JP6492389B1 - X-ray diffraction measurement device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To significantly reduce man-hours and costs for increasing the cost of an apparatus and maintaining the apparatus, and to perform a wide range of inspections in a short time even if the inspection range of a measurement object is wide. Providing equipment. When a measurement object is irradiated with X-rays, slits 19 that allow diffraction X-rays generated at the measurement object to pass through are provided in a circular shape at a position where a diffraction ring is formed, and a radial edge is provided. When the X-ray intensity distribution curve in the radial direction of the diffraction ring when the measurement object is normal and at the position where the X-ray irradiation point is set is regarded as a normal distribution curve with a standard deviation σ, both sides of the normal distribution curve In this case, the positions of 1.5σ to 4σ in FIG. The diffracted X-rays that have passed through the slit 19 are incident on the ionization chamber 20, and the intensity of the current flowing through the electrode of the ionization chamber 20 is detected as the intensity of the diffracted X-rays. [Selection] Figure 3

Description

  The present invention relates to an X-ray diffraction measurement apparatus that irradiates a measurement object with X-rays and measures the intensity of diffraction X-rays generated at the measurement object.

  Conventionally, there is a method using X-ray diffraction as a method for non-destructively measuring the surface hardness of a metallic object. For example, as disclosed in Patent Document 1, this method irradiates an object of a metallic object with X-rays, forms an X-ray diffraction image by diffracted X-rays generated at the object, and In this method, characteristic values (half-value width, integral width, etc.) based on the intensity distribution of diffracted X-rays are obtained, and the surface hardness is obtained using the relationship between the characteristic values obtained in advance and the surface hardness. This method can determine the surface hardness with high accuracy. However, if an inspection is performed to detect an abnormal portion of the surface hardness with a measurement object having a large surface area by this method, the surface hardness is varied while changing the X-ray irradiation point. It is necessary to measure the surface hardness of this part, and it takes an enormous amount of inspection time. This is not limited to the surface hardness, and is the same regardless of the value obtained from the characteristic value based on the intensity distribution of the diffracted X-ray. As an X-ray diffraction measurement apparatus corresponding to this problem, in Patent Document 2 below, a plurality of scintillation counters are arranged at different distances from the optical axis of emitted X-rays, and perpendicular to the surface of the measurement object. 1 shows an X-ray diffraction measurement apparatus that irradiates X-rays and measures the intensity of diffracted X-rays with the plurality of scintillation counters. This X-ray diffractometer is a characteristic value based on the intensity distribution of diffracted X-rays (half-value width, half-width, Integration width, etc.). And since the detection of the X-ray intensity by the scintillation counter can be performed in a short time, even if the X-ray diffractometer is moved at a high speed with respect to the measurement object, the X-ray irradiated part is continuously detected. Can be inspected. Therefore, by using this X-ray diffraction measurement apparatus and moving the measurement object relative to the apparatus, even a measurement object having a wide measurement object range can be inspected in a short time.

Japanese Patent No. 5292568 Japanese Patent No. 6020848

  However, the X-ray diffraction measurement apparatus of Patent Document 2 has a problem that the cost of the apparatus increases because a plurality of scintillation counters are used. In addition, all the scintillation counters must be managed so that the accuracy is maintained, and there is a problem that man-hours and costs for maintaining the apparatus are required.

  The present invention has been made to solve this problem, and an object of the present invention is to provide an X-ray diffraction measurement apparatus that irradiates a measurement object with X-rays and measures the intensity of diffraction X-rays generated at the measurement object. In an X-ray diffraction measurement apparatus that can perform a wide range of inspections in a short time if the measurement object is moved relative to the apparatus, the cost and cost for maintaining the apparatus are greatly reduced. An object of the present invention is to provide an X-ray diffraction measurement apparatus capable of performing the above. Furthermore, an object of the present invention is to provide an X-ray diffraction measurement apparatus having an inspection accuracy equivalent to or higher than that of the X-ray diffraction measurement apparatus disclosed in Patent Document 2, even if the cost increase is significantly suppressed.

  In order to achieve the above object, the present invention is characterized in that X-ray emitting means for emitting X-rays as substantially parallel light toward an object to be measured, and X-rays emitted from the X-ray emitting means A slit that allows diffraction X-rays generated in the measurement object to pass through when irradiated on the measurement object, and is formed in a circular shape at a position where a diffraction ring is formed by the diffraction X-ray, so that the measurement object is normal. When the X-ray intensity distribution curve in the radial direction of the diffraction ring when the X-ray irradiation point on the measurement object is set is regarded as a normal distribution curve with a standard deviation σ, An ionization chamber in which a slit having a radius of 1.5σ to 4σ is formed as an edge in the radial direction and an electrode made of a positive electrode and a negative electrode are provided inside, and a gas to be ionized by X-rays is enclosed. The diffracted X-rays that have passed through are incident and incident Due to the ionization phenomenon of the gas generated by the diffracted X-rays, an ionization chamber in which a current having an intensity corresponding to the intensity of the diffracted X-rays incident through the electrodes flows, and the intensity of the current flowing in the ionization chamber is determined by diffracted X-rays passing through the slit The X-ray diffraction measurement apparatus includes an intensity detection means for detecting the intensity of the X-ray.

  According to this, when X-rays are irradiated on the measurement object, the diffracted X-rays passing through the slit are regarded as a normal distribution curve with a standard deviation σ as an X-ray intensity distribution curve in the radial direction of the diffraction ring. If the 1.5 σ to 4 σ locations on both sides of the normal distribution curve are the lower and upper limits, and the measurement location (X-ray irradiation point) is normal, the X-ray irradiation point may be slightly deviated from the set position. Most of the diffracted X-rays pass through the slit. In contrast, when the intensity distribution of diffracted X-rays changes due to abnormalities in the surface hardness or other characteristics, the X-ray intensity distribution curve becomes a gentler curve than normal, in other words, X When the line intensity distribution curve is regarded as a normal distribution curve with a standard deviation σ, the standard deviation σ becomes larger than that in the normal state, and many diffracted X-rays are blocked by the slits. Therefore, when there is an abnormality that changes the intensity distribution of diffracted X-rays, such as surface hardness, at the measurement location (X-ray irradiation point), the intensity of diffracted X-rays incident on the ionization chamber, that is, the ionization detected by the intensity detection means The intensity of the current flowing through the box changes greatly, and an abnormality at the measurement location can be detected. In other words, the position of the X-ray diffraction measurement apparatus with respect to the measurement object is determined so that the X-ray irradiation point is set, and the measurement object is placed with respect to the apparatus so that the positional relationship between the measurement object and the apparatus does not change significantly. If moved, an X-ray diffraction measurement apparatus having one ionization chamber can detect an abnormality in which the intensity distribution of the diffracted X-ray changes as in the apparatus disclosed in Patent Document 2, which increases the cost of the apparatus and Man-hours and costs for equipment maintenance can be greatly reduced. In addition, the abnormality in which the intensity distribution of the diffracted X-rays changes is not only an abnormality in which the X-ray intensity distribution curve becomes gentle, but also the peak intensity of the X-ray intensity distribution curve due to the presence of a film or rust on the surface of the measurement object. Including abnormalities that become smaller. Also in this case, since the intensity of the diffracted X-rays incident on the ionization chamber changes greatly, an abnormality can be detected.

  Another feature of the present invention is that the X-ray emitting means includes an X-ray tube that emits X-rays and a through hole that allows the X-ray emitted from the X-ray tube to pass through, and the through hole is formed in the ionization chamber. This is because a positive electrode or a negative electrode is formed around the through hole inside the ionization chamber. According to this, the X-ray tube and the ionization chamber can be arranged close to each other, and the X-ray diffraction measurement apparatus can be miniaturized.

  Another feature of the present invention is parallel light irradiating means for irradiating a parallel light of a minute cross section so as to intersect the optical axis of the X-ray emitted from the X-ray emitting means, which intersects the optical axis of the X-ray. When the point to be measured is an X-ray irradiation point on the object to be measured, the parallel light irradiation unit emits parallel light so that the peak point of the X-ray intensity distribution curve is centered in the radial direction of the slit, and the parallel light irradiation unit emits When the parallel light is irradiated onto the measurement object, a part of the scattered light or reflected light generated at the parallel light irradiation point of the measurement object is received by the optical sensor, and the optical axis of the X-ray is received from the light receiving position of the optical sensor. Is an X-ray diffraction measurement apparatus provided with a shift distance detecting means for detecting a distance between a point intersecting with the X-ray irradiation point on the measurement object as a shift distance.

