JP2006220640A - X-ray stereo fluoroscope and stereo observation method using the same - Google Patents

Abstract

By using X-rays, it is possible to observe internal structures and detect internal defects regardless of the size and shape of the subject, and to reduce the size of the apparatus with a simple structure that rotates the subject. Providing an X-ray stereo fluoroscope with excellent versatility and handling.
An X-ray source, an angle setting mechanism that rotatably holds the subject, a planar image sensor that is disposed opposite to the X-ray source with the subject interposed therebetween and detects a transmission image of the subject, And a display for stereo-displaying the transmission image detected by the image sensor.
[Selection] Figure 2

Description

  The present invention relates to an X-ray stereo fluoroscope for stereoscopic viewing of a subject in a nondestructive inspection or the like and a stereo observation method using the same.

Conventionally, cone beam X-ray computed tomography (XCT) has been used as a method for observing the internal structure of a subject, detecting internal defects, and the like in a nondestructive inspection. Thereby, for example, an electrical connection failure of a solder portion of various electronic components mounted on a substrate or the like is detected, and the introduction of a defective product is prevented in advance.
However, this XCT image processing requires images taken from various angles, which takes time to shoot and requires a great deal of time and effort to process 3D images, and is mass-produced in factories and the like. It was not suitable as an inspection method.
Therefore, various studies have been made to solve these problems. For example, it is assumed that stereo display is performed using an X-ray image. Patent Document 1 states that “the observer distance measurement unit measures the distance between the monitor that performs stereo display and the observer of the X-ray image and Based on the distance detected by the person distance measurement unit, the image distance control unit automatically adjusts the distance between the centers of the two X-ray images displayed in stereo on the monitor screen so that the observation parallax and the shooting parallax for the stereo display are substantially equal. Thus, a digital X-ray imaging apparatus that makes it possible to perform stereo display appropriately is disclosed.
In addition, as a method for performing stereo observation with a transmission electron microscope (Patent Document 2), “a plurality of observations are performed by changing the incident angle of an electron beam on an amorphous body, and the results of the plurality of observations are synthesized. An observation method using a transmission electron microscope characterized by performing three-dimensional observation of defects ”is disclosed.
Japanese Patent Laid-Open No. 10-5206 JP 2004-1111839 A

However, the above conventional techniques have the following problems.
(1) The digital X-ray imaging apparatus of (Patent Document 1) is mainly used in the medical field. By stereo imaging using an image intensifier, three-dimensional information on an affected part of a subject can be obtained at an operation site or the like. The X-ray tube and the image intensifier supported opposite to each other with the subject interposed therebetween must be rotated around the subject to perform imaging, and the mechanism is complicated and the apparatus is large. It had the problem of becoming.
In addition, since the input surface is a spherical surface, distortion is likely to occur in the image, and in order to improve the distortion, the distance between the X-ray tube and the image intensifier must be 1 m or more. There was a problem that the object was unsuitable for small industrial applications.
(2) In the observation method using the transmission electron microscope of (Patent Document 2), it is necessary to thin the subject to a thickness of 200 nm or less in order to transmit the electron beam, and the observation target is limited and lacks versatility. Had problems.
In addition, stereo observation using an image obtained by irradiating parallel electron beams is pseudo, and unlike an actual stereo image, information in the depth direction cannot be obtained, and three-dimensional There was a problem that observation was difficult and lacked practicality.

  The present invention solves the above-described conventional problems. By using X-rays, it is possible to observe an internal structure, detect an internal defect, and the like regardless of the size and shape of the subject, and to simply rotate the subject. Providing an X-ray stereo fluoroscope that is versatile and easy to handle with a structure that can be miniaturized, and can perform accurate image processing in a short time using it, making stereo recognition easy and simple The object is to provide a stereo observation method that can obtain three-dimensional information and has excellent practicality.

In order to solve the above problems, the X-ray stereo fluoroscopic apparatus of the present invention and the stereo observation method using the same have the following configurations.
According to a first aspect of the present invention, there is provided an X-ray stereoscopy apparatus, an X-ray source, an angle setting mechanism for rotatably holding the subject, and the subject disposed so as to face the X-ray source with the subject interposed therebetween. A planar image sensor that detects a transmitted image of the image, and a display that displays the transmitted image detected by the image sensor in stereo.
This configuration has the following effects.
(1) Since it has an angle setting mechanism that holds the subject in a freely rotatable manner, the subject can be rotated by the angle setting mechanism, and the angle formed by the surface of the subject and the surface of the image sensor can be easily set. It is possible to irradiate X-rays from an X-ray source and easily take a transmission image of the subject at an arbitrary angle.
(2) Since the X-ray source and the planar image sensor are arranged opposite to each other with the subject interposed therebetween, a transmitted image of the subject can be detected with high accuracy, and the reproducibility of stereo display by the display device is excellent.
(3) By using an X-ray source, it is possible to reliably observe the internal structure of the subject, detect internal defects, etc. regardless of the size and shape of the subject, and is excellent in practicality and versatility.

  Here, at least parts other than the display device of the X-ray fluoroscopic apparatus are covered with a shielding box, and the X-ray does not leak outside the X-ray fluoroscopic apparatus. An open / close door is provided in the shielding box. Thereby, fixation of the subject to the angle setting mechanism and recovery of the subject from the angle setting mechanism can be easily performed. When a window with an X-ray shielding glass is provided in the shielding box or the open / close door, the operation of the angle setting mechanism can be confirmed directly from the outside. When opening and closing doors are provided on both the left and right sides of the shielding box, the subject can be taken in and out from the left and right opening and closing doors. Therefore, it is possible to easily incorporate the X-ray fluoroscope into the inspection line and automate the work. And is highly efficient.

