JPH09211335A - Focusing mechanism for microscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a focusing mechanism for a microscope capable of rapidly and easily performing operation from specimen change to focusing. SOLUTION: When the sensor board 3b of a moving body 3 is positioned within a specified range and interrupts a photointerruptor 16, '0' output occurs. When a stage largely retreats by the specimen change, etc., the position of the sensor board 3b is off from a range H and the interruption of the photointerruptor is eliminated, '1' output occurs. A pulse converter 14 generates output with smaller ratio than that of the pulse output of a rotary encoder 15 in accordance with the operation of a focusing operation handle when the '0' output is given from the photointerruptor 16, and the converter 14 generates the output with larger ratio than that of the pulse output of the rotary encoder 15 when the '1' output is given from the photointerruptor 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a focusing mechanism for focusing an observation sample on a microscope.

[0002]

2. Description of the Related Art Conventionally, as a focusing mechanism of a microscope, as shown in FIG. 3, a system of vertically moving a stage system by combining a rack and a pinion has been widely used.

In this case, reference numeral 30 in the drawing denotes a focusing portion main body fixed to a mirror body 31, 32 denotes a focusing portion main body 3 by a guide 33.
A movable body supported so as to be vertically movable with respect to 0, a rack fixed to the movable body 32, a pinion shaft 35 rotatably supported by the focusing unit body 30, and a pinion shaft 35.
It is a focusing operation handle arranged coaxially with.

Further, 37 is a stage for mounting the sample S,
Reference numeral 38 is a stage holder that carries the stage 37 and is positioned and fixed to the movable body 32, and 39 is a condenser held by the stage holder 38 via a condenser holder 39a.

Further, 40 holds an objective lens 41,
A revolver attached to the tip of the arm portion 31a of the lens body 31, 42 is a lens barrel attached to the upper portion of the arm portion 31a of the lens body 31, 43 is an eyepiece lens attached to the binocular portion of the lens barrel 42, and 44 is A light source mounted on the lower back of the mirror body 31,
An illumination optical system 45 guides the light from the light source 44 to the condenser 39.

When the light source 44 is turned on, the light source 4
The illumination light emitted from 4 is guided to the condenser 39 via the illumination optical system 45, is condensed by the condenser 39, and illuminates the sample S on the stage 37.

When the focusing operation handle 36 is manually rotated from this state, the pinion shaft 35 and the rack 34 are operated.
The movable body 32 is moved up and down via the stage 37, and the stage 37 is moved up and down together therewith, so that the specimen S is focused, and the observation image of the specimen S is passed from the objective lens 41 through the lens barrel 42 to the eyepiece 43. It is observable.

However, in such a manual focusing mechanism, the focusing operation by the manual rotation operation of the focusing operation handle 36 is performed at a constant speed. Therefore, in the case where there is a sufficient distance to the focus position. However, there is a problem in that the operation takes time and the operation of the handle for this is troublesome.

For this reason, in recent years, instead of such a manual focusing mechanism, an electrically-operated one which is configured to be linked with an actuator such as a stepping motor has been considered.

However, even for such a focusing mechanism,
Focusing by rotating the focusing operation handle 36 is performed at a constant speed, so that the operation takes time when the focus position is sufficiently distant.
Therefore, it is conceivable to increase the operating speed by increasing the rotation speed of the stepping motor, but this makes it difficult to stop the focus accurately at the focus position, and there is a problem that it takes time to adjust the focus position. It was

As described above, in the conventional focusing mechanism, the focusing is performed at a constant speed regardless of the manual operation and the automatic operation. Therefore, it is difficult to perform the focusing quickly and efficiently.

Therefore, in the past, Japanese Patent Publication No. 63-56961
As disclosed in Japanese Patent Publication No. JP-A-5-87804, in driving control in automatic focusing, the driving speed is changed depending on whether or not the photographing lens is within a predetermined range near the focal point. As disclosed in the publication, in drive control in automatic focusing, when image information for focus detection cannot be obtained at the time of starting a focusing operation, the stage is moved to a reference position provided near the focus in advance. It is also considered that the subject is made to focus and then focused.

However, according to such a focusing mechanism,
Compared with the case where the focusing speed is constant, it becomes possible to focus quickly and efficiently.

[0014]

By the way, the shape of a sample on a stage of a general microscope is such that a sample is placed on a slide glass having a thickness of 1 mm and sandwiched by a thin cover glass. At the time of replacement, the stage is once lowered largely, and then raised again to near the point of focus so that focusing is performed.

