JP2001124995A - Scanning laser microscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve reliability by suppressing breakdown of a resonance type galvanomirror without limiting original functional operability, even if the reso nance type galvanomirror is used. SOLUTION: A sample 13 is irradiated with a laser beam 1 and scanned in the X and Y directions by resonance galvanomirror 22 and a galvanomirror 23, and the light from the sample 13 is detected to obtain an observation image of the sample 13, and the resonance galavnomirror 22 is stopped or its scanning angle is decreased, when specific operation is not conducted through an operation part 31 for a specific interval after processings, such as the adjustment of the luminance and contrast for two-dimensional image data by operation which is inputted from the operation part 31 or the scanning start, amplitude control, or scanning stop of the resonance type galvanomirror 22 and galvanomirror 23.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a scanning laser microscope in which a laser beam is scanned by a sample using a resonance type galvanometer mirror, and light from the sample is detected to obtain an image of the sample.

[0002]

2. Description of the Related Art FIG. 7 is a block diagram of an optical system of a scanning laser microscope.

[0003] Laser light 1 is output from a laser light source (not shown) which is considered to be equivalent to a point light source. This laser light 1 passes through the beam splitter 2 and enters the first optical deflector 3.

The first optical deflector 3 scans the laser beam 1 in the X direction of the two-dimensional scanning.
At a position conjugate with the pupil 5. When the first optical deflector 3 is not deflecting, the laser light 1 is transmitted along the optical axis 6.
Follow along. When the first optical deflector 3 is deflecting, that is, when scanning the laser beam 1 in the X direction, the first optical deflector 3 is provided at the pupil position. Direction coincides with the off-axis main optical axis 7, and the center of the laser beam 1 also coincides with the off-axis main optical axis 7.

Next, the laser beam 1 traveling along the optical axis 6 and the off-axis main optical axis 7 passes through two pupil transmission lenses 8 and 9 to a second optical deflector 10 arranged at the pupil position. Incident.
The second optical deflector 10 scans the laser beam 1 in the Y direction in two-dimensional scanning. However, in the drawing, for simplicity, both the XY directions are described in the same plane.

The laser beam 1 two-dimensionally scanned by the first and second optical deflectors 3 and 10 enters a pupil 5 of an objective lens 4 through a pupil projection lens 11 and an imaging lens 12. Then, these laser beams 1 generate point lights which are limited by diffraction on the sample 13 by the objective lens 4. At this time, the first and second optical deflectors 3 and 10 cause the laser beam 1 to perform two-dimensional XY scanning, so that the point light is two-dimensionally scanned by the sample 13.

[0007] The laser light reflected from the sample 13 (hereinafter referred to as reflected light) passes through the objective lens 4 and its pupil 5, and further forms an image once through the imaging lens 12. This imaging surface is a surface on which an image is observed with a normal optical microscope. Further, the reflected light returns to the second optical deflector 10 by the pupil projection lens 11.

[0008] As described above, the reflected light returns to the beam splitter 2 in exactly the same path as when it enters the sample 13, and the detection light 14 is separated by the beam splitter 2.

In this case, the reflected light from the sample 13
Since the light returns after passing through the first optical deflectors 10 and 3, the position of the detection light 14 does not move even when the off-axis main optical axis 7 is scanned.

The detection light 14 is converged by a condenser lens 15 in a point shape, passes through a pinhole 16 disposed in the point constricted position, and is detected by a detector 17 disposed behind the pinhole 16. . If an image of the sample 13 is obtained by processing the detection signal of the detector 17, an image having no flare and having a higher resolution than a normal microscope can be obtained. In addition,
It goes without saying that a normal image can be obtained without disposing the pinhole 16.

In a scanning laser microscope, there is a demand for observing a wide range as much as possible at a speed as close to real time as possible. To achieve this, a scanning laser microscope has been developed in which one or both of the first and second optical deflectors 3 and 10 employ a resonance type galvanometer mirror.