The angle setting mechanism may be any mechanism that can hold the subject so as to be rotatable around at least one axis. For example, the subject is fixed to an arm or table having a rotating shaft, and the rotating shaft is rotated manually or by a motor such as a pulse motor or servo motor, or one end of the arm or table is pulled by a piston cylinder or the like. Or what is pressed and rotated around the rotation axis is preferably used. Alternatively, the subject may be held using a multi-joint arm or the like having two rotation axes orthogonal to each other that rotate the subject in the left-right direction and the front-rear direction. Accordingly, the subject can be tilted (rotated) in the depth (front-rear) direction, and the thickness direction can be emphasized and displayed. In particular, a thin plate-like specimen can be easily observed, and is excellent in versatility and practicality.
The angle setting mechanism preferably fixes the subject so that the surface of the subject and the surface of the image sensor are substantially parallel in the initial state. Accordingly, when the subject is rotated by the angle setting mechanism, the angle can be easily set, and a transmission image of the subject can be detected at an accurate angle.
As a method for fixing the subject, a method of directly holding the subject, a method of attaching with a double-sided tape or the like, a method of sucking and adsorbing with air, and the like can be used.

  In the stereo display, by displaying two images with different imaging angles, the subject can be recognized as a three-dimensional object based on the difference in imaging angles (imaging parallax). When the rotation axis serving as the rotation center of the subject is located closer to the image sensor than the subject, the entire subject can be rotated from the rotation axis to the X-ray source side. As a result, when a stereo display is performed, the entire subject can be displayed as a three-dimensional object that exists in front of the display screen, that is, relatively near the observer, and the subject can be easily recognized as a three-dimensional object. In particular, the position where the internal defect is generated can be easily grasped, and an arbitrary position of the subject can be easily indicated on the screen.

As the image sensor, a CCD type or CMOS type is preferably used. Since the image sensor is formed in a planar shape, distortion is hardly generated in the image, the apparatus can be easily miniaturized, and can be suitably used for observation of a minute object.
Any display device may be used as long as it can display a planar image in stereo. An anaglyph 3D display using red / blue glasses, a 3D cross display or a parallel 3D display using autostereoscopic viewing, a liquid crystal display or 3D glasses capable of independent 3D display, or a display capable of screen switching And a combination of liquid crystal shutter glasses can be used.
In particular, stereoscopic glasses do not require a large display, so the entire apparatus can be downsized, and are inexpensive and excellent in space saving.

  The X-ray fluoroscopic apparatus can control the angle setting mechanism by including a personal computer as a control unit. Further, the transmission image data can be stored in various storage media such as a hard disk, MO, CD, and DVD provided in the control unit. Thereby, management of the stored data can be easily performed, and the data can be taken out and displayed on the display device as appropriate, or the image can be processed by image processing software or the like.

A second aspect of the present invention is the X-ray fluoroscopic apparatus according to the first aspect, wherein the angle setting mechanism includes a tilt table on which the subject is fixed and two shafts orthogonal to the tilt table. And a rotation holding portion that is rotatably held around.
With this configuration, in addition to the operation of the first aspect, the following operation is provided.
(1) The angle setting mechanism includes a rotation holding unit that rotatably holds the tilt table on which the subject is fixed around two axes orthogonal to each other. Therefore, the transmission angle and observation angle of the transmission image can be set arbitrarily, and the versatility and practicality are excellent.

Here, the rotation holding unit may be any unit that can hold the tilt table so as to be rotatable around two axes orthogonal to each other. For example, an arm portion that rotatably holds a left-right direction rotation shaft that rotates the tilt table in the left-right direction, and a front-rear direction rotation shaft that is disposed on the arm portion orthogonal to the left-right direction rotation axis are provided. Are preferably used. In addition, flexible joints are placed opposite each other on the four corners of the tilting table or two axes that are orthogonal to each other at the approximate center of the tilting table (left and right and both front and rear ends of the tilting table), and selected by a motor such as a pulse motor or servo motor. It may be moved up and down automatically. As the flexible joint, one having an expansion / contraction mechanism in addition to two degrees of freedom of rotation is suitably used. For example, an elastic body such as a spring or rubber may be disposed at the end of a universal joint or the like, or a spherical joint having two degrees of freedom of rotation may be slidably held in the long hole.
When the XY stage is provided on the tilt table, the subject can be moved back and forth and left and right within a plane parallel to the image sensor, and an arbitrary portion of the subject can be selected and observed.

A third aspect of the present invention is the X-ray fluoroscopic apparatus according to the first or second aspect, wherein the reflection is provided between the X-ray source and the subject and reflected from the surface of the subject. A reflection mirror that reflects light, and an optical camera that has a focal point at a position optically equidistant from the X-ray source and that captures a surface image of the subject reflected by the reflection mirror And a configuration provided with.
With this configuration, in addition to the operation of the first or second aspect, the following operation is provided.
(1) Since a reflection mirror is provided between the X-ray source and the subject and reflects reflected light reflected from the surface of the subject, the subject reflected by the reflection mirror is added to the transmission image by X-rays. The surface image of the specimen can be taken with an optical camera, and the surface of the specimen can be observed.
(2) By providing an optical camera having a focal point at a position optically equidistant from the X-ray source to the subject, a surface image of the subject is photographed at an angle of view that is substantially the same as the X-ray transmission image. Therefore, it is not necessary to perform special image processing such as enlargement or reduction on the transmission image or the surface image, the comparison between the transmission image and the surface image is easy, and the handleability of the image data is excellent.

