JPH1020099A - Scanning confocal x-ray microscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a microscope by which clear high-resolution observation of the sample of an organism can be enabled. SOLUTION: A scanning confocal X-ray microscope is provided with at least a X-ray source 21, a X-ray objective optical system 34 for radiating the X-rays emitted from the X-ray source 21 on a sample 4 that is held by a sample holder 23, the sample holder 23 for holding the sample 4, a scanning driving system 32 for scanning the sample holder 23, and a X-ray detecting system 31 for detecting the X-rays emitted from the sample 4. In this case, the X-ray source 21 is made to be a point light source, and also a X-ray converging optical system 35 for converging the X-rays emitted from the sample 4 and a pin hole 6 or slit are provided between the sample holder 23 and the X-ray detecting system 31 to form a confocal optical system.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scanning X-ray microscope using a confocal optical system.

[0002]

2. Description of the Related Art In recent years, in the fields of medicine and biotechnology, which are progressing rapidly, ordinary visible light (wavelength λ = about 400 nm to 800 nm) is used.
m) and higher resolution than light microscopy using live samples (eg, cells, bacteria, sperm, chromosomes,
There is an increasing demand for a high-resolution microscope capable of clearly observing even mitochondria, flagella and the like (hereinafter referred to as biological samples).

There is an electron microscope as a microscope having much higher resolution than the optical microscope. However, in an electron microscope, since the electron optical system is placed in a vacuum, the sample or the sample container that stores the sample also needs to be placed in a vacuum.
When a sample is placed directly in a vacuum, it is naturally impossible to place the sample in a living state. When a living sample is placed in a sample container and placed in a vacuum, an electron beam is used. A living sample cannot be observed because there is no window material of the sample container that sufficiently transmits the sample.

In order to enable high-resolution observation of biological samples, confocal scanning microscopes and X-ray microscopes using X-rays having a wavelength of λ = 2 to 5 nm instead of visible light have been studied.
It is being specifically developed. The optical system of the confocal microscope was proposed by M. Minsky in 1957, and is one of scanning optical systems in which a pinhole is added to a light source and a detector. In recent years, in the field of optical microscopes, laser confocal microscopes using a laser as a light source have been developed. These lasers have the characteristics of higher resolution and higher image quality than ordinary optical microscopes, It is also used for observation.

FIG. 4 shows an outline of the confocal optical system, and FIG. 5 briefly shows the relationship of the imaging performance. The optical characteristics of such an arrangement have already been examined from various angles, and a representative work summarizing these optical characteristics includes Tony
Theory and Pract by Wilson and Colin Sheppard
There is ice of Scanning Optical Microscopy. The confocal optical system includes a light source 1 and a pinhole 2 as shown in FIG.
, Objective optical system 3, sample 4, focusing optics 5, pinhole 6
, And a detector 7.

When an image of a sample is obtained by scanning, there are two methods of scanning by moving the sample and scanning by moving the beam. When scanning a sample, a scanning drive stage for scanning a sample holder that holds the sample is provided, and when scanning a spot light, a scanning optical system for spot light is provided. Further, a laser confocal microscope that has been frequently used in recent years replaces the light source 1 and the pinhole 2 in FIG. 4A with a laser beam 8 which is a parallel beam as shown in FIG. a) The converging optical system 3 is the same optical system as the objective optical system 3 of FIG. 3A, and a pinhole 6 is arranged at a position conjugate with the parallel light of the laser, and a detector that detects light passing through the pinhole 6 7 is provided to detect the reflected light of the sample, and is usually provided with a beam scanning optical system 10 additionally.

The basic imaging performance such as the resolution of such a laser confocal microscope is almost the same as that of the basic type shown in FIG. 4A, and the behavior is slightly different from that of the vertical type. FIG. 5 shows the characteristics of the imaging performance of the confocal optical system shown in FIG.
Shown in Pinhole 2 illuminated by light source 1 in FIG.
Works as a point light source when the pinhole 2 is sufficiently small. The image of this point light source is converted into a sample 4 by the objective optical system 3.
Projected onto it to form a spotlight.

At this time, when the objective optical system 3 has no aberration, this spot becomes a diffraction-limited image determined by the wavelength to be used and the numerical aperture as shown in FIG. The spot light is subjected to intensity modulation depending on the transmittance of the sample 4 and is projected onto the pinhole 6 by the focusing optical system 5.
Thus, only the light that has passed through the pinhole 6 is detected by the detector 7. Here, the detector 7 is looking at the sample surface through the pinhole.