The resonance type galvanometer mirror enables the mirror section to vibrate at high speed over a wide range by using a resonance state determined by mechanically configured components.
For this reason, a large stress such as wear and torsion due to vibration is applied to the bearing portion and the shaft portion, resulting in poor durability.

Therefore, the scanning laser microscope using the resonance type galvanomirror has a problem that its reliability is inferior to long-term use. In order to solve this, for example, as described in JP-A-6-300974, three or more types of optical deflectors are provided, and two types of the optical deflectors are used depending on functional requirements. It is trying to improve the reliability of the device.

[0014]

However, a scanning laser microscope provided with three or more types of optical deflectors not only requires three or more types of optical deflectors, but also requires a large-scale optical system. It will be something.

When an optical deflector other than the resonance type galvanometer mirror is used, there is naturally a problem that the performance of the resonance type galvanometer mirror cannot be exhibited stably.

Accordingly, the present invention provides a highly reliable scanning laser microscope that reduces the load on the resonant galvanometer mirror without limiting the original operability even when the resonant galvanometer mirror is used. With the goal.

[0017]

A scanning laser microscope according to the present invention converts a laser beam output from a laser light source into a laser beam.
At least one is a resonance type and scans on a sample by two galvanometer mirrors scanning in directions perpendicular to each other, and detects light from this sample to obtain an image of the sample. At least processing operations on the image of the sample are performed. Operating means for inputting, and control means for stopping the operation of the resonance type galvanometer mirror or reducing the scanning angle if there is no operation input from the operating means for a certain interval after the processing for the operation input from the operating means is completed. And

The control means stops the operation of the resonance type galvanomirror or immediately reduces the scanning angle when the operation of the resonance type galvanomirror is stopped or the scanning angle is reduced and an operation input is made from the operation means. It has a function to return to the scanning state of the laser beam on the sample before the scanning and the state of processing for obtaining an image of the sample.

[0019]

(1) Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a configuration diagram of an optical system of a scanning laser microscope according to the present invention, and FIG. 2 is a partial block diagram.

An optical system 21 is arranged in the laser scanning microscope main body 20. The configuration of the optical system 21 will be described. The laser beam 1 passes through the beam splitter 2 and enters the resonance type galvanometer mirror 22.

The resonance type galvanometer mirror 22 scans in the X direction in two-dimensional scanning, and is arranged at a position conjugate with the pupil 5 of the objective lens 4. When the resonance type galvanometer mirror 22 does not deflect, the laser beam 1 travels along the optical axis 6 and the resonance type galvanometer mirror 22
When the laser beam 1 is deflected, that is, when the laser beam 1 is scanned in the X direction, the direction of the laser beam 1 is aligned with the off-axis main optical axis 7 because the resonance type galvanometer mirror 22 is provided at the pupil position. Accordingly, the center of the laser beam 1 also coincides with the off-axis main optical axis 7.

Next, two pupil transmission lenses 8 and 9 and a galvanomirror 23 are arranged on the optical path of the laser beam 1 traveling along the optical axis 6 and the off-axis main optical axis 7.

The galvanomirror 23 is arranged at the pupil position of the two pupil transmission lenses 8 and 9, and scans the laser beam 1 in the Y direction in two-dimensional scanning.
However, in the drawing, for simplicity, both the XY directions are described in the same plane.

A pupil projection lens 11, an imaging lens 12, and an objective lens 4 are arranged on the optical path of the laser beam 1 two-dimensionally scanned by the resonance type galvanometer mirror 22 and galvanometer mirror 23.

On the optical path of the detection light 14 extracted by the beam splitter 2, a condenser lens 15, a pinhole 16, and a photodiode 24 are arranged.

In such an optical system 21, the resonance type galvanometer mirror 22 and the galvanometer mirror 23 are driven for scanning by drive control units 25 and 26, respectively.