  According to this, when the intensity detected by the intensity detecting means (the intensity of the diffracted X-rays incident on the ionization chamber) changes greatly, the intensity of the diffracted X-rays changes if the deviation distance detected by the deviation distance detecting means also changes greatly. This change is not due to an abnormality in which the intensity distribution of the diffracted X-rays at the measurement location changes, but can be attributed to a change in the positional relationship between the measurement object and the apparatus. In this case, the thickness of the measurement object may be abnormal, the measurement object may be placed in an abnormal manner, or the X-ray diffraction measurement device may be misaligned. The cause of That is, an abnormality in which the intensity distribution of diffracted X-rays changes can be detected more accurately. The point where the parallel light intersects the optical axis of the X-ray is a point where the intensity distribution of the diffracted X-ray passing through the slit is optimal when the X-ray irradiation point matches this point. It is the position of the irradiation point, and in other words, it is the reference X-ray irradiation point. For this reason, the distance between this point and the actual X-ray irradiation point is called a shift distance.

  Another feature of the present invention is that, in the X-ray diffraction measurement apparatus provided with the parallel light irradiation means and the shift distance detection means, the intensity detected by the intensity detection means is compared with a preset pass / fail judgment level. A determination means for performing a pass / fail determination, comprising: a determination means for performing a pass / fail determination after correcting the detected intensity or the pass / fail determination level using the deviation distance detected by the deviation distance detection means.

  According to this, even if the positional relationship between the measurement object and the X-ray diffraction measurement apparatus changes slightly, that is, even if the deviation distance detected by the deviation distance detection means changes slightly from 0, it passes through the slit (ionization). Although the intensity of the diffracted X-ray (incident on the box) changes only minutely, the determination means corrects the intensity detected by the intensity detection means or the pass / fail judgment level so that there is no minute change. If the measurement location (X-ray irradiation point) is normal, the intensity relationship between the intensity detected by the intensity detecting means and the pass / fail judgment level is substantially constant. Therefore, an abnormality in which the intensity distribution of diffracted X-rays changes can be detected with higher accuracy. Note that the correction of the intensity or the pass / fail judgment level detected by the intensity detecting means can be performed using a correction table or a correction formula. In this correction table or correction formula, a normal measurement object is irradiated with X-rays, and the intensity is detected by the intensity detection means while changing the shift distance from 0 to a plus direction and a minus direction. It can be obtained by obtaining the change rate of the detected intensity with respect to each deviation distance.

1 is an overall schematic diagram showing an X-ray diffraction measurement system including an X-ray diffraction measurement apparatus according to an embodiment of the present invention. It is an enlarged view of the X-ray-diffraction measuring apparatus of FIG. It is the figure which looked at the X-ray-diffraction measuring apparatus from the perpendicular direction of the bottom face wall of the X-ray-diffraction measuring apparatus of FIG. It is sectional drawing which cut | disconnected the ionization chamber in the X-ray-diffraction measuring apparatus of FIG. 2 by the plane containing the optical axis of an emitted X-ray. It is the figure which overlapped and showed the intensity distribution curve of the diffraction X-rays which inject into an ionization chamber with the slit which lets a diffraction X-ray pass, (a) is a figure which contrasted the case where a measurement location is normal, and the case where it is abnormal, b) is a diagram showing a case where the X-ray irradiation point has changed from the set position. It is a flowchart of the program which the controller of the X-ray-diffraction measuring system of FIG. 1 performs. It is an enlarged view of the X-ray-diffraction measuring apparatus which concerns on another embodiment of this invention.

  A configuration of an X-ray diffraction measurement system including an X-ray diffraction measurement apparatus according to an embodiment of the present invention will be described with reference to FIGS. This X-ray diffraction measurement system includes an X-ray diffraction measurement device, a high voltage power supply 65, a computer device 70, a tip detection sensor 75, and a moving mechanism having a long stage St that moves at a constant speed, such as a belt conveyor. Is done. The stage St is a plane, the movement direction is parallel to the plane, and the measurement objects OB are placed at regular intervals. Therefore, when the stage St moves, the placed measurement object OB moves and comes directly below the X-ray diffraction measurement apparatus. The X-ray diffraction measurement system detects the intensity of diffraction X-rays by continuously irradiating X-rays from the front end to the rear end on the measurement object OB that comes directly under the X-ray diffraction measurement apparatus. An inspection for detecting an abnormal portion is performed for each measurement object OB. In the present embodiment, the measurement object OB is an iron flat plate.

  In the X-ray diffraction measurement apparatus, an X-ray emitter 10 that emits X-rays and a through-hole 20a that allows the X-rays emitted from the X-ray emitter 10 to pass through the housing 40 are formed at the center. An ionization chamber 20 that receives diffracted X-rays generated at the X-ray irradiation point and a laser irradiator 12 that emits laser light so as to intersect the optical axis of the emitted X-ray are housed. Further, in the housing 40, an image pickup comprising an imaging lens 30 and a line sensor 32 that collect and image a part of scattered light generated at the irradiation point of the laser light emitted from the laser irradiator 12. The unit is housed. Further, the housing 40 includes various circuits that are connected to the X-ray emitter 10, the ionization chamber 20, the laser irradiator 12, and the line sensor 32 to control operation and input detection signals. In FIG. 1, various circuits surrounded by a two-dot chain line outside the housing 40 are accommodated in a two-dot chain line in the housing 40. In FIG. 1, a circuit board, electric wires, fixtures, an air cooling fan, and the like are omitted.

  The housing 40 is formed in a substantially rectangular parallelepiped shape, and includes a bottom wall 40a, a front wall 40b, a top wall 40c, a rear wall 40d, and a side wall 40e. The bottom wall 40a is formed with a circular hole 40a1 that allows X-rays emitted from the X-ray emitter 10 through the through hole 20a in the ionization chamber 20 to pass therethrough and allows diffracted X-rays generated at the X-ray irradiation point to pass. Has been. FIG. 3 is a view of the housing 40 as viewed from the direction perpendicular to the bottom wall 40a. As shown in FIG. 3, the circular hole 40a1 has a slightly smaller diameter than the circular slit 19 formed on the bottom surface of the ionization chamber 20. Largely, it allows the outgoing X-rays to pass through and allows the diffracted X-rays incident on the ionization chamber 20 through the slit 19 to pass therethrough. The optical axis of the X-ray emitted from the through hole 20a in the ionization chamber 20 is substantially perpendicular to the bottom wall 40a and the top wall 40c, and is substantially parallel to the front wall 40b, the rear wall 40d, and the side wall 40e. Further, the side wall 40 e is provided with a connection portion 51, and the housing portion 40 is coupled to the fixture 50 by fixing the connection portion 51 to the fixture 50. The fixture 50 can be finely adjusted in position and posture, and the housing 40 is finely adjusted in position and posture, and X-rays are irradiated from the vertical direction with respect to the plane of the stage St. When the measurement object OB has a standard thickness, the X-ray irradiation point is set to a set position (X-ray laser crossing point described later).

  The X-ray emitter 10 is formed in a long shape, extends in the left-right direction in the figure in the upper part of the housing 40 and is fixed to the housing 40, and supplies a high voltage from a high-voltage power supply 65. The X-ray is emitted from the emission port 11 under the control of the X-ray control circuit 62.

  The X-ray control circuit 62 is controlled by a controller 71 that configures a computer device 70 to be described later, and a high voltage power supply 65 is supplied to the X-ray emitter 10 so that X-rays with a certain intensity are emitted from the X-ray emitter 10. The drive current and the drive voltage supplied from are controlled. Further, the X-ray emitter 10 includes a cooling device (not shown), and the X-ray control circuit 62 also controls a drive signal supplied to the cooling device. Thereby, the temperature of the X-ray emitter 10 is kept constant.

