JP3217396B2 - Microscopic coarse / fine movement mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coarse / fine movement mechanism for focusing a microscope.

[0002]

2. Description of the Related Art The structure of a conventional microscope will be described by taking an inverted microscope as an example. In FIG.
Is a microscope main body, reference numeral 2 is an illumination device, reference numeral 3 is a condenser lens, reference numeral 4 is a stage fixed to the microscope main body, reference numeral 5 is an objective lens, reference numeral 6 supports the objective lens 5, and is mounted on the microscope main body 1. The revolver attached to the reduction gear 6b, the rack mechanism 6c, and the guide member 6a and movable along the optical axis Z, reference numeral 7 is an operation handle for focusing, and reference numeral 8 is an eyepiece tube for observing a sample. Each is shown.

As a coarse / fine movement mechanism used in such an inverted microscope, for example, a mechanism disclosed in Japanese Patent Publication No. 52-46888 is known. This coarse / fine movement mechanism is configured to coarsely / finely move a microscope stage or a revolver in the optical axis direction using a gear train and a rack and pinion.

However, the coarse / fine movement mechanism disclosed in Japanese Patent Publication No. 52-43688 requires a gear mechanism for speed reduction between the coarse movement handle and the fine movement handle. There is a disadvantage that the cost is high. In addition, the accuracy of fine focus adjustment is limited to 1-2 μm in the reproducibility of the vertical movement position of the objective lens with respect to the rotation of the fine movement handle due to the transmission loss due to the gear train and the bending of the mechanism. Further, as shown in FIG. 4, due to the gear pressure angle α of the rack and pinion mechanism, when the objective lens moves up and down in the optical axis direction, a force (component force) acting in a direction perpendicular to the moving direction is generated, This causes the guide member to bend. This causes the objective lens 5 to be displaced in the direction of the arrow as shown in FIG. 3, which causes a so-called image eccentricity in the field of view.

In recent years, a computer image processing technique has been combined as a microscope observation technique, and a plurality of observation images are captured in small steps in the optical axis direction of the objective lens, and then these images are used to reconstruct a three-dimensional image. Optical sectioning observation is being performed. Alternatively, in a laser scanning microscope that obtains a fluorescent image by performing two-dimensional scanning using laser light as excitation light, the objective lens is sent in small steps in the optical axis direction to obtain a plurality of sectioning images, and then has a certain thickness. Attempts have been made to obtain an image in which the entire specimen is focused, or to obtain a three-dimensional image.

In such an application, a stepping motor is connected to the fine movement handle, and the objective lens is fed in the direction of the optical axis in synchronization with the timing at which the two-dimensional scan image is taken into the image memory, thereby performing sectioning. Problems in taking the two-dimensional scan image into the image memory include the position reproducibility (position resolution) and the feed speed of the objective lens in the optical axis direction. This is because the interval dimension for sectioning the specimen is 1 μ or less, and the reproducibility of the position in the optical axis direction is desired to be less than that. This is because the number of samples that move with a heartbeat movement is increasing, and it is desired to capture images at a higher speed.

However, in the above-described fine focusing mechanism using a gear train, the reproducibility of the position is limited to 1 to 2 μm. Also, as described above, if the objective lens is decentered in the direction perpendicular to the optical axis, when performing image processing by combining the sectioning images, the apparent resolution is reduced, and the constructed image is distorted and reproduced. .

As another coarse / fine movement mechanism, a mechanism in which a piezo element is combined with a fine movement feed mechanism to feed the objective lens in small steps in the optical axis direction has been put to practical use. Although the reproducibility of the position is as high as 0.1 μ or less, a high accuracy can be obtained. However, the feed speed of the objective lens is reduced by 100% because the mechanical system damping accompanying the operation of the piezo element occurs.
It takes about msec. In consideration of video recording and TV analysis, it is desired that the feed speed be 30 msec or less. Therefore, a fine movement feed mechanism using a piezo element is not sufficient.

