LED Display Device, LED Display System, and Position Error Measurement Method

Abstract

The present invention provides an LED display device, an LED display system, and a position error measurement method. Among them, the LED display device includes a display screen, the display screen includes a plurality of LED display modules, and a plurality of infrared marking points are arranged on the front surface of the LED display module. The plurality of infrared marking points include a first infrared marking point, a second infrared marking point, and a third infrared marking point that are not collinear. The measurement spatial physical information of the LED display module can be obtained according to the first infrared marking point, the second infrared marking point, and the third infrared marking point. The technical solution of this application can effectively solve the problem of unable to measure errors in real time in the related art.

Description

Technical Field

[0001] The present invention relates to the technical field of LED display, and in particular, to an LED display device, an LED display system, and a position error measurement method. Background Art

[0002] During the manufacturing and installation of large LED screens, the precise splicing of modules is one of the key factors, directly affecting the quality of the final visual effect. At present, the splicing operation relying on manual operation is prone to cause inconsistencies between modules, thus affecting the display effect and viewing experience of the entire screen. That is to say, the size of the splicing error between modules directly affects the display effect of the large LED screen.

[0003] In the related art, the size of the splicing error between modules is usually measured in the following ways:

[0004] (1) Measuring by camera photographing:

[0005] Using a high-resolution camera and cooperating with image processing software to measure the size of the splicing gap between modules. The camera's lens can capture detailed images of the LED physical pixel points of the modules emitting light, and the image processing software can analyze these images to accurately calculate the size of the splicing gap between modules. Since this method uses a high-resolution camera for imaging, it can measure the size of very small gaps very precisely. However, this method has the problem that the image processing calculation time is relatively long, resulting in the inability to present the data results in real time. In addition, this method can only measure the splicing error between modules within the two-dimensional plane scale, making the error measurement incomplete.

[0006] (2) Measuring using contact measurement tools:

[0007] Such as using an electronic micrometer or an electronic vernier caliper. These tools can directly measure the physical distance between modules and provide very accurate measurement data. Since the tools need to directly contact the modules, if the operation is improper, it may damage the modules. Moreover, this method cannot measure the error between modules in real time, and this measurement method cannot be implemented during the process of the modules displaying images.

[0008] Therefore, in the related field, there is a problem that the position error of the modules cannot be measured in real time. Summary of the Invention

[0009] The main object of the present invention is to provide an LED display device, an LED display system, and a position error measurement method to solve the problem of inability to measure errors in real time in the related art.

[0010] To achieve the above object, according to one aspect of the present invention, there is provided an LED display device, including a display screen, the display screen includes a plurality of LED display modules, and a plurality of infrared marking points are provided on the front surface of the LED display module. The plurality of infrared marking points include a first infrared marking point, a second infrared marking point, and a third infrared marking point that are not collinear. The measurement space physical information of the LED display module can be obtained according to the first infrared marking point, the second infrared marking point, and the third infrared marking point.

[0011] Further, the LED display module includes a lamp board, and a plurality of lamp beads are provided on the lamp board. The front surface of the lamp board forms the front surface of the LED display module. Among them, at least one of the plurality of infrared marking points is provided on the lamp board; and / or, at least one of the plurality of infrared marking points is located inside the lamp beads.

[0012] Further, the plurality of infrared marking points have a synthetic center point, and the synthetic center point is coincidentally arranged with the geometric center point of the front surface of the LED display module.

[0013] According to another aspect of the present invention, there is provided an LED display system, including an LED display device and a plurality of infrared cameras. The LED display device is the above-mentioned LED display device. Among them, the plurality of infrared cameras are located on the front side of the LED display device and are arranged facing the front surface of the LED display device.

[0014] Further, each infrared marking point of the LED display device is located within the recognition range of at least two infrared cameras.

[0015] Further, the front surface of the LED display module of the LED display device is a rectangular structure. The plurality of infrared marking points on the LED display module further include a fourth infrared marking point. The first infrared marking point, the second infrared marking point, the third infrared marking point, and the fourth infrared marking point are respectively located at the corners of the front surface of the LED display module, and the first infrared marking point, the second infrared marking point, the third infrared marking point, and the fourth infrared marking point are all located within the recognition range of at least three infrared cameras.

[0016] According to another aspect of the present invention, there is provided a position error measurement method for measuring the position error of the LED display module of the LED display device in the above-mentioned LED display system. The position error measurement method includes: establishing a three-dimensional coordinate system with a preset point on the front side of the display screen of the LED display device as the origin; identifying a plurality of infrared marking points of the LED display module and obtaining the measurement space physical information of the LED display module according to the space physical information of the plurality of infrared marking points in the three-dimensional coordinate system; obtaining the position error of the LED display module according to the measurement space physical information.

