JPH0651205A - Scanning microscope - Google Patents

Abstract

PURPOSE:To provide a scanning microscope which is capable of constantly forming a good spot over a wide wavelength range and is easy to handle. CONSTITUTION:Pupil projection lenses for converging illuminating light from a light source 1 onto a surface 13 to be observed are provided by a number corresponding to plural kinds of illuminating rays of light of different wavelengths, and abberations in the wavenlength range corresponding to each pupil projection lens 29a, 29b are corrected, and the lenses are each mounted in a lens switching member 23 provided near an optical path and are selectively disposed on the optical path.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scanning microscope for optically scanning an object with a minute spot, and more particularly to improvement of an optical system for focusing illumination light on a surface to be observed.

[0002]

2. Description of the Related Art An example of the structure of a conventional laser scanning microscope is shown in FIG. The laser scanning microscope shown in the same figure is described in JP-A-61-217014.

In this laser scanning microscope, a laser light source 1
The laser beam emitted from the laser beam passes through the condenser lens 2, the spatial filter 3 and the collimator lens 4 and is incident on the beam expander 5, where it is expanded to a required beam diameter and then incident on the first optical deflector 6. To do.

The direction of travel of the laser beam incident on the first optical deflector 6 is changed, and the laser beam enters the second optical deflector 9 through the pupil transmission lenses 7 and 8. The traveling direction is changed by the second optical deflector, and the pupil projection lens 10, the imaging lens 11,
The light is focused on a sample 13 through the objective lens 12.

By arranging the first and second optical deflectors 6 and 9 at positions conjugate with the pupil position of the objective lens 12, the laser beams are orthogonalized to each other by X, When each is deflected in the Y direction, the beam spot moves the sample 13 in the XY direction with the optical axis kept constant.
It becomes a one-dimensional scanning. In the optical system shown in FIG. 10, when the pupil projection lens 10 has an aberration, a spot is not properly formed on the observation sample due to the influence of the aberration. Therefore, conventionally, a pupil projection lens using a glass material that can most effectively remove aberration in the wavelength range of the laser light oscillated by the laser light source 1 is used.

By the way, in the case of illuminating a sample with a plurality of types of laser light having a multi-wavelength oscillation and having different wavelength ranges, or different wavelength ranges such as B excitation, G excitation and ultraviolet light excitation. Fluorescence observation may be performed using excitation light. For example, B excitation, G in fluorescence observation
In the case of excitation, the wavelength range is 450 to 650 nm, and in the case of ultraviolet light excitation, the wavelength range is 300 to 500 nm. In such a case, it is necessary to correct the aberration of the pupil projection lens over the entire wavelength range.

[0007]

However, the glass material used for the pupil projection lens has a limited wavelength range in which aberration can be corrected depending on its type. For example, the visible light range is 488 to 630 nm, and the ultraviolet light range is 300 to 500 nm. Therefore, there is currently no glass material capable of excellent aberration correction in a wide range of 300 to 650 nm as in the above fluorescence observation. Therefore, the pupil projection lens suitable for the wavelength range of 488 to 630 nm cannot be used in the case of ultraviolet light excitation which is the wavelength range of 300 to 500 nm.

Further, since the pupil projection lens has a remarkably reduced transmittance for ultraviolet light, the types of glass materials that can be used are limited. It is extremely difficult to combine such limited glass materials to create a pupil projection lens having a wider wavelength range.

The present invention has been made in view of the above circumstances, and it is possible to always form a good spot on the surface to be observed over a wide wavelength range including an ultraviolet light range to a visible light range. Moreover, it is an object of the present invention to provide a scanning microscope that is easy to operate.

[0010]

According to a first aspect of the present invention, there is provided a scanning microscope including a pupil projection lens for converging illumination light from a light source on a surface to be observed. , Provided in a number corresponding to a plurality of types of the illumination light having different wavelength ranges from each other, are subjected to aberration correction in the corresponding wavelength range, and are selectively loaded by being respectively mounted in lens switching members provided in the vicinity of the optical path. It is characterized in that it is arranged on the optical path.