  The ionization chamber 20 has a positive electrode and a negative electrode inside, and encloses a gas that is ionized by radiation, and its operating principle is the same as that generally circulated in the market. When radiation (in this case, X-rays) enters the ionization chamber 20, the enclosed gas is ionized, and a current having an intensity corresponding to the amount of ionization, that is, the intensity of the incident radiation flows between the positive electrode and the negative electrode. The intensity detection circuit 60 that detects the intensity of this current acquires the intensity of the incident radiation (in this case, X-rays). As shown in FIGS. 2 and 3, the ionization chamber 20 is formed in a cylindrical shape, a slit 19 for making X-rays incident on the bottom surface is formed in a circular shape, and a through hole 20a is formed in the center. . The ionization chamber 20 has the bottom surface in contact with the inner wall of the bottom wall 40a and the inside of the housing 40 so that the central axis of the through hole 20a coincides with the optical axis of the X-ray emitted from the X-ray emitter 10. It is fixed to.

  FIG. 4 shows the internal structure of the ionization chamber 20 by a cross-sectional view of the ionization chamber 20 taken along a plane including the optical axis of the outgoing X-ray. This cut surface is a line that passes through the center of the ionization chamber 20 in FIG. 3, but is a line that forms a minute angle with the lateral direction of FIG. This is for the purpose of drawing the slit 19 in the sectional view. In order to make the drawing easier to understand, a triangular mirror 17 described later is omitted from FIG. As shown in FIG. 4, the ionization chamber 20 has a through hole 20 a formed at the center thereof. The through hole 20 a is fixed by fitting the cylindrical pipe 18 into a hole opened at the center of the bottom surface 23. It is fixed by being fitted into a hole opened in the center of a cylindrical insulator 26 fixed to the surface. The cylindrical insulator 26 is fixed by being fitted into a hole formed in the upper surface 22. The cylindrical pipe 18 is made of a material having a high shielding ability for X-rays passing through the through-hole 20a and having an appropriate thickness, and X-rays entering the inside of the ionization chamber 20 through the through-hole 20a are small enough to be ignored. Has been. Lead, copper, iron, or the like can be used as a material having a high X-ray shielding ability. A cylindrical positive electrode 27 is disposed inside the ionization chamber 20 so as to surround the through hole 20 a, and a cylindrical negative electrode 29 is disposed in the vicinity of the cylindrical side surface 21. The cylindrical positive electrode 27 is fixed to a columnar insulator 26, and the insulator 26 is fixed to the upper surface 22, so that it is fixed inside the ionization chamber 20. Similarly, the cylindrical negative electrode 29 is fixed to a cylindrical insulator 28, and the cylindrical insulator 28 is fixed by being fitted into a hole formed in the upper surface 22 to be fixed inside the ionization chamber 20. Has been. It should be noted that the places where the insulator 28 is fitted and fixed to the upper surface 22 are holes formed at several locations near the side surface 21 of the upper surface 22. Part of the positive electrode 27 and the negative electrode 29 protrudes from the insulator 26 and the insulator 28 to the outside of the ionization chamber 20, and a voltage can be applied between the positive electrode 27 and the negative electrode 29 from this location.

  As shown in FIG. 3, the bottom surface 23 of the ionization chamber 20 is formed with a circular slit 19 centered on the central axis of the ionization chamber 20 (the central axis of the through hole 20a). As shown, a radiation transmitting object 19 is fitted and fixed in a hole having a convex cross section formed on the bottom surface 23. The radiation transmitting object 19 may be made of any material as long as it has a high X-ray transmittance and a high mechanical strength. For example, polycarbonate can be used. The inside of the ionization chamber 20 is filled with a gas that is ionized by X-rays. The gas enclosed by the X-rays that have entered the inside of the ionization chamber 20 from the slit 19 is ionized, and the positive electrode 27 and the negative electrode 29 to which a voltage is applied. A current flows between them.

  Passage members 24 and 25 having small holes at the upper and lower ends are fixed to the through-hole 20a (cylindrical pipe 18), and emitted from the emission port 11 of the X-ray emitter 10. X-rays enter the through hole 20 a from the hole of the passage member 24 and exit from the hole of the passage member 25. X-rays emitted from the emission port 11 are diffused X-rays, but pass through the hole of the passage member 24, the through-hole 20a, and the hole of the passage member 25 so that the central axis of the through-hole 20a (the center of the ionization chamber 20). X-rays parallel to the axis.

  When the measurement object OB is irradiated with X-rays through the through-hole 20a, diffracted X-rays are generated at the irradiated portion, and the diffracted X-rays have an angle that matches the Bragg condition with respect to the optical axis of the emitted X-rays. X-rays with high intensity are generated at a certain point, and this is established in all directions perpendicular to the optical axis of the outgoing X-ray, so that a diffraction ring is formed on a plane perpendicular to the optical axis of the outgoing X-ray. This diffraction ring is formed on any plane perpendicular to the optical axis of the outgoing X-ray, but the radius increases as the distance from the X-ray irradiation point of the measurement object OB increases. Further, the X-ray intensity distribution curve in the radial direction of the diffraction ring is a curve close to a normal distribution curve. The slit 19 is formed at a position where the diffraction ring passes through the center in the radial direction when the X-ray irradiation point on the measurement object OB is set at a position (X-ray laser crossing point described later). In other words, the peak position of the X-ray intensity distribution curve in the radial direction of the diffraction ring is formed at a position that coincides with the center of the slit 19 in the radial direction. The width of the slit 19 is set such that the amount of diffracted X-rays incident on the ionization chamber 20 is appropriate. This point will be described in detail later.

  When an operation start command is input from a controller 71 (described later), the intensity detection circuit 60 applies a voltage between the positive electrode 27 and the negative electrode 29 of the ionization chamber 20 and determines the intensity of the current flowing between the positive electrode 27 and the negative electrode 29. The detected current intensity is converted into digital data at a set time interval and output to the controller 71. The intensity detection circuit 60 detects the intensity of the current flowing between the positive electrode 27 and the negative electrode 29 by converting the current into a voltage by passing through a high resistance, or by charging with a capacitor and converting it into a charge amount. The intensity of the current detected as described above corresponds to the intensity of the X-ray incident on the ionization chamber 20, so that when the controller 71 outputs an operation start command, the intensity of the X-ray incident on the ionization chamber 20 is set. It will be entered at different time intervals.

  When the voltage applied between the positive electrode 27 and the negative electrode 29 of the ionization chamber 20 is increased, the ionization chamber 20 becomes a proportional counter, and when it is further increased, it becomes a Geiger-Muller tube (GM tube). The voltage applied between the positive electrode 27 and the negative electrode 29 may be appropriately set as long as a current having an intensity corresponding to the intensity of the diffracted X-ray can be generated. Therefore, the ionization chamber described in the claims can be any ionization chamber, such as a proportional counter and a Geiger-Muller tube, as long as current is generated between the positive electrode and the negative electrode due to the ionization phenomenon of the gas caused by incident X-rays. Also included.

  As shown in FIGS. 2 and 3, the laser irradiator 12 has a central axis parallel to the bottom wall 40a near the front end position in the long direction at the center line position in the short direction of the bottom wall 40a of the housing 40. And it is attached to be perpendicular to the front wall 40b. In the laser irradiator 12, a laser light source 14 is fixed to a cylindrical frame 13 with a fixture 15, and a collimating lens 16 is fixed near the tip of the cylindrical frame 13. The emitted laser light is emitted as parallel light by the collimating lens 16. The laser light source 14 emits laser light when a drive signal is input from the laser drive circuit 61. When the laser drive circuit 61 receives an irradiation start command from a controller 71 described later, the laser light source 14 has a set intensity. A drive signal for emitting laser light is output. The laser beam emitted from the laser irradiator 12 is reflected by the triangular mirror 17 fixed to the bottom surface 23 of the ionization chamber 20 and irradiated onto the measurement object OB. The optical axis of the laser beam after being reflected by the triangular mirror 17 intersects the optical axis of the outgoing X-ray, and the optical axis of the outgoing X-ray and the optical axis of the laser beam are included in one plane. It is. Hereinafter, this plane is referred to as a reference plane. The normal line of the reflecting surface of the triangular mirror 17 is parallel to the reference plane, and the optical axis of the laser light before being reflected by the triangular mirror 17 is also included in the reference plane. Therefore, the reference plane is the same plane as the plane perpendicular to the front wall 40b, including the center line in the short direction of the bottom wall 40a.