The pinhole 6 is sufficiently small, and the condensing optical system 5
Has no aberration, only the diffraction-limited region determined by the wavelength used and the numerical aperture can be seen on the sample surface. When the same optical system is used for the objective optical system and the condensing optical system, the characteristic is such that the intensity distribution of the spot light of the objective optical system directly becomes the detection rate. Therefore, in the confocal optical system, the spot light projected by the objective optical system 3 is observed through the condensing optical system 5 and further through the pinhole 6, and the point image distribution representing the effective optical performance is obtained. The function is represented by the product of the point spread function of the objective optical system 3 and the point spread function of the condensing optical system 5, and actually has optical performance as shown in FIG.

As is apparent from FIG. 5, in the confocal optical system, the peak is slightly narrowed and the peripheral light is reduced as compared with the ordinary spot light scanning. This improves resolution and
It means that the contrast is improved. Further, since the influence of stray light and the like is reduced by passing through the pinhole, a clear image with better contrast can be obtained by using a confocal optical system as compared with a normal microscope image without using the confocal optical system.

Although an example using a pinhole has been described here, if a slit is used, a similar effect can be obtained in a one-dimensional direction, and a confocal optical system actually using a slit is also used. I have. Further, as shown in FIGS. 5 (c) and 5 (d), when an infinitely narrow annular zone is used for the aperture, the shape of the peak is further narrowed, and the image of the normal annular aperture described later is formed. , Ambient light is suppressed.

However, the resolution of a confocal microscope using a confocal optical system is limited by the numerical aperture (NA) of an objective lens and the wavelength of light, as in a normal microscope, and the resolution is also the resolution of an optical microscope. This is about one half of that, and there is no remarkable improvement in the sense of improving the resolution. On the other hand, an X-ray microscope having a shorter wavelength than light has been studied in order to overcome the resolution limitation due to the wavelength of light. Since an X-ray microscope uses X-rays having a wavelength of about 1 to 10 nm, which is about 1/100 of the wavelength of light, a much higher resolution than an ordinary microscope is expected.

The absorption of an X-ray by a substance changes as shown in FIG. 6 depending on the wavelength of the X-ray, the atomic number of the substance, and the like. In general, the longer the wavelength of X-rays is for the same substance, the easier the substance is to absorb the X-rays. In particular, in the X-ray wavelength range of 23 to 44 °, water having an oxygen atom has a higher X-ray transmittance (lower X-ray absorption) than an organic substance having a carbon atom such as a protein. That is, when observed using X-rays, a contrast is obtained from the difference in the X-ray absorptivity between water and protein, so that the structure of the cells in water can be distinguished without staining.

This wavelength region is called a water window, and this region is an X-ray wavelength region that is very useful for living body observation. Thus, the X-ray microscope provides an X
If a line is used, organisms also have features such as high resolution and no staining. FIG. 7 shows an example of a simple structure and an optical system of an imaging X-ray microscope among such X-ray microscopes.

In FIG. 7, an X-ray emitted from an X-ray generator 21 is condensed by an X-ray illumination optical system 22 and is sampled by a sample container 23.
Illuminates the sample 4 stored inside. Then, the X-ray transmitted through the sample 4 is formed on the X-ray imaging device 25 by the X-ray magnifying optical system 24 as a sample image. The optical path length from the X-ray generator 21 to the X-ray imaging device 25 is, for example, about 2 m. Also,
Each optical system is arranged in a lens barrel vacuum container 26 evacuated by an exhaust device 27 in order to prevent absorption of X-rays.

Further, in addition to the imaging X-ray microscope as shown in FIG. 7, a scanning X-ray microscope as shown in FIG. 8 has been proposed, and its development is progressing. In this scanning X-ray microscope, the X-ray emitted from the X-ray generator 21 is reduced by the X-ray objective optical system 30,
An X-ray micro-beam is formed by condensing the beam, and the beam is converged on the sample 4 stored in the sample container 23. Then, the intensity of the X-ray transmitted through the sample 4 is detected by the X-ray detector 31.

Here, the sample container 23 containing the sample 4 is mounted on a scanning drive stage 32, and the drive of the stage is controlled by a control device 33. Further, the control device forms an image from the signal of the X-ray detector 31 and displays the image on the monitor screen 28. Incidentally, as an image forming optical system of the X-ray microscope, an optical system using an oblique incidence reflection type X-ray mirror using total reflection as shown in FIG. FIG. 9C illustrates an optical system using a multilayer mirror.
The Fresnel zone plate optical system shown in FIG.