[0017] Further, the steps of establishing a three-dimensional coordinate system with a preset point on the front side of the display screen of the LED display device as the origin include: setting the optimal viewing position of the display screen as the preset point; and / or, the three-dimensional coordinate system includes an X-axis, a Y-axis, and a Z-axis that are perpendicular to each other. The steps of measuring spatial physical information including measuring position information and measuring angle information, and identifying multiple infrared marker points of the LED display module and obtaining the measured spatial physical information of the LED display module based on the spatial physical information of the multiple infrared marker points in the three-dimensional coordinate system include: obtaining the measurement position information and the measurement angle information according to the relative positions of each infrared marker point with the X-axis, with the Y-axis, and with the Z-axis. Among them, the measurement position information includes the distances between the combined center point of the multiple infrared marker points and the X-axis, the Y-axis, and the Z-axis, and the measurement angle information includes the rotation angles of the combined center point of the multiple infrared marker points around the X-axis, around the Y-axis, and around the Z-axis.

[0018] Further, the steps of obtaining the position error of the LED display module according to the measured spatial physical information include: subtracting the measured spatial physical information from the preset spatial physical information of the LED display module to obtain the position error of the LED display module.

[0019] Further, after the steps of obtaining the position error of the LED display module according to the measured spatial physical information, the position error measurement method further includes: comparing the position error with the preset threshold of the LED display module; when the position error is greater than or equal to the preset threshold, adjusting the position or posture of the LED display module; when the position error is less than the preset threshold, adjusting the display screen of the LED display module.

[0020] Applying the technical solution of the present invention, the LED display device includes a display screen for realizing the function of displaying images. The display screen includes a plurality of LED display modules, and the plurality of LED display modules are spliced to form the display screen. A plurality of infrared marking points are provided on the front surface of the LED display module. The plurality of infrared marking points include a first infrared marking point, a second infrared marking point, and a third infrared marking point that are not collinear. The first infrared marking point, the second infrared marking point, and the third infrared marking point can all be recognized. According to the first infrared marking point, the second infrared marking point, and the third infrared marking point, the measured spatial physical information of the LED display module can be obtained. By means of the measured spatial physical information, the position or posture of the LED display module can be judged, etc., so as to reflect the splicing situation of the display screen. Compared with the method of measuring the error between adjacent LED display modules by taking pictures or contacting measuring tools in the related art, when using the LED display device of the present application, the measured spatial physical information of the LED display module can be obtained in real time during the assembly of the LED display module, so as to guide the staff to adjust the position or posture of the LED display module. In addition, since the infrared marking points can still be recognized when the LED display device is displaying images, that is, the measured spatial physical information of the LED display module can be obtained in real time when the LED display device is displaying images, so as to adjust each LED display module in different ways (for example, adjusting the position or posture of the LED display module, or adjusting the display image of the LED display module). Therefore, the technical solution of the present application can effectively solve the problem of unable to measure errors in real time in the related art. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings forming a part of this application are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0022] Figure 1 A three-dimensional structure schematic diagram showing a partial structure of a first embodiment of an LED display device according to the present invention;

[0023] Figure 2 Shows Figure 1 A front view schematic diagram of a partial structure of the LED display device;

[0024] Figure 3 Shows Figure 1 An enlarged schematic diagram of the light board of the LED display module of the LED display device;

[0025] Figure 4 An enlarged schematic diagram of the light board of the LED display module of a second embodiment of the LED display device according to the present invention;

[0026] Figure 5shows Figure 4 an enlarged schematic view of the lamp bead

[0027] Figure 6 shows a three-dimensional structural schematic diagram of an embodiment of an LED display system according to the present invention

[0028] Figure 7 shows a flowchart of an embodiment of a position error measurement method according to the present invention

[0029] Figure 8 shows Figure 7 an alternative process of the position error measurement method Figure 1 ;

[0030] Figure 9 shows Figure 7 an alternative process of the position error measurement method Figure 2 ;

[0031] Figure 10 shows Figure 7 an alternative process of the position error measurement method Figure 3 ;

[0032] Figure 11 shows Figure 7 an alternative process of the position error measurement method Figure 4 .

[0033] Among them, the above-mentioned drawings include the following reference numerals:

[0034] 10, display screen; 11, LED display module; 111, lamp board; 112, lamp bead; 113, infrared marking point; 114, synthesis center point; 20, infrared camera Detailed Embodiment

[0035] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and in no way constitutes a limitation on the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention

[0036] As Figures 1 to 3As shown in the figure, the present application provides an LED display device. The first embodiment of the LED display device of the present application includes a display screen 10. The display screen 10 includes a plurality of LED display modules 11. A plurality of infrared marking points 113 are provided on the front surface of the LED display module 11. The plurality of infrared marking points 113 include a first infrared marking point, a second infrared marking point, and a third infrared marking point that are not collinear. The measurement space physical information of the LED display module 11 can be obtained based on the first infrared marking point, the second infrared marking point, and the third infrared marking point.