On the other hand, the computer 27 drives and controls the resonance type galvanometer mirror 22 and the galvanometer mirror 23 of the optical system 21 to scan the laser beam 1 on the sample 13, and transmits the light from the sample 13 at this time to the photodiode 24. To obtain a two-dimensional image of the sample 13, and an input / output unit 30 via a bus 29 to a main processing unit 28 comprising a CPU.
An input unit 32 to which the operation unit 31 is connected, an output unit 34 to which the monitor device 33 is connected, a program memory 35, a data memory 36, an image memory 37, and a timer 38 are connected.

The operation unit 31 controls brightness, contrast of an image displayed on the monitor device 33, starts scanning of the resonance type galvanometers 22 and 23, controls amplitude (controls the scanning angle), and stops scanning. It is provided with an operation end for operation setting.

The program memory 35 stores in advance programs relating to various processes such as image processing shown in FIG. 3 and programs relating to a control method of the resonance type galvanomirror 22 shown in FIG.

Accordingly, the main arithmetic processing unit 28 executes the program stored in the program memory 35 to execute the image processing input from the operation unit 31 and the processing of various settings for the resonance type galvanomirror 22 after the completion. The operation of the resonance type galvanometer mirror 22 is stopped or scanned with respect to the drive control unit 25 through the input / output unit 30 if there is no operation input from the operation unit 31 for a certain interval or more by monitoring the time from the end of processing by the timer 38. It has a function of issuing an instruction to reduce the angle.

Next, the operation of the laser scanning microscope configured as described above will be described.

The laser light 1 is output from a laser light source (not shown) equivalently considered as a point light source. This laser light 1 passes through the beam splitter 2 and enters the resonance type galvanometer mirror 22.

The resonance type galvanometer mirror 22 scans the laser beam 1 in the X direction in two-dimensional scanning. Here, when the resonance type galvanometer mirror 22 does not deflect, the laser beam 1 travels along the optical axis 6. When the resonance type galvanometer mirror 22 is deflecting, that is, when scanning the laser beam 1 in the X direction, the resonance type galvanometer mirror 22 is provided at the pupil position.
Direction coincides with the off-axis main optical axis 7, and the center of the laser beam 1 also coincides with the off-axis main optical axis 7.

Next, the laser beam 1 traveling along the optical axis 6 and the off-axis main optical axis 7 passes through two pupil transmission lenses 8 and 9 and is incident on a galvanomirror 23 arranged at the pupil position.
The galvanomirror 23 performs scanning in the Y direction in two-dimensional scanning.

The laser beam 1 scanned two-dimensionally by the resonance type galvanometer mirror 22 and the galvanometer mirror 23.
Enters the pupil 5 of the objective lens 4 through the pupil projection lens 11 and the imaging lens 12. Then, these laser beams 1 generate point lights which are limited by diffraction on the sample 13 by the objective lens 4. At this time, the laser beam 1 is changed to XY by the resonance type galvanometer mirror 22 and the galvanometer mirror 23.
By performing the two-dimensional scanning of
Is scanned two-dimensionally.

The reflected light from the sample 13 is transmitted to the objective lens 4
Then, the light passes through the pupil 5 and further passes through the imaging lens 12 to form an image once. This imaging surface is a surface on which an image is observed with a normal optical microscope. Further, the reflected light returns to the galvanometer mirror 23 by the pupil projection lens 11.

As described above, the reflected light returns to the beam splitter 2 in exactly the same path as when the light enters the sample 13, and the detection light 14 is separated by the beam splitter 2.

In this case, since the reflected light from the sample 13 returns through the galvanometer mirror 23 and the resonance type galvanometer mirror 22, even if the off-axis main optical axis 7 is scanned, the detection light 14
Does not move.

The detection light 14 is focused by a condenser lens 15 in a point shape, passes through a pinhole 16 arranged in a position narrowed in a point shape, and is received by a photodiode 24 arranged behind the pin hole 16. . This photodiode 24
Receives the detection light 14 and outputs the light reception signal.

The computer 27 takes in the light receiving signal from the photodiode 24 through the input / output unit 30 by the processing of the main arithmetic processing unit 28, processes this detection signal to obtain two-dimensional image data of the sample 13, and The two-dimensional image data is stored in the image memory 37, and the output unit 34
Through the monitor device 33 to display an observation image of the sample 13.

