阅读说明：本技术 乳腺x光机及乳腺成像防人体遮挡方法 (Breast X-ray machine and breast imaging human body shielding prevention method ) 是由 陈旭 吴涛 杨子寒 于 2020-12-23 设计创作，主要内容包括：本发明公开了一种乳腺X光机,并公开了应用乳腺X光机的乳腺成像防人体遮挡方法,其中乳腺X光机,包括：机架,连接臂和检测装置；所述机架上设有成像受台和压迫板,所述压迫板位于所述成像受台上方且能够上下移动,所述压迫板和所述成像受台之间形成挤压区域；所述连接臂设于所述机架上,所述连接臂上设有X光发射器,所述X光发射器远离所述成像受台的外侧,所述X光发射器朝向所述成像受台；所述检测装置设于所述X光发射器的一侧且靠近所述成像受台的外侧,所述检测装置能够检测从所述成像受台的外侧接近所述X光发射器照射区域的物体并发出提示信息。本发明可以在不干涉受检者的其他身体部位活动的同时,有效防止受检人体的其他部位进入X光的照射区域,提高乳腺成像的质量。(The invention discloses a mammary gland X-ray machine and discloses a mammary gland imaging human body shielding prevention method applying the mammary gland X-ray machine, wherein the mammary gland X-ray machine comprises: the device comprises a frame, a connecting arm and a detection device; an imaging receiving platform and a compression plate are arranged on the machine frame, the compression plate is positioned above the imaging receiving platform and can move up and down, and a compression area is formed between the compression plate and the imaging receiving platform; the connecting arm is arranged on the rack, an X-ray emitter is arranged on the connecting arm, the X-ray emitter is far away from the outer side of the imaging receiving platform, and the X-ray emitter faces the imaging receiving platform; the detection device is arranged on one side of the X-ray emitter and close to the outer side of the imaging receiving platform, and can detect an object approaching the irradiation area of the X-ray emitter from the outer side of the imaging receiving platform and send out prompt information. The invention can effectively prevent other parts of the examined human body from entering the irradiation area of the X-ray while not interfering the movement of other parts of the examined human body, thereby improving the quality of mammary gland imaging.)

1. A breast X-ray machine, comprising:

the imaging device comprises a machine frame (100), wherein an imaging receiving platform (120) and a compression plate (110) are arranged on the machine frame (100), the compression plate (110) is positioned above the imaging receiving platform (120) and can move up and down, and a compression area is formed between the compression plate (110) and the imaging receiving platform (120);

the connecting arm (200), the connecting arm (200) is arranged on the rack (100), an X-ray emitter (230) is arranged on the connecting arm (200), the X-ray emitter (230) is far away from the outer side of the imaging subject table (120), and the X-ray emitter (230) faces the imaging subject table (120);

the detection device (240) is arranged on one side of the X-ray emitter (230) and close to the outer side of the imaging platform (120), and the detection device can detect an object approaching the irradiation area of the X-ray emitter (230) from the outer side of the imaging platform (120) and send prompt information.

2. The breast X-ray machine according to claim 1,

the detection device (240) is a light irradiator directed towards the outer edge of the imaging subject table (120).

3. The breast X-ray machine according to claim 2,

the light irradiator is a low-power laser, and a beam expanding lens is arranged in the low-power laser.

4. The breast X-ray machine according to claim 2,

the light irradiator is arranged vertically downwards.

5. The breast X-ray machine according to claim 1,

the connecting arm (200) is rotatably connected with the frame (100).

6. The breast X-ray machine according to claim 5,

connecting arm (200) include vertical arm section (220) and horizontal arm section (210), the tip of vertical arm section (220) with the end connection of horizontal arm section (210), be equipped with rotation axis (130) on frame (100), vertical arm section (220) be equipped with rotation axis (130) complex changes the hole, X light emitter (230) with detection device (240) are located on the horizontal arm section (210).

7. The breast X-ray machine according to claim 1,

the compression plate (110) is slidably connected with the frame (100).

8. The breast X-ray machine according to claim 7,

one of the rack (100) and the compression plate (110) is provided with a sliding groove, and the other is provided with a sliding block matched with the sliding groove.