Here, even if a reflection mirror is disposed between the X-ray source and the subject, the X-rays emitted from the X-ray source pass through the reflection mirror, so the reflection mirror can capture a transmission image using X-rays. There is no impact. Thereby, the transmission image and the surface image can be simultaneously captured, and the working time can be greatly shortened. In addition, by capturing the transmission image and the surface image at the same time, there is no displacement when the transmission image and the surface image are displayed in an overlapping manner, and the structure and arrangement of the subject can be accurately grasped and reliable. Excellent in properties.
A single focus lens, a zoom lens, or the like can be used as the lens of the optical camera. Since the single focal length lens has a fixed focal length and a fixed angle of view, it does not require adjustment of the optical system during use, and is excellent in handling. In addition, the lens aberration is smaller than that of a zoom lens, and a high-quality image can be taken, which is excellent in reliability.
Similar to the transmission image, the surface image can be stored in various storage media arranged in the control unit.

A fourth aspect of the present invention is the X-ray fluoroscopic apparatus according to the third aspect, wherein the display unit displays the transmission image and the surface image in an overlapping manner. It has the composition which is.
With this configuration, in addition to the operation of the third aspect, the following operation is provided.
(1) By displaying the transparent image and the surface image in an overlapping manner, it is possible to express the state of seeing through the inside of the real object, making it easy to grasp the three-dimensional sense of distance, and understanding the structure and arrangement of the subject. It is easy to perform alignment and the like.
Here, the transmission image and the surface image can be processed by image processing software or the like as necessary. By changing the size of the image, the transmittance of the surface image, and the like, the display can be performed in a state that is easy for the operator to observe, and more accurate information can be obtained.

The stereo observation method according to claim 5 sets the angle between the surface of the subject and the surface of the image sensor by rotating the subject by an angle setting mechanism in which the subject is rotatably held. A plane disposed opposite to the X-ray source by irradiating the subject with X-rays from the X-ray source at at least two types of angles set in the detection angle setting step and the detection angle setting step A transmission image detection step of detecting a transmission image of at least two types of angles of the subject with a shaped image sensor, and two types of transmission images having different angles from the transmission images detected in the transmission image detection step And a stereo display step of selecting and displaying in stereo on a display device.
This configuration has the following effects.
(1) By the detection angle setting step, the subject can be rotated to easily set the angle between the surface of the subject and the surface of the image sensor, and the subject can be selected by arbitrarily selecting the imaging angle of the transmission image. Can be fixed.
(2) Through the transmission image detection step, the subject can be irradiated with X-rays from the X-ray source at at least two types of angles set in the detection angle setting step, and placed opposite to the X-ray source with the subject interposed therebetween. At least two types of transmission images of the subject can be detected by the planar image sensor.
(3) By the stereo display process, two types of transmission images having different angles can be selected from the transmission images detected in the transmission image detection process and displayed in stereo on the display, and the subject can be accurately displayed in a short time. The state and position of internal structures and internal defects can be observed three-dimensionally.

  Here, the rotation angle set in the detection angle setting step can be appropriately selected. When the angle at which observation is desired is known, two kinds of angles can be set and only two transmission images necessary for stereo display can be taken. It is also possible to perform observation by combining arbitrary angles after taking a large number of transmission images while changing the angle little by little. Furthermore, when performing stereo display, if one of the two images is fixed and the other image is continuously switched to an image with a different angle, the image can be displayed while changing the viewing angle like a movie. it can. At this time, since the magnification in the depth direction changes according to the viewing angle, it is possible to select an angle at which observation is easy while viewing the screen, and the observation workability is excellent. In addition, when two images of stereo display are continuously switched and displayed at different angles at the same time, observation can be performed while changing the viewpoint while rotating the entire subject. Thereby, observation from various angles can be performed continuously in a short time, and observation of the internal structure and internal defects of the subject is easy and excellent in practicality.

The invention according to claim 6 is the stereo observation method according to claim 5, and is reflected from the surface of the subject by a reflecting mirror disposed between the X-ray source and the subject. A surface image capturing step of reflecting a reflected light and capturing a surface image corresponding to a transmitted image of the subject with an optical camera having a focal point at a position optically equidistant from the X-ray source. It has the structure provided with.
With this configuration, in addition to the operation of the fifth aspect, the following operation is provided.
(1) The surface image of the subject corresponding to the transmitted image is reflected by reflecting the reflected light reflected from the surface of the subject with a reflection mirror disposed between the X-ray source and the subject in the surface image capturing step. Can be accurately photographed with an optical camera.
(2) By disposing the optical camera so that the distance from the focal point of the optical camera used in the surface image capturing step to the subject is optically equidistant with the distance from the X-ray source to the subject, Since it is possible to obtain a surface image of a subject taken with an angle of view almost the same as a transmission image by X-rays, processing such as overlaying of the transmission image and the surface image is performed without performing complicated image processing or the like. Therefore, the data processing time can be shortened.