  When the point where the optical axis of the laser light reflected by the triangular mirror 17 intersects the optical axis of the emitted X-ray is taken as the X-ray irradiation point of the measurement object OB, the slit 19 on the bottom surface 23 of the ionization chamber 20 Strictly speaking, the triangular mirror 17 is positioned so that the peak point of the X-ray intensity distribution curve in the radial direction of the diffraction ring coincides with the radial center of the slit 19 so that the diffraction ring passes through the center in the radial direction. It has been adjusted. Hereinafter, the intersection of the optical axis of the emitted X-ray and the optical axis of the laser beam is referred to as an X-ray laser intersection. The X-ray laser intersection is an optimum X-ray irradiation point for making the diffracted X-rays incident on the slit 19 in the bottom surface 23 of the ionization chamber 20, and is the position of the set X-ray irradiation point. In other words, it is the reference X-ray irradiation point.

  The imaging lens 30 is fixed to the cylindrical frame 31 on the bottom wall 40a, and the optical axis of the imaging lens 30 is included in the reference plane. The line sensor 32 is fixed in the housing 40 so that the optical axis and the center of the imaging lens 30 intersect. The imaging lens 30 and the line sensor 32 form an imaging unit, and the position of the line sensor 32 with respect to the imaging lens 30 is set so that the depth of field is in a range centered on the X-ray laser intersection. . When laser light is emitted from the laser irradiator 12, scattered light and reflected light are generated at the laser light irradiation point of the measurement object OB, but a part of the scattered light is incident on the imaging lens 30 and the line sensor 32. The line sensor 32 forms an image of the laser beam irradiation point. The line sensor 32 has pixels, such as a CCD or a CMOS, arranged in a line. When a signal from a displacement distance detection circuit 63 (described later) is input, the amount of charge accumulated in each pixel in the displacement distance detection circuit 63 ( A signal having an intensity corresponding to the received light intensity is output in the order of pixels arranged.

  When an operation start command is input from the controller 71 (to be described later), the shift distance detection circuit 63 inputs a signal at a set time interval from the line sensor 32, and converts the signal intensity (corresponding to the received light intensity) into digital data in pixel order. . This is a digital data of the light reception intensity distribution curve in the longitudinal direction of the line sensor 32. Next, the shift distance detection circuit 63 operates a built-in program to calculate the peak of the light reception intensity distribution curve from this digital data. Calculate the position. This is to detect the position of the image of the laser beam irradiation point in the longitudinal direction of the line sensor 32. Further, the distance detection circuit 63 applies the detected peak position to the relationship between the peak position stored in advance (the position of the image of the laser beam irradiation point) and the distance from the X-ray laser intersection of the X-ray irradiation point, The distance of the X-ray irradiation point from the X-ray laser intersection is calculated, and this digital data is output to the controller 71 as a shift distance. As described above, since the X-ray laser intersection is the reference X-ray irradiation point, the deviation distance is the deviation distance from the reference X-ray irradiation point of the actual X-ray irradiation point. Note that this is a method of obtaining the distance by the triangulation method, but the actual relationship of 1: 1 with the peak position of the received light intensity distribution curve is the distance from the X-ray laser intersection at the laser beam irradiation point. is there. However, if the angle of the emitted X-ray with respect to the surface of the measurement object OB is substantially constant, the positional relationship between the laser beam irradiation point and the X-ray irradiation point is 1: 1, so the X-rays at the X-ray irradiation point The distance from the laser intersection also has a 1: 1 relationship with the peak position of the received light intensity distribution curve.

  The relationship between the distance (shift distance) from the X-ray laser intersection of the X-ray irradiation point and the peak position of the received light intensity distribution curve can be obtained as follows. A measurement object OB having a rectangular parallelepiped shape having a reference thickness is placed on the stage St, and an X-ray photosensitive film is placed on the upper surface of the measurement object OB and X-rays are irradiated so that the X-ray irradiation point can be understood. Next, the position of the housing 40 is adjusted so that the laser light matches the X-ray irradiation point, and the peak position of the received light intensity distribution curve at this time is detected. This is the peak position with a shift distance of zero. Then, the rectangular parallelepiped measuring objects OB having different thicknesses are successively placed on the stage St, and the peak position of the received light intensity distribution curve is detected. The value obtained by subtracting the thickness of the first measurement object OB from the thickness of the measurement object OB after the second time is the distance (deviation distance) from the X-ray laser intersection of the X-ray irradiation point. The relationship between the distance (shift distance) from the X-ray laser intersection point of the X-ray irradiation point and the peak position of the received light intensity distribution curve can be obtained. A level is set on the upper surface of the measurement object OB and the upper wall 40c of the housing 40, and the above operation is performed while adjusting the upper surface of the measurement object OB and the upper wall 40c of the housing 40 to be always horizontal. For example, since the X-rays are accurately and vertically irradiated on the upper surface of the measurement object OB, the relationship can be obtained with high accuracy.

  In the vicinity of the side surface of the stage St, an end detection sensor 75 for detecting that the front end and the rear end of the measurement object OB are at positions where the emitted X-rays are irradiated is attached. The end detection sensor 75 confirms the front end and the rear end of the measurement object OB based on whether or not the laser beam near the side surface opposite to the stage St is received, and outputs a signal having a predetermined intensity when receiving the laser beam. If no laser beam is received, no signal is output. The end detection circuit 76 is integrated with the end detection sensor 75. When an intensity of a signal input from the end detection sensor 75 is changed from a predetermined intensity to 0 after an operation command is input from a controller 71 described later, “end detection” is performed. Is output to the controller 71, and a signal indicating "rear end detection" is output to the controller 71 when a predetermined intensity is reached from zero. Note that the line (the optical axis of the laser beam on the opposite side) detected by the end detection sensor 75 is slightly behind the optical axis of the outgoing X-ray with respect to the moving direction of the measurement object OB. When the “leading edge detection” signal is output, the intensity of the diffracted X-ray is detected after a preset time, and when the “rear edge detection” signal is output, the diffracted X-ray is immediately detected. The detection of intensity is stopped. This is because normal inspection cannot be performed in a state where the emitted X-rays are applied to the front and rear edges of the measurement object OB, so that the inspection is not performed in this state.

  The computer device 70 includes a controller 71, an input device 72, and a display device 73. The controller 71 is an electronic control unit having a microcomputer including a CPU, ROM, RAM, a large-capacity storage device, and the like as a main part. The controller 71 executes a program stored in the large-capacity storage device and performs an X-ray diffraction measurement apparatus. In addition to controlling the operation, processing is performed using the input digital data to determine pass / fail. The input device 72 is connected to the controller 71 and is used by an operator for inputting various parameters, operation instructions, and the like. The display device 73 is also connected to the controller 71 and displays various setting states, operating states, inspection results, and the like of the X-ray diffraction measurement system.

  Here, the X-ray laser intersection of the X-ray irradiation point input from the deviation distance detection circuit 63 and the intensity of the diffracted X-ray incident on the ionization chamber 20 input from the intensity detection circuit 60, which is digital data input by the controller 71. The measurement object OB can be inspected (abnormality is detected) from the distance (displacement distance) from. FIG. 5 shows that when the actual X-ray irradiation point coincides with the X-ray laser intersection (reference X-ray irradiation point), the slit 19 is added to the X-ray intensity distribution curve in the radial direction of the slit 19 (radial direction of the diffraction ring). In FIG. 5A, the solid line is an X-ray intensity distribution curve when the measurement location is normal, and the two-dot chain line is the edge of the slit 19. The peak point of the X-ray intensity distribution curve is the center in the radial direction of the slit 19, and the portion where the intensity of the X-ray intensity distribution curve decreases to near 0 becomes the radial edge of the slit 19. Yes. When the X-ray intensity distribution curve is regarded as a normal distribution curve with a standard deviation σ, the edge in the short direction of the slit 19 is set at a position of about 2.5σ. In FIG. 5 (a), the dotted line is an X-ray intensity distribution curve when the intensity distribution of diffracted X-rays changes due to abnormal surface hardness or other characteristics at the measurement location, and this curve is gentler than normal. It becomes a simple curve. In other words, when the X-ray intensity distribution curve is regarded as a normal distribution curve with a standard deviation σ, the standard deviation σ is larger than that at normal time. For this reason, the diffracted X-rays passing through the slit 19 are greatly reduced. Therefore, when there is an abnormality that changes the intensity distribution of diffracted X-rays such as surface hardness at a measurement location (X-ray irradiation point), the intensity of detected diffracted X-rays is greatly reduced. In the present embodiment, the radial edge of the slit 19 is about 2.5σ when the X-ray intensity distribution curve is regarded as a normal distribution curve with a standard deviation σ, but the radial edge of the slit 19 is A large number of measurement target objects OB may be inspected to obtain an optimum location, and is appropriately set within a range of 1.5σ to 4σ. Note that the abnormality in which the intensity distribution of the diffracted X-ray changes is not only an abnormality in which the X-ray intensity distribution curve becomes gentle, but also the peak intensity of the X-ray intensity distribution curve due to the presence of a film or rust on the surface of the measurement object OB. Including abnormalities that decrease. Also in this case, since the diffracted X-rays passing through the slit 19 are greatly reduced, an abnormality can be detected.

