Intraoral receiving sensor and intraoral positioning system

Abstract

The utility model belongs to the technical field of oral cavity imaging equipment, and relates to an intraoral receiving sensor, the intraoral receiving sensor comprises a shell, a photosensitive assembly and a magnet, the photosensitive assembly is arranged in the shell and is used for receiving X-rays emitted by a ray emitting device; the magnet is used for being used in cooperation with a ray emitting device so as to position the in-mouth receiving sensor. The utility model further relates to an intraoral positioning system, the magnet used for positioning is arranged in the intraoral receiving sensor, so that when the receiving ray emitting device is close to the intraoral receiving sensor, the position of the intraoral receiving sensor can be effectively detected, accurate positioning of the position of the intraoral receiving sensor is effectively achieved, and the positioning accuracy of the intraoral receiving sensor is improved. The detection result can be quickly obtained, compared with traditional image detection, the time and manpower for developing films can be saved, pictures can be shot at a time, repeated shooting is avoided, the treatment time is shortened, and the increase of the radiation dose of a patient caused by multiple times of shooting is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of oral imaging equipment, and more specifically, to an intraoral receiving sensor and an intraoral positioning system including the intraoral receiving sensor. Background Art

[0002] Dental imaging components include an extraoral radiator and an intraoral receiving sensor. The radiator emits X-rays, while the intraoral receiving sensor receives them, converts them into electrical signals, and ultimately outputs dental images to the client software. Compared to traditional imaging, digital imaging eliminates the time and labor required to develop film, eliminates the impact of chemical film-developing agents on the human body and the environment, and provides faster test results. However, many doctors struggle to master the correct angle and position of the intraoral receiving sensor during digital imaging. Consequently, deformed teeth are often captured, or even the desired teeth are not captured. This often requires multiple X-rays of the patient's teeth, which not only prolongs treatment time but also heightens patients' concerns about radiation dose. Utility Model Content

[0003] The technical problem to be solved by the embodiments of the present application is how to effectively and accurately locate the position of the receiving sensor.

[0004] In order to solve the above technical problems, the embodiment of the present application provides an intraoral receiving sensor, which adopts the following technical solution:

[0005] An intraoral receiving sensor comprises a shell, a photosensitive component and a magnet. The photosensitive component is arranged in the shell and is used to receive X-rays emitted by a ray emitting device to form a detection image; the magnet is used in conjunction with the ray emitting device to position the intraoral receiving sensor.

[0006] Furthermore, the magnet is arranged outside the shell.

[0007] Furthermore, the shell is outer-circuited with a protective sleeve, the protective sleeve is provided with a protective cavity, the magnet is arranged in the protective cavity, and the shell part is stuck in the protective cavity.

[0008] Furthermore, a positioning groove is provided on the protective cover.

[0009] Furthermore, a wire is connected to the photosensitive component, and a through hole is provided on the protective cover for the wire to pass through.

[0010] Furthermore, the magnet is arranged in the shell.

[0011] Furthermore, the shell is provided with a housing cavity for accommodating the photosensitive component and the magnet, and the magnet is fixed on the bottom wall of the housing cavity.

[0012] Furthermore, the photosensitive component includes a stacked PCB board, a conversion layer, and a receiving layer, the receiving layer is used to receive the X-rays emitted by the ray emitting device and convert them into visible light, the conversion layer is used to convert the visible light into an electrical signal, the PCB board is used to receive the electrical signal and convert it into a detection image output, and the receiving layer is arranged on the end of the conversion layer away from the magnet.

[0013] Furthermore, a fixing layer is provided between the PCB board and the conversion layer, and the conversion layer is fixed to the PCB board through the fixing layer. The photosensitive component also includes a reflective layer and a waterproof layer, and the waterproof layer is provided between the receiving layer and the reflective layer.

[0014] The present invention provides an intraoral positioning system, which adopts the following technical solutions:

[0015] An intraoral positioning system includes a ray emitting device and an intraoral receiving sensor. The ray emitting device is provided with an annular circuit board, and a position detection unit is provided on the annular circuit board. The position detection unit includes at least three groups of sensor components for detecting the position of the intraoral receiving sensor. The sensor components are arranged at intervals on the annular circumference of the annular circuit board.