  Here, the surface image photographing step can be performed independently of the transmission image detection step or can be performed simultaneously with the transmission image detection step. When the front surface image capturing step and the transmission image detecting step are performed at the same time, it is not necessary to set the photographing angle again, and the photographing can be performed in a short time. Further, since the transmission image and the surface image can be taken at exactly the same angle, there is no occurrence of misalignment or the like when the two images are superimposed and displayed, and the observation reliability is excellent.

A seventh aspect of the present invention is the stereo observation method according to the sixth aspect of the present invention, comprising: a hybrid display step in which the transmission image of the subject and the surface image corresponding thereto are superimposed and displayed in stereo on the display. It has the composition which is provided.
With this configuration, in addition to the operation of the sixth aspect, the following operation is provided.
(1) Since the hybrid display step can superimpose two types of surface images corresponding to two types of transmission images of the subject taken at different angles and display them in stereo, the surface shape and internal state of the subject can be displayed. They can be displayed simultaneously, the three-dimensional structure of the subject can be easily grasped, and the observation time can be shortened.

As described above, according to the X-ray stereo fluoroscopic apparatus of the present invention and the stereo observation method using the same, the following advantageous effects can be obtained.
According to invention of Claim 1, it has the following effects.
(1) The X-ray excellent in practicality can rotate the subject by the angle setting mechanism, and can easily take a transmission image at an arbitrary angle of the subject by irradiating X-rays in a short time. A stereo fluoroscopic device can be provided.
(2) By providing a planar image sensor, distortion of a transmission image is hardly generated and stereo display reproducibility is excellent, and the distance between the X-ray source and the image sensor can be shortened to reduce the size of the apparatus. It is possible to provide an X-ray stereoscopy device that is excellent in space saving.

  According to invention of Claim 2, in addition to the effect of Claim 1, it has the following effects. (1) The tilting table can be rotated around two axes orthogonal to each other by the rotation holding unit, and the subject can be tilted three-dimensionally. Therefore, it is possible to provide an X-ray stereofluoroscope having excellent versatility and practicality.

According to invention of Claim 3, in addition to the effect of Claim 1 or 2, it has the following effects.
(1) A reflection mirror disposed between an X-ray source and a subject can reflect reflected light reflected from the surface of the subject, and a surface image of the subject can be taken with an optical camera. It is possible to provide an X-ray stereo fluoroscope having excellent practicality and versatility capable of observing the surface of a subject in addition to observation with a transmission image using a line.
(2) The subject is photographed with an optical camera having a focal point at a position optically equidistant from the X-ray source, so that the subject can be viewed at an angle of view almost equal to a transmission image by X-rays. Since the surface image can be obtained, the transparency of the transmission image and the surface image can be easily compared without special processing such as enlargement or reduction of the surface image. It is possible to provide an X-ray stereoscopy apparatus excellent in the above.

According to invention of Claim 4, in addition to the effect of Claim 3, it has the following effects.
(1) By superimposing and displaying the transmission image and the surface image, the three-dimensional structure of the subject can be expressed in a state where the inside of the real object is seen through, and the display performance is excellent, and a three-dimensional sense of distance is provided. Easy to grasp, can easily recognize the structure and arrangement of the subject, etc., and has excellent processing capability for observation that can detect the location of internal defects accurately and perform operations such as positioning in a short time An X-ray stereo fluoroscopic device can be provided.

According to invention of Claim 5, it has the following effects.
(1) In the detection angle setting step, the subject can be rotated to easily set the angle formed by the surface of the subject and the surface of the image sensor. In the transmission image detection step, at least two types of By irradiating the subject with X-rays at an angle, a planar image sensor can accurately detect at least two types of transmitted images of the subject in a short time and is a practical and reliable stereo observation method. Can be provided.
(2) In the stereo display process, the image processing time can be shortened by selecting two types of transmission images having different angles from the transmission images detected in the transmission image detection process and displaying them in stereo. Therefore, it is possible to provide a stereo observation method excellent in processing capability of inspection capable of accurately performing three-dimensional observation of the internal structure and internal defect of the subject at an arbitrary angle.

According to invention of Claim 6, in addition to the effect of Claim 5, it has the following effects.
(1) In the surface image capturing process, by using a reflection mirror disposed between the X-ray source and the subject, the surface image of the subject corresponding to the transmitted image can be accurately captured by the optical camera. A stereo observation method with excellent reliability and functionality can be provided.
(2) By disposing the optical camera so that the distance from the focal point of the optical camera used in the surface image capturing step to the subject is optically equidistant with the distance from the X-ray source to the subject, A surface image of a subject can be taken with an angle of view almost the same as a transmission image by X-ray, image processing such as superimposition of the transmission image and the surface image is easy, and data processing time is shortened. Therefore, it is possible to provide a stereo observation method with excellent practicality.

According to invention of Claim 7, in addition to the effect of Claim 6, it has the following effects.
(1) In the hybrid display step, the surface image corresponding to the transmission image of the subject is superimposed and displayed in stereo, so that the three-dimensional information of the subject can be recognized in a short time, and the observation time is shortened. Therefore, it is possible to provide a stereo observation method with excellent practicality.

Hereinafter, an X-ray stereo fluoroscope according to an embodiment of the present invention and a stereo observation method using the same will be described with reference to the drawings.
(Embodiment 1)
FIG. 1 is an overall perspective view showing an X-ray stereo fluoroscope according to Embodiment 1 of the present invention.
In FIG. 1, 1 is an X-ray stereo fluoroscopic apparatus according to the first embodiment, 2 is a shielding box that covers the apparatus main body of the X-ray fluoroscopic apparatus 1, 2a is an open / close door that is disposed in the shielding box 2 and allows a subject to be taken in and out. 2b is a window with X-ray shielding glass disposed in the shielding box 2, 3 is a control unit such as a personal computer for controlling the X-ray fluoroscopic apparatus 1, and 4 is connected to the control unit 3 and is connected to the transmission image of the subject. A display device such as a liquid crystal display that displays a surface image in stereo.