However, in the conventional method, the focus of the sample is only rapidly and there is no consideration for the sample exchange. No mention is made of driving from the lower end to the focus position, and a quick operation from the exchange of these specimens to the focusing is desired.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a focusing mechanism for a microscope, which can quickly and easily perform operations from sample exchange to focusing. .

[0017]

According to the first aspect of the present invention,
Operating means for generating an operation signal for adjusting the distance between the objective lens and the sample mounting stage; driving means for driving the objective lens or the sample mounting stage to change the distance between the two; A drive control unit that generates a drive signal at a predetermined ratio and outputs the drive signal to the drive unit, and a detection unit that detects whether or not the distance is within a predetermined range near the in-focus position of the sample. The drive control means changes the ratio of the drive signal to the operation signal based on the detection result of the detection means and outputs the changed drive signal to the drive means.

According to a second aspect of the present invention, in the first aspect, the drive control means outputs a drive signal of a small ratio to the operation signal to the drive means when the detection means detects a predetermined range. However, when the detection means detects the outside of the predetermined range, a drive signal having a large ratio with respect to the operation signal is output to the drive means.

According to a third aspect of the present invention, an operating means for generating an operation signal for adjusting the distance between the objective lens and the sample mounting stage, and the objective lens or the sample mounting stage are driven to drive both of them. Driving means for changing the distance, driving control means for outputting a driving signal to the driving means based on the operation signal, and detecting whether or not the distance is within a predetermined range near the focus position of the sample. And a detection means, the drive means, based on the detection result of the detection means, when it detects that the distance has changed from within the predetermined range out of the range, the drive is driven so that the distance becomes maximum,
When an operation signal is generated from the operation means, the driving is performed so that the distance is within the predetermined range.

As a result, according to the invention of claim 1,
It is detected whether or not the distance between the objective lens and the sample mounting stage is within a predetermined range near the focus position of the sample, and the ratio to the operation signal for adjusting the distance is changed based on the detection result. Further, since the drive signal is output to the drive means, the stage moving speed in the vicinity of the in-focus position of the sample and the stage moving speed at the time of exchanging the sample can be changed.

According to the second aspect of the present invention, if the distance is within a predetermined range, a drive signal to the drive means having a small ratio to the operation signal is output, and if the outside of the predetermined range is detected, the operation signal is output. On the other hand, since a drive signal for a large proportion of driving means is output, the stage can be moved at a low speed near the in-focus position of the sample, and the stage can be moved at a high speed when exchanging the sample. become.

According to the third aspect of the present invention, when it is detected that the distance between the objective lens and the sample mounting stage has changed from within a predetermined range near the focus position of the sample to outside the range, the maximum distance is detected. When the operation signal is generated from the operation means in this state, the distance is within the predetermined range, so that the maximum distance of the stage during sample exchange is The movement can be swift, and the subsequent return to a predetermined range near the in-focus position can be swiftly performed.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) FIG. 1 shows a schematic structure of a focusing mechanism of a microscope to which the present invention is applied. In the figure, 1
Is a mirror body of a microscope, and the focusing unit main body 2 is fixed to the mirror body 1. The focusing unit main body 2 forms a pedestal 2 a that projects at a right angle to the side surface of the mirror body 1.

A movable body 3 is supported on the focusing unit body 2 via a linear guide 4 so as to be vertically movable. In this case, a ball guide, a cross roller guide, or the like is used as the linear guide 4.

On this movable body 3, a stage holder 5 carrying a stage (not shown) on which a specimen to be observed is placed.
Is provided, the stage holder 5 is integrally moved up and down as the movable body 3 moves in the vertical direction, and the distance between the objective lens and the sample mounting stage is adjusted.

The movable body 3 is the base 2 of the focusing unit body 2.
A hole 3a is provided on the end face facing a, and a nut 6 is fitted into the opening of the hole 3a. The nut 6 is to be screwed with a screw portion 10a of a ball screw shaft 10 described later.

On the other hand, a motor support base 7 is provided on the pedestal 2a of the focusing unit main body 2, and a stepping motor 8 is provided on the motor support base 7. Then, the rotary shaft 8a of the stepping motor 8 is introduced into the hollow portion 7a of the support base 7, and the ball screw shaft 10 is connected to the end of the rotary shaft 8a via a coupling 9. Here, as the coupling 9, there is no flexible coupling capable of absorbing eccentricity or declination between both shafts, or there is no backlash and the reaction force to the shaft is small even when there is eccentricity or declination between both shafts. Oldham type couplings that can be used are used.