[0037] Applying the technical solution of this embodiment, the LED display device includes a display screen 10. The display screen 10 is used to implement the function of displaying a picture. The display screen 10 includes a plurality of LED display modules 11. The plurality of LED display modules 11 are spliced to form the display screen 10. A plurality of infrared marking points 113 are provided on the front surface of the LED display module 11. The plurality of infrared marking points 113 include a first infrared marking point, a second infrared marking point, and a third infrared marking point that are not collinear. The first infrared marking point, the second infrared marking point, and the third infrared marking point can all be recognized. The measurement space physical information of the LED display module 11 can be obtained based on the first infrared marking point, the second infrared marking point, and the third infrared marking point. The position or posture of the LED display module 11 and other situations can be judged based on the measurement space physical information, thereby reflecting the splicing situation of the display screen 10. Compared with the method of measuring the error between adjacent LED display modules by taking pictures or contacting measuring tools in the related art, when using the LED display device of this embodiment, the measurement space physical information of the LED display module 11 can be obtained in real time during the assembly of the LED display module, so as to guide the staff to adjust the position or posture of the LED display module 11; in addition, since the infrared marking point 113 can still be recognized when the LED display device displays a picture, that is, the measurement space physical information of the LED display module 11 can be obtained in real time when the LED display device displays a picture, so as to adjust each LED display module 11 in different ways (for example, adjusting the position or posture of the LED display module 11, or adjusting the display picture of the LED display module 11). Therefore, the technical solution of this embodiment can effectively solve the problem of inability to measure errors in real time in the related art.

[0038] Compared with the method of camera photographing measurement in the related art, by measuring a plurality of infrared marking points 113 on the LED display device of this embodiment to obtain the measurement space physical information of the LED display module 11, the calculation amount is greatly reduced, and thus real-time measurement can be realized.

[0039] It should be noted that during the operation of the LED display device, due to the heat generated by itself or the influence of environmental factors, the LED display module 11 of the display screen 10 may undergo slight changes in position or attitude, resulting in changes in the splicing gaps between the LED display modules 11 and affecting the picture display effect of the LED display device. In addition, with the continuous development of LED display technology, the display screen 10 in a static state may no longer meet the display needs of users. According to various application scenarios such as stage performances, flight simulations, and VR interactions, more flexible and variable movable screens have emerged. The movable screen is also a type of display screen. When the movable screen is working, various states such as separation, re-splicing, and re-combination of the LED display modules will occur. At this time, the splicing gaps between the LED display modules 11 will also change.

[0040] The changes in the position or attitude of the LED display module 11 during the operation of the above-mentioned display screen 10 and the emergence of the movable screen pose higher requirements for the measurement of the splicing seams between the LED display modules 11, that is, to measure the splicing seams between the LED display modules 11 in real time. Obviously, the measurement methods in the related technologies cannot meet the above requirements.

[0041] The LED display device applying this embodiment can obtain the physical information of the measurement space of the LED display module 11 in real time during the operation of the LED display device, so as to achieve the effect of real-time measurement error. The "physical information of the measurement space" can include measurement position information or measurement angle information (specific descriptions are provided later), which is used to more comprehensively characterize the position and attitude of the LED display module, so as to make the position measurement of the LED display module more accurate. In addition, the "first infrared marking point, second infrared marking point, and third infrared marking point that are not collinear" refers to: among the first infrared marking point, second infrared marking point, and third infrared marking point, the connection line of any two infrared marking points will not pass through the remaining one infrared marking point. By setting at least three infrared marking points, a comprehensive measurement of the position and attitude of the LED display module can be achieved. If only one infrared marking point is set on the front surface of the LED display module, only the measurement position information of the LED display module can be obtained, and the measurement angle information of the LED display module cannot be obtained (for example, when the LED display module rotates around this infrared marking point, the position of this infrared marking point remains unchanged); if only two infrared marking points are set on the front surface of the LED display module or three collinear infrared marking points are set, the rotation of the LED display module around the straight line where the two / three infrared marking points are located cannot be obtained (for example, when the LED display module rotates around this straight line, the positions of the two / three infrared marking points remain unchanged).

[0042] As Figure 3As shown in the figure, the LED display module 11 includes a lamp board 111, on which a plurality of lamp beads 112 are arranged. The front surface of the lamp board 111 forms the front surface of the LED display module 11. At least one of the plurality of infrared marking points 113 is arranged on the lamp board 111. With such an arrangement, the infrared marking points 113 are easier to be recognized, and at the same time, it does not affect the light emission of the lamp beads 112 and the normal display of the lamp board 111. The wavelength of the infrared marking points 113 is about 850 nm, which has the advantage of high sensitivity. The infrared light emitted by these infrared marking points 113 is invisible to human eyes and conventional cameras, and can only be detected by special devices (such as infrared cameras). This design ensures that the full-color display of the display screen 10 is not affected in any way, and at the same time provides an accurate module positioning function.

[0043] In addition, in this embodiment, the plurality of infrared marking points have a synthetic center point 114, and the synthetic center point 114 is arranged to coincide with the geometric center point of the front surface of the LED display module 11. With such an arrangement, the processing of the physical information of the measurement space will be simpler.