Next, the configuration of the X-ray stereo fluoroscope according to Embodiment 1 of the present invention will be described in detail.
FIG. 2 is a schematic front view showing a main part of the configuration of the X-ray stereo fluoroscopic apparatus according to Embodiment 1 of the present invention. FIG. 3 is a main part of the configuration of the X-ray stereo fluoroscopic apparatus according to Embodiment 1 of the present invention. It is a side surface schematic diagram.
2 and 3, reference numeral 5 denotes an X-ray source that emits X-rays, 6 denotes an angle setting mechanism of the X-ray fluoroscopic apparatus 1 that rotatably holds the subject 20, and 7 denotes a subject 20 that includes an XY stage 8. Is a tilting table of the angle setting mechanism 6, 8 a is a pivot shaft of the angle setting mechanism 6 connected in a horizontal plane of the tilt table 7, and 9 is connected to the pivot shaft 8 to move the tilt table 7 in the left-right direction. A rotation drive unit 10 of an angle setting mechanism 6 such as a pulse motor or a servo motor that is fixed to rotate at an arbitrary angle 10 is disposed opposite to the X-ray source 5 with the tilt table 7 interposed therebetween, and a subject 20 irradiated with X-rays. A CCD-type or CMOS-type planar image sensor 11 that detects a transmitted image of the object is disposed between the X-ray source 5 and the subject 20 and reflects the reflected light reflected from the surface of the subject 20. The mirror 12 has a distance to the subject 20 that is optical with the X-ray source 5. In an equidistant optical camera for capturing a surface image of the subject 20 is reflected by the reflecting mirror 11 has a focal point of the single focus lens 12a to the position.

  By covering the parts other than the control unit 3 and the display 4 with the shielding box 2, leakage of X-rays to the outside was prevented. The shielding box 2 is provided with an opening / closing door for taking in and out the subject (FIG. 1). Thereby, fixation of the subject 20 to the tilt table 7 and recovery of the subject 20 from the tilt table 7 can be easily performed. Further, X-ray shielding glass was disposed on the opening / closing door 2a and the window 2b of the shielding box 2. Thereby, it is possible to confirm the operation by directly looking at the movement of the tilting table 7 from the outside, and to prevent malfunction. In the present embodiment, the opening / closing door 2a is provided in front of the shielding box 2. However, the opening / closing doors may be provided on both the left and right sides of the shielding box. Thereby, since the subject 20 can be taken in and out from the left and right open / close doors, the operation can be automated by easily incorporating the X-ray fluoroscopic apparatus 1 into an inspection line or the like, and the efficiency is excellent.

The subject 20 was fixed on the XY stage 8 of the tilting table 7 by sticking with a double-sided tape. When the subject 20 is relatively large, the subject 20 may be fixed by being adsorbed by air or holding the outer shape of the subject 20.
Since the tilt table 7 includes the XY stage 8, the subject 20 can be moved back and forth and left and right within a plane parallel to the tilt table 7, and an arbitrary portion of the subject 20 is selected and observed in detail. be able to.
A rotation shaft 8a is disposed on the tilt table 7, and is disposed in parallel with the planar image sensor 10 in the initial state. Thereby, the transmission image of the subject 20 can be detected at an accurate angle when the tilting table 7 is rotated by the rotation driving unit 9. Further, since the entire subject 20 can be rotated on the X-ray source 5 side with respect to the rotation shaft 8a, the entire subject 20 is relatively closer to the front side of the screen of the display unit 4, that is, relatively when displayed in stereo. It can be displayed as a solid existing in the vicinity of the observer. As a result, the subject 20 can be easily recognized as a three-dimensional object and has excellent visibility, so that the occurrence position of the internal defect can be easily grasped, and an arbitrary position of the subject 20 can be easily indicated on the screen. Excellent.

As the image sensor 10, a CCD type or CMOS type formed in a planar shape was used. Thereby, distortion hardly occurs in the image, the entire X-ray fluoroscopic apparatus 1 can be downsized, and can be suitably used for observation of a minute object.
A reflection mirror 11 is disposed between the X-ray source 5 and the subject 20. Thereby, the reflected light reflected from the surface of the subject 20 can be reflected, and a surface image of the subject 20 can be taken. Since the X-rays emitted from the X-ray source 5 are transmitted through the reflection mirror 11, the reflection mirror 11 does not affect the capturing of a transmission image by X-rays.
A single focal lens 12a is used as the lens of the optical camera 12, and the distance from the X-ray source 5 to the subject 20 and the distance from the focal point of the single focal lens 12a to the subject 20 are optically equidistant. It was made to become. Since the single focal length lens 12a has a fixed focal length and a fixed shooting angle of view, there is no need to adjust the optical system at the time of shooting, and a surface image of the subject 20 is shot with a view angle almost equal to a transmission image by X-rays. can do. Moreover, a lens aberration is small and a high quality image can be obtained.
A zoom lens may be used in place of the single focus lens 12a. In this case, the focal length needs to be adjusted, and the lens aberration is larger than that of the single focus lens 12a. .

