JP2938954B2 - Focusing device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a focusing device for focusing on a microscope, a measuring instrument, and the like by vertically moving a mounting table on which a sample is mounted.

[Conventional technology]

In recent years, specimens on which various inspections are performed by optical devices such as microscopes and measuring instruments tend to be large and heavy, and because precise measurements are required, these optical devices require a sufficient mounting table. It is necessary that the focusing mechanism has high rigidity and high precision.

However, in the conventional focusing device of a microscope, for example, as shown in FIG. 5, the mounting table 1 is cantilevered by the microscope main body 3 via the vertical drive mechanism 2, so that a heavy sample is mounted or mounted. When the stage 1 is moved up and down, the stage 1 does not have sufficient rigidity such that the stage 1 is bent or vibrated and the objective optical system 4 is out of focus. 5 is an illumination light source,
Reference numeral 6 denotes a mirror that reflects the illumination light beam at a right angle and guides the illumination light beam to a sample (not shown) on the stage 1 via the condenser lens 7.

To improve this, for example, West German Patent No. 36
No. 42798A1 discloses a device in which a linear ball guide 9 is fitted to at least three columns 8 and the stage 1 is fixed thereon, as shown in FIG. A vertical drive mechanism 10 for the stage 1 comprising a rack and pinion mechanism is provided near the optical axis to provide the stage 1 with rigidity and vertical movement stability.

As another example, in an apparatus proposed by the present applicant in Japanese Patent Application No. 1-192536, as shown in FIGS. 7 and 8, a square tube type fixed to a microscope body (not shown) is used. Outer frame 12
Inside, a hollow structure base 13 on which the mounting base 1 is fixed.
Are arranged so as to be slidable in the up and down direction, and the table 13 is guided by four sets of up and down roller guides 14 provided at four corners between the outer frame 12 and the base 13 so as to linearly move. It has become. In order to assure a precise linear movement of the base 13, steps 13a and 12a are formed on the square of the base 13 where the roller guide 14 is mounted and on the corresponding inner surface of the outer frame 12, respectively.

A pinion 15a that meshes with a rack 16 provided on one side of the base 13 is fixed to a central portion of the drive shaft 15 rotatably mounted on the outer frame 12, and these constitute drive means. I have.

Note that a mirror 6 having a 45 ° angle for bending the illumination light incident from the hole 12b of the outer frame 12 upward at a right angle is supported by a column 17 in the hollow structure base 13, and further above the mirror. On the illumination light path, a condenser lens 19 fixed to the top of the support cylinder 18 and a diaphragm (not shown) in the lens 10 whose light amount is adjusted by a diaphragm adjustment lever 20 are arranged.

With such a configuration, it is possible to obtain a focusing device capable of achieving high-precision smooth vertical movement of the stage 1 and high rigidity.

[Problems to be solved by the invention]

However, among the above-mentioned prior arts, in the apparatus shown in FIG. 6, the structure itself in which the stage 1 constituted by one plate is supported by three separate linear ball guides 9 has a problem in strength. In addition, it is difficult to adjust the parallelism of the three columns 8 or the linear ball guide 9 and the columns 8
Due to the short length of the fitting contact portion, there is a problem that a fall or shortage of a stroke is likely to occur, and the entire device becomes large.

The apparatus shown in FIGS. 7 and 8 can considerably solve the above-mentioned problems. However, in order to realize the smooth vertical movement of the base 13 by three or more sets of the roller guides 14, the components shown in FIGS. It is necessary to keep the dimensional accuracy of the hologram high, which is very difficult. That is, for example, when four sets of the roller guides 14 are used as the guide members of the base 13 as described above, the direction of the linear motion of the base 13 is determined by the two sets of the roller guides. become. Accordingly, while maintaining the accuracy of the linear motion of the platform 13 determined by the two roller guides 14 out of the four, the direction perpendicular to the direction of the linear motion applied to the stage itself by the heavy sample or the stage 1 is maintained. Although it is better to use three or more sets of roller guides in order to maintain the rigidity against the force of (1), when four sets of roller guides are used (for example), each accuracy for the following points is regulated. Unless it is within the error, the stage 1 cannot be moved with high accuracy and smoothness. That is, regarding the respective surfaces of the outer frame 12 and the steps 12a, 13a of the base 13 shown in FIG.
Between B, C, D, 12a-E, F, G, H, between surfaces 13a-I, J, K, L, and for perpendicularity, surfaces 13a-A and I, B, J, C And K, D
And L, 12a-E and M, and dimensional differences are between a and c, b and d.

However, in general, in order to maintain the dimensional accuracy of such many surfaces at the same time, it is necessary to make the mutual configuration between the outer frame 12 and the movable base 13 precise. It is very difficult to realize).

In view of such circumstances, the present invention has a relatively simple configuration, and has sufficient rigidity even for a large and heavy sample or a stage, and can perform a linear motion with high accuracy. It is another object of the present invention to provide a linear guide mechanism for a focusing device.