According to a second aspect of the present invention, in the scanning microscope, the pupil projection lenses and the imaging lenses are provided in the numbers corresponding to a plurality of types of illumination light having different wavelength ranges, and the pupil projection lenses and the coupling lenses are provided. Aberration correction in a wavelength range corresponding to the image lens is performed, and further, the pupil projection lens and the imaging lens are respectively mounted on respective lens switching members provided near the optical path and selectively arranged on the optical path. Is characterized by.

According to a third aspect of the scanning microscope of the present invention, a pupil transmission lens, a pupil projection lens, and an imaging lens are provided in a number corresponding to a plurality of types of illumination light having different wavelength ranges from each other. Aberration correction in the wavelength range corresponding to the transmission lens, the pupil projection lens, and the imaging lens is performed.
It is characterized in that the pupil transmission lens, the pupil projection lens and the image forming lens are respectively mounted on respective lens switching members provided in the vicinity of the optical path and selectively arranged on the optical path.

[0013]

In the scanning microscope of the present invention, the plurality of pupil projection lenses, the imaging lenses, and the pupil transmission lenses, each of which has been subjected to aberration correction corresponding to a plurality of types of illumination light having different wavelength ranges, serve as lens switching members. Each is loaded and placed near the optical path. Then, according to the wavelength range of the illumination light used, a pupil projection lens, an imaging lens, and a pupil transmission lens whose aberrations have been corrected for the wavelength range are selected and arranged on the optical path by a lens switching member.

[0014]

Embodiments will be described below with reference to the drawings.

FIG. 1 shows the configuration of the main part of a scanning microscope according to an embodiment of the present invention. The configuration of the entire optical system of the present embodiment is the same as that shown in FIG. 10, and the different part is the configuration of the pupil projection lens part. Therefore, only the configuration of the pupil projection lens portion is shown in detail in FIG.

In this embodiment, a turret mechanism 23 as a lens switching member is provided between the end of the optical path of the scan unit 21 on the microscope side and the end of the optical path of the microscope 22 on the scan unit side. .

The scan unit 21 is shown in FIG.
For deflecting the illumination light in the X and Y directions at
Which is a part of the optical system including the second optical deflectors 6, 9 and the like,
The microscope 22 is a part of an optical system including an imaging lens 11, an objective lens 12, and the like.

In the turret mechanism 23, the outer frame 24 having the turret storage space inside has the scan unit 2
It is fixed between 1 and the microscope 22. This outer frame 24
A turret 25 is stored in the turret storage space inside.

A shaft 26 is fitted and inserted in the center of the turret 25 with bearings 27 arranged around the shaft 26, and both ends of the shaft 26 are fixed to the outer frame 24, respectively.
The shaft 26 is arranged parallel to the optical axis, and is arranged at a position separated from the optical axis by a predetermined distance, and rotatably supports the turret 25.

Inside the turret 25, first and second cases 28a and 28b are detachably provided. The first case 28a is provided with an ultraviolet pupil projection lens 29a composed of a plurality of lenses, and the second case 28b.
Is provided with a visible pupil projection lens 29b including a plurality of lenses.

For example, the pupil projection lens 29a provided in the first case 28a has optical characteristics capable of aberration correction for light in the visible light range of 450 nm to 700 nm, and the pupil projection lens 29a is provided in the second case 28b. Pupil projection lens 29 provided
b has optical characteristics capable of aberration correction for light in the ultraviolet light region of 300 nm to 500 nm.

3A and 3B show the optical characteristics of the pupil projection lens 29b. In the figure (a),
The spherical aberration of the pupil projection lens 29b with respect to ultraviolet light is shown, and the distortion aberration of the pupil projection lens 29b with respect to ultraviolet light is shown in FIG.