While the observation image of the sample 13 is displayed as described above, adjustment of the brightness and contrast of the image, start of the scanning of the resonance type galvanometers 22 and 23, amplitude control, scanning stop, etc. Is input, the computer 27 adjusts the brightness and contrast of the two-dimensional image data by the main processing unit 28 in step # 1 of the flowchart relating to the image processing shown in FIG. -22
Then, processing such as scanning start, amplitude control, and scanning stop of the galvano mirror 23 is executed, and the two-dimensional image data after the image processing at this time is transmitted to the monitor device 33 through the output unit 34.

The monitor device 33 displays an observation image of the sample 13 whose brightness and contrast have been adjusted. This makes it possible to obtain an image with no flare and higher resolution than a normal microscope.

Next, the computer 27 proceeds to step # 2.
In step # 1, the current time T0 at the time of executing the various processes in step # 1 is read from the timer 38, and the current time T0 is stored in, for example, the data memory 36.

In this case, in response to an operation input from the operation unit 31, adjustment of brightness and contrast with respect to the two-dimensional image data, and further, such as the start of scanning, amplitude control, and stop of scanning of the resonance type galvanomirrors 22 and 23 are performed. Every time the process is executed, the computer 27 stores the current time T0 in step # 2 and updates the current time T0 to the latest value.

Next, a control method of the resonance type galvanometer 22 will be described with reference to a flowchart of the control method of the resonance type galvanometer shown in FIG.

The computer 27 executes a flowchart (scanner stop processing) of the control method of the resonance type galvanomirror shown in FIG.
Execute repeatedly at regular intervals.

That is, in step # 3, the computer 27 reads the current time T1 from the timer 38 and the time T0 previously stored in the data memory 36.
From the difference between the times T1 and T0, the elapsed time T1-T0 from the end of the processing of the above-described step # 1 executed closest is obtained, and the elapsed time T1-T0 is set to a predetermined time. It is determined whether it is not less than t.

As a result of this determination, if the elapsed time T1-T0 is equal to or longer than the predetermined time t, the computer 27
Moves to step # 4 and issues a command to stop or reduce the amplitude to the drive control unit 25 through the input / output unit 30.

Thus, the resonance type galvanomirror-22
Reduces the amplitude without stopping or completely stopping.

As described above, in the first embodiment, the brightness and contrast of the two-dimensional image data are adjusted by the operation input from the operation unit 31, and further, the scanning of the resonance type galvanomirrors 22 and 23 is started. After processing such as amplitude control and scanning stop, the timer 38
Since the time from the end is observed, if there is no predetermined operation from the operation unit 31 for a predetermined interval or more, the resonance type galvanometer mirror 22 is controlled to stop or reduce its scanning angle. In this case, mechanical stress is reduced, the life can be substantially extended, and the reliability of the microscope is improved. Furthermore, the failure of the resonance type galvanometer mirror 22 is reduced, and the driving power is reduced when the resonance type galvanometer mirror 22 is stopped and the scanning angle is reduced, so that power saving can be achieved.

(2) Next, a second embodiment of the present invention will be described.

The configuration of the scanning laser microscope according to the present invention is the same as that of the scanning laser microscope described in the first embodiment, except for the method of controlling the resonance type galvano mirror 22 and the operation section 31. This is a process for an operation instruction from. A scanning laser microscope according to the present invention will be described below with reference to the configuration diagram shown in FIG.

The program memory 35 stores in advance programs related to various processes such as image processing shown in FIG. 5 and programs related to a control method of the resonance type galvanomirror 22 shown in FIG.