  FIG. 5B shows the radial direction of the slit 19 (radial direction of the diffraction ring) when the measurement location is normal and the actual X-ray irradiation point deviates from the X-ray laser intersection (reference X-ray irradiation point). The X-ray intensity distribution curve in FIG. In FIG. 5B, the solid line is an X-ray intensity distribution curve when the X-ray irradiation point coincides with the X-ray laser intersection, and the dotted line and the alternate long and short dash line are when the X-ray irradiation point is deviated from the X-ray laser intersection. The two-dot chain line is the radial edge of the slit 19. The peak position of the X-ray intensity distribution curve of the dotted line and the one-dot chain line deviates from the center in the radial direction of the slit 19, but the diffracted X-ray passing through the slit 19 is only slightly reduced. Therefore, when the measurement object OB moves, if the displacement of the X-ray laser intersection from the surface of the measurement object OB is small, the pass / fail judgment level is appropriately determined and the intensity of the diffracted X-ray detected by the intensity detection circuit 60 is detected. And the pass / fail determination level can be determined (pass / fail detection).

  Also, when there is an abnormality in the thickness of the measurement object OB, an abnormal mounting method of the measurement object OB, or a positional deviation of the X-ray diffraction measurement device, and the deviation of the X-ray irradiation point from the X-ray laser intersection is large. The diffracted X-rays passing through the slit 19 are greatly reduced, but in this case, since the detected deviation distance is large, it is determined that the abnormality is different from the abnormality in which the intensity distribution of the diffracted X-ray changes. Can do. The cause of the abnormality can be determined by preparing a measurement object OB having a standard thickness.

  Further, the abnormality in which the intensity distribution of diffracted X-rays changes has a degree of abnormality, and the degree of gentleness of the X-ray intensity distribution curve shown by the dotted line in FIG. There is also a range in the standard deviation σ. For this reason, even if the degree of decrease in the intensity of the detected diffracted X-rays is small, the pass / fail judgment level is corrected based on the detected deviation distance so that the pass / fail judgment can be accurately performed. This is obtained by storing the relationship between the shift distance and (diffracted X-ray intensity / diffracted X-ray intensity at zero shift distance), and from the detected shift distance (diffracted X-ray intensity / diffracted X-ray at zero shift distance). Intensity) is obtained and corrected by multiplying the reference pass / fail judgment level by (diffracted X-ray intensity / diffracted X-ray intensity at zero shift distance). The relationship between the shift distance and (diffracted X-ray intensity / diffracted X-ray intensity at zero shift distance) is obtained by irradiating X-rays when performing the above-described work for determining the relationship between the shift distance and the peak position of the received light intensity distribution curve. Then, it can be obtained by detecting the intensity of the diffracted X-ray.

  Next, using the X-ray diffraction measurement system including the X-ray diffraction measurement apparatus configured as described above, the measurement objects OB placed on the long stage St moving at a constant speed are inspected one after another. The operation of the X-ray diffraction measurement system will be described with reference to FIG. 6 which is a flowchart of a program executed by the controller 71. First, the operator operates the moving mechanism to start moving the measurement object OB on which the stage St is placed, and then inputs an instruction to start inspection from the input device 72. Thereby, the controller 71 starts execution of the program of the flow shown in FIG. 6 in step S1.

  First, in step S2, the controller 71 starts time measurement using a clock built in the controller 71, and outputs an operation start command to the end detection circuit 76 in step S3. As a result, the end detection circuit 76 detects signals indicating “front end detection” and “rear end detection” each time the front end and the rear end of the measurement object OB are detected by the signal from the end detection sensor 75 as described above. Output to the controller 71. Next, the controller 71 sets m, which is the number for identifying the measurement object OB, to “1” in step S4, and sets n, which is the number for identifying the measurement point, to “0” in step S5. Then, in step S6, it waits for the input of the “tip detection” signal from the end detection circuit 76 to the first measurement object OB. If it is input, it is determined as Yes and the process proceeds to step S7, and the X-ray control is performed in step S7. An output start command is output to the circuit 62, an output start command is output to the laser drive circuit 61 in step S8, a data output start command is output to the shift distance detection circuit 63 in step S9, and the process proceeds to step S10. Then, a data output start command is output to the intensity detection circuit 60. Thereby, X-rays and laser light are irradiated toward the measurement object OB from the X-ray diffraction measurement apparatus (housing 40), and the distance (deviation distance) from the X-ray laser intersection of the X-ray irradiation point and the diffracted X-rays. Intensity digital data is input to the controller 71.

  Next, the controller 71 resets the measurement time to 0 in step S11, and waits for the preset time T to elapse in step S12. As described above, this is because the line (the optical axis of the laser beam on the opposite side) detected by the end detection sensor 75 is slightly behind the optical axis of the outgoing X-ray with respect to the moving direction of the measurement object OB. When the emitted X-rays hit the edge of the measurement object OB, an accurate inspection is not performed. Therefore, the X-ray irradiation point is separated from the edge of the measurement object OB by a minute distance and waits until the inspection can be performed accurately. Is for. Then, when the time T has elapsed, it is determined as Yes and the process goes to step S13, where it is determined whether or not the measurement time is equal to or greater than T + n · Δt. Since n is initially set to “0”, it is immediately determined as Yes and the process goes to step S14, where the diffraction X-ray intensity data I (n, m) input from the intensity detection circuit 60 is stored in memory in step S14. In step S15, the shift distance D (n, m) input from the shift distance detection circuit 63 is loaded into the memory. Next, in step S16, the captured deviation distance D (n, m) is applied to the relationship between the deviation distance stored in advance and (diffracted X-ray intensity / diffracted X-ray intensity at deviation distance 0) to obtain a correction coefficient. (Diffracted X-ray intensity / diffracted X-ray intensity at zero shift distance) is obtained, and the pass / fail judgment level L is multiplied by the obtained correction coefficient to obtain a corrected pass / fail judgment level L ′. In step S17, if the acquired diffraction X-ray intensity data I (n, m) is equal to or higher than the correction pass / fail determination level L ′, the determination is Yes and the process proceeds to step S19, and the acquired diffraction X-ray intensity data is acquired. If I (n, m) is less than the correction pass / fail determination level L ′, the determination is No and the process goes to step S18, where the diffracted X-ray intensity data I (n, m) is stored in another memory area as abnormal location data. After that, go to step S19.

  Next, if the absolute value of the deviation distance D (n, m) acquired in step S19 is equal to or less than the allowable value A, the controller 71 determines Yes and goes to step S21, where the deviation distance D is acquired. When the absolute value of (n, m) exceeds the allowable value A, it is determined as No, the process goes to Step S20, and the deviation distance D (n, m) is stored in another memory area as abnormal location data, and then Step S21. Go to. Next, in step S21, the controller 71 determines whether or not the “rear end detection” signal for the first measurement object OB has been input from the end detection circuit 76. At this stage, since the inspection has just started, No. And go to step S22, increment n and return to step S13. In step S13, the process waits until the measurement time reaches T + n · Δt (in this case, T + Δt). If the measurement time reaches T + n · Δt, the process proceeds to step S14, and the processing in steps S14 to S22 described above is performed. And return to step S13. In this way, every time the measurement time increases by T, T + Δt, T + 2 · Δt and Δt, the diffraction X-ray intensity data I (n, m) and the deviation distance D (n, m) are taken in, and pass / fail judgments are made respectively. In the case of failure (abnormality detection), I (n, m) or deviation distance D (n, m) is stored in another memory area as abnormal part data. Then, when a “rear end detection” signal is input from the end detection circuit 76, it is determined Yes in step S 21, and the process proceeds to step S 23. In steps S 23 to S 26, the X-ray control circuit 62 and the laser drive circuit 61. The output stop command is output to the shift distance detection circuit 63 and the intensity detection circuit 60, and the data output stop command is output. Thereby, the irradiation of the X-ray and the laser beam is stopped until the next measurement object OB comes, and the deviation distance detection circuit 63 and the intensity detection circuit 60 stop outputting data. As described above, the line detected by the end detection sensor 75 (the optical axis of the laser beam on the opposite side) is slightly behind the optical axis of the outgoing X-ray with respect to the moving direction of the measurement object OB. When the end detection sensor 75 detects the rear end, the emitted X-ray does not hit the edge of the rear end of the measurement object OB. Therefore, when the “rear end detection” signal is input, the irradiation of the X-rays and the laser light is immediately stopped and the data output is stopped.

