JP2006325978A - Panorama roentgenography device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a panorama roentgenography device capable of photographing a photographing image with a small blur regardless of the shape of a tooth row. <P>SOLUTION: The device has an X-ray irradiating section 1 irradiating the tooth row of a patient with X rays and a photographing section 2 receiving the X ray having transmitted through a subject in each end portion, a rotatedly moving rotary arm 3, a distance measuring section 8 arranged in the rotary arm in the vicinity of the photographing section and measuring the distance between the region to be photographed and the X-ray irradiating section by irradiating the photographing region with laser beams and receiving the reflected laser beam, and a controlling section for rotating and moving the rotary arm such that the path of the rotary arm around a rotary center travels along the tooth row, the focus of the X rays corresponds to the rotary center point of the rotary arm. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a panoramic X-ray imaging apparatus used in a medical field such as dentistry.

  A generally used panoramic X-ray imaging apparatus will be described with reference to FIGS. 3 and 4 (see, for example, Patent Document 1). FIG. 3 is a perspective view showing a configuration of a conventional panoramic X-ray imaging apparatus. The rotary arm 103 is an arm having the X-ray irradiation unit 101 and the imaging unit 102 attached to each end. The X-ray irradiation unit 101 irradiates the patient's jaw with X-rays. The imaging unit 102 includes a film or a semiconductor imaging device that receives X-rays transmitted through the patient's jaw. The control unit 104 is a control circuit that controls the movement of the rotary arm 103 and performs rotation control in the direction of the arrow 5 and movement control in the directions of the arrows 6 and 7.

  Next, the operation of this panoramic X-ray imaging apparatus will be described. First, the rotating arm 103 is arranged so that the X-ray irradiation unit 101 and the imaging unit 102 face each other with the jaw portion of the patient as an imaging part interposed therebetween. FIG. 4 is a layout diagram showing the X-ray irradiation unit 101, the imaging unit 102, and the dentition of the imaging region. The standard shape 111 is a line indicating a preset standard dentition shape. The rotation center 112 is a center when the X-ray irradiation unit 101 and the imaging unit 102 rotate. The X-ray irradiation unit 101 and the imaging unit 102 (rotating arm 103) take an image of each imaging region by rotating and rotating the rotation center 112 on the dentition shape.

By using such a panoramic X-ray imaging apparatus, it is possible to perform imaging while emphasizing a cross-sectional portion of the dentition, which is an original imaging region, with respect to a region such as a skull or a cervical vertebra that is an obstacle to imaging.
Japanese Patent Laid-Open No. 8-257025

  However, since the actual dentition is slightly different for each patient, the image is based on the standard dentition trajectory set in advance. It is difficult to project a clear image at the same time.

  The present invention has been made to solve the above-described conventional problems, and an object thereof is to provide a panoramic X-ray imaging apparatus capable of capturing a captured image with small blur regardless of the shape of the dentition.

  In order to achieve the above object, a panoramic X-ray imaging apparatus of the present invention includes an X-ray irradiation unit that irradiates a subject with X-rays, and an imaging unit that detects X-rays transmitted through the subject at each end. A rotating arm that is disposed in the vicinity of the imaging unit of the rotating arm, and a distance measuring unit that measures the distance to the imaging region; and the rotation arm is moved based on the distance measured by the distance measuring unit, and the rotation The present invention is characterized in that a control unit is provided that causes the trajectory of the rotation center of the arm to follow a part row formed by the plurality of imaging parts. With this configuration, since the X-ray focal point position and the position of the imaging region match, an image of the subject with less blur can be captured.

  Further, the X-ray irradiated by the X-ray irradiation unit can be configured to have a focal point at the position of the rotation center of the rotary arm. Even if the rotary arm is rotated, the focal position does not move, and an image with less blur can be taken.

  Moreover, the said part row | line | column is a dentition, and the said control part can also be set as the structure which follows the track | orbit of the rotation center of the said rotation arm along a dentition.