9. A method for preventing human body from being blocked in breast imaging is characterized by comprising the following steps:

placing a breast (310) of a subject in the compression region of the breast X-ray machine of any of claims 1 to 8 with a chest wall side of the subject abutting a side wall of the compression paddle and a side wall of the imaging table, respectively;

adjusting the compression plate (110) to move downwards to enable the breast (310) of the examinee to be clamped and fixed in the compression area;

and (3) starting the detection device (240), and simultaneously starting an X-ray emitter (230) to perform irradiation scanning on the mammary gland.

Technical Field

The invention relates to the field of mammary gland X-ray photography, in particular to a mammary gland X-ray machine and a human body shielding prevention method.

Background

When carrying out mammary gland X-ray photography and examining, at first will fix the mammary gland and receive between platform and the X-ray emitter imaging, imaging receives the bench and is equipped with the mammary gland layer board, can with the breast direct contact of examinee, when fixed mammary gland, will place the examinee's breast on the formation of image region of mammary gland layer board, and simultaneously, chest wall side butt is on the lateral wall of mammary gland layer board and formation of image platform, make the mammary gland stretch into to the greatest extent in the formation of image region, then compress downwards through the oppression board of mammary gland layer board top, receive the platform cooperation with the formation of image and fix the breast centre gripping, thereby fix the mammary gland and flat gland, make things convenient for the photography. If the head, shoulders and other body parts of the examined person approach and block the X-ray, an effective mammary gland image cannot be obtained, and correct diagnosis cannot be made on the image, so that the waste film is caused.

In order to prevent other body parts such as the head and shoulders of the subject from blocking the X-rays, a blocking plate is generally provided on the X-ray machine to block the other body parts such as the head and shoulders of the subject from entering the X-ray irradiation region. However, this method interferes with the movement of other body parts of the subject, reduces the comfort of the subject, and particularly brings the face of the subject into close contact with the shielding plate, which adversely affects the hygiene of the face of the subject.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention provides a mammary gland X-ray machine which can effectively prevent other parts of the examined human body from entering an X-ray irradiation area while not interfering the movement of other parts of the examined human body, thereby improving the quality of mammary gland imaging.

The invention also provides a mammary gland imaging human body shielding prevention method applying the mammary gland X-ray machine.

A breast X-ray machine according to an embodiment of a first aspect of the invention comprises: the device comprises a frame, a connecting arm and a detection device; an imaging receiving platform and a compression plate are arranged on the machine frame, the compression plate is positioned above the imaging receiving platform and can move up and down, and a compression area is formed between the compression plate and the imaging receiving platform; the connecting arm is arranged on the rack, an X-ray emitter is arranged on the connecting arm, the X-ray emitter is far away from the outer side of the imaging receiving platform, and the X-ray emitter faces the imaging receiving platform; the detection device is arranged on one side of the X-ray emitter and close to the outer side of the imaging receiving platform, and can detect an object approaching the irradiation area of the X-ray emitter from the outer side of the imaging receiving platform and send out prompt information.

In the above embodiment, as shown in the drawing, when the mammography imaging operation is performed, the breast of the subject is placed in the compressed region, and the chest wall side of the subject abuts against the side wall of the compression plate and the side wall of the imaging table, respectively, so that the breast extends into the compressed region as much as possible, thereby improving the imaging quality; the compression plate is adjusted to move downwards, so that the breasts of the examinee are clamped and fixed in the extrusion area, on one hand, the breasts can be fixed on the imaging receiving table to prevent the breasts from moving, and on the other hand, the breasts can be flattened, and the X-ray can penetrate through the breasts; and then the detection device and the X-ray emitter are started, the X-ray emitter performs mammography imaging, if other body parts such as the head, the shoulders and the like of the human body approach the irradiation area of the X-ray emitter from the outer side of the imaging receiving table, the other body parts are detected by the detection device, prompt information is sent out to prompt the examinee to approach the X-ray beam, and the examinee is warned to move away as soon as possible. Therefore, the other parts of the examined human body can be effectively prevented from entering the irradiation area of the X-ray while the movement of other parts of the examined human body is not interfered, and the breast imaging quality is improved.

