JPH09131411A - Tubus for x-ray irradiation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain reproducibility during the loading or unloading along with highly accurate irradiation. SOLUTION: In this tubus for X-ray irradiation which has blocks 6 for drawing X rays, a cylinder 7 for supporting the block 6, a guide part 9 for inserting the cylinder 7 into a slit part 11 of a radiating therapeutic apparatus 1, a keep metalware mechanism 15 is provided to eliminate a clearance necessary for mounting the slip 11 of the radiation therapeutic apparatus 1 and the guide part 9 after the mounting thereof.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray irradiation tube for use in X-ray treatment in a medical linac.

[0002]

2. Description of the Related Art FIG. 9 is an overall view of a conventional radiation irradiation apparatus,
FIG. 10 shows, for example, VOL. 48
NO. 2 is a conventional tube for X-ray irradiation shown in FIG.
In the figure, reference numeral 1 is a main body of a radiation irradiation device for irradiating X-rays
1a is a target where X-rays are generated, 1b is irradiated radiation, 2 is radiation irradiated from the main body 1b
X-ray irradiating tube for narrowing down, 3 is radiation 1b
Is the center of rotation when rotating and irradiating 4
Is a patient to be treated, 5 is a treatment table on which the patient sits, 6 is a block for narrowing down the radiation 1b mounted in the tube 2, 6a is a hole provided in the block 6, 7 is for supporting the block 6 Tube, 8 is a pin for keeping the block 6 in a fixed position, 9 is a guide portion for inserting the tube 7 into the radiation irradiation apparatus 1, 10 is a pin for keeping the guide portion 9 in a fixed position, and 11 is a guide. A slit attached to the irradiation device main body 1 for inserting the portion 9, and a cylinder 7
The block 6 supported by is prevented from falling in the direction of the patient 4, and 13 is an obstacle to some obstacles.
A collision switch for urgently stopping irradiation and driving when the X-ray irradiation tube 2 collides, and 14 is a clearance (distance) between the isocenter 3 and the X-ray irradiation tube 2.
It is.

Next, the operation will be described. First, before the treatment, a block 6 having a block hole 6a matching the size of the tumor or the like of the patient 4 is inserted into the cylinder 7 from above and set in place with a pin 8. Block 6 is slip-out prevention 1
Since it is stopped by 2, there is no downward drop. The guide portion 9 of the X-ray irradiation two-tube 2 in which the block 6 is set is provided with the slit 1 attached to the irradiation apparatus main body 1.
Insert into 1 and position with pin 10. At this time, the position of the pin 10 and the position of the block 6 are set in advance so that the direction of the block hole 6a is exactly the direction of the isocenter 3. The radiation 1b generated from the target 1a of the X-ray irradiator main body 1 is focused on the beam by the block 6 supported by the tube 7, and passes through the block hole 6a to reach the isocenter position 3 of the patient 4 on the treatment table 5. Is irradiated.
When the shape of the affected part of the patient 4 is changed, the X-ray irradiating tube 2 is removed from the irradiation apparatus main body 1 and replaced with a block 6 having a hole 6a corresponding to the size of the affected part for treatment.
When any obstacle interferes with the collision switch 13 during the treatment, the generation of radiation, the driving of the irradiation unit main body, etc. are stopped urgently. Needless to say, the original function does not change even if the collision switch 13 is not attached to the X-ray irradiation tube 2.

[0004]

In the conventional apparatus, since the guide portion 9 and the slit portion 11 have a backlash when mounted on the irradiation apparatus main body 1, high-precision irradiation cannot be performed (if the backlash is eliminated, insertion becomes difficult). . Further, since the clearance 14 between the X-ray irradiating tube 2 and the isocenter 3 is short, the X-ray irradiating tube 2 interferes with the treatment depending on the patient's physique, the position of the affected area, and the like, so that treatment cannot be performed in some places. Further, when the processing and assembling accuracy of each part is poor, it is considered that the direction of the block hole 6a does not accurately point to the isocenter 3, leading to a decrease in accuracy, and it is also confirmed whether or not the isocenter 3 is accurately pointed. Have difficulty. In addition, in order to replace the block 6, the X-ray irradiation tube 2 has to be removed from the irradiation apparatus main body 1 one by one. Further, when the accuracy of the irradiation apparatus body 1 itself is not maintained (often, the irradiation using the X-ray irradiation tube is required to have higher accuracy than general treatment), the X-ray irradiation tube 2 is naturally used.
There was a problem that the accuracy could not be improved by.