[0044] In addition, as Figure 4 and Figure 5 shown in the figure, the present application also provides a second embodiment of the LED display device. The difference between the second embodiment and the first embodiment is that at least one of the plurality of infrared marking points 113 is located inside the lamp bead 112. That is to say, in this embodiment, the infrared marking points 113 are integrated inside the lamp beads 112, so that there is no need to separately weld the infrared marking points 113 on the lamp board 111. Whether it is the infrared marking points in the first embodiment or the second embodiment, they can emit infrared light by setting light-emitting diodes or other light sources inside the infrared marking points through active active light-emitting technology. Such active infrared marking points can emit infrared spectra with specific frequencies to be consistent with the capture frequency of the capture device (such as the infrared camera mentioned later), so that the capture device can capture specific infrared marking points without causing confusion. On the premise of not sacrificing aesthetics and space efficiency, by integrating and packaging the infrared LED chip inside a single RGB LED chip, the space can be effectively saved, the appearance of the module is not changed, the whole module becomes more compact, and the overall aesthetics and design coherence of the LED display device are maintained. In other embodiments, some of the infrared marking points are arranged on the lamp board, and some of the infrared marking points are integrated inside the lamp beads.

[0045] As Figure 6As shown in the figure, the present application also provides an LED display system. The LED display system of the present application includes an LED display device and a plurality of infrared cameras 20. The plurality of infrared cameras 20 are located on the front side of the LED display device and are arranged facing the front surface of the LED display device. Among them, the LED display device is the above-mentioned LED display device. The above-mentioned LED display device can effectively solve the problem of unable to measure errors in real time in the related art. The LED display system with the above-mentioned LED display device also has the above-mentioned advantages.

[0046] In addition, in this embodiment, each infrared marking point 113 of the LED display device is located within the recognition range of at least two infrared cameras 20. Specifically, if only one infrared camera 20 recognizes the infrared marking point 113, only the two-dimensional coordinates of the infrared marking point 113 can be obtained. As set above, by using at least two infrared cameras 20 to recognize the infrared marking point 113, the three-dimensional coordinates of the infrared marking point 113 can be obtained, and then the measurement position information and measurement angle information of the physical information of the measurement space can be obtained through the three-dimensional coordinates of a plurality of infrared marking points 113.

[0047] As Figures 1 to 6 shown, the front surface of the LED display module 11 of the LED display device is a rectangular structure. The plurality of infrared marking points 113 on the LED display module 11 include a fourth infrared marking point. The first infrared marking point, the second infrared marking point, the third infrared marking point, and the fourth infrared marking point are respectively located at the corners of the front surface of the LED display module 11. The first infrared marking point, the second infrared marking point, the third infrared marking point, and the fourth infrared marking point are all located within the recognition range of at least three infrared cameras 20. Specifically, the physical information of the measurement space of the LED display module 11 can be obtained through the four infrared recognition points arranged at the four corners of the rectangular structure. Each infrared recognition point is recognized by at least three infrared cameras 20, which can make the reference data of the infrared recognition point more, so that the three-dimensional coordinates of the infrared recognition point can be obtained more accurately through more reference data, avoiding occlusion and blind spots, and ensuring that the infrared marking point 113 can be recognized under any circumstances. Each infrared marking point can be recognized by the same three infrared cameras or by different three infrared cameras.

[0048] Four infrared marking points are fixedly installed on each module. The relative positions of these infrared marking points remain unchanged, forming a stable geometric configuration. By regarding the geometric center (i.e., the synthetic center point) of these four infrared marking points as the center point of the module, we can consider the module as a rigid body with a stable structure and not easily deformed. The infrared camera 20 can monitor and record the three-dimensional spatial positions of these infrared marking points in real time, thereby obtaining the position of the center point of the module rigid body and the data of the rotation angles (x, y, z, α, β, γ). These data directly correspond to the position and attitude of the module itself, ensuring the consistency between the measured data and the actual situation of the module. In this way, the precise measurement and calibration of the entire display screen 10 can be achieved, ensuring the accuracy of the display screen 10 splicing and the optimization of the display effect. The infrared camera 20 needs to calibrate the coordinate system regularly to compensate for the measurement deviation caused by environmental changes (such as temperature, humidity, displacement, vibration) to ensure the continuous accuracy of the measured data.

[0049] For the data of the same infrared marking point captured by multiple infrared cameras 20, three-dimensional reconstruction is carried out, and the spatial coordinates of the infrared marking point are calculated by the triangulation method. It is planned to adopt a weighted average algorithm, combined with the measurement confidence of each infrared camera 20, to reduce the influence of the error of the data of a single infrared camera 20 on the overall measurement result.

[0050] Error analysis:

[0051] A. Two-dimensional recognition error:

[0052] In the image processing method for the recognition of the infrared camera 20 on the two-dimensional image, by optimizing the gradient calculation and interpolation technology, the positioning error is reduced to the sub-pixel level, within the range of ±0.1 pixel. By using a higher-resolution infrared camera (such as 4K and above), the actual measurement error can be effectively reduced. For example, if the area range covered by the lens for the LED is 5000 mm wide, then the two-dimensional accuracy range is: 5000 mm / (3840 / 0.1) = 0.13 mm.

