JPH05323201A - microscope - Google Patents

Abstract

(57) [Summary] [Purpose] The weight of the arm that supports the microscope body is reduced, and the vibration that acts on the microscope is blocked. [Arrangement] A gate-shaped arm 7 for supporting a microscope is installed in an arcuate arch shape so as to straddle the stage 4, and its leg portion 7c.
Is fixed to the base 1. Further, the focusing elevating mechanism 15 is independently suspended at a substantially central position of the span of the arm 7, the extension relay lens barrel 14 is integrally attached to the arm 7 in the longitudinal direction, and the observation lens barrel 13 is directly attached to the arm 7 main body. Attach to.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microscope, and more particularly to a microscope which enables easy visual inspection of a plate-shaped sample such as a large-sized liquid crystal substrate.

[0002]

2. Description of the Related Art In recent years, the display screens of laptop word processors, personal computers, in-vehicle liquid crystal televisions, etc. have become larger and have higher resolutions, and the liquid crystal display substrate that constitutes the display portion has also become larger and the products are expensive. Precision is required. For this reason, a microscope having a stage on which a large plate-shaped sample having a side of 400 mm or more can be placed is required for the visual inspection of products. On the other hand, in order to inspect the state of a large plate-shaped sample such as a wafer or an exposure reticle used also in a semiconductor manufacturing process, various microscopes have been developed in consideration of sample handling and the like.

4 and 5 are a side view and a plan view showing a conventional microscope for inspection of this kind. In the figure,
Reference numeral 50 indicates a base, which is installed horizontally on a stable work table T. A stage 51 is placed and fixed on the upper surface of the base 50. The stage 51 can be slid in the directions orthogonal to the X and Y axis directions, and the position of the sample 52 set on the stage 51 is adjusted roughly and finely.

On the other hand, above the stage 51, a gate-shaped arm 53 is installed so as to straddle the stage 51. As for the shape, as shown in FIG. 5, the planar shape is substantially Y-shaped so that both legs are located at the ends of the base 50, and as shown in FIG. 5, a horizontal beam portion 53a having a long horizontal span is formed. The microscope main body 55 has a gate-like shape composed of diagonal beams 53b located at both ends thereof and a short column portion 53c which is a supporting portion.
It is designed to support the weight of. At this time, the microscope main body 55 can be raised and lowered by the focusing raising and lowering mechanism 54.
It is supported in a cantilevered state by means of 3 and can be raised and lowered by driving the focusing raising and lowering mechanism 54.

The microscope main body 55 has an objective lens 56 for observing a sample 52 such as a substrate mounted on the stage 51.
An electric revolver unit 57 that holds a plurality of objective lenses 56 and can switch the lenses by electric operation, and a reflection illuminator 58 that illuminates the sample surface via the objective lenses 56.
And an observation mirror positioned above the end of the base 50 by declining the light beam so that the vertical optical axis A1 of the image-forming light beam from the objective lens 56 becomes a horizontal light beam oriented in the Y-axis direction of the stage 51. An extension relay barrel 60 for accommodating the relay optical system A2 extending to the position of the barrel 59, and this extension relay barrel 60
For observation 5 equipped with an eyepiece lens 61 attached to the distal end of the
It is composed of 9 and 9. Therefore, in the microscope body 55, the vertical optical axis A1 from the objective lens 56 is deviated at a right angle by a prism or reflecting mirror (not shown), is guided to the horizontal optical axis A2 of the relay optical system, and is further upward by a prism or reflecting mirror (not shown). It is set so as to be deviated at a right angle toward the eyepiece and enters the eyepiece lens 61 via the inside of the observation lens barrel 59.

[0006]

By the way, in order to inspect a larger sample, the stage 51 on which the sample can be placed must be provided on the base 50. Therefore, the microscope main body constructed as described above. At 55, the optical path length of the relay optical system becomes long in proportion to the size of the stage 51, and the length of the extension relay barrel 60 that accommodates this relay optical system also becomes long accordingly.

Further, the above-mentioned microscope body 55 has a focusing elevating mechanism 54 at a substantially central position of the extension relay barrel 60.
The observation lens barrel 59 is attached to one end of the extension relay lens barrel 60, and the reflection illumination device 58 is attached to the other end.
And the electric revolver unit 57 are connected. Since these are heavier than the observation lens barrel 59, the structure is such that the position of the center of gravity of the microscope main body 55 substantially coincides with the supporting position, and the overall structural system is balanced.