  Moreover, the said control part can also be set as the structure which calculates | requires the distance to a dentition based on the distance to the body surface which the said ranging part measured. When the distance measuring unit uses ultrasonic waves or electromagnetic waves, depending on the wavelength, the ultrasonic waves or electromagnetic waves do not reach the dentition and the distance to the dentition cannot be measured. In this configuration, even when ultrasonic waves or electromagnetic waves do not reach the dentition, the distance to the dentition can be obtained by correcting the distance to the body surface.

  The imaging unit may be configured with a semiconductor element.

  In addition, the distance measuring unit may include an ultrasonic transmitter and an ultrasonic receiver.

  In addition, the distance measuring unit may include an electromagnetic wave transmitter and an electromagnetic wave receiver.

  The electromagnetic wave transmitter transmits a laser, and the electromagnetic wave receiver receives the laser. Since the laser has directivity, it can be transmitted only to the imaging region, the transmission power can be reduced, and the distance to the imaging region can be accurately measured.

  ADVANTAGE OF THE INVENTION According to this invention, the panoramic X-ray imaging apparatus which can image | photograph a picked-up image with small blur irrespective of the shape of a dentition can be provided.

  Hereinafter, a panoramic X-ray imaging apparatus according to an embodiment of the present invention will be described with reference to the drawings.

(First embodiment)
First, the configuration of the panoramic X-ray imaging apparatus according to the first embodiment will be described. FIG. 1 is a perspective view showing a configuration example of a panoramic X-ray imaging apparatus according to the present embodiment. A description will be given by taking a dentition as an imaging part.

  An X-ray irradiation unit 1 and an imaging unit 2 are disposed at each end of the rotary arm 3, and a distance measuring unit 8 is disposed in the vicinity of the imaging unit 2. The distance measuring unit 8 is connected to the control unit 4, and the rotation arm 3 is controlled to move by the control unit 4.

  The X-ray irradiation unit 1 irradiates the patient's jaw with X-rays having a focal point at a distance half that of the rotary arm 3. The imaging unit 2 includes an X-ray film or a semiconductor imaging element that receives X-rays transmitted through the patient's jaw as an image. The rotating arm 3 is capable of rotating in the direction indicated by the arrow 5 (hereinafter referred to as direction 5) and moving in the direction indicated by the arrows 6 and 7 (hereinafter referred to as directions 6 and 7). As the rotary arm 3 rotates, the X-ray irradiation unit 1 and the imaging unit 2 can scan the dentition. The distance measuring unit 8 includes a laser transmitter, a laser receiver, and the like, and is disposed in the vicinity of the imaging unit 2, and can measure the distance to the patient's dentition without contact. The reason why the distance measuring unit 8 is disposed in the vicinity of the imaging unit 2 is to accurately measure the distance between the X-ray irradiation unit 1 and the dentition. Based on the data from the distance measuring unit 8, the control unit 4 controls the movement of the rotary arm 3 in the direction 5 and the directions 6 and 7 so that the shape of the dentition coincides with the orbit of the rotation center of the rotary arm 3. It can be performed.

  FIG. 2 is a diagram showing a standard shape 9 (indicated by a solid line) and a rotation center trajectory 10 (indicated by a broken line) with respect to the dentition. The standard shape 9 is a line indicating a standard dentition shape set for the dentition, and the rotation center trajectory 10 is the X-ray irradiation unit 1 of the panoramic X-ray imaging apparatus according to the present embodiment. Orbit of the center of rotation. The trajectory 10 at the center of rotation reflects the actual dentition compared to the standard dentition shape 9. For this reason, the cross section of the tooth can be imaged at the focal position of the X-ray, and blur of the captured image can be reduced.