When the X-ray irradiates the mammary gland, the X-ray has penetrability, the density and the thickness of different tissues of a human body are different, after the X-ray penetrates through the mammary gland of the human body, the degree of the X-ray absorbed by each tissue part of the mammary gland is different, and the imaging receiving platform is used for receiving the X-ray penetrating through the mammary gland tissue, so that the image of the mammary gland tissue is formed on the imaging receiving platform film.

According to some embodiments of the present invention, the detecting device is a light irradiator, the light irradiator faces the outer edge of the imaging table, during the breast detection, the illumination emitter emits visible light toward the outer edge of the imaging table, and if other body parts of the subject enter the illumination area of the illumination emitter, an obvious light emitting profile is irradiated, which is equivalent to a prompt message to the subject, so as to achieve the effect of detecting and prompting the subject to approach the illumination area of the X-ray emitter.

According to some embodiments of the invention, the light irradiator is arranged vertically downwards, so that the illumination area of the light irradiator is positioned between the examinee and the X-ray illumination area, and the detection accuracy of the detection device is improved.

Further, according to some embodiments of the present invention, the light irradiator is a low power laser, and a beam expanding lens is disposed in the low power laser, wherein the low power laser can be a laser with a wavelength of 650nm and a power of 1mW, and can directly irradiate a human body without harmfulness to the human body, as shown in the figure, the emitted laser changes the emission angle of the laser beam through the beam expanding lens to form a fan-shaped laser curtain, the fan-shaped laser curtain is located between an examinee and an irradiation area of the X-ray emitter, and an object entering the fan-shaped laser curtain means that the object is close to the irradiation area of the X-ray emitter and is irradiated with a significantly bright profile, and the divergence characteristic of the fan-shaped laser curtain enables a detection device to have a larger detection range.

Wherein, low-power laser instrument can specifically set up to semiconductor laser has small, light in weight, the reliability is high, long service life, advantage that the consumption is low, because its light beam still has the great characteristics of angle of divergence, cooperation cylinder beam expanding lens can make the laser that gives out have a great fan-shaped covering surface, can be marked out by fan-shaped laser curtain at once after guaranteeing that other positions of human body are close to the irradiation region of X-ray, plays effectual warning effect to the person of being examined.

Of course, in other embodiments, the low power laser may be a solid state laser, a gas laser, etc., and may function as a safety detection indicator under low power conditions.

Of course, in other embodiments, the light irradiator may be configured as a lamp emitting normal visible light, and may also serve to detect the proximity of the irradiation region of the X-ray emitter and to emit a prompt message.

It is conceivable that, in other embodiments, the detection device may also include a photoelectric sensor and a buzzer, the photoelectric sensor faces the edge of the top surface of the imaging platform, the photoelectric sensor is electrically connected to the buzzer, the photoelectric sensor is specifically configured as a grating sensor, and has a wider detection range, the detection light curtain of the photoelectric sensor is located between the subject and the irradiation area of the X-ray emitter, and if another body part of the subject enters the detection light curtain of the photoelectric sensor, a prompt warning of the buzzer is triggered, so as to play a role of sending a prompt message, prompt the subject to move away as soon as possible, and prevent another body part of the subject from blocking the irradiation of the X-ray emitter.

According to some embodiments of the invention, the connecting arm is rotatably connected with the frame, and the X-ray emitter is arranged on the connecting arm and can rotate along with the rotation of the connecting arm, so that the irradiation angle of the X-ray emitter can be adjusted, the exposure and shooting of the breast of the examined person can be performed in multiple angles, the X-ray imaging quality of the breast is improved, and the accuracy of breast imaging diagnosis is improved. The sheltering prevention principle of combining above-mentioned embodiment has avoided the clean problem that traditional shielding plate directly exists with human face contact, has also avoided traditional shielding plate to rotate along with the linking arm because of setting up on the linking arm, and lead to the condition emergence of the examined person face of injure.