However, since the structural system which is relatively long in the horizontal direction is supported at a substantially central position of the horizontal beam as described above, the horizontal beam of the arm easily bends and is greatly affected by the bending and the stage moves. For example, the microscope main body supported by the arm is apt to vibrate because it is sensitive to vibrations generated during work such as time and external vibrations such as microtremor in the environment surrounding the examination room. For this reason, there is a problem that the microscope image shakes during observation, causing an image shift of the observation image, which interferes with the inspection.

Further, since the heavy microscope main body is supported by the focusing elevating mechanism which is a movable member, a lock mechanism or the like is provided to the focusing elevating mechanism so that the microscope body does not descend due to its own weight during observation. There is also a problem that it needs to be added, the structure is complicated, and the operability is deteriorated.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the conventional technique and to provide a microscope having a structure capable of reducing the influence of vibration and the like during the operation of the microscope.

[0011]

In order to achieve the above object, the present invention provides a base, a stage fixed on the base and movable along a predetermined guide member, and fixed to the base. A gate-shaped arm that is installed so as to straddle the stage, an objective lens that is supported by a focusing elevating mechanism that is fixed to the arm so as to be able to move up and down, and that focuses on a sample that is placed on the stage; In a microscope having a deflecting optical system for deflecting the image-forming light beam in a predetermined direction, and a relay optical system for extending the optical path deflected by the deflecting optical system and guiding it to the observation lens barrel optical system. Is characterized by having a curved arch shape.

At this time, the gate-shaped arm has an arcuate arch shape, the focusing elevating mechanism is suspended at a substantially apex position of the arc, and an extension relay barrel for accommodating the relay optical system is longitudinally arranged. It is preferable that the observation lens barrel, which is integrally attached and accommodates the observation lens barrel optical system, is directly attached to the arm body.

[0013]

According to the present invention, since the gate-shaped arm for supporting the microscope is formed into a curved arch shape and is installed so as to straddle the stage and its legs are fixed to the base, the bending generated at the center portion of the span of the arm. The moment can be kept to a minimum, which makes it possible to produce almost no bending and to minimize the effect of external vibrations.

Further, by making the gate-shaped arm particularly arcuate arch-shaped, it is possible to reduce the member thickness without generating a bending moment, and to stabilize the arm stress state. By independently suspending the focusing elevating mechanism at approximately the apex position of the arc, the extension relay lens barrel is integrally attached to the arm in the longitudinal direction, and the observation lens barrel is directly attached to the arm body, Since the focusing elevating mechanism and the reflection illuminating device can be supported at substantially the center of gravity of the arm, and the focusing elevating mechanism and the extension relay lens barrel can be separated and fixed to the arm, the microscope main body overhangs the arm. It is possible to create a structure system without parts, eliminate external vibration that acts on the microscope main body and vibration that occurs from the movable part of the microscope itself during observation, and thus the image shift of the observed image It is possible to prevent.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a microscope according to the present invention will be described below with reference to FIG.
2 and FIG. 2. FIG. 1 shows a side view of a microscope according to the invention. In the figure, reference numeral 1 indicates a base, which is installed horizontally on the work table T. In this embodiment, the work table T is internally provided with a vibration isolation mechanism such as an air servo, and the vibration isolation mechanism can block external vibration. In addition, a light source for illumination and a stabilizing device therefor are housed in the base 1, and the objective lens 2 of the microscope main body 2
Illumination light can be led up to the reflection illumination device 3 mounted right above through an optical fiber cable (not shown). A transillumination device is also provided in the base 1 so that the substrate can be observed by both illumination systems.

Further, a stage 4 is provided on the upper surface of the base 1.
Is placed and fixed. A sample holder (not shown) is mounted on the stage 4, and the plate holder such as a liquid crystal substrate to be observed can be fixed at a predetermined position by the sample holder. The stage 4 is slidably mounted on guide rails 5 and 6 arranged in two layers in the X and Y axis directions orthogonal to each other, and is moved by a manual handle and a DC motor (not shown).

On the other hand, a gate-shaped arm 7 is installed so as to straddle the stage 4 from the front side on the observer side to the rear side. The gate-shaped arm 7 has a gentle arc shape with a large radius from the span center portion 7a to both shoulder portions 7b along the Y-axis direction of the above-mentioned stage, and through the rubbed portion of the shoulder portion 7b having a small radius of curvature. Almost vertical side wall 7 at the lower end
c is configured. The lower end of the side wall 7c is fixed to the base 1 with a screw or the like (not shown). Further, as shown in FIG. 2, the side wall 7c has a planar shape.
Has a substantially V-shape that is located at both ends of the base 1. It should be noted that there is no problem structurally even if the plane shape of the gate-shaped arm is V-shaped or Y-shaped.

