, and a binocular holder 34 arranged inside the main body 31. And left and right binocular units 37L and 37R provided in the binocular unit holder 34, and eyepieces 25L and 25R provided in the binocular units 37L and 37R, respectively. The main body 31 and the binocular unit holder 34 are members common to the left and right optical paths, and the binocular units 37L and 37R and the eyepieces 25L and 25R are independent members for the left and right optical paths. A round ant 40 is formed at the bottom of the main body 31. On the other hand, a dovetail groove (not shown) that engages with the round dovetail 40 of the main body 31 is provided in the upper portion of the zoom unit 10. The lens barrel 13 is attached and fixed to the zoom unit 10 by the engagement between the round dovetail 40 of the main body 31 and the dovetail groove of the zoom unit 10.

  The left and right second objective lenses 22L and 22R are fixed to the inner diameter side of the round ant 40. Light beams transmitted through the left and right variable magnification optical systems 19L and 19R and emitted from the variable magnification optical systems 19L and 19R are transmitted through the left and right second objective lenses 22L and 22R, respectively, and are guided into the lens barrel 13. Light beams emitted from the left and right second objective lenses 22L and 22R are incident on optical path switching prisms 43a and 43b provided at the bottom of the main body 31, respectively. The optical path switching prism is provided for the purpose of dividing the optical path from the variable magnification optical systems 19L and 19R into the photographing optical system, and has a structure that can be switched to change the divided light quantity ratio. In the present embodiment, as shown in FIG. 4, three optical path switching prisms 43a, 43b, 43c are provided. The three optical path switching prisms 43a, 43b, 43c are provided on the support member 46 side by side in the left-right direction, that is, in a direction perpendicular to the pair of optical axes IL, IR of the second objective lenses 22L, 22R. They are 43a and 43b for the observation optical system and 43c for the photographing optical system in order from the left side. The shapes and sizes of the optical path switching prisms 43a, 43b, and 43c are similarly formed. Each of the optical path switching prisms 43 a, 43 b, 43 c has an upper half exposed from the upper surface of the support member 46, and the remaining lower side is located inside the support member 46. The support member 46 is slidably supported by a guide member 49 provided on the bottom of the main body 31 so as to extend in the left-right direction. When the observer operates a switching operation unit (not shown), the support member 46 slides on the guide member 49 and the prisms incorporated in the left and right optical paths are switched.

  As for the main-body part 31, the upper part and the upper part of the wall by the side of an observer are an open state. A binocular holder 34 is disposed in the opening of the main body 31. The left and right walls of the binocular holder 34 are rotatably supported by the left and right walls of the main body 31. In other words, the binocular holder 34 is pivotable in the vertical direction within a predetermined range with respect to the main body 31 around a pivot center C penetrating the main body 31 in the left-right direction. The lower side of the binocular holder 34 is in an open state so that the light beams emitted from the optical path switching prisms 43a and 43b (43c) are guided inside.

  The left and right binocular portions 37L and 37R and the eyepieces 25L and 25R respectively provided on the left and right binocular portions 37L and 37R protrude from the binocular portion holder 34 toward the viewer. The rhombus prisms 52L and 52R are provided inside the left and right binocular portions 37L and 37R, respectively. The binocular units 37L and 37R are provided in the binocular unit holder 34, and the eyepieces 25L and 25R are provided in the binocular units 37L and 37R, respectively. Therefore, when the binocular unit holder 34 rotates, the binocular unit holder 34 rotates. Accordingly, the left and right binocular portions 37L and 37R and the eyepieces 25L and 25R are rotated in the vertical direction.

  On the inner side of the binocular unit holder 34, the light beams incident on the lens barrel 13 from the variable magnification optical systems 19L and 19R via the second objective lenses 22L and 22R are deflected to form rhomboid prisms for the binocular units 37L and 37R, respectively. A deflecting optical unit 55 for guiding to 52L and 52R is arranged. The deflection optical unit 55 rotates in conjunction with the rotation of the binocular unit holder 34 as will be described later. In the following description, as shown in FIGS. 3 and 4, a state in which the incident optical axis angle to the binocular units 37L and 37R is horizontal (0 °) will be described. The incident optical axis angle to the binocular units 37L and 37R is the inclination angle of the binocular units 37L and 37R.