The control unit 3 can arbitrarily set the observation position and the imaging angle of the subject 20 by controlling the XY stage 8 and the rotation drive unit 9 of the angle setting mechanism 6. In addition, data such as transmission images, surface images, and observation conditions can be stored in various storage media such as a hard disk, MO, CD, and DVD disposed in the control unit 3. As a result, the stored data can be easily managed, and the data can be taken out and displayed on the display 4 as appropriate, or the image can be processed by image processing software or the like.
The display 4 displays two images with different imaging angles, thereby allowing the subject 20 to be recognized as a three-dimensional object based on the difference in imaging angles (imaging parallax).
The display device 4 may be any device that can display a planar image in stereo, such as an anaglyph stereoscopic display using red and blue glasses, a cross-method stereoscopic display or a parallel stereoscopic display using autostereoscopic viewing, or a screen. A display that can be switched and a combination of liquid crystal shutter glasses may be used. In particular, stereoscopic glasses do not require a large display, so the X-ray fluoroscopic apparatus 1 can be miniaturized, and are inexpensive and excellent in space saving.

A stereo observation method using the X-ray stereo fluoroscope according to the first embodiment formed as described above will be described.
FIG. 4 is a schematic side view of an essential part showing a stereo observation method using an X-ray stereo fluoroscope.
First, in the detection angle setting step, as shown in FIG. 4A, the tilt table 7 on which the subject 20 is fixed is rotated by the rotation drive unit 9 and fixed at the first angle θ1 (for example, 8 degrees). .
Next, in the transmission image detection step, the subject 20 is irradiated with X-rays from the X-ray source 5, and the planar image sensor 10 disposed so as to face the X-ray source 5 with the tilt table 7 interposed therebetween The first transmission image is detected and stored in the control unit 3 (see FIGS. 1 and 2).
Further, in the surface image capturing step, the first surface image of the subject 20 corresponding to the first transmission image is captured by the optical camera 12 and stored in the control unit 3.
Again, in the detection angle setting step, the tilt table 7 is rotated and fixed at the second angle θ2 (for example, 20 degrees) as shown in FIG. 4B, and in the transmission image detection step, the second of the subject 20 is detected. Is transmitted to the control unit 3 (see FIGS. 1 and 2).
In the surface image capturing process, a second surface image of the subject 20 corresponding to the second transmission image is captured and stored in the control unit 3.

Next, the stereo display process will be described. FIG. 5 is a schematic diagram showing a stereo display process.
In FIG. 5, 20a is the observation point of the subject 20, 25 is the observer, 25a and 25b are the left and right eyes of the observer 25, l is the distance from the display 4 to the observer 25, and w is the observer 25. An interval between the left and right eyes 25a and 25b, α is a difference in photographing angle (photographing parallax).
The first and second transmission images having different angles detected in the transmission image detection step are taken out from the control unit 3 and displayed in stereo on the display 4.
Here, α = 2tan ⁻¹ (w / 2l), and when l = 300 mm and w = 60 mm, α = 11.4 (degrees). Therefore, for example, by setting the first angle θ1 = 8 (degrees) and the second angle θ2 = 20 (degrees) as described above, α≈θ2−θ1 is obtained, and almost proper stereo display can be performed.
Since the stereo display can be performed using the first and second transmission images photographed at the two kinds of angles θ1 and θ2 set in the detection angle setting step, the internal structure and internal defects of the subject 20 can be accurately detected in a short time. Can be observed in three dimensions.
In the hybrid display step, the first and second surface images corresponding to the first and second transmission images are superimposed and displayed in stereo. Accordingly, the three-dimensional structure of the subject 20 can be expressed in a state where the inside of the real object is seen through, and the three-dimensional information of the subject 20 can be recognized in a short time, and the observation time can be shortened.

The rotation angle θ (see FIG. 1) of the tilt table 7 can be selected as appropriate. When the angle to be observed is known in advance, the two types of angles θ1 and θ2 are set as described above, and two types of transmission images and surface images necessary for stereo display are taken. . Further, after taking a large number of transmission images while changing the rotation angle θ little by little, it is also possible to perform observation by stereo display with a combination of arbitrary angles. The magnification in the depth (thickness) direction can be changed by the difference between the two types of angles θ1 and θ2. In particular, by increasing the angle difference between θ1 and θ2, it is possible to perform display that is enlarged and emphasized in the depth (thickness) direction.
Furthermore, when performing stereo display, when one of the two images is fixed and the other is continuously switched to an image with a different angle, it can be displayed while changing the viewing angle like a movie. it can. At this time, since the magnification in the depth (thickness) direction changes according to the viewing angle, it is possible to select an angle at which observation is easy while viewing the screen, and the observation workability is excellent.
In addition, when two images in stereo display are simultaneously switched and displayed at different angles, it is possible to perform observation while changing the viewpoint while rotating the entire subject 20. Thereby, observation from various angles can be performed continuously in a short time, and observation of the internal structure and internal defects of the subject 20 is easy and excellent in practicality.