Further, the arm 7 of this embodiment is made of an integral type aluminum alloy casting, and the wall thickness of the member constituting the shell is designed to be about 12 mm.
Further, as shown in FIG. 1, ribs having a predetermined width are formed on the end surface 7d.

On the other hand, the constituent members of the microscope optical system 10 are an objective lens 2 for observing a plate-shaped sample placed on the stage 4, and an electric revolver which holds a plurality of objective lenses 2 and which can be switched by electric operation. The unit 11, the reflection illuminating device 3 that illuminates the sample surface via the objective lens 2, and the observation lens barrel 13 that is positioned above the vertical optical axis A1 of the image-forming light beam from the objective lens 2 further above the end of the arm 7. Extension relay barrel 14 for accommodating the relay optical system A2 extending to the position
And an observation lens barrel 13 connected to the tip of the extension relay lens barrel 14 and fixed to the upper part of the arm and equipped with an eyepiece lens 12.
It consists of and.

Of these, the reflection illuminator 3 and the electric revolver unit 11 connected to the reflection illuminator 3 are suspended from a substantially central position of the arm 7 via a focusing elevating mechanism 15. The reflection illumination device 3 is housed in a rectangular parallelepiped housing as shown in FIGS. 1 and 2, and a hanging point is provided at a substantially central position of the housing, so that the lifting / lowering mechanism 15 for focusing can smoothly move up and down. It will be possible. As a function of the reflective illumination device 3, illumination light guided from an unillustrated light source in the base 1 through an optical fiber is used for the objective lens 2.
The sample is illuminated through the inside of the objective lens 2 by being reflected toward the objective lens 2 by a half mirror (not shown) installed immediately above the position.

Further, the focusing elevating mechanism 15 has an outer cylindrical portion 15a fixed to the reflection illuminating device 3 side, and an inner cylindrical portion 15b fixed to the outer cylindrical portion 15a and the arm 7 side which is nested.
Which is not shown and is housed in the inner cylindrical portion 15b.
The outer cylinder portion 15a can be moved up and down by a C motor via a drive transmission portion such as a gear train. Further, the lens barrel 16 through which the vertical optical axis A1 of the image-forming light beam from the objective lens 2 passes is also nested, and the outer tube portion 16a moves up and down to freely expand and contract, and the tube length can be freely set. In addition, a ring-shaped blind member is attached to the outer circumference of the inner cylindrical portion 15b so as to block stray light from the outside.

Further, near the intersection of the vertical optical axis A1 with the arm center position 7a immediately above the lens barrel 16, there is provided a prism system 20 which constitutes a deflecting optical system capable of switching optical paths. The prism system 20 includes a total reflection deflection angle prism 20A that deviates the optical axis toward the observation lens barrel 13 and a light beam from the objective lens 2 to a photographic straight tube 21 provided at a central position 7a of the arm 7. Half mirror (not shown) that divides the light beam of the above and the light beam to the observation lens barrel 13 at a predetermined division ratio, and a laser (not shown) that is installed at the position of the straight tube 21 for photography and performs repair work of the liquid crystal substrate surface. Cylindrical glass (not shown) for passing the laser light of the repairing device
It consists of and. These prisms can be easily switched by the switching lever 22.

Here, of the prism system 20 described above, the structure of the observation optical system in which the optical axis is deviated by the total reflection declination prism and observation is performed by the observation lens barrel 13 will be described as an example. The image forming light beam of the objective image from the objective lens 2 passes through a half mirror (not shown) in the reflection illuminating device 3, and the first deflection angle prism 20 corresponding to the total reflection deflection angle prism of the prism system 20.
As shown in FIG. 1 and FIG. 2A, the deflection angle α ° and the depression angle β
Declined by °. Further, in order to extend this deviated observation optical path to the position of the observation lens barrel 13, the extension relay lens barrel 1
4 is integrally fixed along the lower surface of the arm 7. A plurality of relay lens groups are housed inside the extension relay barrel 14 to form a relay optical system with a predetermined intermediate magnification. The light beam whose optical path is extended by this relay optical system is the second light beam which is further disposed at the end of the extended relay lens barrel 14.
Is deflected vertically upward by the deflection angle prism 23, passes through the observation lens barrel 13, and reaches the eyepiece lens 12. As a result, the objective image at the objective lens 2 at the substantially central position of the stage 4 can be observed as an enlarged observation image at the eyepiece lens 12 provided at the end position of the base 1.

