JPH10161038A - Microscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the microscope which can be put in focus even if the focus position shifts when a sample is replaced or if a revolver is rotated at an out-of-focus position. SOLUTION: A control circuit 10 outputs a command signal 30a for updating data stored in an objective data storage part 3 when an operator presses an offset switch 20, and corrects focusing positions of objectives stored in the objective data storage parts 3 according to the quantity of variation from the focusing position stored in the objective data storage part 3 when the offset switch 20 is pressed to the focusing position when the command signal 30a is inputted.

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 having an electric revolver and an electric focusing mechanism.

[0002]

2. Description of the Related Art A conventional microscope includes a motorized focusing device, a storage unit for storing a focusing position of an objective lens, and an input unit for inputting a focusing position according to the height of a sample. Things are known. As another conventional microscope, first, the focus position of one objective lens is stored in a storage unit as a reference position [0], and then the focus position of the objective lens serving as the reference and the focus position of another objective lens are stored. Is stored in the storage unit sequentially as position data, and the vertical position of each objective lens is determined based on the difference between the reference objective lens and another objective lens, thereby changing the sample and changing the height of the focus position. Japanese Patent Application Laid-Open No. 3-15015 discloses a configuration in which the objective lens is moved to a focus position when the objective lens is switched by a revolver.

[0003]

However, in the microscope described above, when the specimen is exchanged for one having a different thickness, in order to cope with a change in the focus position, it is necessary to re-input the focus position each time the specimen is exchanged. there were.

[0004] In addition, when an objective lens having a large depth of focus is used in the microscope described above, and the observation is performed at the end of the depth of focus and then the objective lens is switched to a shallow depth of focus, so-called out-of-focus due to poor focusing occurs. There was a problem.

For example, an objective lens with a magnification of 4 × and a magnification of 10
When using an X objective lens, the depth of focus of a 4 × objective lens is ± 16 μm and the depth of focus of a 10 × objective lens is ± 3 μm. After observation at the position of 16 μm on the edge of
When switching to a 10 × magnification objective lens,
The focal depth of the objective lens deviates from the range of ± 3 μm, resulting in an out-of-focus image.

In particular, as the objective lens has a high magnification of 60 × or 100 ×, the specimen is shifted from the focus position by more than 10 μm, and the blur of the image tends to be strong, so that the focusing cannot be performed. Sometimes.

The distance from the front end of the objective lens to the specimen surface (generally, the cover glass surface) when focusing is called a WD (working distance). An objective lens having a large WD is used. If the focus is not adjusted and the objective lens is switched to a small WD while approaching the sample, the image may be out of focus.

For example, when a sample is exchanged at a position where an objective lens having a magnification of 10 × is in the optical path, and the objective lens is switched to a 20 × magnification without performing focusing, a magnification of 10 ×
The WD of the × objective lens is 16 mm, and the WD of the 20 × objective lens is 2.1 mm, so that the 10 × magnification lens is used.
With the objective lens having a magnification of 20 mm, the specimen is moved out of the focusing position and approached so as not to hit the tip of the objective lens.
When switching to the X objective lens, the image may be out of focus.

The present invention has been made in view of such circumstances, and the focus can be adjusted even when the focus position is changed by exchanging a sample or when the revolver is rotated without being in the focus position. An object of the present invention is to provide a microscope capable of obtaining a focused image.

[0010]

According to a first aspect of the present invention, there is provided a focusing apparatus for a microscope apparatus, comprising: a plurality of objective lenses which are switched by an electric revolver; and a distance between the objective lens and a specimen. Changing electric focusing mechanism,
An objective lens data storage unit that stores a focusing position of the electric focusing mechanism corresponding to each of the plurality of objective lenses; and, when the objective lens is switched, the objective lens corresponding to the switched objective lens. A microscope provided with a control circuit for controlling the electric focusing mechanism so as to be in the focusing position stored in the data storage unit. An operation member that outputs a command signal for updating data, wherein the control circuit changes a focus position stored in the objective lens data storage unit to a focus position when the command signal is input; The focus positions of the plurality of objective lenses stored in the objective lens data storage unit are corrected based on the amount.

When the focus position changes by exchanging the sample, the focus position is determined from the new focus position when a command signal is input from the operator and the focus position stored in the objective lens data storage unit. The amount of change in the position is calculated, and the focus positions of the plurality of objective lenses stored in the objective lens data storage unit are corrected based on the calculation result, so that the focus shift between the objective lenses caused by sample exchange is corrected. Can be.

According to a second aspect of the present invention, in the microscope according to the first aspect, the control circuit performs the correction only when an objective lens having a magnification of 10 times or more is used.

By performing correction only when an objective lens having a magnification of 10 or more is used, it is possible to suppress the shift of the focus position to 10 μm or less, and to focus an image even when using an objective lens having a high magnification. Becomes possible.