  Next, the operation of the panoramic X-ray imaging apparatus configured as described above will be described. First, the distance measuring unit 8 irradiates a portion of a tooth row to be imaged with laser. The distance measuring unit 8 measures the distance to the dentition with the laser reflected by the dentition. The control unit 4 controls the position of the rotary arm 3 so that the distance to the tooth row is half the length of the rotary arm 3, that is, the rotation center of the rotary arm 3 is positioned on the shape of the tooth row. . When the position of the rotary arm 3 is determined, X-rays are irradiated from the X-ray irradiation unit 1 onto the portion of the dentition to be imaged. The imaging unit 2 receives X-rays transmitted through the dentition, and an image processing device (not shown) performs signal processing on the received light signal and displays it as a dentition image. Next, the rotary arm 3 is moved by a minute section, and the distance measuring unit 8 measures the distance from the region near the photographed tooth row to the next tooth portion to be photographed. The above operation is repeated to photograph the patient's dentition.

  In the panoramic X-ray imaging apparatus of the present embodiment, an example in which the distance to the dentition is measured using a laser is shown, but electromagnetic waves or ultrasonic waves other than the laser may be used. Moreover, it is preferable that electromagnetic waves or ultrasonic waves have directivity.

  Moreover, it is preferable to use a laser having a wavelength with a relatively high transmittance on the surface of the jaw body. Even for electromagnetic waves other than lasers, those having a wavelength with a relatively high transmittance on the surface of the jaw part body can be used. Even an ultrasonic wave having a wavelength with a relatively high transmittance on the surface of the jaw part body can be used. Moreover, when using an ultrasonic wave, you may measure using the relationship between time, an echo signal, and an attenuation factor.

  Further, if the dentition is partially grasped, the length can be measured by directly applying a laser, an ultrasonic wave or the like to the dentition with the lips opened.

  As described above, since the panoramic X-ray imaging apparatus according to the present embodiment sequentially measures the distance between the X-ray irradiation unit 1 and the dentition, it is possible to shoot a photographic image with small blur regardless of the dentition. .

(Second Embodiment)
Since ultrasonic waves and electromagnetic waves have a low transmittance on the surface of the jaw body, the usable wavelength region is limited. Therefore, the panoramic X-ray imaging apparatus according to the second embodiment obtains the distance to the jaw body surface using ultrasonic waves having high reflectance on the jaw body surface, and corrects the distance. It is the structure which calculates | requires the distance to a dentition by performing.

  The panoramic X-ray imaging apparatus according to the second embodiment of the present invention is the same as that of the first embodiment except that the rotating arm 3b, the control unit 4b, and the distance measuring unit 8b are different, see FIG. While explaining. The rotating arm 3b, the control unit 4b, and the distance measuring unit 8b are arranged at the same positions as the rotating arm 3, the control unit 4, and the distance measuring unit 8 shown in FIG.

  The distance measuring unit 8b includes an ultrasonic transmitter and a receiver, irradiates the patient's jaw surface with ultrasonic waves, receives the reflected wave, and measures the distance to the jaw surface. Since the jaw unit body surface is determined by the shape of the dentition, the control unit 4b can detect the dentition by performing correction to add the sebum thickness to the distance to the jaw unit surface measured by the distance measuring unit 8b. it can. The control unit 8b performs rotation and movement control of the rotary arm 3b so that the orbit of the rotation center of the rotary arm 3b matches the shape of the dentition obtained by the correction. While the rotary arm 3b rotates, the X-ray irradiation device 1 irradiates the patient's dentition with X-rays, and the imaging unit 2 receives the X-rays that have passed through the patient's dentition, thereby imaging the dentition. can do.

  In the panoramic X-ray imaging apparatus of the present embodiment, an example in which the distance to the dentition is measured using an ultrasonic wave is shown, but an electromagnetic wave such as a laser may be used. It is preferable that the ultrasonic wave and the electromagnetic wave have directivity. In particular, the electromagnetic wave in the optical region is preferably a laser.