SUMMARY OF THE INVENTION The present invention has been made to solve these problems. In a feed mechanism for moving an objective lens or a stage by a fine movement handle in the optical axis direction, the repeatability of the feed position is improved and the feed speed is increased. It is an object of the present invention to provide an inexpensive and high-performance coarse / fine movement mechanism capable of capturing a sectioning image with high accuracy and high speed by achieving speeding up.

[0010]

According to the first aspect of the present invention,
A coarse / fine movement mechanism of a microscope for performing focusing by coarsely moving / finely moving an objective lens or a stage in an optical axis direction of the objective lens, wherein a fine movement table moving in the optical axis direction integrally with the objective lens or the stage; A coarse moving table movable in the optical axis direction and arranged in series with the fine moving table; and a fixed guide for coaxially supporting both the fine moving table and the coarse moving table so as to be movable in the optical axis direction. A cylinder of the fluid drive device provided between the fine moving table and the coarse moving table and capable of extending and contracting in the optical axis direction, and a rack provided on the coarse moving table for coarsely driving the coarse moving table A pinion mechanism, wherein the coarse and fine moving tables are coarsely moved in the optical axis direction integrally by the rack and pinion mechanism, and the fine moving table is finely moved with respect to the coarse moving table by expansion and contraction of the cylinder. Features It is. According to a second aspect of the present invention, in the first aspect of the present invention, a spring for applying a force for compressing the cylinder is provided between the coarse moving table and the fine moving table. According to a third aspect of the present invention, in the first aspect of the present invention, there is provided a fine movement operation section for driving the cylinder, and a coarse movement handle for driving the rack and pinion mechanism. It is characterized by being arranged coaxially. According to a fourth aspect of the present invention, there is provided a coarse / fine movement mechanism of a microscope for performing focus adjustment by coarsely / finely moving an objective lens or a stage in the optical axis direction of the objective lens, wherein the optical axis direction is integrated with the objective lens or the stage. And a coarse moving table movable in the optical axis direction and arranged in series with the fine moving table, and both the fine moving table and the coarse moving table can be moved in the optical axis direction. A fixed guide that is coaxially supported, a fine movement drive device that is provided between the fine movement table and the coarse movement table, and generates a driving force only in the optical axis direction, and for coarsely driving the coarse movement table. A rack and pinion mechanism provided on the coarse motion table, wherein the coarse and fine motion tables are coarsely moved integrally in the optical axis direction by the rack and pinion mechanism, and the coarse motion table is moved by the fine motion drive device. Against the fine table It is characterized in that fine movement. According to a fifth aspect of the present invention, there is provided a coarse / fine movement mechanism of a microscope for performing focus adjustment by coarsely / finely moving an objective lens or a stage in the optical axis direction of the objective lens, wherein the optical axis direction is integrated with the objective lens or the stage. A fine moving table, and a cylinder of a fluid drive device for finely moving the fine moving table in the optical axis direction, and a fine moving operation section for driving the cylinder is coaxial with a coarse moving handle for performing a coarse moving operation. It is characterized by being arranged.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to FIGS.

Reference numeral 10 denotes a revolver to which a plurality of objective lenses having different magnifications can be attached. In the figure, only one objective lens 11 is shown. This objective lens 11
Are arranged so as to observe the sample placed on the stage 13 indicated by the broken line from below. The observer observes the revolver 10
Is rotated to convert the objective lens attached thereto into the optical axis Z and observe the sample.

The revolver 10 is fixed to a revolver stand 14. The revolver table 14 has a pair of guide grooves 14a on both side surfaces. A known roller is rolled in the guide grooves 14a and the guide grooves 17a provided in the fixed guide 17, and the revolver table 14 is moved along the optical axis Z. It constitutes a guide mechanism for fine movement in the direction.

Reference numeral 16 denotes a coarse movement guide, on both sides of which a guide groove 16a is formed. The guide groove 16 a is formed so as to be coaxial with the guide groove 14 a of the revolver table 14,
A roller guide (not shown) guide mechanism that can move in the optical axis Z direction is configured in combination with a. Further, a rack 18 is fixed to the coarse movement guide 16.