In the oblique incidence mirror shown in FIG. 9A, an optical system called a Wolter type, in which a hyperboloid of revolution and a spheroid are combined as shown in the figure, is often used. Since this optical system utilizes total reflection, there is an advantage that the light use efficiency is high and the light is bright. In the multilayer mirror of FIG. 9B, an optical system called a Schwarzschild type combining two concentric spherical mirrors as shown in the figure is often used. This optical system has an advantage that aberration is corrected relatively well and good imaging performance is exhibited.

However, the multilayer mirror does not have a multilayer film that works effectively in a wavelength range called the water window, and it is difficult to use an X-ray microscope in this wavelength range in terms of efficiency. The resolution of the zone plate shown in FIG. 9C is determined by the line width of the outermost periphery, so that there is an advantage that the resolution can be improved with the improvement of the fine processing technology. However, since the zone plate utilizes diffraction of X-rays, the use efficiency of X-rays is limited to about 20% even if the most efficient phase zone plate is used.

The resolution of the X-ray optical system used in such an X-ray microscope is theoretically the wavelength to be used and the aperture angle (N.
A.). According to Abbe's imaging theory, if the wavelength used is λ, the resolution R is R
= 0.61 · λ / NA. As expressed by the above equation, the smaller the wavelength λ used, the better the resolution, but
This indicates that when the NA is small, the resolution deteriorates.

Therefore, although the X-ray microscope uses a shorter wavelength of 1/100 or less than the microscope using ordinary visible light, the NA is about 1/10 of that of the ordinary visible light microscope. Because only the optical system can be assembled, the resolution is
It is only about 1/10. FIG. 9 shows the shape of a typical aperture taken by each X-ray optical system and the shielding factor. Further, an X-ray optical system used in such an X-ray microscope includes:
In general, many have a ring-shaped opening. In the orifice of the orifice, the resolution generally improves as the width of the orbicular zone decreases, but the contrast deteriorates. This situation is shown in FIG.
Shown in

In FIG. 10, (a) is a circular opening, and (b) is a circular opening.
The orbicular zone opening of 1/2 and (c) show the characteristics of the infinitely narrow orbicular opening, respectively.As is clear from the figure, the peak narrows and the resolution improves as the orbicular zone becomes narrower.
As ambient light increases, the contrast deteriorates. In particular, in a grazing incidence optical system such as a rotationally symmetric Wolter, an annular zone is narrowed, so that only an image with low contrast can be obtained. Therefore, when imaging a sample having a fine structure with low contrast such as a living body even if the resolution is high, there is a problem that a sample having a small resolution or the like cannot be actually seen well.

Since X-rays have a short wavelength, the light (photon) energy is at least one order of magnitude greater than that of visible light. In other words, X-ray microscopes have excellent characteristics such as high resolution and no staining of living organisms by using X-rays in a short wavelength region called a water window region, but high-energy X-rays are applied to biological samples. Since irradiation and observation are performed, there is a problem that a biological sample is easily damaged.

Further, the current X-ray microscope has a problem that there is no X-ray source having a large output on a laboratory scale. X
Examples of the radiation source include a radiation light, a laser plasma X-ray source, and an X-ray tube excited by an electron beam. Even a small radiation light has a size of several meters and is an extremely expensive device. Not easily handled in the laboratory.

The laser plasma X-ray source is also very powerful, but in order to make it a powerful X-ray source, it is necessary to use a very high-power laser for excitation, which is also several meters in size. The size is very expensive. For this reason, X-ray sources that can be used on a laboratory scale are limited to small-scale laser plasma X-ray sources that do not have a very high X-ray intensity or X-ray tubes excited by an electron beam.

Therefore, in the X-ray microscope, in order to reduce damage to a biological sample by using an X-ray source that can be used on a laboratory scale and to effectively use a relatively low-intensity X-ray source, It is preferable to use a grazing incidence optical system which is a highly efficient X-ray optical system. However,
As described above, since the high-efficiency oblique incidence optical system has a narrow annular aperture, there is a problem that only an image with low contrast can be obtained.

[0027]

As described above, various attempts have been made to improve the performance of microscopes for enabling clear, high-resolution observation of biological specimens. However, even confocal microscopes and X-ray microscopes have been devised. It is said that it is not possible to obtain a sufficient resolution improvement, and furthermore, it is difficult to observe fine structures such as low-contrast organisms, especially with an X-ray microscope using a grazing incidence mirror, which can only obtain low-contrast images. There is a problem.

