JPH06194579A - Stage that can be finley adjusted along straight line - Google Patents

Abstract

PURPOSE: To enable adjustment without play and friction but with resolution as high as possible over a comparatively short adjusting distance and to satisfactorily prevent the horizontal movement of a stage plate even with a thermal drift by improving a stage for especially an optical device or a microscope with high resolution. CONSTITUTION: The stage is provided with a piezoelectric parallel movement device 5 directly driving the center of the stage plate 2, and a linear guide mechanism consisting of at least two elastic members 6 and 7 for guiding the stage plate 2. The elastic members 6 and 7 are coaxially arranged to the movement device 5, which penetrates a chamfer or a hole provided at the center of the elastic member 6 and 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear fine-adjustable stage, especially for optical instruments or microscopes.

[0002]

BACKGROUND OF THE INVENTION In microscopic adjustment to a linear fine-adjustable stage for optical instruments or microscopes, the sample stage is usually adjusted for aiming, either manually or electrically via a high reduction ratio transmission, and It is linearly guided along the frame of the microscope by a sliding guide mechanism or a ball guide mechanism. However, this known means can only fulfill its requirements if the weight is placed on a relatively large adjustment range, rather than on the highest possible distance resolution and as little play and friction as possible.

However, there are quite a lot of use cases in which importance is attached to the highest possible distance resolution and the elimination of play and friction as much as possible. In such applications, so-called "piezoelectric translational movement devices" are nominated, and these known piezoelectric translational movement devices are partly equipped with a distance signal generator and a guide mechanism for the part to be adjusted. Attached and provided by various manufacturers. Such an adjusting member is for example disclosed in German Patent Application DE 363296.
No. 4 specification. In this known technique, a spring rod is used to guide the driven member, one side of the guided part being connected via said spring rod to a holding body, i.e. the stationary part of the adjusting member.

However, the reason why such a one-sided guide is not preferable is that it promotes a temperature drift in the radial direction, that is, the guided portion is moved in the guide direction due to the thermal length variation of the guide member. Because it is displaced in the vertical direction. Further, such a guide mechanism integrally incorporated in the adjusting member generally does not meet the user's requirements in terms of size.

A plate supported by three piezoelectric translational devices is known from US Pat. No. 4,785,177, which plate is not only finely tuned in height, but also the three piezoelectric plates. It is horizontally shifted and rotated at a suitable control frequency which loads the translational drive. Therefore, the plate is neither linearly guided nor prevented from lateral displacement.

It is known from German Patent DE 100 614 14 A1 to linearly guide a microscope objective through a diaphragm spring in a microhardness tester. However, the diaphragm spring in this case has a large number of circumferential slits in order to obtain as large a spring travel as possible, and a bellows filled with air is used for driving. Hereby it is not possible to realize a finely divided adjusted feed movement.

[0007]

SUMMARY OF THE INVENTION The object of the invention is to improve high-resolution stages, in particular for optical instruments or microscopes, so that they can be adjusted as play-free and friction-free with the highest possible resolution over relatively small adjustment distances. In addition, the lateral movement of the stage plate is favorably prevented even by thermal drift.

Such a stage is, for example, a so-called z image of an object to be inspected, which is an image of the object to be inspected from different planes of the object.
It is required in the case of a confocal microscope having a high resolution so as to obtain a directional resolution.

[0009]

Means for Solving the Problems The constituent means of the present invention for solving the above-mentioned problems include a piezoelectric translation device for directly driving the center of a stage plate and at least two elastic members for guiding the stage plate. A linear guide mechanism made of a member, wherein the elastic member is coaxially arranged with respect to the piezoelectric translation device, and the piezoelectric translation device is provided with a cutting hole formed in the center of the elastic member. It is at a point that penetrates the notch or hole.

[0010]

Since the piezoelectric translational movement device and the linear guide mechanism are coaxially arranged, a compact structure can be obtained which does not cause temperature drift in the radial direction and saves a required space. The structure is also extremely rigid in the guide direction. This is because the piezoelectric translation device drives the center of the stage plate directly. Not only that, a very symmetrical simple structure of the stage is obtained. As the elastic member, it is possible to use, for example, a ring-shaped diaphragm spring or a plurality of spring joint groups arranged in parallel with each other and composed of spring joints which are sequentially connected in succession. With both guide mechanisms, play is eliminated and good parallelism of the guide movement is obtained.

[0011]

Embodiments of the present invention will now be described in detail with reference to the drawings.