[0053] B. Three-dimensional coordinate calculation error;

[0054] From the fusion calculation of the two-dimensional images of multiple infrared cameras, through high-precision calibration and data fusion technology, the error will be further reduced. The position error range of the coordinates of the three-dimensional reconstruction is set to ±0.1 mm. The rotation angle error mainly depends on the position error of the coordinates and the geometric layout of the infrared marking points. The relationship between the rotation angle error (Δθ) and the position error (δd) can be approximately expressed by the following formula: Δθ≈δd / L; where: L is the characteristic length between the infrared marking points (i.e., the distance between the infrared marking points of the LED display module).

[0055] In this embodiment, the four infrared marking points of each module are arranged at the four corners of the module, and the characteristic length L (i.e., the average distance between the infrared marking points) is 200 mm. Then: Δθ≈0.1mm / 200mm = 0.0005 radians ≈ 0.03°. Therefore, the range of the rotation angle error is about ±0.03°.

[0056] In addition, in other embodiments, a protective cover is provided outside the infrared marking points to prevent dust, water vapor, etc. from affecting their optical performance and ensure long-term stable recognition effects. The infrared marking points and the lamp beads share a heat dissipation structure to ensure that the infrared marking points maintain a stable operating temperature during long-term operation and prevent performance fluctuations and increased errors caused by overheating.

[0057] As Figure 7 shown, the present application also provides a position error measurement method. The position error measurement method of the present application is used to measure the position error of the LED display module 11 of the LED display device of the LED display system, where the LED display system is the above-mentioned LED display system. The above-mentioned LED display system can effectively solve the problem of unable to measure errors in real time in the related art, and the position error measurement method for measuring the LED display module 11 of the LED display device of the above-mentioned LED display system also has the above-mentioned advantages.

[0058] Specifically, the position error measurement method includes:

[0059] Step S10: Establish a three-dimensional coordinate system with a preset point on the front side of the display screen 10 of the LED display device as the origin;

[0060] Step S20: Identify multiple infrared marking points 113 of the LED display module 11 and obtain the measured spatial physical information of the LED display module 11 according to the spatial physical information of the multiple infrared marking points 113 in the three-dimensional coordinate system;

[0061] Step S30: Obtain the position error of the LED display module 11 according to the measured spatial physical information.

[0062] Specifically, by establishing a unified three-dimensional coordinate system, all the LED display modules 11 of the display screen 10 are measured under this three-dimensional coordinate system. In this way, not only can the relative error between each LED display module 11 and its adjacent LED display module 11 be compared, but also the splicing quality of the entire display screen 10 can be comprehensively characterized. The position error measurement method of this embodiment is superior to the measurement methods in the related art, and the latter usually only focuses on the relative error between two adjacent LED display modules and cannot comprehensively reflect the splicing situation of the entire display screen.

[0063] As Figure 8As shown, the steps of establishing a three-dimensional coordinate system with a preset point on the front side of the display screen 10 of the LED display device (i.e., step S10) include:

[0064] Step S11: Set the optimal viewing position of the display screen 10 as the preset point.

[0065] It should be noted that the "optimal viewing position of the display screen 10" refers to the position where the viewer can experience the best visual effects and image quality. This position is usually related to the size, resolution, viewing angle characteristics of the display screen 10, and the nature of the content playback. In this embodiment, the optimal viewing position is defined by the viewing angle and viewing distance. The optimal viewing position is affected by the viewing angle (i.e., the angle formed between the viewer's eyes and the screen edge) and the viewing distance (the distance between the viewer's eyes and the center of the screen). For the optimal viewing position of the display screen 10, the viewing angle is usually between 30° and 40° horizontally. The optimal viewing distance is generally 2 to 3 times the height of the display screen 10. If the viewing distance is too close, the pixel structure may be seen, affecting the continuity and clarity of the image; if the viewing distance is too far, the high-resolution details of the display screen 10 may not be fully appreciated.

[0066] As Figure 9 shown, the three-dimensional coordinate system includes an X-axis, a Y-axis, and a Z-axis that are perpendicular to each other. Measuring spatial physical information includes measuring position information and measuring angle information.

[0067] The steps of identifying multiple infrared marker points 113 of the LED display module 11 and obtaining the measured spatial physical information of the LED display module 11 based on the spatial physical information of the multiple infrared marker points 113 in the three-dimensional coordinate system (i.e., step S20) include:

[0068] Step S21: Obtain the measurement position information and the measurement angle information according to the relative positions of each infrared marker point 113 with the X-axis, the Y-axis, and the Z-axis. Among them, the measurement position information includes the distances between the combined center point 114 of the multiple infrared marker points 113 and the X-axis, the Y-axis, and the Z-axis, and the measurement angle information includes the rotation angles of the combined center point 114 of the multiple infrared marker points 113 around the X-axis, around the Y-axis, and around the Z-axis.

[0069] Specifically, first, the distance data and rotation angle data of each infrared marker point 113 are measured, and then the distance data and rotation angle data of the composite center point 114 formed by multiple infrared marker points 113 are calculated. The data of the composite center point 114 characterize the measurement position information and measurement angle information, and the measurement position information and measurement angle information are used to characterize the measurement space physical information of the LED display module 11. Compared with the related technology that only uses two-dimensional data for characterization, the measurement space physical information measured in this embodiment can more comprehensively characterize the position state and attitude state of the LED display device, thereby making the measurement error more accurate.

[0070] As Figure 10 shown, the steps for obtaining the position error of the LED display module 11 according to the measurement space physical information (i.e., step S30) include:

[0071] Step S31: Subtract the measurement space physical information from the preset space physical information of the LED display module 11 to obtain the position error of the LED display module 11.

[0072] Specifically, the "preset space physical information of the LED display module 11" refers to the designed position state and attitude state of each LED display module 11 of the LED display device in the ideal state. If the measurement space physical information of the LED display module 11 is closer to the preset space physical information, it means that the LED display module 11 is closer to the designed position state and attitude state in the ideal state. Subtracting the measurement space physical information from the preset space physical information to characterize the position error of the LED display module 11.

[0073] As Figure 11 shown, in this embodiment, after step S31: the step of subtracting the measurement space physical information from the preset space physical information of the LED display module 11 to obtain the position error of the LED display module 11, the position error measurement method further includes:

[0074] Step S32: Compare the position error with the preset threshold of the LED display module 11;

[0075] Step S33: When the position error is greater than or equal to the preset threshold, adjust the position or attitude of the LED display module 11;

[0076] Step S34: When the position error is less than the preset threshold, adjust the display screen of the LED display module 11.

[0077] Specifically, when the position error is less than a preset threshold, that is, the position error is small at this time, only by adjusting the display screen of the LED display module 11 can the influence of this error be eliminated. When the position error is greater than or equal to the preset threshold, that is, the position error is large at this time, simply adjusting the display screen of the LED display module 11 can no longer significantly eliminate the influence of this error on the display. Then, the position or posture of the LED display module 11 is adjusted to reduce this error (it should be noted that in other embodiments, it is also possible to use other comparison methods to obtain the position error of the LED display module by measuring the physical information of the space and the preset physical information of the space).

[0078] It should be noted that the steps of adjusting the display screen of the LED display module 11 include:

[0079] Step S1: Obtain the image to be displayed, where the image to be displayed is the image to be displayed on the display screen 10;

[0080] Step S2: Determine the offsets corresponding to the respective LED display modules 11;

[0081] Step S3: Based on the image to be displayed, determine the initial sub-images corresponding to the respective LED display modules 11;

[0082] Step S4: Based on the offsets corresponding to the respective LED display modules 11, correct the initial sub-images corresponding to the respective LED display modules 11 to obtain the target sub-images corresponding to the respective LED display modules 11;

[0083] Step S5: Based on the target sub-images corresponding to the respective LED display modules 11, determine the target display image so that the display screen 10 displays according to the target display image.

[0084] Specifically, in step S1, the image to be displayed is obtained.

[0085] Among them, the image to be displayed is involved. The image to be displayed is the image used for display on the display screen 10, which can be a static picture or a dynamic video, and can be the image data directly received from the image source.

[0086] Among them, the display screen 10 is involved. The display screen 10 is the display screen 10 used for displaying the image to be displayed and having a certain splicing error, such as the display screen 10 with a splicing accuracy index lower than the predetermined threshold, the display screen 10 that needs to be corrected for splicing error. For example, the display screen 10 with poor display effect due to splicing error.

[0087] Among them, multiple LED display modules 11 are involved. The multiple LED display modules 11 are used to display a part of the image to be displayed and constitute the basic unit of the display screen 10. The display screen 10 can be formed by splicing multiple LED display modules 11. For example, by splicing LED display modules 11, a larger display screen 10 can be formed.

[0088] During the installation or on-site use of the display screen 10, there is a deviation in the splicing position between the multiple LED display modules 11, which leads to visual inconsistency of the display screen 10, affecting the viewing experience. However, considering the unavoidability of splicing errors, it is necessary to obtain the image to be displayed on the display screen 10, so as to provide the necessary data basis for the subsequent establishment of the display relationship between the display screen 10 and the image to be displayed on the display screen 10, so as to compensate for the problem of poor display effect of the display screen 10 caused by the position error based on this display relationship.

[0089] It should be noted that there is no specific limitation on the method of obtaining the image to be displayed, and the method can be customized according to the actual application and scenario.

[0090] In step S2 , the offsets corresponding to the plurality of LED display modules 11 are determined.

[0091] The offset is involved, and the offset is the deviation between the current positions and the target positions respectively corresponding to the plurality of LED display modules 11 during the splicing process, and can be the deviation of the coordinate value and the deviation of the rotation angle.

[0092] Since the display screen 10 is composed of multiple LED display modules 11, and the splicing errors corresponding to each LED display module 11 are different, by determining the offsets corresponding to the multiple LED display modules 11, subsequent error correction can be carried out in a targeted manner according to the specific errors of each LED display module 11, thereby improving the accuracy of the image displayed on the display screen 10, ensuring the consistency of the display effect of the calibrated display screen 10, and enhancing the user's viewing experience.

[0093] In step S3: according to the image to be displayed, initial sub-images corresponding to the plurality of LED display modules 11 are determined;

[0094] The initial sub-image is involved. The initial sub-image is determined before correction according to the size of the corresponding LED display module 11 and the image to be displayed, and is the initial sub-image that each LED display module 11 should display.

[0095] Since the different stitching errors corresponding to each LED display module 11 will affect the display effects of the images displayed on the LED display module 11, therefore, by determining the initial sub-images respectively corresponding to multiple LED display modules 11 according to the image to be displayed, the relationship between the LED display module 11 and the corresponding sub-image is established, and then the correction of the image to be displayed can be realized in combination with the display device. Moreover, by decomposing the large image processing problem into multiple small image processing problems, and determining the initial sub-images respectively corresponding to multiple LED display modules 11, it is possible to adjust the display images on each LED display module 11 specifically while reducing the computational complexity of the display screen 10 for displaying the image to be displayed, which helps the subsequent error correction, and thus can solve the problem that the display effect of the display screen 10 is poor due to the influence of positional errors.

[0096] It should be noted that there is no specific limitation on the method for determining the initial sub-images respectively corresponding to multiple LED display modules 11, and it can be set customarily according to the actual application and scenario.

[0097] In step S4: according to the offsets respectively corresponding to multiple LED display modules 11, the initial sub-images respectively corresponding to multiple LED display modules 11 are corrected to obtain the target sub-images respectively corresponding to multiple LED display modules 11;

[0098] Among them, the target sub-image is involved. The target sub-image is the sub-image obtained by correcting the corresponding initial sub-image according to the offsets respectively corresponding to multiple LED display modules 11.

[0099] Since there are positional errors among multiple LED display modules 11 in the display screen 10, it causes problems such as misalignment, gaps or overlaps in the corresponding parts of the image to be displayed on multiple LED display modules 11 and the stitching parts between LED display modules 11. According to the previously determined offsets of multiple LED display modules 11, the initial sub-images of each LED display module 11 are corrected to generate target sub-images. This correction process can make the target sub-images smoother and more coherent, ensuring that the entire display area presents a consistent and clear image, eliminating the influence of positional errors on the image display of the display screen 10, and thus helping to improve the overall display quality and visual effect of the display screen 10 subsequently.

[0100] It should be noted that there is no specific limitation on the method for determining the target sub-images respectively corresponding to multiple LED display modules 11, and it can be set customarily according to the actual application and scenario.

[0101] In step S5: Determine the target display image according to the target sub-images corresponding to the multiple LED display modules 11 respectively, so that the display screen 10 displays according to the target display image.

[0102] Among them, the target display image is involved. The target display image is an image formed by splicing the target sub-images corresponding to the multiple LED display modules 11 and is used for actual display on the display screen 10.

[0103] Since the target sub-images corresponding to the multiple LED display modules 11 respectively are sub-images obtained by targeted correction according to the offsets of the corresponding LED display modules 11, therefore, by obtaining an overall target display image for actual display on the display screen 10 based on the multiple target sub-images, problems such as misalignment and tomography of the display images of the multiple LED display modules 11 caused by position errors are avoided, ensuring that the target display image actually displayed on the display screen 10 is a complete and coherent image, thereby improving the display effect of the display screen 10 and enhancing the comfortable viewing experience of users.

[0104] It should be noted that regarding the method of determining the target display image according to the target sub-images corresponding to the multiple LED display modules 11 respectively, no specific limitation is made here, and it can be custom-set according to actual applications and scenarios.

[0105] Through the above steps S1 - S5, the image to be displayed is obtained, where the image to be displayed is the image to be displayed on the display screen 10, and the display screen 10 includes a plurality of LED display modules 11. Determine the offsets corresponding to the plurality of LED display modules 11 respectively. According to the image to be displayed, determine the initial sub - images corresponding to the plurality of LED display modules 11 respectively. According to the offsets corresponding to the plurality of LED display modules 11 respectively, correct the initial sub - images corresponding to the plurality of LED display modules 11 respectively to obtain the target sub - images corresponding to the plurality of LED display modules 11 respectively. According to the target sub - images corresponding to the plurality of LED display modules 11 respectively, determine the target display image so that the display screen 10 displays according to the target display image. In this embodiment, based on the display screen 10 and the plurality of LED display modules 11 of this display screen 10, analyze the position error of the LED display modules 11 of the display screen 10 to determine the offsets corresponding to the plurality of LED display modules 11. By determining the initial sub - images corresponding to the plurality of LED display modules 11 respectively, the display relationship between the display screen 10 and the image to be displayed is determined, and specifically, according to the offsets corresponding to the plurality of LED display modules 11, correct the initial sub - images corresponding to the plurality of LED display modules 11 to obtain the corresponding target sub - images, making the target sub - images smoother and more coherent. And based on the corresponding target sub - images, determine the target display image for the actual display of the display screen 10, ensuring that the entire display area presents a consistent and clear image, thereby solving the technical problem in the related art that the display effect of the display screen 10 is poor due to the influence of position error.