The present invention has been made in view of such a problem, and an object of the present invention is to provide a microscope capable of observing a biological sample with clear and high resolution.

[0029]

Accordingly, the present invention firstly provides an "X-ray source, an X-ray objective optical system for irradiating X-rays from the X-ray source onto a sample held in a sample holder, In a scanning X-ray microscope equipped with a sample holder that holds a, a scanning drive system that scans the sample holder, and an X-ray detection system that detects X-rays from the sample, the X-ray source is a point light source, and An X-ray focusing optical system for collecting X-rays from the sample and a confocal optical system formed by providing a pinhole or a slit between the sample holder and the X-ray detection system. A scanning confocal X-ray microscope (Claim 1).

The present invention also provides a second aspect, wherein the X-ray source as the point light source is a laser plasma X-ray source or an X-ray source obtained by combining a pinhole with an X-ray non-point light source. A scanning confocal X-ray microscope according to claim 1 (claim 2) "is provided. The third aspect of the present invention is a scanning confocal X-ray microscope according to claim 1 or 2, wherein a grazing incidence reflecting mirror is used for the X-ray focusing optical system. provide.

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION According to the present invention, at least X
A scanning X-ray microscope equipped with a radiation source, an X-ray objective optical system, a sample holder, a scanning drive system for scanning the sample holder, and an X-ray detection system uses the X-ray source as a point light source, and An X-ray focusing optical system for collecting X-rays from the sample and a confocal optical system by providing a pinhole or a slit between the X-ray detection system to form a scanning confocal X-ray microscope. Therefore, clear high-resolution observation of the biological sample is possible.

The reason why the scanning confocal X-ray microscope according to the present invention overcomes the above-mentioned problems of the conventional confocal microscope and X-ray microscope and enables clear high-resolution observation of a biological sample will be described below. Will be described. For example, as shown in FIG.
In the scanning X-ray microscope, the X-ray source is a point light source (for example, the size of the light emitting point of the laser plasma X-ray source 21 is reduced to a point that can be regarded as a point), and a sample container containing the biological sample 4 ( An X-ray focusing optical system 35 between the sample holder 23 and an X-ray detector (an example of an X-ray detection system) 31;
By providing the pinhole 6 or the slit, a confocal optical system in the X-ray region is formed.

As described above, when a confocal optical system is used,
The effective point spread function related to imaging is the point spread function of the X-ray objective optical system that forms a microbeam on the sample, and the X-ray transmitted through the sample is collected and placed on the detector surface. It is represented by the product of the point spread function of the X-ray focusing optical system to be projected.
Incidentally, the scanning confocal X-ray microscope of FIG. 1 uses a Wolter type oblique incidence optical system as the condensing optical system 35. As described above, since the imaging characteristic of a grazing incidence optical system such as the Wolter type generally has a thin annular aperture, the spot shape becomes a diffraction pattern of the annular aperture.

As shown in FIG. 10, the feature of the diffraction pattern of the annular aperture is that the spot diameter at the center becomes slightly smaller and the resolution is improved as compared with the diffraction pattern of the circular aperture, but the diffraction pattern around the center spot is improved. The light intensity increases and the contrast decreases. Such imaging performance is very problematic when capturing images of living things with low contrast.

However, as in the case of the scanning confocal X-ray microscope according to the present invention, when the oblique incidence optical system is used for the converging optical system 35 (constituting a confocal optical system), the objective The image forming characteristics are obtained by multiplying the diffraction pattern of the optical system 34 with the diffraction pattern of the annular opening. Therefore, if the objective optical system and the condensing optical system (oblique incidence optical system) have the same NA, the center spot shape becomes narrower, and the diffracted light around the center spot light is suppressed, improving the resolution. As a result, the deterioration of contrast is minimized.

As a result, an optical system suitable for observing at high resolution without deteriorating the contrast even if the contrast of an organism is low. Therefore, according to the scanning confocal X-ray microscope of the present invention, clear high-resolution observation of a biological sample is possible. The X-ray source as a point light source according to the present invention is constituted by a laser plasma X-ray source or an X-ray source obtained by combining a pinhole with an X-ray non-point light source (claim 2).

The laser plasma X-ray source generates a plasma by concentrating a high-power laser on a target (target member) and concentrating the laser energy on a minute area, and generates a strong X-ray generated from the plasma. A ray is used as the X-ray source. X-rays from plasma are very powerful and have been applied to various applications. However, in order to obtain strong X-rays, the laser beam must be focused very small, so that the light source becomes very small.