According to some embodiments of the invention, the connecting arm comprises a vertical arm section and a horizontal arm section, the end of the vertical arm section is connected with the end of the horizontal arm section, the rack is provided with a rotating shaft, the vertical arm section is provided with a rotating hole matched with the rotating shaft, and the X-ray emitter and the detection device are arranged on the horizontal arm section, so that the X-ray emitter can rotate around the rotating shaft, thereby realizing the function of shooting and imaging the mammary gland in multiple angles.

According to some embodiments of the present invention, the compression paddle and the frame are slidably connected such that the compression paddle can move up and down to adjust the distance between the compression paddle and the imaging table for effective compression fixation of the subject's breast.

In other embodiments, an electric push rod, an air cylinder or a hydraulic telescopic part is arranged on the frame, and the compression plate is connected with the movable part of the telescopic part, so that the telescopic part can drive the compression plate to move up and down.

According to some embodiments of the invention, the rack is provided with a sliding groove, the compression plate is provided with a sliding block matched with the sliding groove, and the sliding connection between the compression plate and the rack is realized through the matching of the sliding block and the sliding groove, so that the compression plate can move up and down. Of course, in other embodiments, the positions of the sliding groove and the sliding block can be interchanged, and the sliding connection of the compression plate and the machine frame can also be realized.

According to a second aspect of the invention, the breast imaging human body blocking prevention method is characterized by comprising the following steps: placing a breast of a subject in the compression region of the breast X-ray machine of any one of the claims to, with a chest wall side of the subject abutting a side wall of the compression paddle and a side wall of the imaging table, respectively; adjusting the compression plate to move downwards so that the breast of the examinee is clamped and fixed in the compression area; and starting the detection device, and simultaneously starting the X-ray emitter to carry out irradiation scanning on the mammary gland.

The method for preventing the human body from being blocked in the breast imaging provided by the embodiment of the invention at least has the following beneficial effects: in the breast detection process, if other body parts such as the head, the shoulders and the like of the examinee approach the irradiation area of the X-ray emitter from the outer side of the imaging receiving table, the examinee is detected by the detection device, and prompt information is sent to prompt the examinee that the examinee approaches the X-ray beam and warn the examinee to move away as soon as possible. Therefore, the other parts of the examined human body can be effectively prevented from entering the irradiation area of the X-ray while the movement of other parts of the examined human body is not interfered, and the breast imaging quality is improved.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a schematic view of a breast X-ray machine according to an embodiment of the present invention;

fig. 2 is another view angle schematic diagram of the breast X-ray machine shown in fig. 1.

Reference numerals:

a frame 100, a compression paddle 110, an imaging subject table 120, a rotating shaft 130, a connecting arm 200, a horizontal arm segment 210, a vertical arm segment 220, an X-ray emitter 230, an X-ray irradiation area 231, a detection device 240, a fan-shaped laser curtain 241, a breast 310, a chest wall side 320.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

In the description of the present invention, it should be understood that the orientation or positional relationship referred to in the description of the orientation, such as the upper, lower, front, rear, left, right, etc., is based on the orientation or positional relationship shown in the drawings, and is only for convenience of description and simplification of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, the meaning of a plurality of means is one or more, the meaning of a plurality of means is two or more, and larger, smaller, larger, etc. are understood as excluding the number, and larger, smaller, inner, etc. are understood as including the number. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present invention, unless otherwise explicitly limited, terms such as arrangement, installation, connection and the like should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above terms in the present invention in combination with the specific contents of the technical solutions.

As shown in fig. 1 and 2, a breast X-ray machine according to an embodiment of the first aspect of the present invention includes: the frame 100, the connecting arm 200 and the detection device 240; an imaging receiving platform 120 and a compression plate 110 are arranged on the machine frame 100, the compression plate 110 is positioned above the imaging receiving platform 120 and can move up and down, and a compression area is formed between the compression plate 110 and the imaging receiving platform 120; the connecting arm 200 is arranged on the stand 100, the connecting arm 200 is provided with an X-ray emitter 230, the X-ray emitter 230 is far away from the outer side of the imaging receiving platform 120, and the X-ray emitter 230 faces the imaging receiving platform 120; the detection device 240 is disposed on one side of the X-ray emitter 230 and close to the outer side of the imaging platform 120, and is capable of detecting an object approaching the irradiation area of the X-ray emitter 230 from the outer side of the imaging platform 120 and sending a prompt message.