A cylinder 20 of the fluid drive device is fixed to the upper end of the coarse movement guide 16, and its piston 23 is in contact with the lower end surface of the revolver table 14. As a result, the revolver 1
4 can be moved up and down. Further, the piston 23 of the cylinder 20 abuts firmly on the revolver table 14, and a coil spring 25 for applying a constant pressing force so as to prevent a gap and play from being generated between the coarse movement guide 16 and the revolver table 14. It is provided.

The coarse focus handles 30, 30 are formed integrally with a pinion shaft 31. Pinion shaft 31
The rack 18 is arranged at a position where the pinion 31a formed in the rack 18 and the rack 18 appropriately mesh with each other. The fine focus handles 33, 33 are arranged coaxially with the coarse focus hands 30, 30, and the fine focus handles 33,
33 is a fine movement shaft 3 penetrating through the center hollow of the pinion shaft 31
5 (see FIG. 2). The fluid drive device constituting the fine focus mechanism will be described with reference to FIG. The cylinder 20 is driven by the operation side unit 20a.

The cylinder 20 comprises a front cylinder 40 and a rear cylinder 41. A hat-shaped rolling diaphragm 42 in which cloth is coated with a synthetic rubber material is tightly fitted between the two cylinders, and the inside of the cylinder is partitioned into an empty chamber a and an oil chamber b. The end of the rolling diaphragm 42 is fixed to the rear end of the piston 23. Reference numeral 44 denotes an oil chamber b
The hose 45 is attached here, and the cylinder 20 side and the operation side unit 20a are fluidly connected. For example, a fluororesin is selected for the hose 45 so as to withstand temperature changes and oil pressure. The rear cylinder 41 of the cylinder 20 is embedded in the coarse movement guide 16 and is fixed by a fixing screw 47.

Similarly to the cylinder 20, the operation side unit 20a has a front cylinder 51, a rear cylinder 52, a rolling diaphragm 5
3 and so on. Reference numeral 54 denotes a piston, one end of which is fixed to the rolling diaphragm 53. The inside of the front cylinder 51 and the rear cylinder 52 is partitioned by a rolling diaphragm 53 into an empty chamber a1 and an oil chamber b1. The other end of the piston 54 is in contact with a screw shaft 56 via a ball 55. The screw shaft 56 and the fine movement shaft 35 are integrally formed, and fine movement focus handles 33 are provided at both ends of the fine movement shaft 35, respectively.
A precision screw 56 a is formed on the screw shaft 56, and converts the rotation of the fine movement focus handle 33 into the reciprocation of the piston 54 via the ball 55.

A coil spring 57 is disposed inside the front cylinder 51 and urges the piston 54 so as to abut the screw shaft 56. An oil inlet / outlet 58 is provided in the rear cylinder 52, and is connected to the cylinder 20 by the hose 45. A coil spring 59 is disposed between the fine focus handle 33 and the coarse focus handle 30 to position the both in the thrust direction. Reference numeral 60 denotes a support, and the rear barrel 52 is fixed to the coarse movement focus handle 30. The size of the oil chamber b1 of the operation side unit and the size of the oil chamber b on the cylinder side can be set at an appropriate ratio. Next, the operation of the coarse / fine movement mechanism will be described.

At the time of the coarse movement operation for rough focusing on the sample, the coarse movement focus handle is used. In FIG.
When the coarse focus handles 30, 30 are turned, the pinion 31a of the pinion shaft 31 and the rack 18 mesh with each other.
The coarse movement guide 16, the cylinder 20, and the revolver table 14 move integrally along the optical axis Z, and can move the objective lens 11 roughly up and down. In this case, the vertical movement amount of the objective lens required for focusing only needs to be about 50 mm, and if the pinion shaft is about 20 mm in diameter, the rotation amount of the coarse movement focus handle for obtaining a full stroke can be suppressed to one rotation or less. In addition, it is possible to prevent the hose 45 of the fluid driving device from wrapping around the pinion shaft 31.

