JP2001075011A - Stereoscopic microscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form right and left images having uniform brightness on an image pickup surface by correcting the respective deviation of the illuminance of right and left subject images caused by that the object light of the pair of photographing optical systems of a stereoscopic microscope is reflected by each reflection member. SOLUTION: The stereoscopic microscope possesses the pair of the photographing optical systems separated by a prescribed base line length and forming the pair of images for the same observation object and a convergence prism 260 to guide the optical axis of each photographing optical system to right and left image pickup areas on the image pickup surface of a CCD 116 by respectively shifting in parallel in directions in which they approach with each other. Density distribution filters 1 and 2 having the gradient of transmissivity by which it is increased from one end to the other end in a base line length direction are respectively arranged right before the incident end surfaces 261c and 262c of the prism 260, and a part of the luminous flux of each object light transmitted through each photographing optical system is shielded, so that specified luminous flux density is given to the object light.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of enlarging and temporarily forming an image of an object to be observed by a pair of photographing optical systems, and re-forming the image of the object to be imaged on an imaging surface. To a stereo microscope.

[0002]

2. Description of the Related Art Conventionally, a microscope for enlarging and forming an image of an object to be observed has been used for treating a fine tissue as in neurosurgery. That is, since organs composed of fine tissues such as the brain are difficult to visually discriminate the structural tissues, such organs must be treated under a microscope. Moreover, with a monocular microscope, it is impossible to recognize the three-dimensional structure of the tissue, so in order to enable accurate treatment by observing the tissue three-dimensionally,
Stereoscopic microscopes are used for such procedures.

[0003] As such a stereo microscope, there is a video stereo microscope. This video stereo microscope (hereinafter referred to as
An optical configuration in which an image of the same observation target is respectively formed by a pair of photographing optical systems separated by a predetermined base line length is employed in a “stereoscopic microscope”. And
A camera such as a CCD that captures left and right images created by the respective imaging optical systems is arranged in the stereoscopic microscope in order to monitor the image of the observation target to the main surgeon or other persons involved in the operation. A stereoscopic viewer is used as a monitor for displaying the image of the camera so that the observer can capture the image of the observation target as a stereoscopic image. This stereoscopic viewer displays left and right images of the observation object taken by the camera on a display such as an LCD panel, and displays the displayed left and right images with a pair of loupes prepared for the left and right eyes. It is a device for observation. Therefore, in order for the imaging surface of the camera and the display surface of the display to be effectively used, the left and right video regions must be configured to contact each other at a predetermined boundary.

In view of this, portions conjugate to the outside of the boundary line in the image (primary image) of the observation object (subject) once formed by the objective optical system in each photographing optical system are each partitioned by a field frame, and Conventionally, a configuration has been proposed in which a pair of images separated by a frame is relayed by a relay optical system of each photographing optical system and re-imaged as a secondary image on each of left and right imaging areas of an imaging surface of a camera. I have. According to this configuration, each imaging region on the imaging surface is clearly divided, and the subject light transmitted through one imaging optical system is incident on the imaging region corresponding to the other imaging optical system on the imaging surface.
Is prevented.

[0005] The distance between the centers of the left and right imaging areas on the imaging plane divided as described above is sufficiently smaller than the base line length of the left and right imaging optical systems. Therefore, the subject light transmitted through each relay optical system must be shifted in parallel in a direction approaching each other, and form secondary images in the left and right imaging regions, respectively. Therefore, between the relay optical system of both photographing optical systems and the imaging surface, a pair of reflecting members that reflect subject light transmitted through each relay optical system in a crank shape and enter each imaging region on the imaging surface. Is arranged.

Each of the reflecting members has two parallel reflecting surfaces, and the subject light incident from the incident side is reflected twice by the reflecting surfaces and emitted. At this time, since the traveling direction of the incident subject light and the traveling direction of the emitted subject light are parallel to each other, each reflecting member can translate the image formed by the relay optical system as it is. is there.

FIG. 26 shows a converging prism 400 comprising a pair of optical axis shift prisms 401 and 402 as an example of the pair of reflecting members. The convergence shifting prism 400 is formed in a pentagonal prism shape so as to be mutually plane-symmetric with respect to a boundary surface Bo1 which is perpendicular to the imaging surface along the boundary between the left and right imaging regions on the imaging surface of the CCD 116. A pair of optical axis shift prisms 401 and 402 thus formed are joined via the boundary surface Bo1, and have a substantially V-shaped planar shape as a whole.

Each optical axis shift prism 401, 402
First reflection surfaces 401a, 402a and second reflection surfaces 401b, 40 parallel to each other and inclined by 45 ° with respect to the boundary surface Bo1.
2b and an incident end surface 401 perpendicular to the boundary surface Bo1
c, 402c and the emission end faces 401d, 402d, and the second
Reflection surfaces 401b, 402b and emission end surfaces 401d, 40
It has bonding surfaces 401e and 402e adjacent to 2d and along the boundary surface Bo1.

Each of these optical axis shift prisms 401, 40
2, the optical axes Ax2 and Ax3 of the relay optical system passing through
First reflection surface 401a, 402a and second reflection surface 401
b, 402b, it is bent in a crank shape, advances parallel to and close to the boundary surface Bo1, and passes through the center of each imaging area on the imaging surface of the CCD. Therefore, each of these optical axis shift prisms 401, 402 is provided with an incident end face 401c, 40.
The object light incident from the second reflection surface 2c
The light is reflected toward the boundary surface Bo1 by a and 402a, further reflected by the inner second reflection surfaces 401b and 402b in the same direction as the boundary surface Bo1, and emitted from the emission end surfaces 401d and 402d perpendicular to the boundary surface Bo1. The exit end faces 401d of the optical axis shift prisms 401, 402,
Each of left and right object lights emitted from 402d is CCD1
The left and right images of the observation target (subject) are re-imaged in each imaging region of the 16 imaging surfaces.

[0010]

However, as described above, the subject light transmitted through the relay optical system of each photographing optical system is reflected in a crank shape by a pair of reflecting members, and is incident on each imaging area. In this case, as shown in FIG. 27, near the boundary line 120c between the left and right images 120a and 120b obtained by the imaging by the CCD 116,
A dark part with reduced illuminance occurs.

This is because the optical axis shift prism 401
Due to the structure in which the reflecting surface 401b and the second reflecting surface 402b of the optical axis shifting prism 402 are cut off at the joining surfaces 401e and 402e (accordingly, the boundary surface Bo1),
Second reflecting surface 4 that would be present without this notch
The light beams to be reflected at the portions of the first reflection surface 01b and the second reflection surface 402b extending to the opposite side of the boundary surface Bo1 (in FIG. 28, the second reflection surface 401b is indicated by a broken line 401b '),
This is because the light is lost without being reflected toward the CCD 116.

Therefore, in a portion near the boundary between the left and right imaging regions (intersecting line with the boundary surface Bo1) on the imaging surface of the CCD 116, some of the family rays that pass through the relay optical system and converge on the portion are missing. Therefore, a boundary line (a boundary surface Bo1) through which the light rays transmitted through the relay optical system are converged.
The illuminance of the image is lower and darker than at a site farther from. In other words, the left and right images (secondary images) formed on the imaging surface have a certain brightness at a portion distant from the boundary (boundary surface Bo1) with the other imaging region and have the boundary line (boundary surface Bo1). ), The illuminance distribution having a gradient (bias) that gradually darkens as the distance approaches
01 and 402 are formed respectively.

Therefore, the left and right images 120 obtained by capturing the left and right images having a bias in the illuminance distribution by the CCD 116 are obtained.
a and 120b have a bias in the illuminance distribution, so that when the observer looks into the stereoscopic viewer on which the left and right images 120a and 120b are projected, natural and clear stereoscopic vision or accurate A stereoscopic observation cannot be performed, and particularly in a brain surgery in which a main operator looks into a stereoscopic viewer, there is a problem that an extremely serious injury may be caused to an organ such as the brain.

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to correct the bias of the illuminance distribution of the left and right images of the observation object caused by the left and right subject light being reflected by each reflecting member. It is another object of the present invention to provide a stereoscopic microscope in which left and right object images having uniform brightness are formed on an imaging surface of an imaging device so that natural and accurate stereoscopic viewing can be performed.