Therefore, if the laser plasma X-ray source is used in the scanning confocal X-ray microscope according to the present invention, the size of the light emitting point of the X-ray source is originally small, so that the size of the light emitting point can be regarded as a point ( It is preferable because the pinhole on the light source side can be omitted by further reducing the size to below the size of the diffraction limit).
Further, it is preferable because the use efficiency of X-rays is increased. Moreover,
If the size of the light emitting point is reduced to a point that can be regarded as a point (below the size of the diffraction limit), the energy of the laser that excites the plasma will be more concentrated, so the excitation laser will need to be small, and the laser plasma X-ray This is very convenient because the source can be miniaturized.

Furthermore, since the generation of X-rays in the laser plasma X-ray source can be controlled by a laser that excites plasma, there is an advantage that it is easy to synchronize with the scanning of the sample container containing the sample. It is preferable to use a grazing incidence reflecting mirror for the X-ray focusing optical system according to the present invention because the use efficiency of X-rays is high. Further, as described above, the grazing incidence optical system has a confocal arrangement (constituting a confocal optical system). 2) It is preferable to combine with an objective optical system having the same NA as the condensing optical system because resolution is improved and contrast deterioration is minimized as shown in the characteristic diagram of FIG.

That is, it is preferable that an optical system suitable for observation with high resolution can be easily formed without deteriorating the contrast even if the contrast is low, such as a living thing. Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

[0041]

【Example】

<Embodiment 1> FIG. 1 is a schematic configuration diagram showing the configuration of a scanning confocal X-ray microscope according to this embodiment. In the scanning confocal X-ray microscope of the present embodiment, an excitation laser beam emitted from a high-power excitation laser 40 is condensed on a metal target 42 by a laser condensing lens 41 to form plasma, and the plasma is generated from this plasma. X-ray objective optical system using X-rays
An X-ray microbeam is formed on the biological sample 4 by 34.

In this embodiment, as shown in the figure, a laser plasma X-ray source 21 is used as an X-ray source, and a grazing incidence reflection type X-ray mirror showing high efficiency is used as an X-ray objective optical system 34. . Since the X-ray objective optical system 34 uses an optical system 100 times the NA of 0.18 on the reduction side, the NA on the X-ray source side is 0.0018, and if the X-ray wavelength to be used is 3 nm, the X-ray source The diffraction limit on the side is about 1.0 μm.

Therefore, in this embodiment, the second harmonic of the YAG laser having a wavelength of 532 nm is used as the excitation laser 40, and the NA of the laser condenser lens 41 is set to about 0.5, so that the laser spot size becomes 0.65 μm. The laser plasma X-ray source can be considered as a point light source. That is, it is not necessary to insert a pinhole or the like again to make a confocal optical system, and it is not necessary to waste X-rays.

A sample container (an example of a sample holder) 23 containing the biological sample 4 is placed on a scanning drive stage (an example of a scanning drive system) 32 to obtain a scanning X-ray image.
Scanning is performed in synchronization with the excitation laser 40 of the laser plasma X-ray source. In this embodiment, a high-output pulse laser such as a Q-switched YAG laser is used as the excitation laser 40. However, since the output is pulse-like, X-rays are also generated in a pulse-like manner. Therefore, the scanning drive stage 32 is operated when the excitation laser is not oscillating.

Specifically, a pulse X is applied to one pixel in advance.
The number of irradiations of a line and the data of one pixel are determined in consideration of image contrast, photon noise, etc., and immediately after irradiation of the specified number of pulses of X-rays, the next pulse X-ray is generated. Before irradiating the sample, the sample is moved to the next pixel to acquire data of the next pixel. These controls are performed by the control device 33.

The X-rays that have passed through the biological sample 4 are similarly enlarged by an X-ray focusing optical system 35 using an obliquely incident reflection type X-ray mirror and projected onto a pinhole 6 to be detected by a detector (X-ray detection). One example of the system) is detected by 31. In the present embodiment, since the same oblique incidence mirror used in the X-ray focusing optical system is used as the X-ray objective optical system, the diffraction limit on the detector side is also 1.0 μm.
m, and therefore a pinhole 6 of about 0.5 to 1 μm is used.