The present invention has been made in order to solve the above-mentioned problems, and eliminates the play of mounting the X-ray irradiating tubs to allow a large clearance between the X-ray irradiating tubs and the isocenter. Blocks can be replaced without removing the beam irradiation tube from the main body,
An object of the present invention is to provide an X-ray irradiation tube which is provided with a fine adjustment mechanism for accuracy adjustment, can perform accuracy confirmation easily and accurately, and can improve irradiation accuracy more than in general treatment.

[0006]

According to a first aspect of the present invention, there is provided a tube for irradiating X-rays, a block for narrowing X-rays, a tube for supporting the block, and the tube being inserted into a slit of a radiotherapy apparatus. In the X-ray irradiation tube having a guide portion for holding, a holding metal member mechanism for eliminating a gap required for mounting the slit of the radiotherapy apparatus and the guide portion after mounting is provided.

According to another aspect of the present invention, there is provided a X-ray irradiating tube including a block for narrowing X-rays, a cylinder for supporting the block, and a guide portion for inserting the cylinder into a slit of a radiotherapy apparatus. The X-ray irradiating tube has a block having a small specific gravity.

According to another aspect of the present invention, there is provided a tube for irradiating X-rays, which comprises a block for narrowing down X-rays, a tube for supporting the block, and a guide portion for inserting the tube into a slit of a radiotherapy apparatus. The X-ray irradiating tube has a tilting mechanism in the cylinder so that the block can be replaced without removing it from the radiation therapy apparatus.

According to another aspect of the present invention, there is provided an X-ray irradiating tube including a block for narrowing down X-rays, a cylinder for supporting the block, and a guide portion for inserting the cylinder into a slit of a radiotherapy apparatus. In the X-ray irradiation tube, the X-ray irradiation tube is provided with a fine adjustment mechanism in the cylinder.

According to another aspect of the present invention, there is provided a X-ray irradiating tube including a block for narrowing X-rays, a cylinder for supporting the block, and a guide portion for inserting the cylinder into a slit of a radiotherapy apparatus. The X-ray irradiation tube has a CCD camera attached to a hole for narrowing X-rays of the block, and an image processing device for processing an image captured by the CCD camera.

According to another aspect of the present invention, there is provided a X-ray irradiating tube including a block for narrowing X-rays, a cylinder for supporting the block, and a guide portion for inserting the cylinder into a slit of a radiotherapy apparatus. The X-ray irradiation tube has a CCD camera mounted outside the block, a mirror for aligning the camera irradiation field with the beam axis, and an image processing device for processing an image captured by the CCD camera. And

According to another aspect of the present invention, there is provided an X-ray irradiating tube including a block for narrowing down X-rays, a cylinder for supporting the block, and a guide portion for inserting the cylinder into a slit of a radiotherapy apparatus. In the X-ray irradiation tube that the user has, a fine adjustment mechanism provided on the cylinder, a drive mechanism for driving the fine adjustment mechanism, and accuracy data measured for each arbitrary posture of each radiotherapy apparatus are held in advance. A data table, a position detection mechanism that detects the position of the radiation therapy apparatus with respect to the posture, and an accuracy error amount at that position is extracted from the data table in accordance with the data from this position detection mechanism, and correction is made in accordance with the size. And a control device that controls the drive mechanism.

According to another aspect of the present invention, there is provided a X-ray irradiating tube including a block for narrowing X-rays, a cylinder for supporting the block, and a guide portion for inserting the cylinder into a slit of a radiotherapy apparatus. In the X-ray irradiation tube that the user has, a fine adjustment mechanism provided in the cylinder, a drive mechanism for driving the fine adjustment mechanism, and a CCD mounted outside the block
Based on the camera, the mirror for adjusting the camera irradiation field to the beam axis, the image processing device for processing the image captured by the CCD camera and capturing the accuracy data, and the accuracy data,
An X-ray irradiating tube comprising a calculation device for calculating the adjustment amount of the cylinder and a control device for driving the drive mechanism based on the calculation result of the calculation device.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. Embodiment 1 of the present invention will be described below with reference to the drawings. FIG. 1 shows X according to Embodiment 1 of the present invention.
FIG. 3 is a plan view and a side view of a line irradiation tube. In the figure, reference numerals 1 to 14 are exactly the same as those of the conventional device, and the description thereof will be omitted. Reference numeral 15 is a pressing metal fitting for pressing the guide portion 9 in one direction, and 16 is a holding screw for pressing the pressing metal fitting 15.