  The deflection optical unit 55 includes a mirror holding member 58 having a plurality of chevron shapes formed on one surface of the plate-like member, and a plurality (four in this embodiment) of reflection mirrors fixed to the mirror holding member 58. It is composed of The mirror holding member 58 is arranged on the inner side of the binocular holder 34 with the surface on which the chevron shape is formed facing the observer side and the upper part inclined to the observer side. The reflection mirror is for guiding the light beams emitted from the optical path switching prisms 43a and 43b to the binocular units 37L and 37R by changing the directions of the right and left optical paths, respectively. On one side of the mirror holding member 58, three ridge portions 64a, 64b, 64c extending in the vertical direction of the mirror holding member 58 are formed at the center and both ends in the left-right direction, and the center ridge portion 64b and The centers of the leftmost ridge portion 64a and the centers of the central ridge portion 64b and the rightmost ridge portion 64c are valley portions 67a and 67b, respectively. These ridges 64a, 64b, 64c and valleys 67a, 67b form three peaks 70a, 70b, 70c, and these three peaks 70a, 70b, 70c form four Slopes 73a, 73b, 73c, and 73d are formed. The three peak portions 70a, 70b, and 70c are symmetrical on the whole.

  One reflection mirror 61a, 61b, 61c, 61d is attached to each of the four inclined surfaces 73a, 73b, 73c, 73d of the mirror holding member 58, and two reflection mirrors 61a, 61b, 61c, 61d are provided on each of the left optical path and the right optical path. A slight gap is provided between the reflecting mirrors 61b and 61c attached to the slopes 73b and 73c sandwiching the central ridge 64b, with the ridge 64b interposed therebetween. Of the two reflecting mirrors 61a and 61b provided in the left optical path, the inner reflecting mirror 61b reflects the light beam emitted from the optical path switching prism 43a toward the outer reflecting mirror 61a. The outer reflection mirror 61a reflects the light beam reflected by the inner reflection mirror 61b toward the rhombus prism 52L on the viewer side. Similarly, the two reflecting mirrors 61c and 61d in the right optical path reflect the light beam emitted from the optical path switching prism 43b toward the outer reflecting mirror 61d. The outer reflection mirror 61d reflects the light beam reflected by the inner reflection mirror 61c toward the observer-side rhomboid prism 52R. The optical axes of the light beams incident on the left and right rhombus prisms 52L and 52R from the two outer reflection mirrors 61a and 61d are parallel, and the width between these optical axes is the width of the optical axis in the variable magnification optical systems 19L and 19R. Is wider than. The light beams incident on the left and right rhombus prisms 52L and 52R are reflected twice by the reflection surfaces of the rhombus prisms 52L and 52R, respectively, and the light beams emitted from the rhombus prisms 52L and 52R are imaged on the imaging surfaces 28L and 28R, respectively. . Thus, a light beam emitted from an object (not shown) is converted into a parallel light beam through the objective lens 7 and is divided into two and incident on a pair of independent variable magnification optical systems 19L and 19R. An image is formed on the imaging surfaces 28L and 28R via the lenses 22L and 22R, the optical path switching prisms 43a and 43b, the reflection mirrors 61a, 61b, 61c and 61d, and the rhomboid prisms 52L and 52R, and the observer forms the eyepieces 25L and 25R. The image can be observed through the

  The mirror holding member 58 is supported by the binocular unit holder 34 via a gear mechanism 76 provided on the main body unit 31 and the binocular unit holder 34, and in conjunction with the vertical rotation of the binocular unit holder 34, the binocular unit holder 34 can be rotated in the same direction. The rotation center of the mirror holding member 58 is concentric with the rotation center C of the binocular holder 34, and the rotation center C of the binocular holder 34 is located through the center of the mirror holding member 58 in the left-right direction. .

  FIG. 5 is a diagram illustrating a relationship of rotation angles between the mirror holding member 58, the binocular unit 37L (37R), and the eyepiece 25L (25R). The rotation angle of the mirror holding member 58 is set by the gear mechanism 76 to be exactly θ / 2 with respect to the rotation angle θ of the binocular holder 34. That is, the rotation of the binocular unit holder 34 is decelerated by half and transmitted to the mirror holding member 58.

  The gear mechanism 76 is connected to the gear 76 a fixed integrally with the main body 31 concentrically with the rotation center C of the binocular holder 34, the gear 76 b meshing with the gear 76 a, the other main body 31 and the binocular holder 34. A plurality of gears (not shown) are provided. When these gears mesh and rotate, the mirror holding member 58 is configured to rotate in the same direction by a half rotation angle with respect to the rotation angle of the binocular unit holder 34. Thus, by setting the rotation angle of the mirror holding member 58 to θ / 2 with respect to the rotation angle θ of the binocular unit holder 34, the binocular unit 37L is reflected by the reflection mirrors 61a, 61b, 61c, 61d. , 37R rhombus prisms 52L and 52R, the optical axes of the light beams incident on the rhombus prisms 52L and 52R are not shifted even when the binocular holder 34 is rotated.

  In this embodiment, the mirror holding member 58 of the deflection optical unit 55 is provided with a light shielding member 79 that optically blocks the left and right optical paths in the lens barrel 13. In other words, a light shielding member 79 that shields the left and right optical paths in the lens barrel 13 from each other is provided. The light shielding member 79 is a metal thin plate formed in a substantially semicircular shape, and includes an arc-shaped portion 79a and a straight portion 79b connecting both ends of the arc-shaped portion 79a. The arc of the arc-shaped portion 79a has a shape that is almost a semicircle. The surface of the light shielding member 79 is painted with matte black. In place of matte coating, light shielding paper or the like may be attached to the surface. The light shielding member 79 is provided at the center between the left and right optical axes so as to partition the binocular holder 34 in half in the left and right direction. The light blocking member 79 is attached to the mirror holding member 58 by providing a groove in the central portion of the mirror holding member 58, that is, the ridge portion 64b of the central peak portion 70b among the three peak portions 70a, 70b, 70c. The straight portion 79b is fitted into this groove and fixed by adhesion or the like. Therefore, the arc-shaped portion 79a of the light shielding member 79 is arranged upright from the central ridge portion 64b. The center of the circle including the arc-shaped portion 79 a of the light shielding member 79 is concentric with the rotation center C of the binocular unit holder 34. The edge of the arc-shaped portion 79a of the light shielding member 79 is positioned immediately above the straight line connecting the upper ends of the optical path switching prisms 43a and 43b between the optical path switching prisms 43a and 43b, and the observer side is the binocular portion. Between the 37L and 37R, it is located in the very vicinity of the binocular part 37L, 37R side wall of the binocular part holder 34. Further, both ends of the arc-shaped portion 79a are in the state shown in FIGS. 3 and 4, that is, in the state where the incident optical axis angle to the binocular portions 37L and 37R is horizontal (0 °), one side is the optical path switching prism 43a, It wraps around to the rear side rather than the position of 43b, and the other side wraps around to the upper side from the incident position of the light beam to the binocular portions 37L and 37R. That is, the length of the arc-shaped portion 79a is sufficiently longer than the arc connecting the position immediately above the optical path switching prisms 43a and 43b and the incident position of the light beam on the binocular portions 37L and 37R. In this state, the range in which the light shielding member 79 optically separates the left and right optical paths is such that the light beam guided into the lens barrel 13 is emitted from the optical path switching prisms 43a and 43b, and two reflections are made. Up to just before entering the rhomboid prisms 52L and 52R after being refracted by the mirrors 61a and 61b and 61c and 61d. By shielding the optical paths in this range from each other, the left and right optical paths passing through the lens barrel 13 are shielded over almost the entire area.

  6 is a cross-sectional view showing a state where the binocular units 37L and 37R and the eyepieces 25L and 25R are tilted upward by an angle θ from the state of FIG. Note that the angle θ is the maximum inclination angle of the optical axis angle incident on the binocular portions 37L and 37R.