3 (c) and 3 (d) show the optical characteristics of the pupil projection lens 29a. In FIG. 7C, the spherical aberration of the pupil projection lens 29a for visible light is
Further, FIG. 7D shows distortion aberration with respect to visible light. Although a plurality of characteristic curves are shown in FIGS. 3 (a) and 3 (c), aberrations for ultraviolet light having different wavelengths are shown.

A positioning click mechanism 31 is provided between the upper surface of the turret 25 loaded with the pupil projection lenses 29a and 29b and the outer frame 24, and the pupil projection lenses 29a and 29b are placed on the optical axis. It can be positioned at.

The turret 25 has an empty space in which no pupil projection lens is inserted, and the space is used to scan the scan unit 21 and the microscope 2.
It is possible to align the optical system with the optical system 2.

FIG. 2 shows the configuration of the optical system over the entire apparatus when observation is performed using ultraviolet light. Since the objective lens 12 needs to be replaced according to the wavelength used, as with the pupil projection lens, the ultraviolet light objective lens 12a and the visible light objective lens 12b are attached to the revolver 14.

The turret mechanism 2 configured as described above
In the present embodiment including No. 3, when performing observation using visible light, the turret 25 is rotated to arrange the pupil projection lens 29a fixed to the first case 28a on the optical axis, and further the revolver. 14 is rotated and the visible light objective lens 12b is arranged on the optical axis.

From the scan unit 21 to the pupil projection lens 2
When the illumination light is incident on 9a, the visible light is reflected by the pupil projection lens 29.
Since the aberration is corrected to the state shown in FIGS. 3C and 3D by a, the generation of the aberration by the pupil projection lens 29a is suppressed, and a good spot is formed on the surface of the observation sample.

When the observation is carried out using ultraviolet light,
The pupil projection lens 29b fixed to the second case 28b is arranged on the optical axis, and the ultraviolet light objective lens 12a is arranged on the optical axis. This operation is performed by the turret 25 and the revolver 14.
All you have to do is rotate it.

When the turret 25 is rotated, the pupil projection lens 29a fixed to the first case 28a moves away from the optical axis, and instead the pupil projection lens 29b fixed to the second case 28b moves to the optical axis. approach. When the pupil projection lens 29b approaches the optical axis, the positioning click mechanism 31 fixes the pupil projection lens 29b on the optical axis.

When ultraviolet light enters the pupil projection lens 29b from the scan unit 21, the ultraviolet light is aberration-corrected by the pupil projection lens 29b to the state shown in FIGS. 3 (a) and 3 (b). However, the generation of aberration is suppressed, and a good spot is formed on the surface of the observation sample as described above.

Therefore, according to the present embodiment, the pupil projection lenses 29a and 29b having different optical characteristics are provided in the turret mechanism 23, and the pupil projection lens having appropriate optical characteristics according to the wavelength range of the illumination light used is provided. Since it can be arranged on the optical axis, a single unit can always form a good spot over a wide wavelength range from the ultraviolet light range to the visible light range. Moreover, since the turret mechanism 23 is used to switch between the pupil projection lenses 29a and 29b, the operation is extremely easy.

As described above, a good spot in each wavelength range is irradiated onto the sample by the objective lens 12 in FIG. As a matter of course, as the objective lens 12, an objective lens whose aberration is corrected in the same wavelength range as each projection lens is prepared. Therefore, when the illumination light becomes ultraviolet light, the pupil projection lens 29a is installed on the optical axis by the turret 25,
An ultraviolet objective lens is selected.

In the above embodiment, the turret mechanism 2 is used to switch between the pupil projection lenses 29a and 29b having different optical characteristics.
Although the case of using 3 has been described, the slider mechanism 30 shown in FIGS. 4 and 5 can also realize the same function as the turret mechanism 23.