[0014]

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

FIG. 1 is a block diagram of a focusing device used in a microscope according to a first embodiment of the present invention, and FIG. 2 is a diagram showing an example of an input method of objective lens data.

The focusing device 1 includes a data input unit 20, an objective lens data storage unit 3, a control circuit 10, a revolver 4
0, revolver changeover switch 4, revolver drive motor 6, revolver drive circuit 7, sensor 8, stage 1
4, stage drive motor 16, and stage drive circuit 1
7, sensor 18, offset switch (operation member)
30.

The data input unit 20 inputs objective lens data such as the magnification, WD, NA (numerical aperture), and parfocal length (distance from the focal position of the objective lens to the body surface) of the objective lens attached to the revolver 40. The input data is stored in the objective lens data storage unit 3.

As shown in FIG. 2, for example, data such as the magnification of an objective lens represented by a bar code 21 on a predetermined sheet is read by a bar code reader 22 or a ten key ( (Not shown), or by reading data stored in advance in the objective lens data storage unit 3.

The control circuit 10 stores the focus position of the objective lens when the revolver changeover switch 4 is depressed in the data table 3a of the objective lens data storage section 3, and based on a command from the revolver changeover switch 4, By controlling the energization of the motor 7 and rotating the motor 6 in a predetermined direction, the plurality of objective lenses attached to the revolver 40 are sequentially positioned on the optical path.

The control circuit 10 controls the energization of the drive circuit 17 to rotate the motor 16 in a predetermined direction and to move the stage 14 in the direction of the optical path.

When operated by an operator, the offset switch 30 outputs a command signal 30a for updating data stored in the objective lens data storage unit 3.
When the command signal 30a is input, the control circuit 10 corrects the focus position data stored in the objective lens data storage unit 3 based on the amount of change in the thickness of the specimen.

The sensor 8 detects which objective lens is on the optical path, and the sensor 18 detects the position of the stage 14 in the optical axis direction.

The electric focusing mechanism 50 is composed of the stage 14, the motor 16, the drive circuit 17, and the sensor 18.

3 to 5 are diagrams for explaining the relationship between the height of the objective lens and the specimen, and FIG. 6 is a flowchart for explaining the procedure for offsetting the focusing device of the microscope. In addition,
In FIG. 6, S1 to S13 indicate each step.

FIG. 3A shows the relationship between the objective lens 41 having a magnification of 4 × and the sample 5, FIG. 3B shows the relationship between the objective lens 42 having a magnification of 10 × and the sample 5, and FIG. 3 shows the relationship between the objective lens 43 having a magnification of 20 × and the sample 5, and FIG. 3D shows the relationship between the objective lens 44 having a magnification of 40 × and the sample 5.

Here, an upright microscope in which the stage moves up and down will be described as an example. The specimen 5 includes a slide glass 5a and a cover glass 5b.

Each of the objective lenses 41 to 44 is connected to a revolver 4
0 (see FIG. 1), if the focus position error between the objective lenses 41 to 44 is large, the image will be blurred. Therefore, the parfocal distance (the distance between the body surface of the objective lens and the focal position) (Distance) D, A, B, C are set within a predetermined range.

The parfocal distance differs depending on the objective lens.
This difference is the difference between the focus positions. In FIG. 3, the parfocal distance is shorter for a 4 × objective lens, longer for a 20 × objective lens, and the same for a 40 × objective lens, compared to a 10 × objective lens.

A procedure for offsetting with the above state as an initial state will be described.

For example, when the objective lens 43 having a magnification of 20 × is in the optical path, the revolver position at this time is confirmed by the sensor 8 (S1).

The control circuit 10 reads the focusing position data FA corresponding to the confirmed revolver position from the data table 3a (S2).

The sample 16 is moved to a predetermined position (focusing position) by driving the motor 16 via the driving circuit 17 based on the data FA (S3).

Thereafter, the specimen 5 is manually checked while viewing the image.
Is moved up and down to perform focusing (S4).

When the specimen 5 is replaced with a thick one, the offset switch 30 is pressed (S5), and a command signal 30a for updating the data stored in the data table 3a is output.

When the offset switch 30 is pressed, the current focus position data FN is read by the sensor 18 (S6).

Note that the use of an objective lens having a magnification of 10 or more can suppress the shift of the focus position to 10 μm or less, so that the correction is performed using an objective lens having a magnification of 10 or more. WD of 16 × objective lens is 16
mm, whereas the depth of focus is as shallow as ± 3 μm.
This is because it is easy to focus, and the focused position is within a range that does not blur much even with a high-magnification objective lens (see FIG. 4).

Next, the difference (change amount) FD between the previous focus position data FA and the current focus position data FN is calculated (S).
7).