[0016] Compared with the prior art, the embodiments of the present application have the following beneficial effects:

[0017] The present application provides a magnet for positioning in the intraoral receiving sensor, so that when the receiving ray emitting device is close to the intraoral receiving sensor, the position of the intraoral receiving sensor can be effectively detected, thereby effectively realizing accurate positioning of the position of the intraoral receiving sensor, so as to facilitate adjustment of the relative position between the ray emitting device and the intraoral receiving sensor. Not only can the detection results be obtained quickly, compared with traditional image detection, the time and manpower for developing films can be saved, and the image can be taken at one time to avoid repeated shooting, shorten the treatment time, and reduce the increase in radiation dose to the patient caused by multiple shooting. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the solutions in this application, a brief introduction will be given below to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of this application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0019] Figure 1 This is an exploded view of the intraoral receiving sensor of Example 1 of the present application;

[0020] Figure 2 This is a cross-sectional view of the intraoral receiving sensor according to the first embodiment of the present application;

[0021] Figure 3 This is a structural diagram of the intraoral receiving sensor according to the second embodiment of the present application;

[0022] Figure 4 This is an exploded view of the intraoral receiving sensor of Example 2 of the present application;

[0023] Figure 5 is a structural schematic diagram of a ray emitting device;

[0024] Figure 6 Schematic diagram of the structure of a ring circuit board;

[0025] Figure numerals: 1. Shell; 2. Magnet; 100. Intraoral receiving sensor; 200. Photosensitive component; 11. Accommodating cavity; 300. Ray emitting device; 3. Protective cover; 31. Protective cavity; 32. Positioning groove; 33. Through hole; 4. Ring circuit board; 5. Sensing component; 51. Mounting plate; 52. Detection sensor; 6. PCB board; 7. Conversion layer; 8. Receiving layer; 91. Fixing layer; 92. Reflective layer; 93. Waterproof layer; 400. Wire. DETAILED DESCRIPTION

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of the application are only for the purpose of describing specific embodiments and are not intended to limit this application. The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, not to describe a specific order.

[0027] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0028] Example 1

[0029] Reference Attachment Figure 1 To the attached Figure 2 An intraoral receiving sensor for use with a radiation emitting device 300. The intraoral receiving sensor 100 comprises a housing 1, a photosensitive component 200, and a magnet 2. The photosensitive component 200 is disposed within the housing 1 and is configured to receive X-rays emitted by the radiation emitting device 300 to form a detection image. The magnet 2 is configured to cooperate with the radiation emitting device 300 to position the intraoral receiving sensor 100. The magnet 2 is disposed within the intraoral receiving sensor 100 for positioning. When the radiation emitting device 300 approaches the intraoral receiving sensor 100, the position of the intraoral receiving sensor 100 can be effectively detected, thereby effectively achieving accurate positioning of the intraoral receiving sensor 100 and facilitating adjustment of the relative position between the radiation emitting device 300 and the intraoral receiving sensor 100. This not only allows for rapid detection results, but also saves the time and labor required to develop film compared to traditional imaging tests. Furthermore, the image can be captured and produced in a single shot, avoiding repeated exposures, shortening treatment time, and reducing the increase in radiation dose to the patient caused by multiple exposures.

[0030] Furthermore, the magnet 2 is disposed outside the housing 1. This facilitates disassembly and assembly of the magnet 2 when replacement or adjustment of the magnetic force is required. The external magnet can also be adjusted according to different application requirements, providing greater flexibility. There is no need to consider the installation location and installation space, thus reducing processing costs. Furthermore, it is convenient to retrofit an existing intraoral receiving sensor, thereby achieving accurate positioning of the intraoral receiving sensor 100 and facilitating adjustment of the relative position between the ray emitting device 300 and the intraoral receiving sensor 100. This allows for a single shot to generate an image, avoiding repeated shots, shortening treatment time, and reducing the increase in radiation dose to the patient caused by multiple shots.