The slider mechanism 30 includes a slider 3
1 and a rail 32 for linearly moving the slider 31
Consists of. The slider 31 has a fitting projection 31a formed on the rail-side surface in the direction of linear movement. Further, the slider 31 is formed with through holes 33a to 33c having a predetermined diameter penetrating between the side surfaces, and each of the through holes 33a to 33c has a diameter slightly smaller than that of the through holes 33a to 33c. The first and second cases 35 and 36 are inserted. For example, a pupil projection lens 37 for visible light is fixed to the first case 35, and a pupil projection lens 38 for ultraviolet light is fixed to the second case 36.

On the side surface of the slider 31, screw holes 34a to 34c are provided corresponding to the through holes 33a to 33c. By inserting a fixing screw into each of the screw holes 34a to 34c, the corresponding through hole 33a is formed.
The cases inserted in the ~ 33c are fixed.

Further, the rail 32 is arranged at a position separated from the optical axis by a predetermined distance, with its longitudinal direction orthogonal to the optical axis. On the slider side surface of the rail 32, a dovetail groove 32a into which the fitting convex portion 31a provided on the slider 31 is slidably fitted is formed. A screw hole 40 is formed on the side surface of the rail 32, and the slider 31 is fixed by inserting a screw into the screw hole 40.

When the slider 31 is moved to arrange the through holes 33a (33b, 33c) on the optical path, the center of the through holes 33a (33b, 33c) (center of the pupil projection lens) coincides with the optical axis. Is adjusted.

Further, the three through holes 33a, 33b, 3
A positioning mechanism (not shown) is provided to position the slider 31 at the position of any of the through holes 3c when it comes to the optical axis.

The slider mechanism 3 configured as described above
0, the pupil projection lenses 37 and 38 having different optical characteristics
Can be selectively arranged on the optical path according to the wavelength range of the illumination light, and the same effect as that of the above-described embodiment can be obtained.

Moreover, the slider mechanism 3 shown in FIGS.
Since 0 has three through holes 33a, 33b, 33c, a pupil projection lens for not only visible light and ultraviolet light but also infrared light can be attached, and a single unit can be used. It is possible to handle three types of illumination light.

The turret mechanism 23 and the slider mechanism 30 have two or three pupil projection lenses.
The type is not limited, and four or more types of pupil projection lenses can be provided. Next, a second embodiment of the present invention will be described.

FIG. 6 shows a schematic structure of the optical system of the scanning microscope according to the second embodiment. In the figure, parts having the same functions as those of the apparatus shown in FIGS. 1 and 10 are given the same reference numerals.

The scanning microscope of the present embodiment is configured so that the imaging lens and the pupil transmission lens in addition to the pupil projection lens can be switched according to the wavelength range to be used. The turret mechanism 40 for the imaging lens is provided between the turret mechanism 23 for the pupil projection lens and the objective revolver 14.

The turret mechanism 40 has a rotation axis parallel to the optical axis at a position separated from the optical axis by a predetermined distance, and is attachable / detachable in a state where the first and second cases 41a and 41b are parallel to the optical axis. It is provided in. In the first case 41a,
An ultraviolet imaging lens 42a is provided, and a visible imaging lens 42b is provided in the second case 41b.

Further, a turret mechanism 43 for the pupil transmission lens
Are provided between the first optical deflector 6 and the second optical deflector 9. The turret mechanism 43 has a rotation axis parallel to the optical axis at a position separated from the optical axis by a predetermined distance.
The cases 44a and 44b are detachably provided in parallel with the optical axis. The first case 44a is provided with ultraviolet pupil transmission lenses 45 and 46, and the second case 44b is provided with visible pupil transmission lenses 47 and 48.

The turret mechanisms 40 and 43 are provided with a click mechanism (not shown) similar to the turret mechanism 23 for pupil projection described above so that each lens can be positioned on the optical axis. . In addition, an empty space in which no lens is inserted is secured in the turret mechanism, and the space can be used to adjust the alignment of the optical system.