Next, the operation will be described. The X-ray irradiating tube 2 is mounted by sliding the guide portion 9 into the slit 11 of the irradiating apparatus main body 1 as in the conventional apparatus, and is positioned by the pin 10. At this time, since there is some clearance between the slit 11 and the guide portion 9, backlash occurs in the X-ray irradiation two-tubs 2 (it is difficult to mount without the clearance), but by tightening the cap screw 16. The pressing metal fitting 15 presses the guide portion 9 in any direction of the slit 11 to eliminate looseness between the X-ray irradiation two-tub 2 and the radiation irradiation apparatus 1 and improve irradiation accuracy. Further, even when the X-ray irradiating tube 2 is detached from the radiation irradiating device 1 when the block is replaced, the reproducibility of accuracy is ensured because it is pressed in the same direction when reattaching.

Embodiment 2 Hereinafter, a second embodiment of the present invention will be described with reference to the drawings. 2 is a plan view and a side view of an X-ray irradiating tube according to Embodiment 2 of the present invention. In the figure, 6A is a block manufactured using a material having a higher specific gravity than the block 6 of FIG.

Next, the operation will be described. Although the basic operation is the same as the conventional method, the size of the block itself can be reduced by replacing the block 6 with the block 6A made of a material having a higher specific gravity. As a material having a large specific gravity, for example, lead (specific gravity 11.
3) or heavy metal (specific gravity 17) is used. This is because the ability of the block to shield the radiation 1b is proportional to the weight of the shielding material, so that the tube 7 can be downsized with the downsizing of the block, and the entire X-ray irradiation tube 2 can be downsized.
By doing so, the clearance 14 between the X-ray irradiating tube 2 and the isocenter 3 can be widened, so that the treatment can be performed without being influenced by the physique of the patient 4 and the position of the affected part 4.

Embodiment 3. Hereinafter, a third embodiment of the present invention will be described with reference to the drawings. 3 is a plan view and a side view of an X-ray irradiating tube according to a third embodiment of the present invention. In the figure, 17 is a rotary shaft that tilts the cylinder 7 that supports the block 6, 18 is a fixing pin that fixes the cylinder 7 to the guide portion 9, and 19 is a stopper that prevents the tilted cylinder 7 from tilting more than necessary. Is.

Next, the operation will be described. The cylinder 7 supporting the block 6 is tilted to the stopper 19 about the rotary shaft 17 by releasing the fixing pin 18.
By tilting the cylinder 7 to some extent, the block 6 can be replaced with a different type without removing the X-ray irradiation tube 2 from the radiation irradiation apparatus 1, so that the block replacement work can be performed efficiently and the X-ray irradiation can be performed. The error that occurs when the irradiation tube 2 is removed can be repaired, and irradiation with higher accuracy becomes possible.

Embodiment 4 Hereinafter, a fourth embodiment of the present invention will be described with reference to the drawings. 4 is a plan view and a side view of an X-ray irradiating tube according to Embodiment 4 of the present invention. In the figure, 20 is an XY stage, 21 is a spring mechanism that connects the guide portion 9 and the XY stage 20 with a preload, 22 is a spring mechanism that connects the cylinder 7 and the XY stage 20 with a preload, and 23 is an XY stage. The direction fine adjustment screw 24 is a tilt direction fine adjustment screw.

Next, the operation will be described. By operating the XY direction fine adjustment screw 23 in any direction, the XY stage 20 can be adjusted in the XY direction while the spring mechanism 21 is pulled or compressed. Similarly, by operating the tilt direction fine adjustment screw 24 in any direction, the spring mechanism 22 is pulled and compressed, and the tilt direction of the cylinder 7 can be adjusted. By using these adjustment mechanisms, even if the direction of the block hole 6a and the position of the isocenter 3 are deviated for some reason, the deviation can be corrected and more accurate irradiation can be performed. Become. Incidentally, in the present embodiment, the device capable of adjusting both the XY direction and the tilt direction has been described, but the adjustment can be made with only one of them, and the function changes even if the direction, quantity, etc. of the fine adjustment screws are changed. It goes without saying that there is no such thing.

Embodiment 5. Hereinafter, a fifth embodiment of the present invention will be described with reference to the drawings. 5 is a plan view and a side view of an X-ray irradiating tube according to a fifth embodiment of the present invention. In the figure, 25 is a CCD camera attached to the block hole 6a, and 26 is an image processing device (including peripheral devices such as a camera controller and a monitor) for processing an image captured by the CCD camera 25.