[Means for solving the problem]

A focusing device according to the present invention includes a movable table having a hollow structure for vertically moving a mounting table around an optical axis of an optical apparatus, and a guide fixed to a main body of the optical apparatus and disposed outside the movable table. A fixed member, driving means for vertically driving the movable table, and at least three sets of guide members disposed between the movable table and the guide fixing member for guiding the linear movement of the movable table. The guide member is disposed separately on the drive unit side and the opposite side with respect to the optical axis, and has at least one guide member with an adjusting mechanism for adjusting the linear movement of the movable base. It is characterized by having.

(Operation)

According to the present invention, the movable table supporting the stage is divided and disposed so as to face each other with the optical axis of the optical device therebetween.
High rigidity is ensured by being guided up and down by more than one set of guide members, and an adjusting mechanism for adjusting the linear movement is provided, so that assembly is easy, and the linear movement of the movable base can be performed with high precision. .

〔Example〕

Hereinafter, a preferred embodiment of the present invention will be described with reference to FIGS. 1 to 3, but the same parts as those in the above-described prior art will be denoted by the same reference numerals and description thereof will be omitted.

In the figure, reference numeral 22 denotes a movable base having a shape and a configuration similar to that of the base 13 described above, for example, a rectangular cylindrical hollow body, and a rack 23 that meshes with the pinion 15a of the drive shaft 15 is provided on one side of the outer periphery. ing. On the four corners, two movable cross roller guides 24 and two auxiliary cross roller guides 25 each movable-side track.
Steps 22a each composed of two orthogonal surfaces for attaching 24a and 25a are formed, and each step 2
It is assumed that the one surface 22a-A, B, C, and D of 2a is guaranteed to be parallel to each other, and the parallelism is suppressed to, for example, 0.01 or less. Reference numeral 26 denotes a hole (see FIG. 2) formed on one side surface of the movable base 22 for introducing an illumination light beam, 27 denotes an inner wall for fixing the condenser lens 19 in the movable base 22, and 28 denotes a central part of the inner wall. It is an internal hole that is provided and allows the light beam bent by the mirror 6 to pass in the direction of the condenser lens 19 and the sample.

Reference numeral 30 denotes an outer frame main body which is disposed so as to surround, for example, three outer peripheral surfaces of the movable base 22 and has a substantially U-shaped cross section, and has two inner corner portions each having a fixed side track base 24b of the main cross roller guide 24.
Are formed in parallel plane portions 30a-A, B, which are parallel to each other and have guaranteed dimensional accuracy for tightly fixing them. The parallel plane portions 30a-A, B are the respective surfaces 22a-A, B, C, D of the step portion 22a of the movable base 22.
Are arranged in parallel with In addition, ideally, the plane orthogonal to the plane parts 30a-A, B with which the fixed-side way 24b contacts,
Preferably, it is parallel to a plane orthogonal to the planes 22a-A, B, C, D of the step 22a. At the time of assembling and the like, the two main cross roller guides 24 are configured such that the movable-side track 24a and the fixed-side track 24b are parallel to the surfaces 22a-A, 22a-B of the step 22a and the parallel plane portions 30a-A, respectively.
By being fixed closely to B, the direction of the linear motion of the movable base 22 with respect to the outer frame main body 30 is determined. Reference numeral 31 denotes a bottom plate that supports the outer frame main body 30 and the column 17, and 32 denotes a hole formed in the outer frame main body 30 that guides the illumination light beam to the mirror 6 through the hole 26 of the movable base 22.

34 is attached to the opening of the outer frame body 30 and
Is a fixed frame that surrounds the movable base 22 and fixes the two sub-cross roller guides 25 together with the movable base 22. The fixed rail way 25b of the roller guide 25 is tightly fixed to the inner wall of the fixed frame, and the dimensional accuracy is guaranteed. Parallel plane portions 34a-C, D are provided,
The parallel plane portions 34a-C and D are formed parallel to each other. An adjusting mechanism 35 is provided at the two connection fixing portions of the outer frame main body 30 and the fixing frame 34 so as to adjust the mounting position of the fixing frame 34 in the direction of the arrow in FIG.

The adjusting mechanism 35 will be described with reference to FIG. 3. Reference numeral 37 denotes a bolt for fixing the fixed-side track 25b of the auxiliary cross roller guide 25, and reference numeral 38 denotes a bolt for fixing the fixed frame 34 to the outer frame body 30. Numeral 39 denotes an adjusting bolt for adjusting the mounting position of the fixed frame 34 with respect to the outer frame main body 30 by contacting the end surface of the movable base 22 with the end surface of the outer frame main body 30. The position of the auxiliary cross roller guide 25 can be finely adjusted so as to follow the direction of the linear motion. Reference numeral 40 denotes a preload adjusting bolt for adjusting the preload, that is, the sliding friction, of the sub-cross roller guide 25, the leading end surface of which is in contact with the fixed-side track 25b.