  Next, in step S27, the controller 71 determines whether or not there is diffraction X-ray intensity data I (n, m) or deviation distance D (n, m) stored in another memory area as abnormal part data. Is determined to be No, and the process goes to step S28 to display “pass” on the display device 73 together with the identification information of the measurement object OB corresponding to m = 1. If there is diffracted X-ray intensity data I (n, m) or deviation distance D (n, m) stored in another memory area, it is determined as Yes and the process goes to step S29 to display “fail”. Are displayed on the display device 73 together with the identification information of the measurement object OB. In step S30, from the stored data n, the movement speed F of the stage St stored in advance, the time T, and the distance B from the line detected by the end detection sensor 75 to the optical axis of the emitted X-ray, F (T + n · Δt) −B is calculated, and the distance from the tip of the measurement object OB at the abnormal point is calculated. Furthermore, the ratio between the corrected pass / fail judgment level L ′ and the diffraction X-ray intensity data I (n, m) or the difference between the deviation distance D (n, m) and the allowable value A is stored in advance. Apply the degree table to determine the degree of abnormality. The abnormality degree table divides the ratio between the corrected pass / fail judgment level L ′ and the diffracted X-ray intensity data I, and the difference between the deviation distance D and the allowable value A for each numerical value range. ”,“ Medium ”,“ Large ”,“ Extra Large ”, or“ 1 ”,“ 2 ”,“ 3 ”,“ 4 ”,“ 5 ”. The numerical value of the ratio between the pass / fail judgment level L ′ and the diffracted X-ray intensity data I (n, m) and the numerical value of the difference between the deviation distance D (n, m) and the allowable value A are used as the degree of abnormality. Also good. Then, the controller 71 determines the degree of abnormality determined as the distance from the tip of the abnormal part calculated in this way as the type of abnormality (abnormality in which the intensity distribution of diffracted X-rays has changed, or the deviation distance exceeds an allowable value. Display on the display device 73. In this display, in addition to the numerical display, if the display showing the abnormal location and the degree of abnormality is performed in the figure, the inspection result is easy to understand.

  Next, in step S31, the controller 71 increments m, returns to step S5, and performs the processes of steps S5 to S30 described above on the measurement object OB with m = 2. In step S31, m is incremented and the process returns to step S5, and the same processing is performed on the measurement object OB of m = 3. In this way, the measurement object OB placed on the moving stage St and moving one after another is inspected, and the inspection result is displayed on the display device 73. The operator looks at the result displayed on the display device 73, removes the measurement object OB determined to be unacceptable from the stage St, and separates it from the other measurement objects OB. When the failure is due to the shift distance, it is investigated whether the cause of the abnormality is due to the thickness of the measurement object OB or the method of placing the measurement object OB on the stage St. In addition, when failures due to the shift distance occur continuously, the inspection is stopped as described later, and it is investigated whether the position of the X-ray diffraction measurement device (housing 40) has changed. In any case, if a measurement object OB having a standard thickness is prepared, the cause of the abnormality can be determined. Then, when there is no measurement object OB to be inspected and the operator inputs an inspection stop command from the input device 72, the determination at Step S32 is Yes, the process goes to Step S33, and the end detection circuit 76 is operated at Step S33. Outputs a stop command and stops time measurement using the built-in clock. Next, in step S34, the diffraction X-ray intensity data I (n, m) and the deviation distance D (n, m) stored as abnormal part data are moved to another memory area and used for the next inspection. The memory area to be used is emptied, and the execution of the program is terminated in step S35.

  In this way, after moving the stage St, if an instruction to start an inspection is input from the input device 72, the controller 71 executes the installed program, and thereby the measurement object OB placed on the stage St is detected. The inspection is performed one after another, and the inspection results are displayed on the display device 73 in order. When the operator wants to analyze in detail the cause of the abnormality of the measurement object OB in which an abnormality has been detected, the operator sets the measurement object OB on an X-ray diffractometer that obtains an X-ray diffraction image, What is necessary is just to measure a diffraction image. Note that the pass / fail judgment level L set in the controller 71 requires that the intensity of X-rays irradiated on the measurement object OB be constant. As described above, the X-ray control circuit 62 drives the drive current and the drive voltage supplied from the high voltage power supply 65 to the X-ray emitter 10 so that X-rays with a certain intensity are emitted from the X-ray emitter 10. However, there is a possibility that the intensity of X-rays emitted from the X-ray emitter 10 may change after a long period of time. Therefore, it is necessary to regularly measure the standard measurement object OB and confirm that the diffraction X-ray intensity data I is within the allowable range. When the value is out of the allowable range, the setting of the X-ray control circuit 62 is changed so that the diffraction X-ray intensity data I of the standard measurement object OB is within the allowable range, or the pass / fail judgment level L is set. It is necessary to determine a new allowable range in which the average value of the diffracted X-ray intensity data I at that time is the median value.

  As can be understood from the above description, in the above embodiment, the X-ray diffraction measurement apparatus emits the X-ray as substantially parallel light toward the target measurement object OB and the through-hole. An X-ray emitting means comprising 20a, and a slit 19 through which the diffracted X-rays generated at the measuring object OB pass when the measuring object OB is irradiated with X-rays emitted from the X-ray emitting means, Radial direction of the diffraction ring when the diffraction ring is formed in a circular shape by the diffracted X-ray, the measurement object OB is normal, and the X-ray irradiation point on the measurement object OB is set. When the X-ray intensity distribution curve in FIG. 5 is regarded as a normal distribution curve with a standard deviation σ, a slit 19 is formed so that the positions 1.5σ to 4σ on both sides of the normal distribution curve are edges in the radial direction, and a positive electrode inside 27 and negative electrode 29 An ionization chamber 20 in which a gas that is ionized by X-rays is enclosed, and diffracted X-rays that have passed through the slit 19 enter, and through the electrodes due to ionization of the gas generated by the incident diffracted X-rays An ionization chamber 20 in which a current having an intensity corresponding to the intensity of incident diffracted X-rays flows, and an intensity detection circuit 60 that detects the intensity of the current flowing in the ionization chamber 20 as the intensity of diffracted X-rays that have passed through the slit 19 are provided. X-ray diffraction measurement device.

  According to this, when the X-ray is irradiated onto the measurement object OB, the X-ray intensity distribution curve in the radial direction of the diffraction ring is regarded as a normal distribution curve with a standard deviation σ. When the measurement point (X-ray irradiation point) is normal, the position of 1.5σ to 4σ on both sides of the normal distribution curve is in the range, and if the measurement point (X-ray irradiation point) is normal, the X-ray irradiation point is slightly deviated from the set position. Even so, most of the diffracted X-rays pass through the slit 19. In contrast, when the intensity distribution of diffracted X-rays changes due to abnormalities in the surface hardness or other characteristics, the X-ray intensity distribution curve becomes a gentler curve than normal, in other words, X If the line intensity distribution curve is regarded as a normal distribution curve with a standard deviation σ, the standard deviation σ becomes larger than that in the normal state, and many diffracted X-rays are blocked by the slit 19. Therefore, when there is an abnormality in the intensity distribution of diffracted X-rays such as surface hardness at the measurement location (X-ray irradiation point), the intensity detection circuit 60 detects the intensity of diffracted X-rays incident on the ionization chamber 20. The intensity of the current flowing through the ionization chamber 20 that changes is greatly changed, and an abnormality in the measurement location can be detected. That is, the position of the X-ray diffraction measurement device with respect to the measurement object OB is determined so that the X-ray irradiation point is set, and the measurement object OB is arranged so that the positional relationship between the measurement object OB and the apparatus does not change significantly. , The X-ray diffractometer having one ionization chamber 20 can detect an abnormality in which the intensity distribution of the diffracted X-rays changes as in the prior art. The maintenance man-hours and costs can be greatly reduced.