  Moreover, it is preferable to use an ultrasonic wave having a wavelength with a relatively high reflectance on the surface of the jaw body. An electromagnetic wave having a wavelength having a relatively high reflectance on the surface of the jaw body can be used.

  As described above, since the panoramic X-ray imaging apparatus according to the present embodiment sequentially measures the distance between the X-ray irradiation unit 1 and the dentition, it is possible to capture a photographic image with small blur regardless of the dentition. is there.

  Further, particularly in the case of ultrasonic waves, the reflectance on the jaw body surface is high, and the degree of freedom of the wavelength used for the distance measuring unit 8b can be increased.

  The distance measuring units 8 and 8b are not limited to electromagnetic waves and ultrasonic waves including lasers, but may be anything that can measure the distance to the dentition or the jaw surface.

  Further, the distance measuring units 8 and 8 b are not necessarily arranged in the vicinity of the imaging unit 2, and may be arranged in the vicinity of the X-ray irradiation unit 1.

  In addition, an example is shown in which the focus of the X-ray from the distance measuring unit is fixed to a half of the distance of the rotary arm, and the rotation center is set to the center position of the rotary arm, and the rotation control of the rotary arm is performed. Further, if the rotation center of the rotary arm is moved along a similar shape to the shape of the dentition, the focal point can be fixed to a length other than half the distance of the rotary arm. Further, the rotation center can be shifted from the center position of the rotation arm, and the X-ray focal point can be controlled in accordance with the rotation center position.

  The panoramic X-ray imaging apparatus according to the first and second embodiments is merely an example, and can be performed not only on the dentition but also on other parts.

  Since the present invention sequentially measures the distance between the X-ray irradiation unit and the dentition, the dentition image is taken by irradiating the focused dentition to the dentition, so that a photographed image with small blur can be taken. It can be used in the field of dentistry.

The perspective view of the panoramic X-ray imaging apparatus in this Embodiment Diagram showing actual dentition, standard dentition trajectory, and X-ray focal position trajectory A perspective view of a conventional panoramic X-ray imaging apparatus Arrangement diagram showing conventional X-ray irradiation unit, imaging unit and dentition

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 X-ray irradiation part 2 Imaging part 3 Rotating arm 4 Control part 8 Distance measuring part 9 Standard shape 10 Orbit of rotation center

Claims (8)

An X-ray irradiating unit that irradiates the subject with X-rays, and a rotating arm having an imaging unit at each end for detecting X-rays transmitted through the subject;
A distance measuring unit that is disposed near the imaging unit of the rotating arm and measures the distance to the imaging region;
A control unit is provided that moves the rotating arm based on the distance measured by the ranging unit, and causes the orbit of the rotation center of the rotating arm to follow a part row formed by the plurality of imaging parts. Panoramic X-ray imaging device.   The panoramic X-ray imaging apparatus according to claim 1, wherein the X-ray irradiated by the X-ray irradiation unit has a focal point at a position of a rotation center of the rotary arm.   The panoramic X-ray imaging apparatus according to claim 1, wherein the part row is a dentition, and the control unit causes the rotation center of the rotary arm to follow the dentition.   The panoramic X-ray imaging apparatus according to claim 3, wherein the control unit obtains a distance to a dentition based on a distance to a body surface measured by the distance measuring unit.   The panoramic X-ray imaging apparatus according to claim 1, wherein the imaging unit is configured by a semiconductor element.   The panoramic X-ray imaging apparatus according to any one of claims 1 to 5, wherein the distance measuring unit includes an ultrasonic transmitter and an ultrasonic receiver.   The panoramic X-ray imaging apparatus according to claim 1, wherein the distance measuring unit includes an electromagnetic wave transmitter and an electromagnetic wave receiver.   The panoramic X-ray imaging apparatus according to claim 7, wherein the electromagnetic wave transmitter transmits a laser, and the electromagnetic wave receiver receives the laser.

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