The difference FD is added to the focusing position data of the objective lenses 41 to 44 in the data table 3a to correct the data table 3a (S8). This operation completes the update of the focus position data.

FIG. 5 shows a state in which the sample 5 has been moved based on the updated data table 3a. At this time,
The parfocal distances of the objective lenses 41 to 44 are D, A, B, and C, respectively, as in FIG.

When the revolver changeover switch 4 is pressed when the offset switch 30 is not pressed (S9), the current reference position data FB is read (S10).

This data FB is input to the data table 3a as the focus position of the objective lens 43 having a magnification of 20 ×,
The data of the focusing position of the objective lens 43 having a magnification of 20 ×
To FB (S11).

The revolver 40 is rotated (S12) to switch to, for example, a 10 × magnification objective lens.

After the revolver 40 stops, the position of the revolver is confirmed by the sensor 8 (S13).

Thereafter, focusing position data corresponding to the confirmed revolver position is read from the data table 3a,
The specimen 5 is moved to a predetermined position (focus position) based on the focus position data.

According to this embodiment, the following effects can be obtained. Even when the focus position changes by exchanging the sample 5 (may change by about 0.7 mm depending on the combination of the slide glass 5a and the cover glass 5b),
Since the focus shift between the objective lenses 41 to 44 is corrected, the revolver 4
When the objective lenses 41 to 44 are switched by rotating 0, an in-focus image can be obtained. When the observer presses the offset switch 30, the position of the sample 5 corresponding to the objective lenses 41 to 44 is determined, so that the objective lenses 41 to 4 can be adjusted without focusing.
Even when 4 is switched, the specimen 5 moves to a position corresponding to the objective lenses 41 to 44, and an in-focus image can be obtained. Since the distance between the sample 5 and the objective lenses 41 to 44 can be properly maintained, it is possible to prevent the sample 5 from contacting the objective lenses 41 to 44 and to prevent the sample 5 from being broken. An objective lens with a very deep depth of focus (for example, a magnification of 0.
Correction with a focal depth of 5 × ± 0.4 mm) is avoided, so that contact with the sample at the time of switching the objective lens can be prevented. When the focus position detection is performed on the microscope side together with the autofocus, the range of the depth of focus of the objective lenses 41 to 44 is determined as the focus position, but the objective lenses 42 to 44 having a magnification of 10 or more are used. , The focus position is not so blurred even with the objective lenses 42 to 44 having a high magnification, and the focus position can be adjusted.

[0046]

As described above, according to the microscope of the first aspect of the present invention, the focus shift between the objective lenses caused by the exchange of the specimen can be corrected, so that the focus position changes by exchanging the specimen. Or when the revolver is rotated out of focus, an in-focus image can always be obtained.

According to the microscope of the second aspect of the present invention,
By performing correction only when an objective lens having a magnification of 10 or more is used, the focus position can be adjusted even when switching to any objective lens. It is possible to focus an image even when the objective lens is used.

[Brief description of the drawings]

FIG. 1 is a block diagram of a focusing device used in a microscope according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating an example of an input method of objective lens data.

FIG. 3 is a diagram illustrating the relationship between the height of an objective lens and a specimen.

FIG. 4 is a diagram for explaining a height relationship between an objective lens and a specimen.

FIG. 5 is a diagram for explaining the relationship between the height of the objective lens and the specimen.

FIG. 6 is a flowchart illustrating a procedure for offsetting the focusing device of the microscope.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Focusing device 3 Objective lens data storage part 10 Control circuit 20 Offset switch (operation member) 40 Electric revolver 50 Electric focusing mechanism

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Masahiko Otomo 3-2-3 Marunouchi, Chiyoda-ku, Tokyo Nikon Corporation (72) Inventor Hiroko Saito 3-2-2, Marunouchi, Chiyoda-ku, Tokyo Stock Company Nikon company

Claims (2)

[Claims] 1. A plurality of objective lenses switched by an electric revolver, an electric focusing mechanism for changing a distance between the objective lens and a sample, and a focusing of the electric focusing mechanism corresponding to each of the plurality of objective lenses. An objective lens data storage unit for storing a position, and the electric focusing so that, when the objective lens is switched, the focusing position stored in the objective lens data storage unit corresponds to the switched objective lens. A microscope provided with a control circuit for controlling a mechanism, comprising: an operation member that, when operated by an operator, outputs a command signal for updating data stored in the objective lens data storage unit; The control circuit is configured to control the pair based on an amount of change from the focus position stored in the objective lens data storage unit to the focus position when the command signal is input. Lenses each focusing position microscope and corrects the plurality of objective lenses stored in the data storage unit. 2. The microscope according to claim 1, wherein the control circuit performs the correction only when an objective lens having a magnification of 10 or more is used.