[0015]

In order to achieve the above-mentioned object, the present invention provides a camera system comprising: a pair of photographing optical systems arranged at a predetermined base line distance from each other; In a stereoscopic microscope that forms an image of the same subject in each of two regions divided by a boundary line and simultaneously captures images with the imaging device, each of the photographing optical systems includes an objective that forms a primary image of the subject. Optics,
A relay optical system for relaying the primary image to re-image as a secondary image, and a first reflection surface and a second reflection surface formed in parallel with each other, and the optical axis of the relay optical system is set to the other relay A reflecting member that forms the secondary image in the imaging region by shifting the optical system to approach the optical axis of the optical system and guiding the image to a corresponding imaging region on the imaging surface; Correction means arranged on an optical path leading to a surface, substantially passing a light flux converging on a portion of the imaging surface near the boundary line, and partially reducing a light flux converging on a portion of the imaging surface away from the boundary line. Is provided.

According to the above configuration, a part of the luminous flux converging on a portion of the image pickup surface distant from the boundary line is reduced by the correction means, and the entire light is reflected by the reflection member, and is incident on the image pickup surface. I do. The light flux converging on a portion near the boundary line on the imaging surface is almost entirely passed by the correction unit, but only a part of the light is reflected by the reflection member and enters the imaging surface.

Accordingly, the stereoscopic microscope according to the present invention is configured such that subject light transmitted through each photographing optical system is reflected in a crank shape by each reflecting member and is incident on the image pickup surface, but is transmitted through each photographing optical system. Before the subject light forms an image, a correction to reduce a part of the luminous flux of the subject light is performed in advance by the correction unit, so that the luminous flux density bias which occurs uniformly when the subject light is reflected by the reflecting member is uniformly determined. And a secondary image having uniform illuminance can be formed on the imaging surface.

In order to form the secondary image with as few dark portions as possible near the boundary of the secondary image formed on the imaging surface, the secondary image is set perpendicular to the imaging surface along the boundary. It is desirable to arrange the edge on the imaging surface side of the second reflection surface of the reflection member of each imaging optical system as close as possible to the boundary surface. Therefore, the edges on the imaging surface side of the second reflection surface constituting each of the reflection members may be disposed with a slight gap between the second reflection surface and the boundary surface, or may be disposed in contact with the boundary surface. May be. Of course, even in such an arrangement, a dark portion is formed in the image near the boundary line, so it is necessary to correct the subject light with the correcting member constituting the present invention so that the dark portion is not formed in the secondary image. is there. Here, each reflecting member may be composed of two mirrors, or may be composed of a prism having a shape of a substantially parallelogram column.

In the present invention, the correction means for partially reducing the luminous flux of the subject light transmitted through each photographing optical system may be a flat plate-shaped density distribution filter having a predetermined transmittance gradient. Alternatively, a shielding member that blocks a part of the light beam by being arranged in a state of entering the light path from the side of the light path of the subject light may be used.

In the former density distribution filter, a transmittance gradient such that the transmittance increases from one end to the other end in the base line length direction may be formed on the transmission surface. A transmittance gradient may be formed on the transmission surface such that the transmittance has a predetermined uniform transmittance from one end to the vicinity of the center in the long direction, and the transmittance gradually increases from the vicinity of the center to the other end. . This density distribution filter equalizes the illuminance of the secondary image when the light flux converging on a portion of the imaging surface distant from the boundary line is directed to the transmission surface so as to pass through the lower transmittance. Can be.

If this density distribution filter is arranged on the optical path from the objective optical system to the image pickup surface, a part of the luminous flux of the subject light passing through the density distribution filter can be reduced. If a density distribution filter is arranged near the image forming surface of the primary image formed by the optical system or near the image forming surface of the secondary image formed by the relay optical system, the illuminance of the secondary image will be more accurate. It is possible to adjust well. Further, when this density distribution filter is arranged on the image forming surface of the primary image, it becomes possible to more precisely adjust the illuminance of the secondary image formed on the imaging surface.

The latter shielding member may be an aperture stop arranged so that the center of the aperture is decentered from the optical axis of each photographing optical system, or may be a shielding plate having a flat plate shape with a straight edge formed on one side. .

When the shielding member is an aperture stop, if the aperture stop is arranged so that a light beam converging on a portion near the boundary line on the image pickup plane passes through the center of the aperture, the aperture stop is separated from the boundary line. The inner edge of the aperture stop is arranged at a portion through which a light beam converging on the portion passes, and a part of the light beam can be blocked.

On the other hand, when this shielding member is a shielding plate,
By arranging this shielding plate in a state where the edge enters from the side in the traveling direction of the light beam, it is possible to partially block only the light beam that converges on a portion of the imaging surface distant from the boundary line.

Once the aperture stop or shield plate, which is a shielding member, is incorporated into a stereoscopic microscope, it is not necessary to adjust its aperture diameter, eccentric direction and eccentric distance, or position at all. Alternatively, the shielding plate may be slidable so that the aperture of both shielding members can be adjusted.

The above-mentioned shielding member is provided between the final surface of the relay optical system and the image forming surface of the secondary image, between the final surface of the objective optical system and the image forming surface of the primary image, or the image forming of the primary image. When disposed between the surface and the object side surface of the relay optical system, the illuminance of the secondary image can be adjusted more accurately.

However, if the shielding member is disposed too close to the image forming surface on which the primary image or the secondary image is formed, all the light beams converging on a portion of the imaging surface that is far from the boundary line will be blocked. Therefore, it is conceivable that an image is not formed in that portion. Also, the final surface of the objective optical system,
Or, if the shielding member is arranged at a position too close to the object side surface or the final surface of the relay optical system, the secondary image formed on the image pickup surface is only darkened as a whole and is separated from the boundary line on the image pickup surface. The function of partially blocking only the luminous flux of the subject light incident on the portion does not work.

[0028]

Embodiments of the present invention will be described below with reference to the drawings.

[0029]

Embodiment 1 A video stereo microscope according to a first embodiment described below (hereinafter simply referred to as “stereo microscope”).
Is used, for example, by being incorporated into an operation support system used in neurosurgery. This surgical support system combines a stereoscopic image (stereo image) obtained by video-taking a patient's tissue with a stereoscopic microscope with a CG (computer graphics) image created based on data of an affected part obtained in advance. Then, it is displayed on a stereoscopic viewer dedicated to the main engineer or a monitor for other staff, etc.
This is a system for recording on a recording device.

<Overall Configuration of Surgery Support System> FIG.
It is a system configuration diagram showing an outline of this surgery support system. As shown in FIG. 1, the surgery support system
A stereo microscope 101 and a high-vision CCD camera 10 attached near the upper end of the back of the stereo microscope 101
2, a microscope position measuring device 103 also mounted near the lower end, a counterweight 104 mounted on the upper surface of the stereoscopic microscope 101, a light guide 105 drawn from the side of the stereoscopic microscope 101 to the inside, and this light A light source device 106 for introducing illumination light to the stereoscopic microscope 101 through the guide 105, a surgical planning computer 108 having a disk device 107, a real-time CG creating device 109 connected to the microscope position measuring device 103 and the surgical planning computer 108, , An image synthesizing device 110 connected to the real-time CG creating device 109 and the high-vision CCD camera 102, a distributor 111 connected to the image synthesizing device 110, a recording device 115 connected to the distributor 111, and a monitor 114. And stereoscopic viewer 1 Etc. and a 3 are constituted.

The above-mentioned disk device 107 has a patient P
Images (CT scan images, MRI images, SPEC) obtained by previously imaging the affected area with various imaging devices
T images, angiographic images, etc.)
Three-dimensional data of the affected area and surrounding tissues created in advance based on these various images are stored. Note that this 3
The dimensional data is based on three-dimensional local coordinates defined with reference points (marking or the like) set at a specific part of the patient's outer skin or internal tissue as the origin, the shape of the affected part and the surrounding tissue,
The data specifies the size and position in a vector format or a map format.

The above-mentioned stereo microscope 101 is detachably fixed to the tip of the free arm 100a of the first stand 100 via a mount 100b attached to the back surface. Therefore, this stereo microscope 101
It is free to move within a radius that the free arm 100a of the first stand 100 can reach, and can be oriented in any direction. However, here, for convenience, the direction of the observation target object with respect to the stereo microscope 101 is defined as “down”, and the opposite direction is defined as “up”.