[0031] Furthermore, the housing 1 is provided with a protective cover 3, the protective cover 3 being provided with a protective cavity 31, the magnet 2 being provided in the protective cavity 31, and the housing 1 being partially inserted into the protective cavity 31. The protective cover 3 not only protects the magnet 2, preventing the magnet 2 from directly contacting the inside of the patient's mouth, thereby preventing contamination and preventing the magnet 2 from failing, but also the magnet 2 is fixed in the protective cover 3, making it convenient to fix the magnet 2 and to fix the magnet 2 to the housing 1, thus avoiding errors in the shooting angle and position due to displacement of the magnet 2, reducing repeated shooting, shortening the treatment time, and reducing the increase in radiation dose to the patient caused by multiple shootings.

[0032] Furthermore, the magnet 2 is fixed to the protective cover 3 by 3M double-sided tape. At the same time, due to the limited space in some dental clinics and the wide variety of dental equipment, the intraoral receiving sensor 100 itself is small in size. After the detection is completed, if it is placed casually, it will take a lot of time to find it when it is used again. The magnet 2 of the present application is external to the shell 1 of the intraoral receiving sensor 100. The magnet 2 has an adsorption and placement function, so the intraoral receiving sensor 100 can be adsorbed and placed on the dental equipment or a specific position, which is convenient for taking it out when it is used again, reducing the searching time, and avoiding the contamination of the intraoral receiving sensor 100 caused by random placement, thereby improving the safety of the intraoral receiving sensor 100.

[0033] Furthermore, the protective sleeve 3 is provided with a positioning groove 32. The positioning groove 32 is coaxially arranged with the magnet 2, so that the position of the magnet 2 can be intuitively felt through visual observation and touch, further achieving accurate positioning of the intraoral receiving sensor 100, and facilitating adjustment of the relative position between the radiation emitting device 300 and the intraoral receiving sensor 100. This not only allows for rapid detection results, but also saves the time and labor of developing film compared to traditional imaging tests. Furthermore, images can be captured in a single shot, avoiding repeated shots, shortening treatment time, and reducing the increase in radiation dose to the patient caused by multiple shots. At the same time, the positioning groove 32 is formed inwardly to press and position the magnet 2.

[0034] Furthermore, the protective cover 3 is also provided with a groove for hand holding, which is convenient for users to take and use.

[0035] Furthermore, a wire 400 is connected to the photosensitive component 200, and a through hole 33 is provided on the protective cover 3 for the wire 400 to pass through, so as to facilitate threading.

[0036] Example 2

[0037] Reference Attachment Figure 3 To the attached Figure 4 The magnet 2 is disposed in the housing 1. This not only effectively protects the magnet 2, preventing it from directly contacting the inside of the patient's mouth, thus preventing contamination and preventing the magnet 2 from failing, but also the magnet 2 is fixed in the housing 1, making it convenient to fix the magnet 2, thus avoiding incorrect shooting angles and positions due to displacement of the magnet 2, reducing repeated shooting, shortening treatment time, and reducing the increase in radiation dose to the patient caused by multiple shootings.

[0038] Furthermore, the housing 1 is provided with a housing cavity 11 for accommodating the photosensitive component 200 and the magnet 2, and the magnet 2 is fixed to the bottom wall of the housing cavity 11. The magnet 2 is fixed to the bottom wall of the housing cavity 11 by 3M double-sided tape. At the same time, due to the limited space in some dental clinics and the wide variety of dental equipment, the intraoral receiving sensor 100 itself is relatively small in size. After the detection is completed, if it is placed casually, it will take a long time to search for it when it is used again. However, the magnet 2 built into the housing 1 of the intraoral receiving sensor 100 of the present application has an adsorption placement function, so the intraoral receiving sensor 100 can be adsorbed and placed on the dental equipment or a specific position, which is convenient for taking it out when it is used again, reducing the searching time, and avoiding the contamination of the intraoral receiving sensor 100 caused by random placement, thereby improving the safety of the intraoral receiving sensor 100.