Therefore, the main arithmetic processing unit 28 executes the program stored in the program memory 35 to execute the image processing input from the operation unit 31 and the processing of various settings for the resonance type galvanomirror 22. When it is determined by the timer 38 that there is no operation input from the operation unit 31 for a certain interval or more, an instruction to stop the operation of the resonance type galvanometer mirror 22 or reduce the scan angle is issued to the drive control unit 25 via the input / output unit 30. Is generated and the operation of the resonance type galvanomirror 22 is stopped or the scanning angle is reduced, and if there is an operation input from the operation unit 31, the operation of the resonance type galvanomirror 22 is immediately stopped or the scanning angle is reduced. It has a function of returning to the scanning state of the laser beam 1 with respect to the sample 13 and the state of the process of obtaining an image of the sample 13 before being performed.

Next, a description will be given of a method of controlling the resonance type galvanomirror 22 of the laser scanning microscope configured as described above and various processes such as image processing.

Optical system 21 of laser scanning microscope main body 20
In the above, the laser beam 1 performs XY two-dimensional scanning by the resonance type galvanometer mirror 22 and the galvanometer mirror 23, and the point-like light two-dimensionally scans the sample 13. And the light is received by the photodiode 24.

The computer 27 captures the light receiving signal from the photodiode 24 via the input / output unit 30 by the processing of the main processing unit 28, processes this detection signal, and obtains two-dimensional image data of the sample 13. The two-dimensional image data is stored in the image memory 37, and the output unit 34
Through the monitor device 33 to display an observation image of the sample 13.

Here, the computer 27 repeatedly executes the flowchart (scanner stop processing) of the control method of the resonance type galvanomirror shown in FIG. 6 at regular intervals such as 1 second intervals by the main arithmetic processing unit 28.

That is, in step # 10, the computer 27 reads the current time T1 from the timer 38 and the time T1 previously stored in the data memory 36.
0, and the elapsed time T1-T0 from the end of the nearest executed process is obtained from the difference between the times T1 and T0, and the elapsed time T1-T0 is calculated as a predetermined time t.
It is determined whether or not this is the case.

As a result of this determination, if the elapsed time T1-T0 is equal to or longer than the predetermined time t, the computer 27
Moves to step # 10, adjusts the brightness and contrast of the current two-dimensional image data, further starts the scanning of the resonance type galvanomirrors 22 and 23,
The state of amplitude control, scanning stop, etc.,
To save.

Thereafter, the computer 27 proceeds to step #
In step 4, a command to stop or decrease the amplitude is issued to the drive control unit 25 through the input / output unit 30.

Thus, the resonance type galvanomirror-22
Reduces the amplitude without stopping or completely stopping.

On the other hand, while the observation image of the sample 13 is being displayed, adjustment of the brightness and contrast of the image, the resonance type galvano mirror 22 and the galvano mirror 2 using the operation section 31 are performed.
When operations such as scanning start, amplitude control, and scanning stop are input in step # 11, the computer 27 stops the resonance type galvano mirror 22 in step # 11 of the flowchart relating to various processes such as image processing shown in FIG. It is determined whether the amplitude has decreased.

As a result of this determination, the resonance type galvanomira-2
If computer 2 is stopped or the amplitude is decreasing, computer 2
7 shifts to step # 12, where the resonance type galvanomira-2
2 before stopping or reducing the amplitude, adjusting the brightness and contrast of the current two-dimensional image data stored in the data memory 36 in the above step # 10, further starting the scanning of the resonance type galvanomirrors 22 and 23,
Read the status of amplitude control, scanning stop, etc.

Next, the computer 27 proceeds to step # 1.
3, the state before stopping or reducing the amplitude of the resonance type galvanomirror 22 read from the data memory 36;
That is, a command is issued to each of the drive control units 25 and 26 so as to adjust the brightness and contrast of the two-dimensional image data, and to return to the state such as the start of scanning, the amplitude control, and the stop of scanning of the resonance type galvano mirrors 22 and 23. .

Thereafter, the computer 27 proceeds to step #
In 1, in accordance with an operation instruction input from the operation unit 31, the main arithmetic processing unit 28 adjusts the brightness and contrast of the two-dimensional image data, further starts the scanning of the resonance type galvano mirrors 22 and 23, and controls the amplitude. , The scanning is stopped, and the two-dimensional image data after the image processing at this time is output through the output unit 34 to the monitor device 3.
3

This monitor device 33 displays an observation image of the sample 13 whose brightness and contrast have been adjusted. This makes it possible to obtain an image with no flare and higher resolution than a normal microscope.