The stage shown in FIG. 1 is a stationary cylindrical member 3
The cylindrical member is fixed to the stationary stage support 1 or to an instrument using the stage in a manner not shown in detail. A piezo-electric translation device 5 is fixed to the center of the bottom of the cylindrical body by means of a screw 9, and the adjustable head part 8 of the piezo-electric translation device is mounted on the stage plate 2 located above it. Work towards the bottom. In this case, the piezoelectric translational movement device 5 is a Physic
This is a product sold by Instrumente GmbH (Waldbronn, Germany) under the trade name LVPC Translator P-841.40.

The piezo-electric translator 5 incorporating a position sensor adjusts the stage plate 2 in the direction of the double arrow z with a very high bending stiffness without hysteresis via a connected electronic control system. You can

A cylindrical member 4 is screwed to the lower surface of the stage plate 2, and the cylindrical member 4 has two ring shapes made of sintered bronze and arranged at a distance of about 8 cm from each other in the z direction. It is connected to the stationary cylindrical member 3 via diaphragm springs 6 and 7. One of the two diaphragm springs, namely the diaphragm spring 6, is shown in plan view in FIG. Both diaphragm springs 6 and 7 guide the stage plate 2 without play over an adjusting distance from a few hundredths of a millimeter to a tenth of a millimeter. Within the range adapted to the adjustment distance of the piezoelectric translation device 5, elastic deformation of the diaphragm spring merely occurs.

The structure of the second embodiment shown in FIG. 2 is very similar in principle. In FIG. 2, the stationary stage support is designated by 11. A support ring 21 is supported on the stage support, and an outer cylindrical member 13 which is stationary with respect to the fine adjustment movement of the stage is supported on the upper surface of the support ring via a threaded ring 25. .
The threaded ring 25 causes the outer cylindrical member 13 to
A coarse adjustment movement can be performed in the direction. The support ring 2
Groove 24 in the outer cylindrical member 13 provided in the outer cylindrical member 13.
The pin 23 engaged with is for linearly guiding the stage during the coarse adjustment movement, and also the outer cylindrical member 1
3 can be fixed in position (tightened) to the stage support 11 by means of a knurled screw 22. On the outer cylindrical member 13, a cylindrical bottom member 10 is also provided.
It is screwed via 13. Between the ring 113 and the cylindrical bottom member 10 and between the ring 123 and the outer cylindrical member 13, one ring-shaped diaphragm spring 16 or 17 is fastened at its outer edge. The inner edge of the diaphragm spring 17 has two rings 114 and 12
It is tightened between 4 and. Both rings 114 and 124
Are simultaneously screwed to the lower surface of the inner cylindrical member 14.

The inner edge of the other diaphragm spring 16 is finally tightened between the upper surface of the inner cylindrical member 14 and the ring collar provided in the central area of the lower surface of the stage plate 12. In this way, also in this embodiment, both diaphragm springs 1
Reference numerals 6 and 17 form a guide mechanism for the stage plate 12. At the center of the cylindrical bottom member 10, a piezoelectric translational motion device 15 is incorporated via a screw 19 and an adjusting disk 28. The movable adjusting member 18 of the piezoelectric translation device is
Adjustment screw 20 screwed into the center of the stage plate 12
Work towards the underside of.

The piezoelectric translation device 15 in this case is of the same type already described in connection with FIG. The control cable 26 and the signal cable of the position sensor, which are integrated in the piezoelectric translation device, are led out through lateral openings bored in both the inner and outer cylindrical members 13 and 14.

The diaphragm springs 16 and 17 are made of a bronze thin plate having a spring rigidity and a thickness of 0.05 mm.
The inner hole and outer diameter of both diaphragm springs are concentrically formed as a fitting means for coaxially aligning the inner and outer cylindrical members 13 and 14 during assembly.

A point to be noted when assembling the two diaphragm springs 16 and 17 is to position the inner and outer tightening portions at exactly the same height each time in order to avoid distortion of the diaphragm spring when assembled. Is. Therefore, three support screws 30 are provided as assembly aids, of which only one is shown in FIG. The support screw 30 is removed after assembly.

In the embodiment shown in FIGS. 4 to 6, the piezoelectric type translational motion devices 35 supported by the stationary stage support member 31 and driving the center of the stage plate 32 are sequentially connected one after another. It is surrounded by two spring joint groups 36, 37 which are arranged parallel to each other and which consist of a plurality of spring joints. The first group of spring joints 37 consists of four ring-shaped plates with a central hole, which ring-shaped plates alternate alternately on the right and left sides of the material webs 33a, 33.
Bound by b, 33c, the web of material acts as a hinge point. All tilting axes of this first spring joint group 37 are oriented parallel to the direction indicated by the symbol y in FIG.