  As shown in FIG. 6, when the binocular portions 37L and 37R and the eyepieces 25L and 25R are tilted upward by an angle θ, the mirror holding member 58 is moved upward by θ / 2 via the gear mechanism 79 as described above. It will tilt. At this time, since the light shielding member 79 is fixed to the mirror holding member 58, it rotates together with the mirror holding member 58 by θ / 2. Since the center of the circle including the arc-shaped portion 79a of the light shielding member 79 is the rotation center C of the binocular holder 34, that is, the rotation center of the mirror holding member 58, the arc-shaped portion 79a of the light shielding member 79 corresponds to the angle θ / 2. Move upward along the arc as much as you do. Therefore, the arrangement state of the light shielding member 79 in the binocular unit holder 34 at this time is naturally different from the state in FIG. 3 before the binocular units 37L and 37R are tilted. However, the edge of the arc-shaped portion 79a is positioned immediately above the straight line connecting the upper ends of the optical path switching prisms 43a and 43b between the optical path switching prisms 43a and 43b, and the observer side has binocular sections 37L and 37R. The binocular portion holder 34 is positioned very close to the binocular portion 37L, 37R side wall. Therefore, even in a state where the binocular portions 37L and 37R are inclined, the light beam guided into the lens barrel 13 is emitted from the optical path switching prisms 43a and 43b in the range where the light shielding member 79 separates the left and right optical paths. From this point, the light is refracted by the two reflecting mirrors 61a, 61b and 61c, 61d, and immediately before entering the rhomboid prisms 52L, 52R. That is, the range that separates the left and right optical paths is the same as the state before the binocular portions 37L and 37R are tilted. As described above, in the present embodiment, the light shielding member 79 covers the light shielding range so that the light shielding member 79 covers the light shielding range over an angle range from the lower limit (horizontal) to the upper limit (θ). The radius of curvature and the length of the arc-shaped portion 79a are configured. Thereby, even if the angles of the binocular portions 37L and 37R are changed, the light shielding effect in the lens barrel 13 does not change, and the same light shielding effect can always be maintained.

  As described above, according to the lens barrel 13 according to the present embodiment, the light in the left optical path enters the right optical path by the light shielding member 79 even if it has a movable mechanism inside. Intrusion into the left optical path can be prevented. Moreover, even if the angles of the binocular portions 37L and 37R are changed, the light shielding effect does not change, and the same light shielding effect can always be maintained. As a result, it is possible to prevent the contrast from being lowered due to flare caused by stray light.

  Further, since no light shielding member is provided between the left and right optical paths of the variable magnification optical systems 19L and 19R, the left and right lenses located closest to the object side of the variable magnification optical systems 19L and 19R are in contact with each other or very much. They can be juxtaposed at short intervals. For this reason, the effective diameter of the lens is not reduced.

(First modification)
Next, a first modification of the above embodiment will be described. In addition, about the same structure as the said embodiment, it demonstrates using the same code | symbol.

  FIG. 7 is a cross-sectional view showing a state in which the lens barrel 13 according to the first modification is viewed from the left side (a cross section corresponding to the line BB in FIG. 4), and FIG. 8 is from the viewer side. It is sectional drawing which shows the state (cross section corresponding to the AA line in FIG. 3). The first modification is different from the above embodiment in that a light blocking member is also provided in the optical path switching prisms 43a, 43b, and 43c. Other configurations are the same as in the above embodiment.

  The upper half of the three optical path switching prisms 43a, 43b, 43c is exposed from the upper surface of the support member 46, and the remaining lower side is located inside the support member 46, as in the above embodiment. In the first modification, the second light blocking member 82a, between the left optical path switching prism 43a and the central optical path switching prism 43b, and between the central optical path switching prism 43b and the right optical path switching prism 43c, respectively. 82b is provided. The second light shielding members 82a and 82b are formed of a thin metal plate and have a substantially rectangular shape, and the surface is painted matte black. In place of matte coating, light shielding paper or the like may be attached to the surface.

  The second light shielding member 82a provided between the left optical path switching prism 43a and the central optical path switching prism 43b is in contact with the right side surface of the left optical path switching prism 43a, and the lower side is the upper surface of the support member 46. It is fixed to. The second light shielding member 82a is formed such that the dimension in the front-rear direction is larger than the dimension in the front-rear direction of the optical path switching prism 43a. The vertical dimension is formed larger than the vertical dimension of the portion exposed from the support member 46 of the optical path switching prism 43a. As described above, the second light shielding member 82a is formed larger than the side surface of the portion exposed from the support member 46 of the optical path switching prism 43a, and covers the side surface of the optical path switching prism 43a.

  The upper end portion of the second light shielding member 82a is aligned with the edge of the arc-shaped portion 79a of the light shielding member 79 attached to the mirror holding member 58 in the left-right direction, that is, the pair of optical axes IL, IR of the second objective lenses 22L, 22R. These are provided so as to overlap with each other in a direction intersecting at right angles with a slight gap. In the above embodiment, as shown in FIGS. 3 and 6, when the cross section of the lens barrel 13 is viewed from the left side, it is between the edge of the arc-shaped portion 79a of the light shielding member 79 and the upper ends of the optical path switching prisms 43a and 43b. There is a minute interval d in the vertical direction. In the first modification, a second light shielding member 82 a is provided between the left and right optical path switching prisms 43 a and 43 b, and the upper end portion of the second light shielding member 82 a is a light shielding member 79 provided on the mirror holding member 58. The left and right optical paths can be separated even at a minute distance d between the light shielding member 79 and the optical path switching prisms 43a and 43b, and the light shielding effect can be further enhanced. This effect does not change even if the binocular portions 37L and 37R are tilted.

  The second light shielding member 82b between the central optical path switching prism 43b and the right optical path switching prism 43c is in contact with the left side surface of the right optical path switching prism 43c, and the lower side is fixed to the upper surface of the support member 46. ing. As shown in FIG. 8, even if the optical path switching prisms 43a and 43b are incorporated in the left and right optical paths, the center and right optical path switching prisms 43b and 43c are switched to be incorporated in the left and right optical paths. As shown, the light path between the light blocking member 79 of the mirror holding member 58 and the optical path switching prisms 43b and 43c can be separated, and the light blocking effect does not change. That is, even if the optical path switching prisms incorporated in the left and right optical paths are switched, the light shielding range does not change, and the same light shielding effect is always exhibited. This effect does not change even if the binocular portions 37L and 37R are tilted.

(Second modification)
Next, a second modification of the above embodiment will be described. In addition, about the same structure as the said embodiment, it demonstrates using the same code | symbol.

  FIG. 10 is a cross-sectional view showing a state in which the lens barrel 213 according to the second modification is viewed from the left side when viewed from the observer (a cross section corresponding to the line BB in FIG. 4). The second modification differs from the above embodiment in that no optical path switching prism is provided in the barrel main body 231. Since the optical path switching prism is not provided, the height of the barrel main body 231 is smaller than that of the above embodiment. Other configurations are the same as in the above embodiment.

  In the lens barrel 213 according to the second modification, the edge of the arc-shaped portion 79a of the light shielding member 79 is positioned immediately above the wall on the bottom side of the main body 231 between the second objective lenses 22L and 22R on the lower side. The observer side is located between the binocular portions 37L and 37R, very close to the binocular portion 37L and 37R side wall of the binocular portion holder 34. Accordingly, the range shielded by the light shielding member 79 is such that the light beams incident on the second objective lenses 22L and 22R from the variable magnification optical systems 19L and 19R are emitted from the second objective lenses 22L and 22R, respectively. Up to just before entering the rhomboid prisms 52L and 52R after being refracted by the reflection mirrors 61a and 61b and 61c and 61d. The range shielded by the light shielding member 79 does not change even if the binocular portions 37L and 37R are tilted, as in the above embodiment. Also in the second modification, the left and right optical paths are shielded from each other over almost the entire area of the lens barrel 213. Therefore, also in the second modification, the same effect as that of the above embodiment can be exhibited.

  In the first modification, the second light shielding members 82a and 82b are provided between the optical path switching prisms 43a, 43b, and 43c. However, in the second modification in which the optical path switching prism is not provided, the left and right second By providing a second light shielding member similar to the first modification between the two objective lenses 22L and 22R, the light shielding effect can be further enhanced.