The optical configuration inside the stereo microscope 101 will be described in detail later.
As shown in FIG. 2, the observation target includes a large-diameter close-up optical system 210 having a single optical axis and a pair of right and left that converge light transmitted through different portions of the close-up optical system 210. Zoom optical system 220, 2
The left and right field stops 2 are formed by an objective optical system comprising
Primary images are formed at the positions 70 and 271 respectively.
These left and right primary images are formed by a pair of left and right relay optical systems 24.
0, 250, is introduced into the high-definition CCD camera 102, and has left and right imaging areas (vertical and horizontal aspect ratios: 9:16) on the CCD 116 having an imaging surface of a high-definition size (vertical and horizontal aspect ratio = 9: 16). 8), each is re-imaged as a secondary image.
In this optical system, the close-up optical system 210, one zoom optical system 220, and one relay optical system 240 constitute one photographing optical system.
The other zoom-up optical system 230 and the relay optical system 25
Reference numeral 0 denotes the other photographing optical system, and also forms a pair of photographing optical systems arranged at a predetermined base line distance.

The images formed in the left and right imaging regions on the imaging surface of the CCD 116 by the pair of photographing optical systems including the objective optical system 280 and the relay optical systems 240 and 250 are separated by a predetermined base line length. This is equivalent to a stereo image obtained by arranging left and right images respectively taken from the above two places. The output signal of the CCD 116 is generated as a Hi-Vision signal by the image processor 117 and output from the Hi-Vision CCD camera 102 to the image synthesizing device 110 as shown in FIG.

The stereoscopic microscope 101 has a built-in illumination optical system 300 (see FIG. 6) for illuminating the observation object existing near the focal point of the close-up optical system 210. Then, illumination light is introduced into the illumination optical system 300 from the light source device 106 via the light guide 105.

As shown in FIG. 1, the microscope position measuring device 103 attached to the stereo microscope 101 has a distance to an observation object (subject) existing on the optical axis of the close-up optical system 210 and a close-up optical system. The three-dimensional orientation of the optical axis of the system 210 and the position of the reference point are measured, and the position of the observation target in the local coordinates is calculated based on the measured information. Then, the microscope position measuring device 103 transmits the information of the direction of the optical axis and the position of the observation target (subject) to the real-time CG generating device 10.
Notify 9.

This real-time CG creation device 109
Based on the information of the direction of the optical axis and the position of the observation target (subject) notified from the microscope position measuring device 103 and the three-dimensional data downloaded from the surgical planning computer 108, the affected part (for example, , A tumor) is generated in real time as a CG image (for example, a wire frame image) equivalent to a stereoscopic view of the tumor. This CG image is
It is generated as a stereoscopic image (stereo image) with the same base line length and the same subject distance as the optical system in the stereoscopic microscope 101. Then, the real-time CG creation device 109 inputs a CG image signal indicating the CG image generated in this way to the image synthesis device 110 as needed.

The image synthesizing apparatus 110 converts the Hi-Vision signal of the actual observation object input from the Hi-Vision CCD camera 102 into a real-time CG generating apparatus 109.
Is superimposed by adjusting the scale of the CG image signal obtained from. In the image indicated by the high-definition signal in which the CG image signal is superimposed, the shape of the affected part,
The size and position are shown as a CG image such as a wire frame. The superimposed Hi-Vision signal is distributed by the distributor 111 to a stereoscopic viewer 113 for the main operator D, a monitor 114 for other surgical staff or an advisor at a remote location, and the recording device 11.
5, respectively.

The stereoscopic viewer 113 is provided on the second stand 1
Twelve free arms 112a are attached by hanging from the tips. Therefore, it is possible to arrange the stereoscopic viewer 113 according to a posture in which the main operator D can easily perform the treatment. FIG. 3 shows a schematic configuration of the stereoscopic viewer 113. As shown in FIG. 3, the stereoscopic viewer 113 includes a high-definition LCD panel 12.
0 is built in as a monitor. This LCD panel 1
When an image based on a high-definition signal from the distributor is displayed on the LCD 20, as shown in the plan view of FIG.
The left half of the D panel 120 displays a left-eye image 120b captured in the left imaging region of the CCD 116, and the right half thereof displays a right-eye image captured in the right imaging region of the CCD 116. 120a is displayed. The boundary line 120c between the left and right eye images 120a and 120b shifts or tilts depending on the position adjustment of the field stops 270 and 271 described later. The optical path in the stereoscopic viewer 113 is aligned with the LC along the boundary 120c formed when the field stops 270 and 271 are accurately adjusted.
It is divided into left and right by a partition 121 installed vertically on the surface of the D panel 120. On both sides of the partition 121, a wedge prism 119 and an eyepiece 118 are arranged in this order from the LCD panel 120 side. The eyepiece 118 is a lens that enlarges and forms a virtual image of an image displayed on the LCD panel 120 at a position about 1 m (-1 diopter) in front of the observation eye I. The wedge prism 119 corrects the traveling direction of light so that the angle of convergence of the observation eye I is equal to the angle at which an object existing 1 m ahead is observed, thereby enabling natural stereoscopic observation.

As described above, an image stereoscopically viewed by the stereoscopic viewer 113 or an image displayed on the monitor 114 includes, as described above, a tumor which has been detected based on images previously photographed by various photographing devices. CG such as a wire frame showing the shape, size and position of the affected part such as
But has been superimposed. Therefore, the main operator D or other surgical staff observing them can easily identify an affected part that is difficult to identify in an actual image. As a result, accurate and prompt treatment can be performed.

<Configuration of Stereo Microscope> Next, the specific configuration of the above-described stereo microscope 101 (including the high-vision CCD camera 102) will be described in detail.

As shown in the perspective view of FIG. 5, the stereo microscope 101 has a flat rear surface to which the high-definition CCD camera 102 is attached and chamfered both side edges of the front surface (opposite side of the rear surface). It has a substantially prismatic shape.
In the center of the upper surface, the above-described light guide 105
An insertion opening (not shown) into which a guide pipe 122, which is a cylindrical member whose tip is inserted and fixed, is inserted. The annular member (fiber guide insertion portion) 123 attached to the opening of the insertion port is a chuck for fixing the guide pipe 122 inserted in the insertion port.

This stereoscopic microscope 101 has a light guide 1
The illumination optical system 300 for illuminating the observation target with the illumination light guided from the light source device 106 by the light source 05 and the imaging optical system for electronically photographing the left and right images of the same observation target (subject) (a pair of imaging optics) (System) 200 is built in.
Hereinafter, the optical configurations of the illumination optical system 300 and the photographing optical system (a pair of photographing optical systems) 200 will be sequentially described.

In the description of the optical system, "left and right"
Is a direction that coincides with the longitudinal direction of the imaging surface when projected on the CCD 116, and “up and down” is a direction that is orthogonal to the horizontal direction on the CCD 116.

[Optical Configuration of Illumination Optical System] First, the optical configuration of the illumination optical system 300 including the light guide 105 is shown in FIG.
This will be described with reference to FIG. As shown in FIGS. 6 and 7, the illumination optical system 300 of the stereo microscope 101 includes illumination light (divergent light) emitted from the light guide 105.
And a wedge prism 320 for matching the illumination range and the photographing range.

The optical axis Ax4 of the illumination lens group 310 is shown in FIG.
As shown in FIG.
The optical axis Ax1 is arranged in a direction parallel to the optical axis Ax1, but is decentered by a predetermined amount with respect to the optical axis Ax1. For this reason, the center of the illumination range in which the illumination lens group 310 irradiates the illumination light does not coincide with the center of the imaging range in which the close-up optical system 210 captures the observation target light, so that the illumination light amount is wasted. . Therefore, the illumination optical system 300
Is provided below the illumination lens group 310 with a wedge prism 320 oriented in a predetermined direction so that the illumination light emitted from the illumination lens group 310 can be effectively applied to the imaging range.

[Optical Configuration of Photographing Optical System] Next, the optical configuration of the stereoscopic microscope 101 will be described with reference to FIGS. 6 is a perspective view showing the entire configuration of the microscope optical system, FIG. 7 is a side view, FIG. 8 is a front view, and FIG. 9 is a plan view. Hereinafter, the configuration of each optical system will be described in order.

Imaging optical system (a pair of imaging optical systems) 200
As described above, the objective optical system 280 including one close-up optical system 210 and a pair of left and right zoom optical systems 220 and 230 as a whole is
A pair of left and right relay optical systems 240 and 250 for relaying a primary image of an observation object (subject) formed by the objective optical system 280 to form a secondary image of the subject; And a convergence approaching prism 260 for bringing the respective subject lights from the lens 250 closer to each other.

Field stops 270 and 271 are arranged at positions where the primary images are formed by the zoom optical systems 220 and 230, respectively, and a pentaprism 272 that deflects the optical path at right angles to the relay optical systems 240 and 250. , 273 and each of the relay optical systems 240, 25
Density distribution filters 1 and 2 for biasing the illuminance distribution of each subject light that passes through the relay optical system are disposed between 0 and the convergence shifting prism 260, respectively.