The ball screw shaft 10 is used for the linear guide 4
It has a threaded portion 10a and a non-threaded portion 10b, the end of the non-threaded portion 10b is formed in the large diameter portion 101, and the end portion on the large diameter portion 101 side is a self-aligning ball. The bearing 11 is vertically supported in a cantilever manner, and the screw portion 10a is screwed to the nut 6. That is, the ball screw shaft 10 is
It is rotatably supported by the self-aligning ball bearing 11 in a state where the position is regulated in the vertical direction, and the rotation of the stepping motor 8 is transmitted to the nut 6 via the screw portion 10a.

In this case, the screw portion 10 of the ball screw shaft 10
A large number of balls 12 are interposed between the screw grooves provided in each of a and the nut 6 so that the screw portion 10a and the nut 6 are in rolling contact when the ball screw shaft 10 rotates.

Reference numeral 13 denotes a driver for driving the stepping motor 8, and the driver 13 is capable of varying the rotation speed of the stepping motor 8 according to the number of pulses output from the pulse converter 14.

A rotary encoder 15 and a photo interrupter 16 are connected to the pulse converter 14. Here, the rotary encoder 15 is incorporated in a focusing operation handle (not shown) and generates a predetermined pulse output according to the operation of the focusing operation handle.
Further, the photo interrupter 16 is for detecting the position of the movable body 3, and is adapted to generate a binarized signal depending on whether or not it is blocked by the sensor plate 3b provided integrally with the movable body 3. .

In this case, for example, when the stage on which the sample is placed is near the focus, the sensor plate 3b of the movable body 3 is
When the photo interrupter 16 is located within a predetermined range H and interrupts the photo interrupter 16, a "0" output is generated, the stage retreats significantly due to sample exchange, etc., and the position of the sensor plate 3b deviates from the range H,
When the interruption of the photo interrupter 16 disappears, "1" output is generated.

When the photo interrupter 16 gives "0" output, the pulse converter 14 generates an output of a predetermined ratio with respect to the pulse output of the rotary encoder 15 according to the operation of the focusing operation handle. And again
When a "1" output is given from the photo interrupter 16, an output with a changed ratio to the pulse output of the rotary encoder 15 is generated. For example, when the photo interrupter 16 outputs “0”, “10” is output for one pulse from the rotary encoder 15.
When the photo interrupter 16 outputs “1”, the output of a small ratio of about 100 is generated for a pulse of the rotary encoder 15 of about 100. There is.

However, according to this structure, when the driver 13 rotates the stepping motor 8,
Ball screw shaft 1 through rotating shaft 8a and coupling 9
Rotation is transmitted to 0. Then, when the ball screw shaft 10 is rotated, the screw portion 10a is rotated in the nut 6, whereby the movable body 3 is guided by the linear guide 4 and moved in the vertical direction together with the nut 6, and the stage moves up and down. Be moved.

Here, when the stage on which the sample is placed is near the focus and the sensor plate 3b of the movable body 3 is at the solid line position in the drawing, the photo interrupter 16 outputs "0", so that The pulse converter 14 generates a small proportion of the pulse output of the rotary encoder 15 according to the operation of the focusing operation handle, and the driver 1
Give to 3.

As a result, the driver 13 drives the stepping motor 8 to rotate at a low speed, and the movable body 3 is also guided by the linear guide 4 to move at a low speed in the vertical direction. That is, when the stage on which the sample is placed is near the focus and the sensor plate 3b of the movable body 3 is at the solid line position in the drawing within the predetermined range H, the stage is moved at a low speed in response to the operation of the focusing operation handle. Can be driven vertically.

On the other hand, when the stage is far from the focus, the sensor plate 3b of the movable body 3 is released from the interruption of the sensor plate 3b of the movable body 3 and the photo interrupter 16 outputs "1". The pulse converter 14 includes a rotary encoder 15 corresponding to the operation of the focusing operation handle.
A large proportion of the pulse output is generated and given to the driver 13.

As a result, the driver 13 drives the stepping motor 8 to rotate at high speed, and the movable body 3 is also guided by the linear guide 4 to move vertically in high speed in the vertical direction. That is, when the stage on which the sample is placed is away from the vicinity of the focus and the sensor plate 3b of the movable body 3 is outside the predetermined range H, the stage is moved to the near-focus position at a high speed according to the operation of the focusing operation handle. Can be moved to. (Modification of First Embodiment) The pulse converter 14
When the photo interrupter 16 is released from being blocked by the sensor plate 3b and changes from "0" output to "1" output,
At this time, the output of a predetermined number of pulses is generated, and the movable body 3 is quickly lowered to the lowest position of the broken line in the drawing, that is, to the position where the retreat distance of the stage is maximum. Then, the pulse converter 14 generates a large proportion of output for one pulse of the rotary encoder 15 described above only when the movable body 3 is moved upward from the lowermost position of the broken line in the drawing, and the photo interrupter 16 is generated. The movable body 3 is raised until it is blocked by the sensor plate 3b.