[0039] Furthermore, the photosensitive component 200 includes a stacked PCB board 6, a conversion layer 7, and a receiving layer 8. The receiving layer 8 is used to receive the X-rays emitted by the ray emitting device 300 and convert them into visible light. The conversion layer 7 is used to convert the visible light into an electrical signal. The PCB board 6 is used to receive the electrical signal and convert it into a detection image output. The receiving layer 8 is arranged on the end of the conversion layer 7 away from the magnet 2, which is conducive to the X-rays directly hitting the receiving layer 8 and preventing the magnet 2 from blocking the X-rays.

[0040] Furthermore, a fixing layer 91 is provided between the PCB board 6 and the conversion layer 7, and the conversion layer 7 is fixed to the PCB board 6 via the fixing layer 91. The photosensitive component 200 also includes a reflective layer 92 and a waterproof layer 93, and the waterproof layer 93 is provided between the receiving layer 8 and the reflective layer 92. The fixing layer 91 can fix the conversion layer 7 to the PCB board 6, and has a simple structure and is easy to install. The waterproof layer 93 forms a sealed environment on the photosensitive component 200 to prevent damage to the photosensitive component 200. The photosensitive component 200 is used to receive X-rays and then perform corresponding conversion processing on the X-rays. Under the reflection effect of the reflective layer 92, the CMOS surface can convert more electrical signals, thereby improving the sensitivity of the intraoral receiving sensor 100, effectively ensuring that the product sensitivity requirements are met during application, and thus reducing the patient's X-ray radiation.

[0041] Furthermore, the conversion layer 7 is a wafer, the receiving layer 8 is made of cesium iodide, the fixing layer 91 is made of double-sided tape, the reflective layer 92 is made of white glue, and the waterproof layer 93 is made of parylene. A wafer is a semiconductor silicon wafer, a photoelectric conversion material that facilitates converting visible light into electrical signals. Cesium iodide is a photoconversion material, and during processing, cesium iodide is typically doped with thallium iodide to facilitate the conversion of X-rays by the receiving layer 8 into visible light. During processing, cesium iodide is deposited on the wafer via a vapor deposition process. The fixing layer 91 uses double-sided tape for easy fixation and reduced costs. The white glue, which includes silica gel and titanium dioxide, reflects visible light, allowing it to re-enter the receiving layer 8, thereby reducing X-ray radiation. Because the reflective layer 92 is made of white glue, it is processed using an automated dispensing process. The white glue is applied to the surface of the waterproof layer 93 through an automated dispensing process. After application, the glue is cured by high-temperature baking, forming a dense reflective layer 92 that reflects visible light. Parylene, a sealing material, provides waterproofing and protects the photosensitive component 200, improving product performance. During processing, the parylene is deposited on the cesium iodide using a vapor deposition method.

[0042] Reference Attachment Figure 5 To the attached Figure 6 An embodiment of the present application provides an intraoral positioning system comprising a radiation emitting device 300 and an intraoral receiving sensor 100. The radiation emitting device 300 is provided with an annular circuit board 4, which is provided with a position detection unit. The position detection unit comprises at least three sensor components 5 for detecting the position of the intraoral receiving sensor 100. The sensor components 5 are spaced apart on the circumference of the annular circuit board 4. The radiation emitting device 300 can effectively detect the position of the intraoral receiving sensor 100 through the sensor components 5 spaced apart on the annular circuit board 4, thereby effectively achieving accurate positioning of the receiving sensor and facilitating adjustment of the relative position between the radiation emitting device 300 and the intraoral receiving sensor 100. This system not only allows for rapid detection results, but also saves the time and labor required to develop film compared to traditional imaging tests. Furthermore, the system can capture images in a single pass, avoiding repeated imaging, shortening treatment time, and reducing the increased radiation dose to the patient caused by multiple imaging sessions.

[0043] Reference Attachment Figure 5 To the attached Figure 6Furthermore, each of the sensing components 5 includes a mounting plate 51 and six detection sensors 52. The detection sensors 52 are configured as Hall sensors. The position detection unit senses the position of the magnet 2 through the Hall effect of the Hall sensor, thereby achieving the positioning of the intraoral receiving sensor 100 and quickly obtaining the detection results. Compared with traditional image detection, it can save the time and manpower of developing films, and can also capture images in one shot, avoiding repeated shooting, shortening treatment time, and reducing the increase in radiation dose to the patient caused by multiple shooting.