The optical axes Ax2 and Ax3 of the pair of left and right zoom optical systems 220 and 230 constituting the objective optical system 280 and the optical axis Ax4 of the illumination optical system 300 are aligned within the casing of the stereoscopic microscope 101 in the longitudinal direction of the casing. And are provided in parallel. Each of these zoom optical systems 22
The optical axes of the relay optical systems 240 and 250, which are coaxial with 0 and 230 via the pentaprisms 272 and 273, are directed in a direction perpendicular to the longitudinal direction of the casing of the stereoscopic microscope 101.

As shown in FIG. 6 to FIG. 8, the close-up optical system 210
It is configured by arranging a lens 211 and a positive second lens 212. The second lens 212 is movable in the optical axis direction, and by adjusting the movement thereof, it is possible to focus on an observation target (subject) at different distances. That is, the close-up optical system 210 is adjusted so that the observation target (subject) is located at the focal position, and has a collimating function of converting divergent light from the subject into substantially parallel light.

The first lens 211 and the second lens 212 of the close-up optical system 210 have a shape (D-cut shape) in which a part of the edge is cut out along a plane parallel to the optical axis Ax1. The close-up optical system 2 is located adjacent to a planar notch surface generated by the notch.
The illumination optical system 300 is arranged with its optical axis directed parallel to the ten optical axes.

The pair of zoom optical systems 220 and 230 image the subject light from the close-up optical system 210 at infinity at the positions of the field stops 270 and 271, respectively.

As shown in FIGS. 6 to 8, one zoom optical system 220 includes first to fourth lens groups 221 having positive, negative, negative, and positive powers, respectively, from the close-up optical system 210 side. , 222, 223, 224,
Be composed. Further, the zoom optical system 220 performs zooming by moving the second lens 222 and the third lens 223 in the optical axis direction while the first lens group 221 and the fourth lens group 224 are fixed. At this time, the magnification is changed by moving the second lens 222, and the focal position is kept constant by moving the third lens 223.

The other zoom optical system 230 has the same configuration as the above-described zoom optical system 220, and includes first to fourth lens groups 231, 232, 233, and 234. These zoom optical systems 220 and 230 are linked by a drive mechanism (not shown), and can simultaneously change the photographing magnification of the left and right images.

Optical axis Ax of zoom optical systems 220 and 230
2, Ax3 is the optical axis Ax of the close-up optical system 210
1 and parallel to the zoom optical system 220, 2
The plane including both the optical axes Ax2 and Ax3 is parallel to the plane and includes the optical axis of the close-up optical system 210, and as shown in FIG.
Just away.

The diameter of the close-up optical system 210 is set to be larger than the diameter of a circle containing the maximum effective diameter of the zoom optical systems 220 and 230 and the maximum effective diameter of the illumination optical system 300. As described above, the zoom optical system 220,
Close-up optical system 2 of 230 optical axes Ax2 and Ax3
By setting the optical axis Ax1 at a position further away from the cutout surface than the ten optical axes Ax1, the illumination optical system 300 can also be accommodated within the diameter occupied by the close-up optical system, and the whole can be compacted.

The field stops 270 and 271 are arranged at the positions of the primary images formed by the zoom optical systems 220 and 230. As shown in FIG. 6, the field stops 270 and 271 have a circular outer edge, and have substantially semicircular openings on the inner side in the left-right direction. Each field stop 270, 27
Reference numeral 1 denotes an arrangement in which the linear edge of the opening is aligned with the direction corresponding to the boundary between the left and right imaging areas on the imaging surface of the CCD 116, and is arranged so as to transmit only the light flux inside the same. (FIG. 2 shows the field stop 27
The opening inside 0,271 is shown in white. ).

As described above, in the microscope of this embodiment, since the left and right secondary images are formed in the adjacent area on the imaging surface of the single CCD 116, the boundary between the left and right images on the CCD 116 is clearly defined. It is necessary to prevent overlapping of images.
For this reason, the three-dimensional microscope 101 is provided with field stops 270 and 271 at the position of the primary image. By making the straight edge of the substantially semicircular aperture function as a so-called knife edge and transmitting only the light flux inside it, the CCD
The boundary between the left and right images on 116 can be clarified.

The primary images formed on the field stops 270 and 271 are re-imaged by the relay optical systems 240 and 250 to become secondary images.
Left and right are reversed. Therefore, the knife edge that defines the outside in the left-right direction at the position of the primary image defines the inside in the left-right direction at the position of the secondary image, that is, the boundary between the left and right images.

Each of the relay optical systems 240 and 250 has the function of re-imaging the primary image formed by the zoom optical systems 220 and 230 as described above.
41, 242, 243, 251, 252, and 253, respectively.

As shown in FIGS. 6 and 7, one relay optical system 240 includes a first lens 241 composed of a single positive meniscus lens, and a second lens 242 having a positive power as a whole. , And a third lens 243 composed of a single biconvex lens. Among them, the first lens 241 and the second lens 242 have their entire object-side focal points coincident with the image plane of the primary image formed by the zoom optical system 220 (the same plane as the field stop 270). The third lens 243 is a second lens 2
The parallel light emitted from 42 is converged on the imaging surface of CCD 116. A pentaprism 272 for deflecting the optical path at right angles is disposed between the first lens 241 and the second lens 242, and the second lens 242 and the third lens 2
A brightness stop 244 for adjusting the amount of light is provided between the aperture stop 43.

The other relay optical system 250 has the same configuration as the above-described relay optical system 240, and includes first to third lenses 251, 252, and 253. The first and second lenses 251 and 252 are connected to each other. A pentaprism 273 is disposed between the second lens 252 and the third lens 25.
3, a brightness stop 254 is provided.

The divergent light transmitted through each of the field stops 270 and 271 is again converted into substantially parallel light by the first lens 241 and 251 and the second lens 242 and 252 of the relay optical system, and transmitted through the brightness stop 244 and 254. After that, the image is formed again by the third lenses 243 and 253 to form a secondary image.

By disposing the pentaprisms 272 and 273 in the relay optical systems 240 and 250, the optical axes of the zoom optical systems 220 and 230 and the relay optical systems 240 and 25 are arranged.
It can be provided by bending the zero optical axis. Thus, the overall length of the photographing optical system (a pair of photographing optical systems) 200 in the optical axis direction of the close-up optical system 210 can be shortened.

A predetermined base line length is required between the optical axes of a pair of left and right photographing optical systems in order to obtain a stereoscopic effect by stereoscopic viewing. On the other hand, the distance between the centers of the left and right imaging regions defined by the boundary line set at the center on the imaging surface of the CCD 116 is sufficiently shorter than the base line length formed by both imaging optical systems, In order to form secondary images in adjacent left and right imaging regions, it is necessary to make the distance between optical axes guided to the imaging surface smaller than the above-described base line length.

Therefore, by shifting the optical axes Ax2 and Ax3 of the relay optical systems 240 and 250 inward by the convergence shifting prism 260, an image is formed on the imaging surface of the same CCD 116 while securing a predetermined base line length. Is possible. Here, both photographing optical systems (zoom optical systems 220 and 23)
0 and the optical axis of the relay optical system 240, 250) are separated from each other by a straight line of the base line length, which coincides with the left-right direction which is the longitudinal direction of the imaging surface of the CCD 116.

As shown in FIGS. 2, 6 and 9, a pair of optical axis shift prisms 261 and 262 having a symmetrical pentagonal prism shape are formed by a CCD as shown in FIGS.
It is arranged symmetrically with respect to a boundary surface Bo1 erected vertically along the boundary line between the left and right imaging regions on the imaging surface of 116, and is fixed with a gap of about 0.1 mm. Have been.

Each of the optical axis shift prisms 261 and 262 is
As shown in FIGS. 2 and 9, two first reflection surfaces 261 a and 262 a and second reflection surfaces 261 b and 262 b inclined 45 ° with respect to the boundary surface Bo 1, and an incident light perpendicular to the boundary surface Bo 1. End surfaces 261c and 262c and injection end surface 26
1d, 262d, 135 ° adjacent to the second reflecting surfaces 261b, 262b and the exit end surface 261
d and 262d at 90 ° to be in a direction parallel to the boundary surface Bo1.
262e. That is, each of the optical axis shift prisms 261 and 262 has a shape equivalent to a prism having a parallelogram planar shape cut off at the joint surfaces 261e and 262e.