  Further, in the above embodiment, the X-ray emitting means is configured by the X-ray emitter 10 that emits X-rays and the through hole 20a that allows the X-ray emitted from the X-ray emitter 10 to pass therethrough, and the through hole 20a. Is formed in the ionization chamber 20, and a positive electrode 27 is formed around the through hole 20 a inside the ionization chamber 20. According to this, the X-ray emitter 10 and the ionization chamber 20 can be disposed close to each other, and the X-ray diffraction measurement apparatus can be downsized.

  Moreover, in the said embodiment, the laser beam irradiator 12 which irradiates the laser beam of a micro cross section so that it may cross | intersect the optical axis of the X-ray radiate | emitted from the X-ray emitting means which consists of the X-ray emitter 10 and the through-hole 20a, and When the point that intersects the optical axis of the X-ray in the triangular mirror 17 is the X-ray irradiation point on the measurement object OB, the peak point of the X-ray intensity distribution curve is centered in the radial direction of the slit 19. When the laser beam emitted from the laser beam irradiator 12 and the triangular mirror 17 irradiating the laser beam, and the laser beam emitted from the laser beam irradiator 12 and the triangular mirror 17 are irradiated to the measurement object OB, the laser beam of the measurement object OB. A part of the scattered light generated at the irradiation point is received by the line sensor 32, and the distance between the point where the line sensor 32 receives the light beam intersects the optical axis of the X-ray and the X-ray irradiation point on the measurement object OB. , Re is the X-ray diffraction measuring apparatus equipped with a shift distance detection circuit 63 for detecting a distance.

  According to this, when the intensity detected by the intensity detection circuit 60 (the intensity of the diffracted X-rays incident on the ionization chamber 20) changes greatly, if the deviation distance detected by the deviation distance detection circuit 63 also changes greatly, the diffraction X The change in the intensity of the line can be attributed to a change in the positional relationship between the measurement object OB and the apparatus, not due to an abnormality in which the intensity distribution of the diffracted X-rays at the measurement location changes. In this case, there may be an abnormality in the thickness of the measurement object OB, an abnormal manner of placement of the measurement object OB, or a misalignment of the X-ray diffraction measurement device, but a measurement object OB having a standard thickness is prepared. If you do, you can find out the cause of the abnormality. That is, an abnormality in which the intensity distribution of diffracted X-rays changes can be detected more accurately.

  Moreover, in the said embodiment, it is the program installed in the controller 71 which compares the intensity | strength which the intensity | strength detection circuit 60 detected with the preset acceptance / rejection determination level, and performs acceptance determination, Comprising: A program is provided that performs pass / fail determination after correcting using the deviation distance detected by the detection circuit 63.

  According to this, even if the positional relationship between the measurement object OB and the X-ray diffraction measurement apparatus changes somewhat, that is, even if the deviation distance detected by the deviation distance detection circuit 63 changes slightly from 0, it passes through the slit 19. The intensity of the diffracted X-ray (which enters the ionization chamber 20) changes only minutely, but the program installed in the controller 71 corrects the pass / fail judgment level L so that there is no minute change. If the measurement location (X-ray irradiation point) of the object OB is normal, the intensity relationship between the intensity detected by the intensity detection circuit 60 and the pass / fail judgment level L is substantially constant. Therefore, an abnormality in which the intensity distribution of diffracted X-rays changes can be detected with higher accuracy.

  The implementation of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the object of the present invention.

  In the above embodiment, the present invention is applied to the case where the measurement object OB is placed on the stage St of the moving mechanism and moves at a constant speed. However, when the X-ray diffraction measurement apparatus is carried and a plurality of target portions are inspected. The present invention can also be applied. FIG. 7 is a diagram showing the structure of the X-ray diffraction measurement apparatus in this case. The difference from the X-ray diffractometer of the above embodiment is that the laser irradiator 12, the triangular mirror 17, the imaging lens 30 and the image sensor unit including the line sensor 32 are not provided, and the circular hole 40a1 of the bottom wall 40a is not provided. The cylindrical body 56 is fixed so as to be fitted, and the X-ray irradiation point is set to a set position (reference X-ray irradiation point) by bringing the cylindrical body 56 into close contact with the measurement object OB. And the handle 55 is attached to the upper surface wall 50c so that an X-ray-diffraction measuring apparatus can be conveyed. The operator holds the handle 55 so that the cylindrical body 56 is in close contact with the measuring object OB so that the position where the central axis of the cylindrical body 56 intersects the measuring object OB becomes the inspection target position. The intensity of the diffracted X-ray emitted from the line and incident on the ionization chamber 20 is measured. Thereby, the inspection object location (X-ray irradiation point) can be inspected as in the above embodiment. Further, the cylindrical body 56 is brought into close contact with the measurement object OB so that the diffracted X-rays are not emitted from the X-ray diffractometer, and the X-ray exposure dose of the operator can be reduced to a negligible level. Note that the present invention can also be applied to the case where the X-ray diffraction measurement device is fixed as in the above-described embodiment and the measurement object OB is repeatedly placed on the stage St and continuously inspected. it can.

  Moreover, in the said embodiment, although the deviation distance from the X-ray laser intersection (reference | standard X-ray irradiation point) of an X-ray irradiation point was detected and the pass / fail determination level was corrected, the pass / fail determination level is corrected. Instead, the position of the X-ray diffraction measurement device may be controlled so that the detected deviation distance is always zero. In this case, a mechanism for moving the X-ray diffraction measurement device (housing 40) in the optical axis direction of the emitted X-ray is provided, and every time the deviation distance is detected, the detected X-ray diffraction measurement device (housing) is detected. The feedback control may be performed so that 40) moves. This form is effective when the surface of the measurement object OB is uneven, or when the movement direction of the measurement object OB and the surface of the measurement object OB are not parallel (when the surface is inclined). is there.

  Further, when the degree of unevenness of the surface of the measurement object OB is large or when the moving direction of the measurement object OB and the angle formed by the surface of the measurement object OB differ from place to place, the deviation distance is always 0 and the measurement is performed. In addition to the position of the X-ray diffraction measurement device, the posture may be controlled so that the optical axis of the emitted X-ray is always perpendicular to the surface of the object OB. In this case, in addition to the mechanism for moving the X-ray diffraction measurement device (housing 40) in the direction of the optical axis of the emitted X-ray, the X-ray diffraction measurement device (housing 40) is parallel to the moving direction of the measurement object OB. A mechanism for changing the tilt angle around two axes is provided, and the angle formed by the optical axis of the outgoing X-ray with respect to the normal line of the surface of the measurement object OB is detected at a minute time interval, and this angle becomes 0 each time it is detected. The attitude of the X-ray diffraction measurement apparatus (housing 40) may be feedback-controlled so that The angle formed by the optical axis of the emitted X-ray with respect to the normal of the surface of the measurement object OB is provided with an area sensor that receives the reflected light of the laser light emitted from the laser irradiator 12 via the triangular mirror 17. Detection may be performed from the light receiving position of the sensor.

  In the above embodiment, the pass / fail judgment level L is obtained by applying the shift distance detected by the shift distance detection circuit 63 to the relationship stored in advance (diffracted X-ray intensity / diffracted X-ray intensity at zero shift distance). To pass / fail judgment level L ′, and pass / fail judgment is made. However, instead of this, I (n, m), which is the intensity of the diffracted X-ray detected by the intensity detection circuit 60 (the intensity of the diffracted X-ray incident on the ionization chamber 20), can be obtained from the deviation distance (diffracted X-ray intensity). / Diffraction X-ray intensity at deviation distance 0) may be divided into I (n, m) ′ to determine pass / fail.