The total weight of the revolver 10, the objective lens 11, and the revolver stand 14 is added to the pinion via the rack,
The backlash is removed, but the fixing force for resisting the rotational force generated on the pinion shaft by these weights is similar to a conventionally known method.For example, a constant slip torque is applied to the pinion shaft by a thrust force by a Sara spring or the like. Is possible. Next, the function of fine focus adjustment by the fluid driving device will be described.

In FIG. 2, fine focus handle 3
When the screw 3 is rotated forward (or reversely), the screw shaft 56 moves leftward (rightward) according to the pitch of the screw 56a provided on the screw shaft 56. The piston 54 also moves to the left while compressing the coil spring 57 via the ball 55 that eliminates the influence of the runout of the screw shaft. As a result, the oil in the oil chamber b1 is discharged from the inlet / outlet 58 and passes through the hose 45. , Flows into the oil chamber b of the cylinder 20. The piston 23 pushes the revolver table 14 upward by the oil that has flowed in. During these operations, the coarse movement focus handles 30, 30 are stopped by the thrust force of the Sarah spring or the like. For this reason, the coarse movement guide 16 is fixed, and only the pure driving force of the piston 23 in the optical axis direction acts on the revolver table 14, so that the eccentricity error in the direction perpendicular to the optical axis in the fine movement operation is extremely small.

Further, by appropriately selecting the volume ratio between the oil chamber b of the cylinder 20 and the oil chamber b1 of the operation side unit 20a and the screw pitch of the screw shaft 56, the amount of movement of the piston 23 per rotation of the fine movement handle is determined. You. For example, oil chamber b,
The volume ratio of b1 is 1: 1 and the screw pitch of the screw shaft is 0.1.
If a scale of 400 mm is engraved on the fine focus handle at 2 mm, the movement of the piston 23 per scale is 0.5.
μ is obtained. Assuming that the volume ratio b: b1 of the oil chamber is 2: 1, the movement of the piston 23 per scale is 0.25 μ.

A coil spring 25 connecting the revolver table 14 and the coarse movement guide 16 applies a constant preload to the piston 23 to improve the position accuracy and responsiveness of the piston expansion and contraction. If the weight is too heavy, the weight balance can be improved by arranging the coil spring 25a shown by the dotted line as shown in the figure and acting as a compression coil spring.

This fluid driving device transmits a driving force through a fluid such as oil or water, so that a damping effect due to the viscosity of the fluid can be obtained, and fine movement focusing by an electro-mechanical conversion mechanism using a piezo element. The response speed can be improved as compared with the mechanism. Motorization of fine focus adjustment is performed by using a stepping motor (not shown) on the fine focus handle 33 on the side where the hose 45 does not come out.
And so on.

As described above, in this embodiment, an inverted microscope has been described as an example. However, the present invention can be similarly applied to an upright microscope. That is, since the objective lens, the revolver, and the revolver stage are merely replaced with stages on which the sample is placed, the other configurations can be made exactly the same.

In the present invention, the fine focus handle by the fluid driving device is arranged coaxially with the coarse focus handle, and a pair is arranged. However, the operation unit may be arranged anywhere. For example, it is also possible to take out only the fine focus handle and place it at an independent position away from the microscope.

[0028]

As described above, according to the present invention, by providing a fine movement drive device such as a fluid drive device for fine movement and providing a rack pinion for coarse movement, the coarse movement stroke can be reduced to the drive stroke of the fine movement drive device. Is not limited to
A large coarse stroke can be taken. The rack pinion for coarse movement is provided on the coarse movement table, and the component force in the direction perpendicular to the moving direction generated by the gear pressure angle of the rack pinion acts only on the coarse movement table and is separate from the coarse movement table. Since it does not act directly on the fine moving table, the eccentricity error at the time of coarse moving of the fine moving table can be made extremely small.Moreover, since the fine moving drive device generates a driving force only in the moving direction, the Can be extremely small.