Since the present embodiment is configured as described above, at the time of assembling the focusing device or the like, the four movable steps 22a of the movable base 22 are respectively provided on the respective surfaces 22a-A, B, C, and D of the movable-side track bases. 24a, 24a, 25a, 25a are mounted, and fixed side raceways 24b, 24b mounted on the parallel plane portions 30a-A, B of the outer frame body 30 are mounted on two movable side raceways 24a, 24a. The movable table 22 is disposed on the outer frame body 30 so as to be fitted via a cross roller. The two main cross roller guides 24, 24 formed thereby determine a highly accurate linear motion of the movable base 22.

Further, the remaining two movable track bases 25a and 25a attached to the movable base 22 are fixed to the fixed track 2 via cross rollers.
The fixed frame 34 is attached to the outer frame body 30 so that 5b and 25b are fitted. In this case, it is necessary to adjust the position of the fixed frame 34 by the adjusting mechanism 35 so that the two sub-cross roller guides 25, 25 to be formed do not impair the already determined linear motion of the movable base 22.

This will be described mainly with reference to FIG. 3. First, the fixed-side way 25b is fixed to the parallel plane portions 34a-C of the fixed frame 34 by bolts 37.
(And D), and fix the fixing frame 34 to the mounting bolt 38
Is temporarily fixed to the outer frame body 30. Then, while tightening the preload adjusting bolt 40 and pressing the fixed-side track 25b to the movable-side track 25a via the cross roller, the fixed-side track 25b is fixed by the adjusting bolt 39 so as to follow the linear motion of the movable table 22 which has already been determined. The position adjustment of the side track 25b, that is, the fixed frame 34 is performed. After the adjustment, tighten the mounting bolts 38 to
Is securely fixed to the outer frame body 30, and the preload adjusting bolt 40
After the adjustment of the guide preload is completed with the bolts 37, the fixed-side way 25b is securely fixed by the bolt 37 to the parallel plane portion 34a- of the fixed plate 34.
Fix to C (and D).

By performing such an adjustment operation, a linear guide mechanism for the movable table 22 is formed along the direction of linear motion determined by the two main cross roller guides 24, 24. On the other hand, high rigidity can be maintained. Therefore, when the drive shaft 15 is rotated, the movable table 22 moves up and down with high precision via the pinion 15a and the rack 23, and the stage 1 moves up and down to perform focus adjustment.

As described above, according to the present embodiment, the outer frame main body 30 and the fixed frame 34 require fewer surfaces as compared with the outer frame according to the prior art, so that manufacturing is easy, and the fixed frame 34 By performing the position adjustment, the linear motion of the movable base 22 can be controlled with high accuracy, and the high rigidity of the linear guide mechanism can be maintained.

Next, FIG. 4 shows a modification of the present invention, in which a sub-cross roller guide held by a fixed frame 34 and a movable base 22 is shown.
25 is replaced by a flat roller guide 41.

Note that the guide members are not limited to the cross roller guides 24 and 25 and the flat roller guide 41, and any other suitable members such as ball guides for all four sets of guide members may be used as another example.

Also, the guide members are not necessarily required to be four sets, and an appropriate number of sets may be adopted, for example, three sets may be employed. In this case, one set of guide members may be disposed at the center of the fixed frame 34.

Also, the fixed frame 34 does not necessarily need to be constituted by one sheet,
It may be constituted by a plurality of sheets.

〔The invention's effect〕

As described above, according to the focusing apparatus according to the present invention, since the adjusting mechanism for adjusting the rectilinear movement of the movable base is provided, it is easy to adjust the position of each member at the time of assembly and the like, and moreover, The linear motion can be controlled with high precision, and the high rigidity of the linear guide mechanism can be maintained.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 to 3 show an embodiment of a focusing device according to the present invention, wherein FIG. 1 is a horizontal sectional view, FIG. 2 is a vertical sectional view, and FIG. FIG. 4 is a horizontal sectional view of a main part of an adjusting mechanism, FIG. 4 is a horizontal cross-sectional view showing a modification of the embodiment, FIG. 5 is a schematic view of a conventional example, FIG. 7 is a horizontal sectional view of the prior art, FIG. 8 is a longitudinal sectional view of the prior art of FIG. 7, and FIG. 9 is a horizontal sectional view showing the relationship between the movable base and the outer frame in the prior art of FIG. It is. 15 ... Drive shaft, 15a ... Pinion, 22 ... Movable table, 23 ...
... Rack, 24 ... Main cross roller guide, 25 ... Sub cross roller guide, 30 ... Outer frame body, 34 ... Fixed frame, 35 ...
... adjustment mechanism.

Claims (1)

(57) [Claims] A movable table having a hollow structure for vertically moving a mounting table about an optical axis of the optical apparatus; a guide fixing member fixed to a main body of the optical apparatus and disposed outside the movable table. Driving means for vertically driving the movable table; and at least three sets of guide members disposed between the movable table and the guide fixing member for guiding the linear movement of the movable table, The guide member is disposed separately on the drive unit side and the opposite side with respect to the optical axis, and has an adjusting mechanism for adjusting the linear movement of the movable table on at least one side of the guide member. A focusing device, comprising: