JPH0660959B2 - X-ray spectrometer inspection device - Google Patents

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray spectrometer inspection apparatus.

[Prior art]

A concentrated wavelength scanning X-ray spectroscope (hereinafter referred to as a scanner) using a curved crystal as a spectroscopic element is used in an X-ray microanalyzer (EPMA), a fluorescent X-ray analyzer, and the like. In this scanner, the X-ray scanner incidence point P, the cylindrical curved crystal for spectroscopy 2 ', and the position Q of the X-ray exit slit are
As shown in FIG. 3, the radius of curvature of the dispersive crystal is the diameter,
The center 0'is on the center normal of the dispersive crystal 2 ', and the disperse crystal is located on the circle (Roland circle) passing through the surface center 0 "of the dispersive crystal while the object is centered on the normal 00" of the dispersive crystal. 2'and the position Q of the exit slit are driven. Even if the driving accuracy of the scanner is high, the angle and position of the dispersive crystal and the position of the exit slit must be properly arranged at all scanning wavelengths, that is, arranged so that X-rays are focused on the exit slit. Further, even if the dispersive crystal angle and position are adjusted at a certain wavelength so that the light is condensed at the exit slit, if the wavelength is different from the adjusted wavelength, the condensing position may be slightly displaced from the exit slit. This is a problem of the dispersive crystal itself, but it is necessary to correct the position of the exit slit for each spectral wavelength so that X-rays are focused on the exit slit for each spectral wavelength.
Therefore, the spectral accuracy of the scanner is inspected and adjusted. However, in order to inspect and adjust the scanner using X-rays in the air, a micro focus vacuum sealed type that generates X-rays of a desired wavelength is used. It is necessary to prepare a large number of X-ray tubes or a micro focus vacuum sealed X-ray tube capable of generating X-rays of a desired wavelength by switching wavelengths. Since this is very difficult, EPMA itself is used as an X-ray generator. Therefore, after the scanner is attached to the apparatus, the inside of the apparatus is evacuated and then the inspection is performed.
Therefore, in order to perform the above inspection and adjustment, it is necessary to measure the signal intensity from the detector while adjusting the angle and position of the dispersive crystal and the position of the exit slit. Since it takes about 10 hours, it takes a long time to inspect and adjust the scanner.

[Problems to be Solved by the Invention]

An object of the present invention is to make it possible to easily adjust the angle and position of the crystallizing crystal of the scanner, adjust the position of the exit slit, and inspect the position deviation of the exit slit in the entire scanning wavelength range.

[Means for Solving the Problems]

In a wavelength scanning X-ray spectroscope using a curved crystal, a means for making light incident on either an X-ray incident point or an emission point on a Rowland circle of the spectroscope is arranged, and the X-ray spectroscope is mounted at the curved crystal mounting position. The diameter of the Rowland circle of the line spectrometer is set as a radius, and a cylindrical mirror having a center of curvature is attached on the Rowland circle, and the X-ray emission point or the incident point corresponding to the incident point of the light is centered on the Roland circle of the spectrometer. As a line sensor, a line sensor capable of detecting the amount of incident light and having a position resolution is arranged, and means for calculating the incident light center point from the output signal of the line sensor is provided, and the incident light center at each wavelength position of the X-ray spectrometer is provided. A means for outputting points is provided.

[Action]

The present invention is intended to take out a scanner from a measuring device such as an X-ray microanalyzer, mount the scanner in a dark room or a dark box capable of optical measurement, and to inspect and adjust the spectral characteristics of the scanner in the atmosphere. In a scanner installed in a dark room or a dark box, instead of a dispersive crystal, a cylindrical mirror having a curved surface whose radius is the diameter of the Rowland circle, an emitting element behind the exit slit, and a line at the X-ray irradiation position are used. When the reference position of the sensor is arranged, as shown in FIG. 2, the center of curvature 0 of the cylindrical mirror 2, the line sensor reference position P, and the exit slit position Q are on the circumference of the Rowland circle R, and the arrangement relationship is To arc P0 = arc Q0
Therefore, the light from the light emitting element that enters the scanner from the exit slit position Q is reflected by the cylindrical mirror 2 and condensed at the reference position P of the line sensor. This optical path is
In the scanner, the X-ray is traced from the X-ray incident point by the dispersive crystal to the exit slit, and the opposite path is followed. What kind of path is the optical path by the inspection mechanism using the cylindrical mirror? By investigating, the arrangement of the measuring mechanism using the dispersive crystal can be inspected. Therefore, in the present invention, in the inspection mechanism described above, the converging position of the light emitted from the light emitting element is calculated from the detection result of the light intensity distribution on the line sensor, thereby twisting or exiting the holder for the dispersive crystal. The deviation of the locus of movement of the slit from the ideal locus can be obtained. Since light is used instead of X-rays, it is not necessary to exhaust the vacuum chamber one by one, so that the dispersive crystal and the exit slit of the scanner can be easily moved in a short time. Needless to say, the positional relationship between the light source and the light receiving element may be reversed.

【Example】

FIG. 1 shows an embodiment of the present invention. In FIG. 1, 1
Is a line sensor arranged at a place where a sample is set at the time of measurement, and 600 pieces of 12 μm square photosensitive parts are arranged in a line on a silicon substrate at a pitch of 14 μm, and are attached to a position fine adjustment mechanism. Reference numeral 2 denotes a cylindrical mirror having a diameter of a Rowland circle of the scanner as a radius and having a center of curvature on the Rowland circle, which is held by a dispersive crystal holding unit (not shown). 3 is an exit slit, and 4 is an issuing element (LED) arranged behind the exit slit 3. At the time of measurement, an X-ray detector is arranged instead of the light emitting element 4. The cylindrical mirror 2, the exit slit 3 and the LED 4 are fixed on the mechanism for driving the wavelength scanning under the above-mentioned constant condition, and the scanner A
Are configured. The scanner A is detached from a measuring device such as an X-ray microanalyzer and set in the atmosphere in a dark room or a dark box (not shown) where optical measurement can be performed. After the inspection and adjustment of the spectral characteristics are completed, the measurement is performed. Mounted on the device. In the scanner A, the cylindrical mirror 2, the exit slit 3, and the LED 4 are moved to predetermined spectral wavelength positions S1, S2, S3 by driving the wavelength scanning motor 5. A driver 6 controls the wavelength scanning motor 5. Reference numeral 7 denotes an interface, which appropriately converts the detection signal and the control signal so that communication between the microcomputer 10 and each connection element is properly performed. Reference numeral 8 denotes an AD converter that converts the output signal of the line sensor 1 into a digital signal. A bit conversion unit 9 controls the bit position of the output signal of the line sensor 1. The microcomputer 10 stores the light intensity (P) and the bit position (x value) as a set data as an output signal of the line sensor 1,
A light intensity distribution map as shown in FIG. P1 is displayed. The data of the light intensity distribution map P1 is statistically processed by the microcomputer 10,
By determining the barycentric X value of the light intensity distribution, the position Xc of the light source image can be determined with an accuracy of ± 3 μm, which is the required accuracy of the scanner. Next, the wavelength scanning motor 5
Is driven to scan the wavelength of the scanner A, the position Xc of the light source image with respect to the wavelength λ is measured, and a functional relationship diagram (P2) between the light source image position and the wavelength is created. Since this functional relationship diagram of the light source image position and the wavelength shows the positional deviation of the condensing point in the wavelength scanning, it can be used not only for the accuracy of the scanner but also for the analysis of the cause of the defect of the scanner. In the above-described embodiment, the line sensor is placed at the X-ray incident point of the scanner and the light source is placed behind the X-ray exit slit of the scanner. However, even if this arrangement is reversed, the same effect as in the above-described embodiment can be obtained.

【effect】

According to the present invention, the angle and position of the dispersive crystal that determines the spectral accuracy of the scanner and the position of the exit slit can be optically inspected in the entire wavelength range, so that adjustment and accuracy inspection of the scanner can be performed without vacuum work. It becomes possible to adjust the angle and position of the dispersive crystal of the scanner and to easily measure the position deviation of the exit slit in the entire wavelength scanning in a short time. Analysis has become easy.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention, FIG. 2 is an optical path explanatory diagram of the above embodiment, and FIG. 3 is an optical path explanatory diagram of a scanner. 1 ... Line sensor, 2 ... Cylindrical mirror, 3 ... Exit slit, 4
... LED, 5 ... wavelength scanning motor, 6 ... driver, 7 ...
Interface, 8 ... AD converter, 9 ... Bit converter, 10 ... Microcomputer, A ... Scanner, S1, S2, S3
… Scanner wavelength scanning position, P1… Light intensity distribution map, P2
... A functional relationship diagram between a light source image position and a wavelength.

Claims (1)

[Claims] 1. A wavelength-scanning X-ray spectroscope using a curved crystal, wherein a means for making light incident on either an X-ray incident point or an emission point on a Rowland circle of the spectroscope is arranged, and the curved crystal is used. A cylindrical mirror having a diameter of the Rowland circle of the X-ray spectroscope as a radius and a center of curvature on the Roland circle is attached to the mounting position, and an X-ray emission point or an X-ray emission point corresponding to the incident point of the light on the Roland circle of the spectroscope is attached. Is a line sensor that can detect the amount of light incident around the incident point and has a position resolution, and is provided with means for calculating the incident light central point from the output signal of the line sensor, for each wavelength position of the X-ray spectrometer. 2. An X-ray spectroscope inspection apparatus comprising means for outputting the incident light center point.