In this way, for exchanging specimens,
When the photo interrupter 16 is lowered from the “0” output to the “1” output by lowering the stage and releasing the blocking of the photo interrupter 16 by the sensor plate 3b of the movable body 3,
A predetermined number of pulses are output from the pulse converter 14, and the movable body 3 is quickly lowered to the lowest position of the broken line shown in the drawing, that is, to the position where the retreat distance of the stage is maximum.

After that, when the sample exchange is completed and the focusing operation handle is operated to move the movable body 3 upward, one pulse of the rotary encoder 15 corresponding to the operation of the handle is output from the pulse converter 14. A large proportion of output is generated, given to the driver 13, and the movable body 3 is raised until the photo interrupter 16 is blocked by the sensor plate 3b.

As a result, the driver 13 drives the stepping motor 8 to rotate at high speed, and the movable body 3 is guided by the linear guide 4 to move upward at high speed. In other words, when returning from a state in which the stage is lowered by exchanging a sample to a position near the focus, the stage can be driven to near the focus at high speed according to the operation of the focusing operation handle.

(Second Embodiment) FIG. 2 shows a schematic configuration of the second embodiment. The same parts as those in FIG. 1 are designated by the same reference numerals.

In this case, the counter 17 is connected to the output end of the pulse converter 14, and the output applied to the driver 13 from the pulse converter 14 is counted to recognize the position of the movable body 3. That is, in the counter 17,
The origin position of the movable body 3 is set to "0", and the pulse given to the pulse driver 13 is counted from this time point, and the pulse converter 14 detects the current position of the movable body 3 from the count value of the counter 17. A driver 1 for determining whether this position is a coarse movement area or a fine movement area and rotationally driving the stepping motor 8 at a low speed or a high speed.
The output of 3 is set.

Therefore, in this way, the same effect as described above can be realized only by software processing, and the boundary between the coarse movement area and the fine movement area determined from the count value of the counter 17 can be freely set. You can also do it.

[0045]

As described above, according to the present invention, the operations from the sample exchange to the focusing can be performed quickly and easily, and the focusing of the microscope can be further enhanced. A mechanism can be realized.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of a first embodiment of the present invention.

FIG. 2 is a diagram showing a schematic configuration of a second embodiment of the present invention.

FIG. 3 is a diagram showing a schematic configuration of a focusing mechanism of a conventional microscope.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Mirror body, 2 ... Focusing part main body, 2a ... Pedestal, 3 ... Movable body, 3a ... Hole part, 3b ... Sensor plate, 4 ... Linear guide, 5 ... Stage holder, 6 ... Nut, 7 ... Motor support stand , 7a ... Hollow part, 8 ... Stepping motor, 8a ... Rotating shaft, 9 ... Coupling, 10 ... Ball screw shaft, 10a ... Screw part, 10b ... Non-screw part, 101 ... Large diameter part, 11 ... Self-aligning ball bearing , 12 ... Ball, 13 ... Driver, 14 ... Pulse converter, 15 ... Rotary encoder, 16 ... Photo interrupter, 17 ... Counter.

Claims (3)

[Claims] 1. An operating means for generating an operation signal for adjusting a distance between an objective lens and a sample mounting stage, and a driving means for driving the objective lens or the sample mounting stage to change the distance between them. A drive control means for generating a drive signal at a predetermined ratio with respect to the operation signal and outputting the drive signal to the drive means; and a detection for detecting whether or not the distance is within a predetermined range near the focus position of the sample. The focusing mechanism of the microscope, wherein the drive control means changes the ratio of the drive signal to the operation signal based on a detection result of the detection means and outputs the changed ratio to the drive means. 2. The drive control means outputs a drive signal of a small ratio to the operation signal to the drive means when the detection means detects a predetermined range, and when the detection means detects outside the predetermined range. The focusing mechanism of the microscope according to claim 1, wherein a drive signal having a large ratio with respect to the operation signal is output to the drive means. 3. An operating means for generating an operation signal for adjusting the distance between the objective lens and the sample mounting stage; and a driving means for driving the objective lens or the sample mounting stage to change the distance between them. And drive control means for outputting a drive signal to the drive means based on the operation signal, and detection means for detecting whether or not the distance is within a predetermined range near the focus position of the sample. When the drive unit detects that the distance has changed from within the predetermined range to outside the range based on the detection result of the detection unit, the drive unit drives so that the distance becomes maximum, and the distance is maximum. A focusing mechanism of a microscope, wherein when a manipulation signal is generated from the manipulation means, the focusing mechanism is driven so that the distance is within the predetermined range.