The left and right object lights from the relay optical systems 240 and 250 enter from the incident end surfaces 261c and 262c of the optical axis shift prisms 261 and 262, respectively, and reach the boundary surface Bo1 by the outer first reflection surfaces 261a and 262a. The second reflection surfaces 261b and 262b further reflected toward the inside
Is reflected again in the same traveling direction as that at the time of incidence, exits from the exit end surfaces 261d and 262d, and is
The light enters the CD camera 102. As a result, the left and right object lights are shifted so as to approach the boundary surface Bo1 without changing their traveling directions, and form secondary images on the same imaging surface of the CCD 116, respectively.

In the secondary images formed in the left and right image pickup areas on the image pickup surface, portions formed at portions near the boundary surface Bo1 are the second reflection surfaces 261b and 261b of the optical axis shift prisms 261 and 262. Since a structure equivalent to 262b being cut off at the joining surfaces 261e and 262e, respectively, a part of the family light to be converged at that portion is missing, so that the light transmitted through the relay optical systems 240 and 250. A boundary surface B in which all the family rays are reflected by the second reflecting surface 262b and converge.
It becomes darker than the part formed at a part distant from o1. That is, the secondary image formed in the left and right imaging regions has the boundary surface Bo1 unless the density distribution filters 1 and 2 described above are provided.
There is a gradient in the illuminance distribution that the portion far from the illuminance is bright and gradually darkens near the boundary surface Bo1.

Therefore, the gradient of the illuminance distribution which would occur in the secondary image is canceled out on the optical paths of the left and right object lights passing through the relay optical systems 240 and 250, so that the illuminance of the secondary image is evenly reduced. Density distribution filters 1 and 2 are provided beforehand to give the distribution of the luminous flux density to each subject light.

FIG. 10 is a front view of the density distribution filters 1 and 2. Each of the density distribution filters 1 and 2 is an ND filter formed by applying an achromatic coating to a substrate made of a square transparent plate with a predetermined transmittance gradient in one axial direction (the horizontal direction in FIG. 10). It is. As shown in FIG. 10, this coating is formed with a transmittance that reduces the amount of transmitted light by about half, up to about half of the left side with respect to the uniaxial direction on the substrate, and has a center on the substrate. The transmittance is gradually increased from the vicinity to the right end side.

The density distribution filters 1 and 2 correspond to the incident end surfaces 261 c and 262 of the optical axis shift prisms 261 and 262.
c, right and left relay optical systems 24
They are arranged so as to be perpendicular to the optical axes Ax2 and Ax3 of 0,250. At this time, the density distribution filters 1 and
2 is arranged so that the direction in which the gradient of the transmittance is formed is the same as the base length direction of the photographing optical system 200, and as shown in FIG. Are arranged so that the side that is located is on the boundary surface Bo1 side. Therefore, among the light rays of the subject light that enter each imaging region and form an image, the similar light rays converging near the boundary surface Bo1 mainly pass through the high transmittance portions of the density distribution filters 1 and 2, and A similar light ray converging to a portion distant from the surface Bo1 is attenuated by mainly transmitting the low transmittance portions of the density distribution filters 1 and 2.

Therefore, each subject light transmitted through the density distribution filters 1 and 2 is given a light flux density distribution for equalizing the illuminance of the secondary image, and after being reflected by the converging prism 260, the uniform illuminance is obtained. The respective secondary images are formed on the imaging surface.

<Operation of Embodiment> With the above-described configuration, the density distribution filters 1 and 2 have a structure equivalent to that of the optical axis shift prisms 261 and 262 being cut off by the joining surfaces 261e and 262e, respectively. Otherwise, the gradient of the illuminance distribution generated in the secondary image is
The density distribution filters 1 and 2 having predetermined transmittance gradients disposed on the optical paths 0 and 250 cancel each other out in advance, and each subject light forms a secondary image with uniform illuminance in an imaging area on the imaging surface. Form. Left and right images 120a and 120b obtained by capturing these left and right secondary images are also
It has a uniform illuminance, and can display balanced left and right images on the LCD panel 120 and the monitor screen 114. When the main surgeon looks into the stereoscopic viewer 113, natural and clear stereoscopic vision is obtained. Can be.

[0077]

Embodiment 2 The second embodiment of the present invention is the same as the first embodiment.
Compared with the embodiment, only the position where the density distribution filter is arranged is different, and other configurations are common. FIG. 11 is an optical configuration diagram of the second embodiment.

As shown in FIG. 11, the density distribution filters 1a and 2a are optical axis shift prisms 261 and 26.
The optical axes Ax2 and Ax2 of the left and right relay optical systems 240 and 250 are respectively disposed immediately after the two emission end surfaces 261d and 262d.
It is arranged to be perpendicular to Ax3. At this time, the density distribution filters 1a and 2a are arranged so that the direction in which the gradient of the transmittance is formed is the same as the base length direction of the imaging optical system 200, and the transmittance is formed high. Are arranged such that the side that is facing comes to the boundary surface Bo1 side. For this reason, among the subject light that enters each imaging region and forms an image, the similar light rays converging in the vicinity of the boundary surface Bo1 pass through the high transmittance portions of the density distribution filters 1a and 2a, and separate from the boundary surface Bo1. The homologous rays converging on the converged portion are reflected by the density distribution
The light is dimmed by transmitting a portion having a low transmittance in. Therefore, each subject light transmitted through the density distribution filters 1a and 2a is reflected by the convergence shifting prism 260, and then forms a secondary image having uniform illuminance on the imaging surface.

Furthermore, in the second embodiment, the image plane (secondary image) of the image forming surface (ie, the CCD 1) is larger than in the first embodiment.
The density distribution filters 1 and 2 are arranged close to the 16 imaging planes. Therefore, the range over which the similar light beams converging on the individual points on the imaging surface of the CCD 116 pass through the density distribution filters 1 and 2 is narrower than in the case of the second embodiment. Becomes larger, and the luminous flux density distribution given to the subject light becomes clearer.

The other configuration in the second embodiment is as follows.
The description is omitted because it is the same as that of the first embodiment.

[0081]

Embodiment 3 The third embodiment of the present invention is the same as the first embodiment.
Compared with the embodiment, only the position where the density distribution filter is arranged is different, and other configurations are common. FIG. 12 is an optical configuration diagram of the third embodiment.

As shown in FIG. 12, the density distribution filters 1b and 2b are disposed immediately before the apertures of the field stops 270 and 271, respectively, and the left and right relay optical systems 240 and 25 are arranged.
It is arranged to be perpendicular to the 0 optical axes Ax2 and Ax3. At this time, the density distribution filters 1b and 2b
Means that the direction in which the gradient of the transmittance is formed is the imaging optical system 2
00 is arranged in the same direction as the base line length direction and its transmittance is formed low.
o1 side (that is, the one with the higher transmittance is the field stop 270,
271 (knife edge side). For this reason, among the subject light that enters each imaging region and forms an image, the homologous rays that converge once near the knife edge of the field stop 270 or 271 and then converge again near the boundary surface Bo1 are the density distribution filters 1a and The homologous rays that pass through the high transmittance portion 2a and converge once at a position distant from the knife edge and then converge at a portion distant from the boundary surface Bo1 have low transmittance portions in the density distribution filters 1b and 2b. Is dimmed by transmitting light. Therefore, each subject light transmitted through the density distribution filters 1b and 2b is reflected by the converging prism 260, and then forms a secondary image having uniform illuminance on the imaging surface.

Moreover, in the third embodiment, the second
The density distribution filters 1 and 2 are arranged closer to the image forming plane of the image (primary image) (that is, the field stops 270 and 271) than in the case of the embodiment. Therefore, the effects of the density distribution filters 1 and 2 become greater, and the luminous flux density distribution given to the subject light becomes clearer.

The other configuration of the third embodiment is as follows.
The description is omitted because it is the same as that of the first embodiment.

[0085]

Embodiment 4 The fourth embodiment of the present invention is the same as the first embodiment.
Compared with the embodiment, only the position where the density distribution filter is arranged is different, and other configurations are common. FIG. 13 is an optical configuration diagram of the fourth embodiment.

As shown in FIG. 13, the density distribution filters 1c and 2c are disposed immediately after the apertures of the field stops 270 and 271, respectively, and the left and right relay optical systems 240 and 25 are arranged.
It is arranged to be perpendicular to the 0 optical axes Ax2 and Ax3. At this time, the density distribution filters 1c and 2c
Means that the direction in which the gradient of the transmittance is formed is the imaging optical system 2
00 is arranged in the same direction as the base line length direction, and the portion where the transmittance is low is located on the boundary surface Bo1 side (that is, the one with the higher transmittance is the field stop 27).
0,271 knife edge side). Therefore, among the subject light that enters each imaging region and forms an image, homologous rays that once converge near the knife edge of the field stops 270 and 271 and then converge near the boundary surface Bo1 are the density distribution filters 1c and 2c. Are transmitted through a portion having a high transmittance, and are converged once at a position distant from the knife edge and then converge again at a portion distant from the boundary surface Bo1.
The light is dimmed by transmitting the low transmittance portion in c. Therefore, each subject light transmitted through the density distribution filters 1c and 2c is reflected by the convergence shifting prism 260, and then forms a secondary image having uniform illuminance on the imaging surface.

Further, in the fourth embodiment, the second
The density distribution filters 1 and 2 are arranged closer to the image forming plane of the image (primary image) (that is, the field stops 270 and 271) than in the case of the embodiment. Therefore, the effects of the density distribution filters 1 and 2 become greater, and the luminous flux density distribution given to the subject light becomes clearer.

The other configuration of the fourth embodiment is as follows.
The description is omitted because it is the same as that of the first embodiment.

As a development of the fourth embodiment and the third embodiment described above, the density distribution filters 1 and 2 may be integrated into the apertures of the field stops 270 and 271. With this configuration, the position where the image (primary image) is formed and the position where the light flux density is adjusted by the density distribution filters 1 and 2 match, so that the illuminance distribution in the secondary image can be corrected more precisely.

[0090]

Embodiment 5 The fifth embodiment of the present invention is the same as the first embodiment.
Compared with the embodiment, the optical axes Ax2,2 of the relay optical systems 240,250 are located at the positions where the density distribution filters are arranged.
An aperture stop eccentric with respect to Ax3 is arranged, and other configurations are common. FIG. 14 is an optical configuration diagram of the fifth embodiment. 15 to 17 are front views showing the states in which the aperture stop 3 is stopped down in order, as viewed from the incident side of the subject light passing through the relay optical system 240 to the exit side.

Each of the aperture stops 3 and 4 is connected to each of the relay optical systems 24.
Brightness diaphragms 244, 254 provided in 0, 250
As shown in FIG. 14, each of the optical axis shift prisms 26 has a device capable of expanding and contracting the inner diameter of the opening.
The optical axes A of the left and right relay optical systems 240 and 250 are disposed immediately before the incident end surfaces 261c and 262c of the left and right relay optical systems 240 and 250, respectively.
x2, Ax3 with respect to the central axis A of the aperture stops 3, 4
x′1 and Ax′2 are arranged so as to be parallel. However, as shown in FIGS. 14 and 15, the central axes Ax′1 and Ax′2 of the aperture stops 3 and 4 are connected to the relay optical systems 240 and 2 respectively.
The optical axes Ax2 and Ax3 are eccentric from the center of each of the left and right imaging regions on the imaging surface toward the boundary surface Bo1.

Then, the aperture stop 3 and the aperture stop 4 are moved to FIG.
When the aperture is gradually stopped down from the state of FIG. 5 to the state of FIG. 17 through the state of FIG.
Since it is provided eccentrically with respect to Ax3, the boundary surface Bo1 of the subject light that enters each imaging region and forms an image
The similar rays converging to the vicinity are hardly vignetted by the aperture stops 3 and 4, but the similar rays converging to a part distant from the boundary surface Bo1 are partially vignetted by the aperture stops 3 and 4. The luminous flux as a whole becomes thinner and CC
The portion of D116 on the imaging surface that is distant from boundary surface Bo1 gradually darkens. The assembling operator appropriately adjusts the aperture stop amounts of the aperture stops 3 and 4 so that the illuminance of the secondary image formed on the imaging surface is formed uniformly.

In this way, the aperture stops 3 and 4 eccentrically arranged with respect to the optical axes Ax2 and Ax3 reduce the brightness of a portion of the secondary image formed on each imaging surface, which is distant from the boundary surface Bo1. Thus, the illuminance can be made approximately the same as the vicinity of the boundary surface Bo1.

By setting the locations of the aperture stops 3 and 4 sufficiently away from the final surfaces of the relay optical systems 240 and 250, the position of the aperture stop 3 and 4 can be reduced from the boundary Bo1 without affecting the similar rays converging near the boundary Bo1. A part of the homologous rays converging on the separated part can be removed. Further, the installation positions of the aperture stops 3 and 4 are changed to an image forming plane (secondary image) (CCD 11).
6 is sufficiently separated from the boundary surface Bo1.
Only some of the cognate light rays that converge at a site away from can be quenched.

The other configuration in the fifth embodiment is as follows.
The description is omitted because it is the same as that of the first embodiment.

[0096]

Embodiment 6 The sixth embodiment of the present invention is the same as the fifth embodiment.
As compared with the embodiment, only the position where the aperture stop is arranged is different, and other configurations are common. FIG. 18 is an optical configuration diagram of the sixth embodiment.

As shown in FIG. 18, the aperture stop 3
a, 4a are the objective optical systems 220, 230 and the field stop 27;
0,271, and the central axes Ax'1, Ax'2 of the aperture stops 3a, 4a are parallel to the optical axes Ax2, Ax3 of the left and right objective optical systems 220, 230, respectively. It is arranged to become. However, as shown in FIG. 18, the central axes Ax'1 and Ax'2 of the aperture stops 3a and 4a.
Represents a boundary Bo with respect to the optical axes Ax2 and Ax3 of the objective optical systems 220 and 230 from the center of the left and right imaging regions on the imaging surface
It is eccentric away from 1.

When the aperture stops 3a and 4a are gradually stopped down, the aperture stops 3a and 4a are shifted to the optical axes Ax2 and Ax.
3, the similar rays converging near the boundary surface Bo1 out of the subject light that enters each imaging region and forms an image are almost eclipsed by the aperture stops 3a and 4a. Although there are no similar rays converging on a part distant from the boundary surface Bo1, a part of the rays is similar to the aperture stops 3a and 4a.
The vignetting becomes thinner as a whole,
The portion on the imaging surface of the CCD 116 away from the mirror interface Bo1 gradually darkens. The assembling operator appropriately adjusts the aperture amounts of the aperture stops 3a and 4a so that the illuminance of the secondary image formed on the imaging surface is formed uniformly.

As described above, the aperture stops 3a and 4a eccentrically arranged with respect to the optical axes Ax2 and Ax3 reduce the brightness of a portion of the secondary image formed on each imaging surface, which is distant from the boundary surface Bo1. Thus, the illuminance can be made approximately the same as the vicinity of the boundary surface Bo1.

By setting the installation positions of the aperture stops 3a and 4a sufficiently away from the final surfaces of the objective optical systems 220 and 230, the position of the aperture stop 3a and 4a can be reduced from the boundary surface Bo1 without affecting the similar rays converging near the boundary surface Bo1. A part of the homologous rays converging on the separated part can be removed. Also, by setting the installation positions of the aperture stops 3a and 4a sufficiently away from the image forming plane (the positions of the field stops 270 and 271) of the image (primary image),
Only a part of the family rays converging on a portion distant from the boundary surface Bo1 can be reduced.

The other configuration of the sixth embodiment is as follows.
The description is omitted because it is the same as that of the fifth embodiment.

[0102]

Embodiment 7 The seventh embodiment of the present invention is the same as the fifth embodiment.
As compared with the embodiment, only the position where the aperture stop is arranged is different, and other configurations are common. FIG. 19 is an optical configuration diagram of the seventh embodiment.

As shown in FIG. 19, the aperture stop 3
b, 4b are the field stops 270, 271 and the relay optical system 2
The central apertures Ax'1 and Ax'2 of the aperture stops 3b and 4b are parallel to the optical axes Ax2 and Ax3 of the left and right relay optical systems 240 and 250, respectively. Are located in However, as shown in FIG. 19, the central axes Ax′1, Ax′2 of the aperture stops 3b, 4b.
Are the optical axes Ax2 and Ax3 of the relay optical systems 240 and 250.
Is eccentric in a direction away from the boundary surface Bo1 from the center of each of the left and right imaging regions on the imaging surface.

When the aperture stops 3b and 4b are gradually stopped down, similar rays converging in the vicinity of the boundary surface Bo1 out of the subject light incident on each imaging region and forming an image are transmitted through the aperture stops 3b and 4b. Since it is provided eccentrically with respect to the optical axes Ax2 and Ax3, there is almost no vignetting by the aperture stops 3b and 4b. Aperture 3b, 4b
The vignetting becomes thinner as a whole,
The portion on the imaging surface of the CCD 116 away from the boundary surface Bo1 gradually darkens. The assembling operator appropriately adjusts the aperture amounts of the aperture stops 3b and 4b so that the illuminance of the secondary image formed on the imaging surface is formed uniformly.

As described above, the aperture stops 3b and 4b arranged eccentrically with respect to the optical axes Ax2 and Ax3 reduce the brightness of the portion of the secondary image formed on each imaging surface, which is distant from the boundary surface Bo1. Thus, the illuminance can be made approximately the same as the vicinity of the boundary surface Bo1.

It is to be noted that the installation places of the aperture stops 3b and 4b are sufficiently separated from the object side surfaces of the relay optical systems 240 and 250 so that the similar rays converging in the vicinity of the boundary surface Bo1 are not affected. A part of the homologous rays converging on the separated part can be removed. Also, by setting the installation positions of the aperture stops 3b and 4b sufficiently away from the image forming plane (the positions of the field stops 270 and 271) of the images (primary images), the positions on the imaging surface of the CCD 116 away from the boundary surface Bo1 are increased. Only some of the converging homologous rays can be quenched.

The other configuration of the seventh embodiment is as follows.
The description is omitted because it is the same as that of the fifth embodiment.

[0108]

[Eighth Embodiment] The eighth embodiment of the present invention is the same as the first embodiment.
Compared with the embodiment, a slide diaphragm is provided at a position where the density distribution filter is disposed, to restrict each subject light transmitted through each relay optical system 240, 250 from one direction toward the optical axes Ax2, Ax3. , And other configurations are common. FIG. 20 is an optical configuration diagram of the eighth embodiment. 21 to 23 sequentially show states in which the slide diaphragm 5 is narrowed down toward the optical axis Ax2. FIG. 21 is a front view of the slide diaphragm 5 when viewed from the exit side of the subject light passing through the relay optical system 240 to the incident side. FIG.

As shown in FIG. 20, the slide diaphragms 5 and 6 are disposed immediately before the incident end surfaces 261c and 262c of the optical axis shift prisms 261 and 262, respectively, and the light of the relay optical systems 240 and 250 on the left and right sides. It is arranged to be perpendicular to the axes Ax2 and Ax3. 20 and 21
As shown in the figure, the slide stop 5 is a rectangular flat plate, and the optical axis Ax2 of the relay optical system 240 and the boundary surface Bo1.
21 to 23, and is supported in the cylinder so that subject light can be reduced while sliding toward the optical axis Ax2 of the relay optical system 240, as shown in FIGS. The slide stop 6 is also disposed at a position away from the optical axis Ax3 of the relay optical system 250 and the boundary surface Bo1, so that the subject light can be stopped while sliding toward the optical axis Ax3 of the relay optical system 250.
It is supported inside the cylinder.

When the slide diaphragm 5 and the slide diaphragm 6 are gradually stopped down from the state shown in FIG. 21 to the state shown in FIG. 23 through the state shown in FIG. 22, each object light which enters each imaging area and forms an image is obtained. Of the homologous rays converging near the boundary Bo1, there is almost no vignetting by the slide stops 5 and 6, but the homologous rays converging at a portion distant from the boundary Bo1 have a part thereof. As a result, the overall luminous flux becomes thin, and the CCD 11
The portion of the image pickup surface 6 apart from the boundary surface Bo1 gradually becomes darker. The assembling operator appropriately adjusts the amount of stop of the slide diaphragms 5 and 6 so that the illuminance of the secondary image formed on the imaging surface is uniformly formed.

As described above, the brightness of the portion of the secondary image formed on each imaging surface, which is distant from the boundary surface Bo1, is reduced by the slide diaphragms 5, 6 arranged eccentrically with respect to the optical axes Ax2, Ax3. Thus, the illuminance can be made approximately the same as the vicinity of the boundary surface Bo1.

By setting the positions of the slide diaphragms 5 and 6 far enough away from the final surfaces of the relay optical systems 240 and 250, it is possible to reduce the distance from the boundary surface Bo1 without affecting similar rays converging near the boundary surface Bo1. A part of the homologous rays converging on the separated part can be removed. In addition, the installation positions of the aperture stops 5 and 6 are changed to an image forming surface (second image) (CCD 1).
16 imaging plane), the boundary surface Bo
Only some of the cognate rays that converge at sites away from 1 can be quenched.

The other configuration of the eighth embodiment is as follows.
The description is omitted because it is the same as that of the first embodiment.

[0114]

[Embodiment 9] The ninth embodiment of the present invention is the same as the eighth embodiment.
Compared with the embodiment, only the position where the slide diaphragm is arranged is different, and other configurations are common. FIG.
FIG. 2 is an optical configuration diagram of the embodiment.

As shown in FIG. 24, the slide diaphragms 5a and 6a are disposed in the optical path between the field diaphragms 270 and 271 and the objective optical systems 220 and 230, respectively. Are arranged so as to be perpendicular to the optical axes Ax2 and Ax3. As shown in FIG. 24, the slide stops 5a and 6a are rectangular flat plates, and the slide stop 5a is provided with an optical axis Ax of the objective optical system 220.
2 and the boundary surface Bo1, the slide stop 6a
Is disposed between the optical axis Ax3 of the objective optical system 230 and the boundary surface Bo1. The slide diaphragms 5a and 6a are supported in the cylinder so that each subject light can be reduced while sliding toward the optical axes Ax2 and Ax3 of the objective optical systems 220 and 230, respectively.

When the slide diaphragms 5a and 6a are gradually stopped down, the similar light rays converging near the boundary surface Bo1 out of the subject light incident on each imaging region and forming an image,
Although there is almost no vignetting due to the slide stops 5a and 6a, similar rays converging at a portion distant from the boundary surface Bo1 are vignetted by the slide stops 5a and 6a. The upper part away from the boundary surface Bo1 gradually darkens.
The assembling operator appropriately adjusts the stop-down amounts of the slide stops 5a and 6a so that the illuminance of the secondary image formed on the imaging surface is formed uniformly.

In this way, the slide apertures 5a and 6a eccentrically arranged with respect to the optical axes Ax2 and Ax3 reduce the brightness of a portion of the secondary image formed on each imaging surface, which is distant from the boundary surface Bo1. Thus, the illuminance can be made approximately the same as the vicinity of the boundary surface Bo1.

By setting the positions of the slide diaphragms 5a and 6a sufficiently away from the final surfaces of the objective optical systems 220 and 230, the position of the slide stop 5a and 6a can be reduced from the boundary surface Bo1 without affecting the similar rays converging near the boundary surface Bo1. A part of the homologous rays converging on the separated part can be removed. Further, by setting the installation positions of the slide stops 5a and 6a sufficiently away from the image forming plane (the positions of the field stops 270 and 271) of the images (primary images), among the family rays converging to a part distant from the boundary surface Bo1. Only part of the can be Kel.

The other configuration of the ninth embodiment is as follows.
Since it is the same as that of the eighth embodiment, the description is omitted.

[0120]

[Embodiment 10] The tenth embodiment of the present invention differs from the above-described eighth embodiment only in the position at which the slide stop is arranged, and has the other configuration in common. FIG. 25 is an optical configuration diagram of the tenth embodiment.

As shown in FIG. 25, the slide stops 5b and 6b are disposed in the optical path between the field stops 270 and 271 and the relay optical systems 240 and 250, respectively, and the left and right relay optical systems 240 and 250 are provided. Are arranged so as to be perpendicular to the optical axes Ax2 and Ax3. As shown in FIG. 25, the slide stops 5b and 6b are rectangular flat plates, and the slide stop 5b is disposed between the optical axis Ax2 of the relay optical system 240 and the boundary surface Bo1, and the slide stop 6b is , The optical axis Ax3 of the relay optical system 250 and the boundary surface Bo
1 between them. Then, the slide apertures 5b, 6
b denotes the optical axes Ax2 and Ax of the relay optical systems 240 and 250.
Each object light is supported inside the cylinder so that each object light can be reduced while sliding toward 3.

When the slide stops 5b and 6b are gradually stopped down, the similar rays converging near the boundary surface Bo1 out of the subject light incident on each imaging area and forming an image are:
Although almost no vignetting is caused by the slide stops 5b and 6b, similar rays converged on a portion distant from the boundary surface Bo1 are vignetted by the slide stops 5b and 6b. The upper part distant from the imaging surface Bo1 gradually darkens.
The assembling operator appropriately adjusts the amount of stop of the slide stops 5b and 6b so that the illuminance of the secondary image formed on the imaging surface is formed uniformly.