Next, with respect to the image forming characteristics of the scanning confocal X-ray microscope of the present embodiment, as described above, the same oblique incidence mirror is used for the X-ray objective optical system and the X-ray focusing optical system. ing. The imaging characteristics of the X-ray objective optical system alone are as shown in FIG. The grazing incidence mirror used here is
The shielding rate of the annular opening at NA 0.18 (the inner shielding N.
A./outer NA) is 0.75 and the wavelength used is 3 nm.

Since the same X-ray focusing optical system as that of the X-ray objective optical system is used, the focusing characteristics of the X-ray focusing optical system are, as shown in FIG. This is the same as the imaging characteristic of the line objective optical system. Therefore, the effective point spread function of the confocal X-ray optical system in this embodiment is as shown in FIG. 2 (c), and the peak is narrower than that of a normal non-confocal scanning type. Is improved, and the ambient light is reduced to improve the contrast.

Therefore, according to the scanning confocal X-ray microscope of the present embodiment, clear high-resolution observation of a biological sample is possible. <Embodiment 2> FIG. 3 is a schematic diagram showing the configuration of a scanning confocal X-ray microscope according to this embodiment. The scanning confocal X-ray microscope of the present embodiment uses a multilayer reflector for the X-ray objective optical system of the first embodiment.

In general, a laser plasma X-ray source generates X-rays of several wavelengths, but when applied to analysis or the like, a single color may be better in some cases. Therefore, when a multilayer film reflecting mirror is used for the X-ray objective optical system, the X-rays condensed by the X-ray objective optical system become monochromatic, and can be applied to, for example, absorption mapping of a specific wavelength using an absorption edge. Can be.

[0051]

As described above, according to the scanning confocal X-ray microscope of the present invention, a clear high-resolution observation of a biological sample is possible. That is, according to the scanning confocal X-ray microscope of the present invention, a resolution higher than that of a normal confocal microscope is obtained, and the resolution and contrast of the X-ray optical system used in the X-ray microscope are improved, and the imaging characteristics are improved. Can be observed, so that it is possible to observe fine structures with low contrast such as living things.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating a configuration of a scanning confocal X-ray microscope according to a first embodiment.

FIG. 2 is an explanatory diagram illustrating imaging characteristics of the scanning confocal X-ray microscope according to the first embodiment.

FIG. 3 is a schematic configuration diagram illustrating a configuration of a scanning confocal X-ray microscope according to a second embodiment.

FIG. 4 is a conceptual diagram of a confocal microscope.

FIG. 5 is an explanatory diagram showing an imaging characteristic of a confocal microscope.

FIG. 6 is a characteristic diagram showing absorption of an X-ray by a substance.

FIG. 7 is a schematic configuration diagram of an imaging X-ray microscope.

FIG. 8 is a schematic configuration diagram of a scanning X-ray microscope.

FIG. 9 is a conceptual diagram illustrating types of X-ray optical elements.

FIG. 10 is a characteristic diagram illustrating imaging characteristics of an annular aperture.

[Explanation of symbols]

 1 Light source 2, 6 pinhole 3 Objective optical system 4 Sample (biological sample) 5 Focusing optical system 7 Detector 8 Laser 9 Half mirror 10 Scanning optical system 21 X-ray generator (laser plasma X-ray source) 22 X-ray illumination Optical system 23 Sample container (example of sample holder) 24 X-ray magnifying optical system 25 X-ray imaging device 26 Vacuum container 27 Exhaust device 28 Monitor screen 30 X-ray objective optical system 31 X-ray detector (example of X-ray detection system) 32 Scanning drive stage (an example of a scanning drive system) 33 Controller 34 Grazing incidence type X-ray objective optical system 35 Grazing incidence type X-ray focusing optical system 36 Multilayer reflecting mirror X-ray objective optical system 40 High power laser 41 Laser collection Optical lens 42 Target (target member)

Claims (3)

[Claims] At least an X-ray source and X-rays from the X-ray source
An X-ray objective optical system that irradiates a sample held by the sample holder with a ray, a sample holder that holds the sample, a scanning drive system that scans the sample holder, and an X-ray detection system that detects X-rays from the sample. A scanning X-ray microscope comprising: an X-ray focusing optical system that uses the X-ray source as a point light source and that focuses X-rays from the sample between the sample holder and the X-ray detection system. And a confocal optical system formed by providing a pinhole or a slit. 2. The X-ray source as the point light source is a laser plasma X-ray source or an X-ray source obtained by combining a pinhole with an X-ray non-point light source. A scanning confocal X-ray microscope as described. 3. The scanning confocal X-ray microscope according to claim 1, wherein an oblique incidence reflecting mirror is used for the X-ray focusing optical system.