In the present embodiment configured as described above, when the observation is performed using ultraviolet light, the turret mechanism 2 is used.
3, 40 and 43 are respectively operated so that the ultraviolet pupil projection lens 29a, the imaging lens 42a, the pupil transmission lens 45,
46 is arranged on the optical axis. In accordance with this, the objective lens 12a for ultraviolet light is also arranged on the optical axis by operating the revolver 14.

In the optical system in which the respective optical elements are arranged as described above (state shown in FIG. 6), aberration correction is performed not only in the pupil projection lens 29a but also in the imaging lens 42a and the pupil transmission lenses 45 and 46. Therefore, the occurrence of aberration is suppressed, and a good spot is formed on the surface of the observation sample.

When observing with visible light,
The turret mechanisms 23, 40, and 43 are operated to operate the pupil projection lens 29b for visible light and the imaging lens 42.
b, the pupil transmission lenses 47 and 48 are arranged on the optical axis, and the objective lens 12b for visible light is arranged on the optical axis.

In the optical system in which the respective optical elements are arranged as described above, since the occurrence of aberration with respect to visible light is suppressed,
In observation using visible light, a good spot is formed on the surface of the observation sample.

As described above, according to the present embodiment, not only the pupil projection lens but also the imaging lens and the pupil transmission lens perform good aberration correction for visible light and ultraviolet light. The occurrence of aberration can be suppressed more efficiently, and as a result, an extremely good observation image can be obtained over a wide wavelength range.

By the way, in the above-mentioned first and second embodiments, an example in which the pupil transmission lens is arranged between the first optical deflector 6 and the second optical deflector 9 has been described. When the deflector 6 and the second optical deflector 9 are close to each other, the pupil transmission lens can be eliminated. An example in which the pupil transmission lens is deleted is shown in FIG.

In the optical system shown in FIG. 7, the midpoint M of the first optical deflector 6 and the second optical deflector 9 on the optical axis is the objective lens 12.
Projected on the pupil of. When the distance between the midpoint M and each of the light deflectors 6 and 9 is short, almost the surface of each of the light deflectors 6 and 9 is projected onto the pupil of the objective lens 12.

As described above, when the pupil transmission lens is not particularly required, there is an advantage that the loss of the light amount is small and the configuration is simple and the cost can be reduced by removing the pupil transmission lens. Next, a third embodiment of the present invention will be described with reference to FIG.

The present embodiment is an example in which a pupil projection lens and an imaging lens having the same wavelength range for aberration correction are housed in the same case and switched at once. In FIG. 8, the same parts as those in the first and second embodiments described above are designated by the same reference numerals.

The scanning microscope of this embodiment is provided with a shared turret mechanism 50 for the pupil projection lens and the imaging lens between the second optical deflector 9 and the revolver 14.
The shared turret mechanism 50 has a rotation axis parallel to the optical axis at a position separated from the optical axis by a predetermined distance, and is detachably provided in a state where the first and second cases 51a and 51b are parallel to the optical axis. Has been.

The first case 51a is provided with an ultraviolet pupil projection lens 52a and an ultraviolet imaging lens 53a. The second case 51b is provided with a visible light pupil projection lens 52b and a visible light imaging lens 53b. Other configurations are similar to those of the second embodiment described above.

In the present embodiment configured as described above, by operating the shared turret mechanism 50, the pupil projection lens and the imaging lens can be switched at the same time by one operation, so that the operability is good. Further, the structure can be simplified and the cost can be reduced as compared with the case where the turret mechanism is provided in each of the pupil projection lens and the imaging lens. Next, a fourth embodiment of the present invention will be described with reference to FIG.

The present embodiment is an example in which the operation of each turret mechanism and revolver is electrically controlled by using a motor in the configuration of the above-mentioned second embodiment. In the figure, the same parts as those in the second embodiment are designated by the same reference numerals.