A second spring joint group 36 is arranged inside a first spring joint group 37 composed of this ring-shaped plate, and the second spring joint group 36 also sequentially moves the ring-shaped plates one after another. It consists of multiple spring joints that connect. Material webs 34a, 34b, 34c connect the four ring-shaped plates of the second spring joint group to one another, as can be seen from the sectional view of FIG. All the tilt axis lines of the second spring joint group 36 are indicated by the symbol x in FIG.
It is oriented parallel to the direction indicated by. Both ring-shaped spring joint groups 16 and 17 are connected to each other via a plate 38 on their lower surface and, at the same time, are screwed to the stage plate 32 on their upper surface. By pivoting the directions of the tilt axes 90 ° relative to each other and arranging both spring joint groups in parallel, a straight guide mechanism with a tilt-proof and simple manufacture is formed. This is because the linear guide mechanism consists only of turning parts. The linear guide mechanism is also free of play and friction, dust-proof, and stable against radial temperature drift.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a stage according to a first embodiment shown in a cross section in a plane parallel to a guide device.

FIG. 2 is an enlarged sectional view of a stage according to a second embodiment.

FIG. 3 is a plan view of the diaphragm spring of the first embodiment shown in FIG.

FIG. 4 is a cross-sectional view of a different embodiment of the present invention shown in section in a first plane parallel to the guide device.

5 is a sectional view taken along a plane perpendicular to the guide device, and is a sectional view taken along line VV of FIG.

6 is a cross-sectional view of the embodiment of FIG. 4 rotated 90 ° relative to the view of FIG. 4 and shown in cross-section in another plane parallel to the guide device.

[Explanation of symbols]

1 stationary stage support, 2 stage plate, 3 stationary cylindrical member, 4 cylindrical member, 5
Piezoelectric translation device, 6,7 diaphragm spring, 8 adjustable head part, 9 screw,
10 cylindrical bottom member, 11 stationary stage support, 12 stage plate, 13 outer cylindrical member, 14 inner cylindrical member, 15 piezoelectric translation device, 16, 17 ring-shaped diaphragm spring, 18 movable adjusting member, 19 screw , 2
0 adjusting screw, 21 support ring, 22 knurled screw, 23 pin, 24 groove, 25
Threaded ring, 26 Control cable, 27
Signal cable, 28 adjusting disc, 30 support screw, 31 stationary stage support member, 32
Stage plate, 33a, 33b, 33c; 34
a, 34b, 34c material web, 35 piezoelectric translation device, 36, 37 first and second group spring joints, 38 plates, 113, 114 rings,
123,124 ring

Claims (8)

[Claims] 1. A stage plate (2; 12; in a stage capable of fine adjustment of linear movement for an optical instrument or a microscope).
32) Piezoelectric translation device (5;
15; 35) and the stage plate (2; 12; 3)
2) and a linear guide mechanism composed of at least two elastic members (6, 7; 16, 17; 36, 37) for guiding the elastic member (6, 7; 16, 17;
36, 37) is the piezoelectric translation device (5; 15; 3)
5) is arranged coaxially with respect to 5), and the piezoelectric type translational movement device penetrates a notch or a hole formed in the center of the elastic member, and fine adjustment of linear movement is possible. stage. 2. A plurality of elastic members are ring-shaped diaphragm springs (6, 7; 16, 17), and the diaphragm springs are provided on an adjustable stage plate (2; 12) and are cylindrical members (4; 14. The stage according to claim 1, which is fixed to the fixed stage support (1; 11) with a cylindrical member (3; 13) at a distance from each other in the adjustment direction. 3. A plurality of spring joints (33a, 33b, 33c; 34a, in which both elastic members are connected one after another in sequence).
34b, 34c) each having a spring joint group (36, 37), said spring joints having the same axial direction (x,
y) is tiltable about the tilt axis, both spring joint groups (36, 37) are juxtaposed to each other, and the axial direction (x, y) of the tilt axis of both spring joint groups.
Are arranged at a mutual angle different from 0 °. 4. The stage according to claim 3, wherein the angle formed by the tilting axes of both spring joint groups (36, 37) is 90 °. 5. Spring joints (33a, 3) in which each spring joint group (36, 37) is connected in at least two phases before and after.
3b, 33c; 34a, 34b, 34c). 6. A piezoelectric translation device (5; 15; 35).
The stage of claim 1 having a position sensor incorporated within the piezoelectric translation device. 7. The stage additionally comprises a coarse adjustment mechanism (25).
The stage according to claim 1, further comprising: a linear guide mechanism 23 for rough adjustment. 8. Use as a sample stage in a high resolution microscope such as a confocal microscope.
The stage according to any one of 1 to 6 above.