As described above, the brightness of a portion of the secondary image formed on each imaging surface, which is distant from the boundary surface Bo1, is reduced by the slide diaphragms 5b and 6b arranged eccentrically with respect to the optical axes Ax2 and Ax3. Thus, the illuminance can be made approximately the same as the vicinity of the boundary surface Bo1.

By setting the installation positions of the slide diaphragms 5b and 6b sufficiently away from the object side surfaces of the relay optical systems 240 and 250, it is possible to reduce the distance from the boundary surface Bo1 without affecting similar rays converging near the boundary surface Bo1. A part of the homologous rays converging on the separated part can be removed. Also,
By setting the installation positions of the aperture stops 5b and 6b sufficiently away from the image plane (the positions of the field stops 270 and 271) of the images (primary images), one of the similar rays converged on a part distant from the boundary surface Bo1. Only parts can be quenched.

The other structure of the tenth embodiment is the same as that of the eighth embodiment, and the description is omitted.

[0126]

As described above, according to the stereoscopic microscope of the present invention, it is possible to prevent the illuminance distribution of the left and right subject images from being biased due to the left and right subject light being reflected by the reflecting member. And left and right images having uniform brightness are formed on the imaging surface, thereby enabling natural and accurate stereoscopic viewing.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing the overall configuration of a surgery support system incorporating a stereo microscope according to a first embodiment of the present invention.

FIG. 2 is an optical configuration diagram schematically showing an optical configuration in a stereo microscope.

FIG. 3 is an optical configuration diagram schematically showing an optical configuration of a stereoscopic viewer.

FIG. 4 is a plan view of an LCD panel.

FIG. 5 is an external perspective view of a stereo microscope.

FIG. 6 is a perspective view showing the overall configuration of a microscope optical system.

FIG. 7 is a side view showing the overall configuration of the microscope optical system.

FIG. 8 is a front view showing the entire configuration of the microscope optical system.

FIG. 9 is a plan view showing the overall configuration of a microscope optical system.

FIG. 10 is a front view of a density distribution filter.

FIG. 11 is an optical configuration diagram schematically showing an optical configuration in a stereo microscope according to a second embodiment of the present invention.

FIG. 12 is an optical configuration diagram schematically showing an optical configuration in a stereo microscope according to a third embodiment of the present invention.

FIG. 13 is an optical configuration diagram schematically showing an optical configuration in a stereo microscope according to a fourth embodiment of the present invention.

FIG. 14 is an optical configuration diagram schematically showing an optical configuration in a stereo microscope according to a fifth embodiment of the present invention.

FIG. 15 is a front view of an aperture stop.

FIG. 16 is a front view showing a state where the aperture stop is narrowed.

FIG. 17 is a front view showing a state where the aperture stop is narrowed.

FIG. 18 is an optical configuration diagram schematically showing an optical configuration in a stereo microscope according to a sixth embodiment of the present invention.

FIG. 19 is an optical configuration diagram schematically showing an optical configuration in a stereo microscope according to a seventh embodiment of the present invention.

FIG. 20 is an optical configuration diagram showing an outline of an optical configuration in a stereo microscope according to an eighth embodiment of the present invention;

FIG. 21 is a front view of a slide diaphragm.

FIG. 22 is a front view of a state in which the slide aperture is reduced.

FIG. 23 is a front view showing a state where the slide aperture is narrowed.

FIG. 24 is an optical configuration diagram schematically showing an optical configuration in a stereo microscope according to a ninth embodiment of the present invention;

FIG. 25 is an optical configuration diagram showing an outline of an optical configuration in a stereo microscope according to a tenth embodiment of the present invention;

FIG. 26 is an optical configuration diagram of a conventional convergence shifting prism and an imaging surface.

FIG. 27 is a front view of an LCD panel.

FIG. 28 is a diagram showing a conventional convergence shifting prism and an optical configuration on an imaging surface.

[Explanation of symbols]

 1-1c density distribution filter 2-2c density distribution filter 3-3b aperture stop 4-4b aperture stop 5-5b slide stop 6-6b slide stop 7 luminous flux 100 first stand 101 stereo microscope 102 HDTV CCD camera 105 light guide 116 CCD Reference Signs List 200 shooting optical system 240, 250 relay optical system 260 convergence shifting prism 261,262 optical axis shift prism 261a, 262a first reflection surface 261b, 262b second reflection surface 270,271 field stop 280 objective optical system 300 illumination optical system 400 convergence Shifting prism 401, 402 Optical axis shifting prism 401b 'Dashed line 403 CCD color separation prism 410 Vignetting

Claims (15)

[Claims] 1. An image pickup apparatus comprising: a pair of imaging optical systems disposed at a predetermined base length apart from each other in the imaging area of an imaging apparatus; In each of the stereoscopic microscopes that forms an image of the subject and simultaneously captures the image by the imaging device, each of the photographing optical systems includes an objective optical system that forms a primary image of a subject, and a relay that relays the primary image to a secondary image. A relay optical system to form an image,
A first reflecting surface and a second reflecting surface formed in parallel with each other, and the optical axis of the relay optical system is shifted so as to be closer to the optical axis of the other photographing optical system to correspond to the imaging surface. A reflecting member that forms the secondary image in the imaging region by guiding the secondary image to the imaging region; and a portion near the boundary line on the imaging surface, which is disposed on an optical path from the objective optical system to the imaging surface. A stereoscopic microscope, comprising: correction means for substantially passing a light beam converging on the imaging surface and partially reducing a light beam converging on a portion of the imaging surface distant from the boundary line. 2. An end of the second reflection surface of each of the reflection members on the imaging surface side substantially in contact with a boundary surface set perpendicular to the imaging surface along the boundary line. The stereo microscope according to claim 1, wherein: 3. The correcting means is formed in a flat plate shape having a transmission surface, is disposed so as to intersect with an optical axis of the photographing optical system, and has one end to the other end in the direction of the base line length. 3. A density distribution filter formed so that the transmittance increases toward.
The stereo microscope described. 4. A density distribution filter as said correction means,
4. A structure having a predetermined uniform transmittance from one end side to the vicinity of the center in the direction of the base line length, wherein the transmittance is gradually increased from the vicinity of the center to the other end side. The stereo microscope described. 5. A density distribution filter as said correction means,
The stereoscopic microscope according to claim 3, wherein the stereoscopic microscope is arranged near an image forming surface on which an image is formed in the photographing optical system. 6. A density distribution filter as said correction means,
6. The transmission optical system according to claim 5, wherein the transmission optical system is disposed near an image forming surface on which the primary image is formed, and has a higher transmittance on a side remote from the other imaging optical system than on another side. The stereo microscope described. 7. A density distribution filter as said correction means,
6. The transmission optical system according to claim 5, wherein the transmission optical system is disposed near an image forming surface on which the secondary image is formed, and the transmittance of the other imaging optical system is lower than that of the other imaging optical system. The stereo microscope described. 8. The shielding means which is arranged so as to enter the optical path from the side of the optical path so as to shield only a light beam converging on a portion of the imaging surface apart from the boundary line. The stereoscopic microscope according to claim 1, wherein the stereoscopic microscope is a member. 9. The apparatus according to claim 1, wherein the shielding member as the correction means is disposed between an image forming surface on which a primary image is formed by the objective optical system and a final surface of the objective optical system. 8. The stereo microscope according to 8. 10. The relay member as claimed in claim 1, wherein the shielding member is arranged between an image forming surface on which a primary image is formed by the objective optical system and an object side surface of the relay optical system. 8. The stereo microscope according to 8. 11. A relay device according to claim 11, wherein said shielding member is disposed between an image forming surface on which a secondary image is formed by said relay optical system and a final surface of said relay optical system. Item 3. A stereo microscope according to Item 8. 12. The apparatus according to claim 9, wherein said shielding member as said correction means is an aperture stop arranged so that the center of the aperture is decentered from the optical axis of said photographing optical system. The stereo microscope described. 13. A stereo microscope according to claim 12, wherein said aperture stop as said correction means has a stop mechanism for adjusting the inner diameter of the opening. 14. The shielding member according to claim 9, wherein said shielding member as said correcting means is a shielding plate having a flat plate shape with a straight edge formed on one side. Stereo microscope. 15. The stereoscopic microscope according to claim 14, wherein the shielding plate as the correction means has a stop mechanism for sliding the edge toward the optical axis of the photographing optical system.