In the above embodiment, as shown in fig. 1, when the mammography operation is performed, the breast 310 of the subject is placed in the compressed region, and the chest wall side 320 of the subject abuts against the side wall of the compression plate and the side wall of the imaging table, respectively, so that the breast extends into the compressed region as much as possible, thereby improving the imaging quality; the compression plate 110 is adjusted to move downwards, so that the breasts 310 of the examinee are clamped and fixed in the compression area, on one hand, the breasts can be fixed on the imaging receiving table 120 to prevent the breasts from moving, and on the other hand, the breasts can be flattened to facilitate the X-rays to penetrate the breasts; then, the detection device 240 and the X-ray emitter 230 are turned on, the X-ray emitter images the mammography, and if other body parts such as the head, the shoulders and the like of the human body approach the irradiation area of the X-ray emitter 230 from the outside of the imaging table 120, the other body parts are detected by the detection device and send out prompt information to prompt the examinee to approach the X-ray beam, so as to warn the examinee to move away as soon as possible. Therefore, the other parts of the examined human body can be effectively prevented from entering the irradiation area of the X-ray while the movement of other parts of the examined human body is not interfered, and the breast imaging quality is improved.

When the X-ray irradiates the mammary gland, the X-ray has penetrability, the density and the thickness of different tissues of a human body are different, after the X-ray penetrates through the mammary gland of the human body, the degree of the X-ray absorbed by each tissue part of the mammary gland is different, and the imaging receiving platform 120 is used for receiving the X-ray penetrating through the mammary gland tissue, so that the image of the mammary gland tissue is formed on the film of the imaging receiving platform 120.

According to some embodiments of the present invention, the detecting device 240 is a light irradiator, the light irradiator faces the outer edge of the imaging platform 120, during the breast detection, the illumination emitter emits visible light toward the outer edge of the imaging platform 120, and if other body parts of the subject enter the illumination area of the illumination emitter, an obvious light emitting profile is irradiated, which is equivalent to a prompt message to the subject, so as to achieve the effect of detecting and prompting the subject to approach the illumination area of the X-ray emitter.

According to some embodiments of the invention, the light irradiator is arranged vertically downward, so that the illumination area of the light irradiator is positioned between the subject and the X-ray illumination area, thereby improving the detection accuracy of the detection device.

Further, according to some embodiments of the present invention, the light irradiator is a low power laser, and a beam expanding lens is disposed in the low power laser, wherein the low power laser can adopt a laser with a wavelength of 650nm and a power of 1mW, and can directly irradiate a human body without harm to the human body, as shown in fig. 2, the emitted laser changes the emission angle of the laser beam through the beam expanding lens to form a fan-shaped laser curtain 241, the fan-shaped laser curtain is located between the subject and the irradiation area of the X-ray emitter, and the object entering the fan-shaped laser curtain 241 means approaching the irradiation area of the X-ray emitter, and is irradiated with a significantly bright profile, and the divergence characteristic of the fan-shaped laser curtain enables the detection device to have a larger detection range.

Wherein, low-power laser instrument can specifically set up to semiconductor laser has small, light in weight, the reliability is high, long service life, advantage that the consumption is low, because its light beam still has the great characteristics of angle of divergence, cooperation cylinder beam expanding lens can make the laser that gives out have a great fan-shaped covering surface, can be marked by fan-shaped laser curtain 241 at once after guaranteeing that other positions of human body are close to the irradiation region of X-ray, plays effectual warning effect to the person of being examined.

Of course, in other embodiments, the low power laser may be a solid state laser, a gas laser, etc., and may function as a safety detection indicator under low power conditions.

Of course, in other embodiments, the light irradiator may be configured as a lamp emitting normal visible light, and may also serve to detect the proximity of the irradiation region of the X-ray emitter and to emit a prompt message.