  In the second embodiment, the laser beam emitted from the laser irradiator 12 intersects the optical axis of the X-ray via the triangular mirror 17, and the X-ray laser intersection becomes the reference X-ray irradiation point. However, other than laser light may be irradiated as long as parallel light having a minute cross-sectional diameter can be irradiated. For example, incoherent light such as LED light may be irradiated as parallel light having a minute cross-sectional diameter by passing through a cylindrical pipe having a minute inner diameter.

  Moreover, in the said embodiment, although the slit 19 was formed in the bottom face 23 of the ionization chamber 20, even if there exists a slit before the diffraction X-rays inject into the ionization chamber 20, the X-ray intensity distribution curve in the radial direction of a diffraction ring Is regarded as a normal distribution curve with a standard deviation σ, it is only necessary that the radial edge of the slit is located at 1.5σ to 4σ on both sides of the normal distribution curve. Therefore, the bottom surface 23 of the ionization chamber 20 may be provided with an entrance having a large area, and a circular flat plate having a slit formed in front of the bottom surface 23 may be disposed.

  In the above embodiment, the X-ray diffraction measurement device (housing 40) is fixed, and the stage St on which the measurement object OB is placed is moved by a moving mechanism. However, since the present invention can be applied if the measurement object OB moves relative to the X-ray diffraction measurement apparatus (housing 40), the X-ray diffraction measurement apparatus can be used when the measurement object OB is fixed. The (housing 40) may be set in a moving mechanism, and the X-ray diffraction measurement device may be a system that moves relative to the measurement object OB.

  Moreover, in the said Embodiment 2, as a test result of the measurement object OB, the pass / fail judgment result and the abnormal location and the degree of abnormality in the case of failure are displayed on the display device 73. However, other than this, what can be calculated by the diffraction X-ray intensity data I (n, m) or the shift distance D (n, m) may be calculated and displayed. For example, a diffraction X-ray intensity change curve in the moving direction, an average value, a maximum value, a minimum value, and a fluctuation range calculated from the curve may be displayed, or the surface profile of the measurement object OB in the moving direction or the calculated value. You may display a fluctuation range, Ra value, and RMS value.

  In the above embodiment, the end detection sensor 75 detects the front end and the rear end of the measurement object OB based on whether or not the laser light emitted from the opposite side of the stage St is received. 75 may be of any operating principle as long as the front and rear ends of the measurement object OB can be detected. For example, when the edge detection sensor 75 has an imaging function, a bright spot or a special mark is provided on the opposite side of the stage St, and the bright spot or the special mark disappears or appears from the captured image. It is also possible to detect the leading edge and the trailing edge.

  In the above embodiment, the shift distance is detected based on the light receiving position of the laser light irradiation point imaged on the line sensor 32 by the imaging lens 30. However, when the object to be measured OB is limited to a flat surface with a uniform thickness, and there is a possibility that only the total thickness changes, the reflected light of the laser beam is used instead of the line sensor. It is also possible to detect light by a light sensor that can detect the light receiving position, and to detect the shift distance by the light receiving position.

  In the above embodiment, the deviation distance is detected and the pass / fail judgment level L is corrected. However, the manufacturing process is managed so that the thickness of the measurement object OB is constant, and the plane of the stage St is If it is parallel to the moving direction with high accuracy, the pass / fail judgment level L is determined to be constant, and only when an abnormality is detected, an abnormality is determined after checking whether there is any change in the deviation distance. Also good. Also in this case, the imaging lens 30 and the line sensor 32 may be replaced with an optical sensor that can detect the light receiving position of the reflected light of the laser light, and the shift distance may be detected.

  Furthermore, in this case, an abnormality in how to place the measurement object OB and a change in the attachment position of the X-ray diffraction measurement apparatus (housing 40) can be detected by means provided in addition to the X-ray diffraction measurement system. If so, an X-ray diffraction measurement apparatus that does not include the laser irradiator 12, the triangular mirror 17, the imaging unit including the imaging lens 30 and the line sensor, and the shift distance detection circuit 63 may be used. Further, if the edge of the slit 19 in the radial direction is located at 1.5σ to 4σ of the normal distribution curve with the standard deviation σ as described above, the peak position of the X-ray intensity distribution curve is from the center of the slit 19. It may be shifted.

  In the above embodiment, the ionization chamber 20 is provided with the through-hole 20a, and the X-ray emitted from the X-ray emitter 10 is emitted through the through-hole 20a. The X-ray diffraction measurement apparatus was made small by arranging the box 20 close to the box 20. However, if the X-ray diffractometer is allowed to be large, an X-ray emitter 10 and a cylindrical pipe through which X-rays pass are arranged in front of the ionization chamber 20 with respect to the emission direction of the emission X-ray. 20 may not be provided with the through hole 20a.

DESCRIPTION OF SYMBOLS 10 ... X-ray emitter, 11 ... Outlet, 12 ... Laser irradiator, 13 ... Frame, 14 ... Laser light source, 15 ... Fixing tool, 16 ... Collimating lens, 17 ... Triangular mirror, 18 ... Cylindrical shape Pipe, 19 ... slit, 20 ... ionization chamber, 20a ... through hole, 24, 25 ... passage member, 26 ... insulator, 27 ... positive electrode, 28 ... insulator, 29 ... negative electrode, 30 ... imaging lens, 31 ... frame Body, 32 ... Line sensor, 40 ... Housing, 40a ... Bottom wall, 40a1 ... Circular hole, 40b ... Front wall, 40c ... Top wall, 40d ... Rear wall, 40e ... Side wall, 50 ... Fixing device, 51 ... Connection 55: Handle, 70 ... Computer device, 71 ... Controller, 72 ... Input device, 73 ... Display device, 75 ... End detection sensor, St ... Stage, OB ... Measurement object

Claims (4)

X-ray emitting means for emitting X-rays as substantially parallel light toward the target measurement object;
When the measurement object is irradiated with X-rays emitted from the X-ray emission means, it is a slit that allows diffraction X-rays generated at the measurement object to pass through, and a diffraction ring is formed by the diffraction X-rays. The X-ray intensity distribution curve in the radial direction of the diffraction ring when the measurement object is normal and the X-ray irradiation point on the measurement object is set is standard. When considered as a normal distribution curve of deviation σ, a slit in which 1.5σ to 4σ locations on both sides of the normal distribution curve are edges in the radial direction;
An ionization chamber in which an electrode composed of a positive electrode and a negative electrode is provided, and a gas that is ionized by X-rays is enclosed therein, and the diffracted X-rays that have passed through the slit enter the gas generated by the incident diffracted X-rays An ionization chamber in which a current of an intensity corresponding to the intensity of the incident diffracted X-rays flows through the electrode due to the ionization phenomenon of
An X-ray diffraction measurement apparatus comprising: an intensity detection unit configured to detect an intensity of a current flowing through the ionization chamber as an intensity of a diffracted X-ray that has passed through the slit. The X-ray diffraction measurement apparatus according to claim 1,
The X-ray emitting means includes an X-ray tube that emits X-rays and a through hole that allows the X-rays emitted from the X-ray tube to pass through.
The X-ray diffraction measuring apparatus, wherein the through hole is formed in the ionization chamber, and the positive electrode or the negative electrode is formed around the through hole in the ionization chamber. The X-ray diffraction measurement apparatus according to claim 1 or 2,
Parallel light irradiation means for irradiating parallel light of a minute cross section so as to intersect with the optical axis of the X-ray emitted from the X-ray emission means, and a point intersecting the optical axis of the X-ray is in the measurement object Parallel light irradiation means for irradiating parallel light so that the peak point of the X-ray intensity distribution curve is the center in the radial direction of the slit when it is an X-ray irradiation point;
When the parallel light emitted by the parallel light irradiation means is irradiated onto the measurement object, a part of the scattered light or reflected light generated at the parallel light irradiation point of the measurement object is received by an optical sensor, and the light A deviation distance detecting means for detecting, as a deviation distance, a distance between a point intersecting the optical axis of the X-ray from a light receiving position of the sensor and an X-ray irradiation point on the measurement object. X-ray diffraction measurement device. In the X-ray-diffraction measuring apparatus of Claim 3,
A determination unit that performs a pass / fail determination by comparing the intensity detected by the intensity detection unit with a preset pass / fail determination level, wherein the deviation detected by the shift distance detection unit is the detected intensity or the pass / fail determination level. An X-ray diffraction measurement apparatus comprising: a determination unit that performs pass / fail determination after correcting using a distance.

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