[0044] Furthermore, the magnet 2 is arranged at the center position of the intraoral receiving sensor 100 to improve the accuracy of positioning. The position detection unit detects the position of the magnet 2 from multiple directions through multiple sensor components 5 evenly distributed on the circumference. When the ray emitting device 300 approaches the magnet 2, its electromotive force will change. The distance is different, the measured magnetic field strength is also different, and the output value changes accordingly. The ray emitting device 300 obtains and processes the data on the Hall sensor in real time to generate corresponding position information, and sends it to the display through the communication unit for display, so that the user can adjust the position of the ray emitting device 300 in time. The intraoral receiving sensor 100 is connected to the computer client through the USB port, which is convenient for displaying the captured detection pictures on the computer client.

[0045] Furthermore, the mounting plate 51 is vertically fixed on the annular circuit board 4, and the detection sensors 52 are installed on the mounting plate 51 and the annular circuit board 4 in groups of a predetermined number. The detection sensors 52 of each sensing component 5 are correspondingly distributed in the six coordinate directions of the three-dimensional coordinate system, wherein the three-dimensional coordinate system refers to a three-dimensional space XYZ coordinate system established with the circumferential center of the annular circuit board 4 as the origin, the axial direction of the annular circuit board 4 as the Y-axis, the horizontal direction perpendicular to the Y-axis as the X-axis, and the diameter direction vertically perpendicular to the Y-axis as the Z-axis. The six coordinate directions of the three-dimensional space correspond to the extension directions of the X-axis, Y-axis, and Z-axis.

[0046] Furthermore, the number of sensor assemblies 5 is at least three. When there are three sensor assemblies 5, the angle formed by adjacent sensor assemblies 5 on the annular circumference of the annular circuit board 4 is 120 degrees. When there are four sensor assemblies 5, the angle formed by adjacent sensor assemblies 5 on the annular circumference of the annular circuit board 4 is 90 degrees. Similarly, the number of sensor assemblies 5 can be adjusted according to actual conditions. In this embodiment, there are three sensor assemblies 5, each of which includes two mounting plates 51, one of which has a length parallel to the X-axis of the three-dimensional coordinate system, the other of which has a length parallel to the Z-axis of the three-dimensional coordinate system, and the height of the mounting plates 51 is perpendicular to the annular circuit board 4. The mounting plates 51 have two mounting surfaces, and the detection sensors 52 are mounted in groups of two on different mounting surfaces of the mounting plates 51.

[0047] Furthermore, the mounting plate 51 can also be set in an L shape, so that a part of the L-shaped mounting plate is parallel to the X-axis direction of the above-mentioned three-dimensional coordinate system, and the other part of the L-shaped mounting plate is parallel to the Z-axis direction of the above-mentioned three-dimensional coordinate system, thereby forming the orientation of the above-mentioned two mounting plates 51.

[0048] Furthermore, the above-mentioned sensor components 5 are evenly distributed on the annular circumference of the annular circuit board 4 at a certain circumferential angle. In a specific implementation, the sensor components 5 may not be evenly distributed at a certain circumferential angle. For example, the angle between sensor component 1 and sensor component 2 on the circumference is 90 degrees, the angle between sensor component 2 and sensor component 3 on the circumference is 120 degrees, and the angle between sensor component 3 and sensor component 1 on the circumference is 150 degrees. When the sensor components 5 are not evenly distributed on the annular circumference, the algorithm stored in the data processing unit should be adjusted accordingly.