Next, the computer 27 proceeds to step # 2
In step # 1, the current time T0 at the time of executing the various processes in step # 1 is read from the timer 38, and the current time T0 is stored in, for example, the data memory 36.

In this case, in response to an operation input from the operation unit 31, adjustment of brightness and contrast with respect to the two-dimensional image data, and further, scanning, amplitude control, scanning stop, etc. of the resonance type galvanometers 22 and 23 are performed. Every time the process is executed, the computer 27 stores the current time T0 in step # 2 and updates the current time T0 to the latest value.

As described above, in the second embodiment, in addition to the first embodiment, the operation of the resonance type galvanometer mirror 22 is stopped or the amplitude (scan angle) is reduced. Upon an operation input from the operation unit 31, the operation of the resonance type galvanometer mirror 22 is immediately stopped or the scanning state of the laser beam 1 on the sample 13 before the amplitude (scanning angle) is reduced and the processing state of obtaining an image of the sample 13 are performed. , The mechanical stress of the resonance type galvanometer mirror 22 is reduced, the life can be substantially extended, and the reliability of the scanning laser microscope can be improved.

Further, when a predetermined operation is instructed from the operation unit 31, control is immediately performed so as to return to the original scanning state, so that the operability is not impaired and the failure of the resonance type galvanometer mirror 22 is reduced. And a resonance type galvanometer mirror 2
2, when the scanning angle is reduced and the scanning angle is reduced, the driving power is small.
Power saving can be achieved.

[0073]

As described above in detail, according to the present invention, even if a resonance type galvanometer mirror is used, the malfunction of the resonance type galvanometer mirror is suppressed without limiting the original function operability, and a highly reliable scanning is performed. Type laser microscope can be provided.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an optical system according to a first embodiment of a scanning laser microscope according to the present invention.

FIG. 2 is a block diagram of the scanning laser microscope.

FIG. 3 is a flowchart relating to various processes such as image processing in the scanning laser microscope.

FIG. 4 is a flowchart of a method of controlling a resonance type galvanomirror in the scanning laser microscope.

FIG. 5 is a flowchart relating to various processes such as image processing in a scanning laser microscope according to a second embodiment of the present invention.

FIG. 6 is a flowchart of a control method for a resonance type galvanomirror in the scanning laser microscope.

FIG. 7 is a configuration diagram of an optical system of a conventional scanning laser microscope.

[Explanation of symbols]

 Reference numeral 20: laser scanning microscope main body, 21: optical system, 22: resonance type galvanometer mirror, 23: galvanometer mirror, 24: photodiode, 25, 26: drive control unit, 27: computer, 28: main arithmetic processing unit, 30 : Input / output unit, 31: operation unit, 32: input unit, 33: monitor unit, 34: output unit, 35: program memory, 36: data memory, 37: image memory, 38: timer.

Claims (2)

[Claims] 1. A laser light output from a laser light source,
In a scanning laser microscope, at least one of which is a resonance type and scans on a sample by two galvanometer mirrors scanning in directions orthogonal to each other, and detecting light from the sample to obtain an image of the sample, at least an image of the sample An operation means for inputting an operation of the processing for the operation, after the end of the processing for the operation input from the operation means, if there is no operation input for a certain interval or more from the operation means, stop the operation of the resonance type galvanometer mirror or A scanning laser microscope, comprising: control means for reducing a scanning angle. 2. The control means stops the operation of the resonance type galvanomirror or immediately stops the operation of the resonance type galvanomirror upon receiving an operation input from the operation means in a state where the operation of the resonance type galvanometer mirror is stopped or the scanning angle is reduced. 2. The scanning laser microscope according to claim 1, wherein the scanning laser microscope has a function of returning to a scanning state of the laser beam on the sample before reducing a scanning angle and a state of processing for obtaining an image of the sample.