Next, the operation will be described. Block hole 6
The CCD camera 25, which is attached to a so that the direction of the hole and the direction of the camera coincide with each other, captures an image of a region irradiated with radiation and sends it to the image processing device 26 online. By obtaining the position coordinates of the isocenter image with respect to an arbitrary posture of the radiation irradiation device 1 in the image processing device 26, it is possible to easily and accurately measure the irradiation accuracy.

Embodiment 6 FIG. Hereinafter, a fifth embodiment of the present invention will be described with reference to the drawings. 6 is a plan view and a side view of an X-ray irradiating tube according to a sixth embodiment of the present invention. In the figure, 25A is a CCD camera provided outside the block 6, and 27 is a polarizing mirror for aligning the image of the CCD camera 25A with the axis of the radiation 1b.

Next, the operation will be described. The CCD camera 25A captures the image reflected by the polarizing mirror 27 in the same direction as the radiation axis and sends it to the image processing device 26. The accuracy is measured by obtaining the position coordinates of the isocenter image with respect to an arbitrary posture of the radiation irradiation device 1 in the image processing device 26. CCD camera 25A at this time
Since the image captured by is the same as the trajectory of the radiation 1b, more accurate accuracy measurement can be performed. Moreover, since the CCD camera 25A is positioned so as not to interfere with irradiation, the accuracy can be measured in real time even during irradiation (radiation 1
b can pass through the mirror). Although the CCD camera 25A and the polarizing mirror 27 are installed on the side of the radiation irradiating device 1 in the present embodiment, the same effect can be obtained by installing the CCD camera 25A and the polarizing mirror 27 inside the X-ray irradiating tube (upper side of the block).

Embodiment 7 Hereinafter, a seventh embodiment of the present invention will be described with reference to the drawings. FIG. 7 is a plan view and a side view of an X-ray irradiating tube according to a seventh embodiment of the present invention. In the figure, 28 is an XY direction drive device for automatically driving the fine adjustment screw of the XY direction fine adjustment mechanism shown in the fourth embodiment, and similarly 29 is a tilt for automatically driving the fine adjustment screw of the tilt direction fine adjustment mechanism. Directional driving device, 30 is a control device for controlling the driving devices 28 and 29, and 31 is the accuracy for each posture measured (Embodiment 5 or 6 or another method) for each radiation irradiation device. The data table 32 is a position detection mechanism that detects the position of the radiation irradiation apparatus 1 with respect to the posture.

Next, the operation will be described. Data of accuracy measured by the fifth or sixth embodiment or another method for each arbitrary posture of each radiation irradiation apparatus is held in advance as a data table 31 (data table for each radiation irradiation apparatus). The precision error amount at that position is extracted from the data table 31 in accordance with the data from the radiation irradiation device position detection mechanism 32, and the control device 30 makes corrections to the drive devices 28 and 29 according to the size. Conventionally, the radiation irradiation apparatus has been unable to eliminate the irradiation error because it bends or twists depending on the rotation angle, but this apparatus can improve the accuracy.

Embodiment 8 Embodiment 8 of the present invention will be described below with reference to the drawings. FIG. 8 is a plan view and a side view of an X-ray irradiating tube according to an eighth embodiment of the present invention. In the figure, reference numeral 33 is an arithmetic device for calculating a fine adjustment amount at high speed based on the data processed by the image processing device 26 of the isocenter image captured by the CCD camera 25A.

Next, the operation will be described. Embodiment 6
Based on the accuracy data taken in while performing image processing in real time by the method similar to the method described in (1), the arithmetic unit 33 calculates the adjustment amount of the X-ray irradiation tube, and sends the calculation result to the control unit 30. By driving the driving devices 28 and 29, real-time accuracy control can be performed while performing irradiation. By providing the high-speed image processing device and the arithmetic device, feedback control is performed, and more accurate irradiation becomes possible.

[0030]

According to the X-ray irradiating tube of claim 1, a block for narrowing X-rays, a cylinder for supporting the block, and a guide portion for inserting the cylinder into the slit of the radiotherapy apparatus. In the X-ray irradiation tube having the above, since the gap required for mounting the slit of the radiotherapy device and the guide portion is provided with a holding metal mechanism for eliminating after mounting, it is possible to perform highly accurate irradiation. , Reproducibility at the time of putting on and taking off can be maintained.