[0049] Specifically, each sensor assembly 5 includes six detection sensors 52, which are mounted on a mounting surface of a mounting plate 51 parallel to the X-axis direction of the three-dimensional coordinate system, a mounting surface of a mounting plate 51 parallel to the Z-axis direction of the three-dimensional coordinate system, and both side surfaces of the annular circuit board 4. The two side surfaces of the annular circuit board 4 are parallel to the height direction of the mounting plate 51. After the detection sensors 52 are installed, the orientation of each detection sensor 52 corresponds to the coordinate direction of the three-axis coordinate system established with the center of the circle of the annular circuit board 4 as the center point. By vertically arranging the mounting plate 51 on the annular circuit board 4 and arranging the detection sensors 52 in predetermined numbers on the mounting plate 51 and the annular circuit board 4, the detection sensors 52 are distributed in corresponding coordinate directions of the three-dimensional coordinate system, thereby enabling the sensor assembly 5 to accurately detect the relative position of the receiving sensor in three-dimensional space.

[0050] Obviously, the embodiments described above are only some of the embodiments of the present application, rather than all of the embodiments. The preferred embodiments of the present application are given in the accompanying drawings, but they do not limit the patent scope of the present application. The present application can be implemented in many different forms. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive. Although the present application has been described in detail with reference to the aforementioned embodiments, for those skilled in the art, it is still possible to modify the technical solutions described in the aforementioned specific embodiments, or to make equivalent replacements for some of the technical features therein. Any equivalent structure made using the contents of the present application specification and the accompanying drawings, directly or indirectly used in other related technical fields, is also within the scope of patent protection of the present application.

Claims

1. An intraoral receiving sensor, characterized in that: The intraoral receiving sensor (100) comprises a housing (1), a photosensitive component (200) and a magnet (2); the photosensitive component (200) is arranged in the housing (1) and is used to receive X-rays emitted by a ray emitting device (300) to form a detection image; the magnet (2) is used in conjunction with the ray emitting device (300) to position the intraoral receiving sensor (100).

2. The intraoral receiving sensor according to claim 1, wherein: The magnet (2) is arranged outside the housing (1).

3. The intraoral receiving sensor according to claim 2, wherein: The housing (1) is provided with a protective sleeve (3) on its outer shell, the protective sleeve (3) is provided with a protective cavity (31), the magnet (2) is arranged in the protective cavity (31), and the housing (1) is partially inserted into the protective cavity (31).

4. The intraoral receiving sensor according to claim 3, wherein: The protective cover (3) is provided with a positioning groove (32).

5. The intraoral receiving sensor according to claim 3, wherein: The photosensitive component (200) is connected to a wire (400), and the protective cover (3) is provided with a through hole (33) for the wire (400) to pass through.

6. The intraoral receiving sensor according to claim 1, wherein: The magnet (2) is arranged in the housing (1).

7. The intraoral receiving sensor according to claim 6, wherein: The housing (1) is provided with a receiving cavity (11) for receiving the photosensitive component (200) and the magnet (2), and the magnet (2) is fixed on the bottom wall of the receiving cavity (11).

8. The intraoral receiving sensor according to any one of claims 1 to 7, characterized in that: The photosensitive component (200) comprises a stacked PCB board (6), a conversion layer (7), and a receiving layer (8); the receiving layer (8) is used to receive X-rays emitted by the ray emitting device (300) and convert them into visible light; the conversion layer (7) is used to convert the visible light into an electrical signal; the PCB board (6) is used to receive the electrical signal and convert it into a detection image output; the receiving layer (8) is arranged on an end of the conversion layer (7) away from the magnet (2).

9. The intraoral receiving sensor according to claim 8, wherein: A fixing layer (91) is further provided between the PCB board (6) and the conversion layer (7), and the conversion layer (7) is fixed to the PCB board (6) via the fixing layer (91). The photosensitive component (200) further comprises a reflecting layer (92) and a waterproof layer (93), and the waterproof layer (93) is provided between the receiving layer (8) and the reflecting layer (92).

10. An intraoral positioning system, characterized in that: The intraoral positioning system includes a ray emitting device (300) and an intraoral receiving sensor (100) as described in any one of claims 1 to 9, wherein an annular circuit board (4) is provided in the ray emitting device (300), and a position detection unit is provided on the annular circuit board (4), and the position detection unit includes at least three groups of sensor components (5) for detecting the position of the intraoral receiving sensor (100), and the sensor components (5) are arranged at intervals on the annular circumference of the annular circuit board (4).

Images