[0029]

Since the fluid drive unit can obtain an accurate reduction ratio by the fluid volume ratio between the drive side and the driven side, the reproducibility of the position can be 0.5 μm or less. Therefore, higher accuracy can be obtained as compared with the conventional fine movement mechanism using a gear train.

Since the fluid driving device uses oil or water to transmit the driving force, the fluid driving device has an effect of removing damping generated when a relatively heavy revolver or stage is driven up and down. This can be shortened as compared with the case of driving the element, and the recording of the video rate becomes possible in the sectioning in the optical axis direction.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically showing a coarse / fine movement mechanism of a microscope according to the present invention.

FIG. 2 is an enlarged view showing a fine movement mechanism in the coarse / fine movement mechanism shown in FIG. 1;

FIG. 3 is a diagram showing an overall configuration of a conventional microscope.

FIG. 4 is an enlarged view showing a rack and a pinion in the microscope shown in FIG. 3;

[Explanation of symbols]

11 ... objective lens, 13 ... stage, 20 ... cylinder,
30: coarse focus handle; 33: fine focus handle

Claims (5)

(57) [Claims] 1. A coarse / fine movement mechanism of a microscope for focusing by moving / moving an objective lens or a stage coarsely / finely in an optical axis direction of the objective lens, wherein the mechanism moves in the optical axis direction integrally with the objective lens or the stage. A fine moving table, a coarse moving table movable in the optical axis direction and arranged in series with the fine moving table, and a coaxial so as to move both the fine moving table and the coarse moving table in the optical axis direction. A movable guide provided between the fine moving table and the coarse moving table, and capable of extending and contracting in the optical axis direction; and the coarse moving table for coarsely driving the coarse moving table. A rack and pinion mechanism, wherein the coarse and fine movement tables are coarsely moved integrally in the optical axis direction by the rack and pinion mechanism, and the cylinder and the coarse movement table are expanded and contracted with respect to the coarse movement table. The fine table Microscopic coarse / fine movement mechanism characterized by fine movement. 2. The coarse / fine movement mechanism for a microscope according to claim 1, wherein a spring for applying a force for compressing the cylinder is provided between the coarse movement table and the fine movement table. 3. A fine movement operation unit for driving the cylinder and a coarse movement handle for driving the rack and pinion mechanism, wherein the fine movement operation unit is arranged coaxially with the coarse movement handle. The coarse and fine movement mechanism of the microscope according to claim 1. 4. A coarse / fine movement mechanism of a microscope for performing focus adjustment by coarsely / finely moving an objective lens or a stage in an optical axis direction of the objective lens, wherein the mechanism moves in the optical axis direction integrally with the objective lens or the stage. A fine moving table, a coarse moving table movable in the optical axis direction and arranged in series with the fine moving table, and a coaxial so as to move both the fine moving table and the coarse moving table in the optical axis direction. A fine guide driving device that is provided between the fine moving table and the coarse moving table and generates a driving force only in the optical axis direction; and the coarse movement for coarsely driving the coarse moving table. A rack and pinion mechanism provided on the table, wherein the coarse and fine movement tables and the fine movement table are coarsely moved integrally in the optical axis direction by the rack and pinion mechanism, and the fine movement driving device moves the coarse movement table with respect to the coarse movement table. The fine adjustment table A coarse and fine movement mechanism of a microscope characterized by moving. 5. A coarse / fine movement mechanism of a microscope for performing focus adjustment by coarsely / finely moving an objective lens or a stage in an optical axis direction of the objective lens, wherein the mechanism moves in the optical axis direction integrally with the objective lens or the stage. A fine movement table, and a cylinder of a fluid drive device for finely moving the fine movement table in the optical axis direction, wherein a fine movement operation unit for driving the cylinder is coaxially arranged with a coarse movement handle for performing a coarse movement operation. A coarse and fine movement mechanism for a microscope.