A step portion 7e is formed on a part of the arm 7,
The observation lens barrel 13 is directly fixed to the step 7e.
Thereby, the eye point of the eyepiece lens 12 can be lowered, and the operator can inspect the substrate and the like in a comfortable posture. At this time, the height of the eye point of the eyepiece 12 from the lower surface of the base 1 is preset based on the data of the body shape of the operator, and the arch of the arm 7 is considered in consideration of the optical distance determined by each optical system. It is preferable to determine the radius.

If the radius of curvature is increased so that the arch portion is relatively flat, the up-and-down stroke of the objective lens 2 becomes small. Therefore, the radius of curvature is the reflection illumination device 3 and the electric revolver unit 11 of the objective lens 2. It is preferable to set in consideration of the arrangement space. The shape is not limited to the arcuate arch, and various quadratic curves such as a part of a flat ellipse may be applied.

As described above, in this embodiment, the arm 7 is formed in an arcuate arch shape, and the focusing raising / lowering mechanism 15 is formed in the arch.
Since the extension relay lens barrel 14 and the observation lens barrel 13 are independently attached, vibrations from the movable part generated during operation of the structural system added to the arm 7 are less likely to propagate to other structural systems of the microscope. can do.

Further, the shape of the arm 7 is not limited to the arch described above, and may be a dome shape having a curvature in two directions. FIG. 3 is a schematic shape view of the arm 7 shown for comparing the arch shape and the dome shape. The figure (a) shows the arch-shaped arm 7 shown in the above-mentioned embodiment, and the figure (b) shows a dome shape having a curvature even in the X-axis direction. Since the strength of the shell is increased by forming such a dome shape, the arm 7
The weight of the member can be reduced.

The focusing lifting mechanism 15 attached to the arm 7 is not limited to the cylindrical telescopic type, and it is needless to say that lifting mechanisms having various structures can be adopted as long as they can perform a stable lifting operation. Nor. Further, although a prism is used as the optical axis deviation means, if an alternative reflecting mirror or the like can achieve the same action, they may be incorporated to form an optical system.

[0029]

As is apparent from the above description, according to the present invention, the arm supporting the microscope main body has a curved arch shape, whereby the rigidity of the arm can be increased and the weight of the device member can be reduced. At the same time, since the microscope component parts are independently fixed to the arm, the entire structural system itself is less likely to be a vibration source, and external vibration is also less likely to propagate.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of a microscope according to the present invention.

FIG. 2 is a plan view of the microscope shown in FIG.

FIG. 3 is a schematic front view showing an example of the shape of an arm of a microscope according to the present invention.

FIG. 4 is a side view showing an example of a conventional microscope.

5 is a plan view of the microscope shown in FIG.

[Explanation of symbols]

 1 Base 2 Objective Lens 3 Reflection Illuminator 4 Stage 5, 6 Guide Rail 7 Arm 10 Microscope Optical System 12 Eyepiece 13 Observation Lens Tube 14 Extension Relay Lens Tube 15 Focusing Elevating Mechanism 20 Deflection Optical System 20A First Deflection Angle Prism A1 Objective lens Vertical optical axis A2 Relay optical system optical axis A3 Lens tube optical axis

Claims (2)

[Claims] 1. A base, a stage fixed on the base and movable along a predetermined guide member, a gate-shaped arm fixed to the base so as to straddle the stage, and the arm. An objective lens that is supported by a focusing elevating mechanism that is fixedly attached to the stage so as to be capable of moving up and down, and focuses on a sample placed on the stage; A microscope provided with a relay optical system that extends an optical path deflected by the deflection optical system and guides the optical path to an observation lens barrel optical system, wherein the portal arm has a curved arch shape. 2. The gate-shaped arm has an arcuate arch shape, the focusing elevating mechanism is suspended at a substantially vertex position of the arc, and an extension relay barrel for accommodating the relay optical system is provided in a longitudinal direction. The microscope according to claim 1, wherein the observation lens barrel, which is integrally attached and accommodates the observation lens barrel optical system, is directly attached to the arm body.