The X-ray irradiation tube of claim 2 comprises a block for narrowing X-rays, a cylinder for supporting the block, and a guide portion for inserting the cylinder into the slit of the radiotherapy apparatus. In the X-ray irradiating tube that we have, the block has been made a small one with a large specific gravity.
The clearance between the radiation irradiation tube and the isocenter can be widened, and treatment can be performed regardless of the size or position of the patient.

The X-ray irradiation tube of claim 3 comprises a block for narrowing X-rays, a tube for supporting the block, and a guide portion for inserting the tube into the slit of the radiotherapy apparatus. In the X-ray irradiating tube that is provided, since the tilt mechanism is provided in the cylinder so that the block can be replaced without removing it from the radiotherapy apparatus, the workability of the block replacement is improved and the irradiation accuracy generated during the block replacement is improved. It can prevent the deterioration.

According to another aspect of the present invention, there is provided a tube for X-ray irradiation comprising a block for narrowing down X-rays, a tube for supporting the block, and a guide portion for inserting the tube into a slit of a radiotherapy apparatus. In the X-ray irradiating tube that is provided, since the fine adjustment mechanism is provided in the cylinder, highly accurate irradiation can be performed.

According to another aspect of the present invention, there is provided an X-ray irradiating tube including a block for narrowing X-rays, a cylinder for supporting the block, and a guide portion for inserting the cylinder into a slit of a radiotherapy apparatus. Since the X-ray irradiation tube has the CCD camera installed in the hole for narrowing the X-rays of the block and the image processing device for processing the image captured by the CCD camera, it is easy and accurate. The accuracy of irradiance can be confirmed.

According to another aspect of the present invention, there is provided an X-ray irradiating tube including a block for narrowing X-rays, a tube for supporting the block, and a guide portion for inserting the tube into a slit of a radiotherapy apparatus. The X-ray irradiation tube has a CCD camera mounted outside the block, a mirror for adjusting the camera irradiation field to the beam axis, and an image processing device for processing the image captured by the CCD camera. So, visually see the part where the radiation hits,
In addition, since the beam axis can be captured in real time because the camera is not blocked, the accuracy of radiation irradiation can be confirmed more accurately.

The X-ray irradiation tube of claim 7 comprises a block for narrowing X-rays, a cylinder for supporting the block, and a guide portion for inserting the cylinder into the slit of the radiotherapy apparatus. In the X-ray irradiation tube that the user has, a fine adjustment mechanism provided on the cylinder, a drive mechanism for driving the fine adjustment mechanism, and accuracy data measured for each arbitrary posture of each radiotherapy apparatus are held in advance. A data table, a position detection mechanism that detects the position of the radiation therapy apparatus with respect to the posture, and an accuracy error amount at that position is extracted from the data table in accordance with the data from this position detection mechanism, and correction is made in accordance with the size. Since the control device for the drive mechanism is provided, it is possible to perform highly accurate irradiation independent of the accuracy of the irradiation device body.

According to another aspect of the present invention, there is provided a tube for irradiating X-rays, which comprises a block for narrowing down X-rays, a tube for supporting the block, and a guide portion for inserting the tube into a slit of a radiotherapy apparatus. In the X-ray irradiation tube that the user has, a fine adjustment mechanism provided in the cylinder, a drive mechanism for driving the fine adjustment mechanism, and a CCD mounted outside the block
Based on the camera, the mirror for adjusting the camera irradiation field to the beam axis, the image processing device for processing the image captured by the CCD camera and capturing the accuracy data, and the accuracy data,
Irradiation with higher accuracy that does not depend on the accuracy of the irradiation device main body because it is configured to include a calculation device that calculates the adjustment amount of the cylinder and a control device that drives the drive mechanism based on the calculation result of this calculation device. It can be performed.

[Brief description of the drawings]

FIG. 1 is a plan view and a side view of an X-ray irradiating tube according to a first embodiment of the present invention.

FIG. 2 is a plan view and a side view of an X-ray irradiation tube according to a second embodiment of the present invention.

FIG. 3 is a plan view and a side view of an X-ray irradiating tube according to a third embodiment of the present invention.

FIG. 4 is a plan view and a side view of an X-ray irradiating tube according to a fourth embodiment of the present invention.

FIG. 5 is a plan view and a side view of an X-ray irradiating tube according to a fifth embodiment of the present invention.

FIG. 6 is a plan view and a side view of an X-ray irradiating tube according to a sixth embodiment of the present invention.