In the scanning microscope of this embodiment, the turret mechanism 23 for the pupil projection lens is driven by the motor 61, the turret mechanism 40 for the imaging lens is driven by the motor 62, and the turret mechanism for the pupil transmission lens is further used. 43 to motor 63
I am trying to drive with. Further, the revolver 14 is driven by the motor 64. And each motor 61-
The operation of 64 is controlled by the controller 65. The controller 65 uses the revolver 1 as in the second embodiment.
4, a program for driving and controlling the turret mechanisms 23, 40, 43 is stored.

According to the present embodiment thus constructed, the revolver 14 and the turret mechanisms 23, 40, 43 are electrically controlled collectively by the controller 65, so that the turret mechanism or the like can be manually operated. In comparison, the operability can be improved. The present invention is not limited to the above-described embodiments, but can be modified and implemented without departing from the scope of the present invention.

[0063]

As described above in detail, according to the present invention, it is possible to always form a good spot on the surface to be observed over a wide wavelength range including the ultraviolet light range to the visible light range, and to perform the operation. It is possible to provide an easy-to-use scanning microscope.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a main part of a scanning microscope according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of an optical system of the scanning microscope according to the first embodiment.

FIG. 3 is a diagram showing optical characteristics of a pupil projection lens provided in the scanning microscope according to the first embodiment.

FIG. 4 is a perspective view of a slider mechanism included in a scanning microscope according to a modification of the first embodiment.

5 is a sectional view of the slider mechanism shown in FIG.

FIG. 6 is a configuration diagram of an optical system of a scanning microscope according to a second embodiment of the present invention.

FIG. 7 is a configuration diagram of an optical system of a scanning microscope according to a modification of the second embodiment.

FIG. 8 is a configuration diagram of an optical system of a scanning microscope according to a third embodiment of the present invention.

FIG. 9 is a configuration diagram of an optical system of a scanning microscope according to a fourth embodiment of the present invention.

FIG. 10 is a block diagram of an optical system of a conventional scanning microscope.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Laser light source, 6 ... 1st deflector, 9 ... 2nd deflector, 10, 29a, 29b, 37, 38 ... Pupil projection lens, 11 ... Imaging lens, 12 ... Objective lens, 13 ... Observation sample , 21 ... Scan unit, 22 ... Microscope, 23,
40, 43 ... Turret mechanism, 28a ... UV pupil projection lens, 28b ... Visible light pupil projection lens, 42a ... UV imaging lens, 42b ... Visible light imaging lens, 45, 46
... UV pupil transmission lens, 47, 48 ... Visible light pupil transmission lens.

Claims (3)

[Claims] 1. A scanning microscope equipped with a pupil projection lens for converging illumination light from a light source on a surface to be observed, the pupil projection lens corresponding to a plurality of types of illumination light having different wavelength ranges from each other. A scanning microscope, which is characterized in that a plurality of lenses are provided, aberrations are corrected in the corresponding wavelength regions, and the lens switching members provided in the vicinity of the optical path are respectively loaded and selectively placed on the optical path. 2. A scanning microscope equipped with a pupil projection lens and an imaging lens for converging illumination light from a light source on an observed surface, wherein the pupil projection lens and the imaging lens have different wavelength ranges from each other. A number corresponding to a plurality of types of illumination light is provided, aberrations in the corresponding wavelength ranges are corrected, and each lens switching member provided near the optical path is loaded and selectively placed on the optical path. A scanning microscope characterized in that 3. Illumination light from a light source is incident on a first light deflector, and illumination light deflected by the first light deflector is incident on a second light deflector through a pupil transmission lens, In a scanning microscope that collects illumination light deflected by a two-light deflector on a surface to be observed through a pupil projection lens, an imaging lens, and an objective lens, the pupil transmission lens, the pupil projection lens, and the imaging lens are: A plurality of types of illumination light having different wavelength regions are provided, aberration correction is performed for the corresponding wavelength regions, and each lens switching member provided in the vicinity of the optical path is individually loaded to selectively emit light. A scanning microscope characterized by being placed on the road.