It is conceivable that, in other embodiments, the detection device may also include a photoelectric sensor and a buzzer, the photoelectric sensor faces the edge of the top surface of the imaging platform, the photoelectric sensor is electrically connected to the buzzer, the photoelectric sensor is specifically configured as a grating sensor, and has a wider detection range, the detection light curtain of the photoelectric sensor is located between the subject and the irradiation area of the X-ray emitter, and if another body part of the subject enters the detection light curtain of the photoelectric sensor, a prompt warning of the buzzer is triggered, so as to play a role of sending a prompt message, prompt the subject to move away as soon as possible, and prevent another body part of the subject from blocking the irradiation of the X-ray emitter.

According to some embodiments of the present invention, the connecting arm 200 is rotatably connected to the frame 100, and the X-ray emitter 230 is disposed on the connecting arm 200 and can rotate along with the rotation of the connecting arm 200, so that the irradiation angle of the X-ray emitter 230 can be adjusted, the exposure and the shooting of the breast of the subject can be performed in multiple angles, the X-ray imaging quality of the breast can be improved, and the accuracy of the breast imaging diagnosis can be improved. The sheltering prevention principle of combining above-mentioned embodiment has avoided the clean problem that traditional shielding plate directly exists with human face contact, has also avoided traditional shielding plate to rotate along with linking arm 200 because of setting up on linking arm 200, and lead to the condition emergence of the examinee face of wounding.

According to some embodiments of the present invention, the connecting arm 200 includes a vertical arm section 220 and a horizontal arm section 210, an end of the vertical arm section 220 is connected to an end of the horizontal arm section 210, the rack 100 is provided with a rotating shaft 130, the vertical arm section 220 is provided with a rotating hole matched with the rotating shaft 130, and the X-ray emitter 230 and the detecting device 240 are provided on the horizontal arm section 210, so that the X-ray emitter 230 can rotate around the rotating shaft 130, thereby implementing a multi-angle shooting and imaging function on the breast.

According to some embodiments of the present invention, the compression paddle 110 and the gantry 100 are slidably coupled such that the compression paddle 110 can move up and down to adjust the spacing between the compression paddle 110 and the imaging table for effective compression fixation of the subject's breast 310.

It is contemplated that in other embodiments, the frame 100 is provided with an electric push rod, an air cylinder, or a hydraulic expansion member, and the compression plate 110 is connected to the movable portion of the expansion member, so that the expansion member can drive the compression plate 110 to move up and down.

According to some embodiments of the present invention, the rack 100 is provided with a sliding groove, the compression plate 110 is provided with a sliding block matched with the sliding groove, through the matching of the sliding block and the sliding groove, the sliding connection between the compression plate 110 and the rack 100 is realized, and the compression plate 110 can move up and down. Of course, in other embodiments, the positions of the sliding grooves and the sliding blocks can be interchanged, and the sliding connection between the compression plate 110 and the frame 100 can also be realized.

According to a second aspect of the invention, the breast imaging human body blocking prevention method is characterized by comprising the following steps: placing the breast of the subject in the compression area of the breast X-ray machine according to any one of claims 1 to 9 with the chest wall side of the subject abutting the side wall of the compression paddle and the side wall of the imaging table, respectively; adjusting the compression plate 110 to move downwards to clamp and fix the breast of the examinee in the compression area; the detection device 240 is turned on, and at the same time, the X-ray emitter 230 is turned on to scan the breast.

The method for preventing the human body from being blocked in the breast imaging provided by the embodiment of the invention at least has the following beneficial effects: in the breast detection process, if other body parts such as the head and the shoulders of the examinee approach the irradiation area of the X-ray emitter 230 from the outside of the imaging table 120, the examinee will be detected by the detection device and send prompt information to prompt the examinee to approach the X-ray beam and warn the examinee to move away as soon as possible. Therefore, the other parts of the examined human body can be effectively prevented from entering the irradiation area of the X-ray while the movement of other parts of the examined human body is not interfered, and the breast imaging quality is improved.

The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The present embodiment has been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above-described embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the present invention.