FIG. 7 is a plan view and a side view of an X-ray irradiating tube according to a seventh embodiment of the present invention.

FIG. 8 is a plan view and a side view of an X-ray irradiation tube according to an eighth embodiment of the present invention.

FIG. 9 is a side view showing a state in which an X-ray irradiation tube is attached to a conventional radiation irradiation apparatus.

FIG. 10 is a plan view and a side view of a conventional X-ray irradiation tube.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Radiotherapy device, 2 X-ray irradiation tubs, 3 Isocenter, 4 Patients, 6 blocks, 6A blocks, 7 cylinders, 9 guide parts, 11 slits, 14 clearances, 15 retainer fittings, 16 retainer screws, 17
Rotating shaft, 18 fixing pin, 19 stopper, 20 XY
Stage, 21, 22 Spring mechanism, 23 XY direction fine adjustment screw, 24 Tilt direction fine adjustment screw, 25 CCD camera,
25 ACCD camera, 26 image processing device, 27 deflecting mirror, 28 XY direction driving device, 29 tilt direction driving device, 30 control device, 31 data table, 32 position detection mechanism, 33 arithmetic device.

Claims (8)

[Claims] 1. A X-ray irradiation tube having a block for narrowing X-rays, a cylinder for supporting the block, and a guide portion for inserting the cylinder into a slit of a radiotherapy apparatus. An X-ray irradiating tube comprising a holding metal fitting mechanism for eliminating a gap required for mounting the slit of the radiotherapy apparatus and the guide portion after mounting. 2. A tube for X-ray irradiation comprising a block for narrowing down X-rays, a tube for supporting the block, and a guide portion for inserting the tube into a slit of a radiotherapy apparatus. The X-ray irradiation tube is characterized by a small block with a large specific gravity. 3. An X-ray irradiation tube having a block for narrowing X-rays, a cylinder for supporting the block, and a guide portion for inserting the cylinder into a slit of a radiotherapy apparatus. The cylinder has a tilt mechanism,
The tube for X-ray irradiation, wherein the block can be replaced without removing it from the radiotherapy apparatus. 4. An X-ray irradiation tube having a block for narrowing down X-rays, a cylinder for supporting the block, and a guide portion for inserting the cylinder into a slit of a radiotherapy apparatus. A tube for X-ray irradiation, characterized in that the cylinder is provided with a fine adjustment mechanism. 5. A tube for X-ray irradiation, comprising: a block for narrowing down X-rays, a cylinder for supporting the block, and a guide portion for inserting the cylinder into a slit of a radiotherapy apparatus. An X-ray irradiation tube comprising a CCD camera attached to a hole for narrowing X-rays of a block and an image processing device for processing an image captured by the CCD camera. 6. A tube for X-ray irradiation, comprising: a block for narrowing down X-rays, a tube for supporting the block, and a guide portion for inserting the tube into a slit of a radiotherapy apparatus. A X-ray irradiation tube including a CCD camera attached to the outside of the block, a mirror for aligning the camera irradiation field with the beam axis, and an image processing device for processing an image captured by the CCD camera. . 7. A tube for X-ray irradiation, comprising: a block for narrowing down X-rays, a cylinder for supporting the block, and a guide portion for inserting the cylinder into a slit of a radiotherapy apparatus. A fine adjustment mechanism provided in the cylinder, a drive mechanism for driving the fine adjustment mechanism, a data table that holds in advance data of accuracy measured for each arbitrary posture of each radiation therapy apparatus, and the radiation therapy apparatus Position detection mechanism for detecting the position with respect to the posture of the device, and the precision error amount at that position is extracted from the data table in accordance with the data from the position detection mechanism, and the drive mechanism is corrected according to the size. A tube for X-ray irradiation, which is provided with a control device. 8. An X-ray irradiation tube having a block for narrowing down X-rays, a cylinder for supporting the block, and a guide portion for inserting the cylinder into a slit of a radiotherapy apparatus. A fine adjustment mechanism provided on the cylinder, a drive mechanism for driving this fine adjustment mechanism, a CCD camera mounted outside the block, a mirror for aligning the camera irradiation field with the beam axis, and the CCD camera An image processing device that processes an image and captures accuracy data, an arithmetic device that calculates the adjustment amount of the cylinder based on the accuracy data, and a control that drives the drive mechanism based on the arithmetic result of the arithmetic device. An X-ray irradiation tube that is equipped with a device.