Next, a modified example of the angle setting mechanism will be described.
FIG. 6 is a plan view of an essential part showing a modification of the angle setting mechanism.
In FIG. 6, 6 a is an angle setting mechanism showing a modification, 7 a is a rotation holding portion of the angle setting mechanism 6 a that rotatably holds the inclination table 7 around two axes orthogonal to each other, and 8 a ′ is the inclination table 7. The left and right rotation shafts 8b are formed in a substantially U shape and are arranged at both ends of the left and right rotation shaft 8a '. An arm portion 8c of the rotation holding portion 7a that is rotatably held, 8c is a front-rear direction rotation axis of the rotation holding portion 8b disposed on the arm portion 8b orthogonal to the left-right direction rotation shaft 8a ', 9a is It is a rotation drive unit of an angle setting mechanism 6a that is connected to the front-rear direction rotation shaft 8c and rotates the tilt table 7 in the front-rear direction via a rotation holding unit 8b.
Thereby, since the tilt table 7 on which the subject 20 is fixed can be rotated around two axes orthogonal to each other, the subject 20 can be tilted three-dimensionally, The observation angle can be arbitrarily set, and is excellent in versatility and practicality.

As described above, the X-ray stereoscopy apparatus according to Embodiment 1 is configured, and thus has the following operations.
(1) Since the angle setting mechanism 6 that rotatably holds the subject 20 is provided, the surface of the subject 20 and the surface of the image sensor 10 can be formed only by rotating the tilt table 7 by the angle setting mechanism 6. The angle can be easily set, and a transmission image at an arbitrary angle of the subject 20 can be easily taken by irradiating the X-ray from the X-ray source 5.
(2) Since the X-ray source 5 and the planar image sensor 10 are disposed opposite to each other with the subject 20 interposed therebetween, a transmission image of the subject 20 can be detected with high accuracy, and stereo display by the display 4 can be performed. Excellent reproducibility.
(3) By using the X-ray source 5, observation of the internal structure of the subject 20, internal defects, and the like can be reliably detected regardless of the size and shape of the subject 20, and the utility and versatility are excellent.
(4) Since the rotation axis 8a is disposed on the tilt table 7, the entire subject 20 can be rotated on the X-ray source 5 side with respect to the rotation axis 8a. The entire subject 20 can be displayed as a solid existing in front of the screen of the display 4, that is, relatively close to the observer 25, and the subject 20 can be easily recognized as a solid, and the position of occurrence of an internal defect can be accurately determined. It can be easily grasped and pointed on the screen.
(5) Since the tilt table 7 includes the XY stage 8, the subject 20 can be moved back and forth and left and right within a plane parallel to the tilt table 7, and an arbitrary portion of the subject 20 can be selected. It can be observed in detail.
(6) Since the image sensor 10 is formed in a planar shape, it is difficult for distortion to occur in the image, and the X-ray stereo fluoroscopic apparatus 1 can be easily miniaturized and is preferably used for observation of a minute object. it can.
(7) Since the reflection mirror 11 is provided between the X-ray source 5 and the subject 20 and reflects the reflected light reflected from the surface of the subject 20, the reflection mirror 11 is added to the transmission image by X-rays. The surface image of the subject 20 reflected by the optical camera 12 can be taken by the optical camera 12, and the surface of the subject 20 can be observed.
(8) By providing the optical camera 12 having a focal point at a position optically equidistant from the X-ray source 5 to the subject 20, the subject 20 has an angle of view substantially equal to that of a transmission image by X-rays. Since the surface image can be taken, it is not necessary to perform special image processing such as enlargement or reduction on the transmission image or the surface image, and the comparison is easy and the handling of the image data is excellent.
(9) When the single focus lens 12a having a fixed focal length and a fixed shooting angle of view is used as the lens of the optical camera 12, the optical system does not need to be adjusted at the time of shooting. Low aberration, high quality images can be taken, non-destructive inspection can be performed efficiently with high accuracy and excellent reliability.
(10) By superimposing and displaying the transmission image and the surface image, it is possible to express a state where the inside of the real object is seen through, and it is easy to grasp a three-dimensional sense of distance, and the structure and arrangement of the subject 20 are easy to grasp. Positioning and the like can be easily performed in an easy-to-understand manner.
(11) The angle setting mechanism 6a holds the tilt table 7 to which the subject 20 is fixed so as to be rotatable about two axes, a left-right direction rotation axis 8a ′ and a front-rear direction rotation axis 8c. Since the subject 20 can be tilted three-dimensionally by having the moving holding part 7a, the imaging angle and observation angle of the transmission image can be arbitrarily set, and the versatility and practicality are excellent.