  As described above, even in the lens barrel 13 according to the first modification and the lens barrel 213 according to the second modification, the light shielding member 79, 82a (82b) can be used to It is possible to prevent light from entering the right optical path, and conversely, light from the right optical path from entering the left optical path. Moreover, even if the angles of the binocular portions 37 and 37 are changed, the light shielding effect does not change, and the same light shielding effect can always be maintained. As a result, it is possible to prevent the contrast from being lowered due to flare caused by stray light.

  In addition, since no light shielding member is provided between the left and right optical paths of the variable magnification optical systems 19L and 19R, the lenses on the left and right optical paths located closest to the object side of the variable magnification optical systems 19L and 19R are in contact with each other, or Can be juxtaposed at short intervals. For this reason, the effective diameter of the lens is not reduced.

  As mentioned above, although embodiment of this invention and its modification were demonstrated, the structure of this invention is not limited to this embodiment and modification. For example, in the present embodiment, a reflection mirror is used for the deflection optical unit 55, but a prism may be used instead of the reflection mirror. Thus, the present invention can be modified as appropriate.

DESCRIPTION OF SYMBOLS 1 Parallel system stereomicroscope 7 Objective lens 10 Variable magnification part 13, 213 Lens barrel 16 Observation optical system 19 Variable magnification optical system 22 Second objective lens 25 Eyepiece 28 Imaging surface 31,231 Lens barrel main part 34 Binocular part holder 37 Binocular part 43 Optical path switching prism 52 Rhombus prism 55 Deflection optical part 58 Mirror holding member 61 Reflection mirror 64 Ridge part 67 Valley part 70 Mountain part 73 Slope 76 Gear mechanism 79 Light shielding member 79a Arc part 79b Linear part 82 Second light shielding member

Claims (8)

The lens barrel body,
A pair of independent second light beams that are provided in the lens barrel main body and are emitted from an object and transmitted through an objective lens and a pair of independent variable magnification optical systems to form an image of the object. An objective lens;
A movable part rotatably supported by the lens barrel body part;
A pair of independent binocular units that are provided in the movable part and each of which has an inclination angle variable by rotating together with the movable part;
A deflecting optical unit that rotates in conjunction with the rotation of the movable unit and guides the parallel light beams emitted from the pair of second objective lenses to the pair of binocular units,
Provided in the deflecting optical unit, the respective optical paths of the parallel light beams emitted from the pair of second objective lenses and incident on the pair of binocular units are changed to the pair of second objective lenses and the pair of pairs. A lens barrel comprising a light shielding member that shields light from the binocular part.   The light shielding member has an arc shape concentric with the rotation center of the movable portion, rotates with the deflection optical unit about the rotation center of the movable portion, and is emitted from the pair of second objective lenses. The optical paths of the parallel light beams incident on the pair of binocular parts are between the pair of second objective lenses and the pair of binocular parts regardless of the rotation angle of the movable part, The lens barrel according to claim 1, wherein light is shielded from each other without changing a light shielding range between the parallel light beams.   The deflection optical unit includes an optical member that reflects the parallel light beam emitted from the pair of second objective lenses, and the optical member and the light shielding member are provided close to the deflection optical unit. The lens barrel according to claim 1 or 2, wherein   The lens barrel main body is provided with a plurality of optical path switching members that can be selectively incorporated in the optical paths of the parallel light beams emitted from the pair of second objective lenses. Item 4. The lens barrel according to any one of Items 1 to 3.   The lens barrel according to claim 4, wherein the plurality of optical path switching members are linearly arranged, and a second light shielding member is provided between the adjacent optical path switching members.   The light-shielding member and the second light-shielding member are disposed so as to have a portion overlapping in a direction perpendicular to any of a pair of optical axes of the second objective lens. Item 6. The lens barrel according to Item 5.   The lens barrel according to claim 1, wherein the deflecting optical unit has a chevron shape on one surface, and the light shielding member is provided in the chevron shape.   A microscope comprising the lens barrel according to any one of claims 1 to 7.

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