According to the stereo observation method using the X-ray stereo fluoroscopic apparatus in the first embodiment, it has the following operations.
(12) By simply rotating the tilt table 7 to which the subject 20 is fixed by the rotation drive unit 9 in the detection angle setting step, the arbitrary rotation angle θ is easily selected and the subject 20 is fixed. be able to.
(13) Through the transmission image detection step, the subject 20 can be irradiated with X-rays from the X-ray source 5 at at least two types of angles θ1 and θ2 set in the detection angle setting step. At least two types of transmission images of the subject 20 can be detected by the planar image sensor 10 disposed opposite to the X-ray source 5.
(14) By the stereo display process, two types of transmission images with different angles can be selected from the transmission images detected in the transmission image detection process and displayed in stereo on the display unit 4, and the subject can be accurately displayed in a short time. The internal structure of 20 and the state and position of internal defects can be observed three-dimensionally.
(15) The reflected light reflected from the surface of the subject 20 is reflected by the reflection mirror 11 disposed between the X-ray source 5 and the subject 20 in the surface image capturing step, and the subject corresponding to the transmission image is reflected. The surface image of the specimen 20 can be accurately captured by the optical camera 12.
(16) The optical camera 12 is arranged so that the distance from the focal point of the optical camera 12 used in the surface image capturing process to the subject 20 is optically equidistant with the distance from the X-ray source 5 to the subject 20. Since the surface image of the subject 20 taken with an angle of view almost the same as the X-ray transmission image can be obtained, the transmission image and the surface image can be overlapped without performing complicated image processing or the like. Processing such as combining can be performed, and the data processing time can be shortened.
(17) The surface of the subject 20 can be displayed in stereo by superimposing surface images corresponding to two types of transmission images of the subject 20 taken at different angles θ1 and θ2 by the hybrid display step. The shape and internal state can be displayed simultaneously, the three-dimensional structure of the subject 20 can be easily grasped, and the observation time can be shortened.
(18) When the angle at which observation is desired is known, two kinds of angles θ1 and θ2 can be set, and only two transmission images necessary for stereo display can be taken at a short time. Stereo observation can be performed with.
(19) After taking a large number of transmission images while changing the rotation angle θ of the tilting table 7 little by little, stereo observation can be performed at various angles by combining arbitrary angles for versatility and practicality. Excellent.
(20) When stereo display is performed, when one of the two images is fixed and the other is continuously switched to an image having a different angle, the stereo display is performed while changing the viewing angle like a moving image. be able to. Since the magnification in the depth direction changes according to the viewing angle, it is possible to select an angle at which observation is easy while viewing the screen, and the observation workability is excellent.
(21) When two images in stereo display are continuously switched and displayed at different angles, the observation can be performed while changing the viewpoint while rotating the entire subject 20, and the inside of the subject can be observed. Observation of structure and internal defects is easy and excellent in practicality.

  The present invention relates to an X-ray stereo fluoroscope for stereoscopic viewing of a subject in a non-destructive inspection or the like, and a stereo observation method using the same, and the observation of internal structures and internal defects regardless of the size and shape of the subject. Providing an X-ray stereo fluoroscope that is capable of detection and can be miniaturized with a simple structure that rotates the subject, and that is excellent in handling properties and accurate image processing in a short time using the same. 3D information can be obtained easily and easily, and a stereo observation method with excellent practicality can be provided, and can be suitably used especially for industrial applications where the observation object is minute. It is possible to realize a short-time inspection in a mass production line such as a factory.

1 is an overall perspective view showing an X-ray stereoscopy device in Embodiment 1 of the present invention. 1 is a schematic front view of a main part showing the configuration of an X-ray stereo fluoroscopic apparatus according to Embodiment 1 of the present invention. 1 is a schematic side view of a main part showing the configuration of an X-ray stereo fluoroscopic apparatus according to Embodiment 1 of the present invention. Schematic side view of relevant parts showing a stereo observation method using an X-ray stereo fluoroscope Schematic diagram showing the stereo display process The principal part top view which shows the modification of an angle setting mechanism

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 X-ray stereoscopic apparatus 2 Shielding box 2a Opening / closing door 2b Window 3 Control part 4 Indicator 5 X-ray source 6,6a Angle setting mechanism 7 Inclination table 7a Rotation holding part 8 XY stage 8a Rotation axis 8a 'Left-right direction rotation Moving shaft 8b Arm portion 8c Front / rear direction rotating shaft 9, 9a Rotation driving portion 10 Image sensor 11 Reflecting mirror 12 Optical camera 12a Single focus lens 20 Subject 20a Observation point 25 Observer 25a, 25b Eye

Claims (7)

  An X-ray source, an angle setting mechanism that rotatably holds the subject, a planar image sensor that is disposed to face the X-ray source across the subject and detects a transmission image of the subject, An X-ray stereo fluoroscopic apparatus, comprising: a display for stereo-displaying the transmission image detected by an image sensor.   The angle setting mechanism includes an inclination table to which the subject is fixed, and a rotation holding portion that rotatably holds the inclination table around two axes orthogonal to each other. The X-ray stereofluoroscopic apparatus according to 1.   A reflection mirror disposed between the X-ray source and the subject and reflecting reflected light reflected from the surface of the subject, and a distance to the subject is optically equidistant from the X-ray source The X-ray stereo fluoroscopic apparatus according to claim 1, further comprising: an optical camera that has a focal point at a position and takes a surface image of the subject reflected by the reflecting mirror.   The X-ray stereo fluoroscopic apparatus according to claim 3, wherein the display unit displays the transmission image and the surface image in an overlapping manner.   A detection angle setting step of setting the angle formed by the surface of the subject and the surface of the image sensor by rotating the subject by an angle setting mechanism in which the subject is rotatably held, and the detection angle setting step At least two of the subjects are irradiated with X-rays from the X-ray source at at least two kinds of angles set in (1) above and the planar image sensor is disposed opposite to the X-ray source with the subject interposed therebetween. A transmission image detection step for detecting transmission images of various angles, and a stereo display for selecting two types of transmission images at different angles from the transmission images detected in the transmission image detection step and displaying them in stereo on a display A stereo observation method comprising the steps of:   Reflected light reflected from the surface of the subject is reflected by a reflecting mirror disposed between the X-ray source and the subject, and the distance to the subject is optically equal to the X-ray source. 6. The stereo observation method according to claim 5, further comprising a surface image photographing step of photographing a surface image corresponding to a transmission image of the subject by an optical camera having a focal point at a distance position. The stereo observation method according to claim 6, further comprising a hybrid display step in which the transmission image of the subject and the surface image corresponding to the subject are superimposed and displayed in stereo on the display.

Images