[0106] In addition, the specific implementation steps of the position error measurement method in this embodiment are as follows:

[0107] 1) System installation and configuration:

[0108] Install infrared marking points at the four corners of each LED display module.

[0109] Arrange a plurality of infrared cameras to ensure coverage of the entire area of the display screen.

[0110] Connect the infrared cameras to the software system for initial calibration.

[0111] 2) System startup and calibration:

[0112] Start the system, perform geometric calibration of the infrared cameras, and confirm that the internal and external parameters of all infrared cameras are accurate.

[0113] Determine the coordinate origin, calibrate the three - dimensional coordinate system to ensure the accuracy and stability of the three - dimensional coordinate system.

[0114] 3) Real - time data acquisition and processing:

[0115] The infrared camera captures the images of the infrared marker points of each LED display module in real time.

[0116] Through the image processing algorithm, the two-dimensional coordinates of the infrared marker points are extracted.

[0117] Based on the three-dimensional coordinates of multiple infrared marker points on the LED display module, the synthetic center point is obtained, and the physical information of the measurement space of the synthetic center point is calculated.

[0118] 4) Error calculation and adjustment:

[0119] Compare the physical information of the measurement space with the preset physical information, and calculate the position error of the LED display module.

[0120] If the position error is greater than or equal to the preset threshold, an adjustment instruction is automatically generated, a notification report is issued, and the position and attitude of the LED display module are finely adjusted; if the position error is less than the preset threshold, the display screen of the LED display module is adjusted.

[0121] Repeat the measurement until the position errors of all LED display modules are within the allowable range.

[0122] 5) System maintenance and optimization:

[0123] Regularly check the working status of the infrared marker points and the infrared camera to ensure the long-term stable operation of the LED display system.

[0124] According to the actual usage situation, optimize the layout and calibration parameters of the infrared camera to improve the measurement accuracy and efficiency.

[0125] In summary, during the manufacturing and installation process of the LED large screen, the precise splicing of the LED display modules is one of the key factors, directly affecting the final visual effect. Currently, the operation of splicing modules relying on manual operation is difficult to achieve the ideal high precision, easily leading to inconsistencies between LED display modules, thus affecting the display effect and viewing experience of the entire screen. In addition, for the position error of the LED display module, the existing measurement technologies usually involve physical contact, which may cause damage to the LED display module and cannot monitor this error in real time. Therefore, it is particularly important to develop a system and method that can detect the errors between LED display modules in real time, accurately, and comprehensively.

[0126] In existing LED display module error measurement technologies, a common practice is to measure the horizontal and vertical offset errors (i.e., two-dimensional errors) between modules to ensure the overall visual coherence and flatness of the screen. However, this method has certain limitations because it ignores the possible front-to-back displacements and rotational errors (α, β, γ angles) around each axis (X, Y, Z axes) between LED display modules, and these errors also affect the display effect and viewing experience of the screen.

[0127] Traditional measurement technologies usually rely on simple physical measuring tools or methods based on two-dimensional image processing, and these methods often fall short when dealing with complex three-dimensional spatial positioning problems. Especially for large LED display devices, due to the large number of LED display modules and various factors in the installation environment, simply focusing on the horizontal and vertical offsets is no longer sufficient to meet the high-quality splicing requirements.

[0128] To overcome these limitations, a technology capable of comprehensively measuring the offset and rotational errors between LED display modules is needed. This technology should be able to accurately measure the positions of LED display modules in three-dimensional space (in the X, Y, Z axis directions) and their rotational angles relative to each other (α around the X axis, β around the Y axis, γ around the Z axis). Such all-round measurement can not only provide more accurate splicing data but also help workers quickly identify and correct errors occurring during the splicing process, thus ensuring the best display effect and the longest service life of the LED display device.

[0129] In the embodiment of the LED display device of the present application, by installing actively driven infrared LED lights (i.e., infrared marker points 113) at the four corners of each LED display module and using multiple infrared tracking cameras (i.e., infrared cameras 20) to capture these infrared LED lights in real time, the purpose of non-contact measurement and accurate calculation of the spatial position and angle (x, y, z, α, β, γ) of each module is achieved. This not only improves the splicing accuracy, reduces the visual tearing and separation effects, but also avoids potential damage to the modules caused by physical measurement, realizes real-time monitoring of the overall screen splicing quality without affecting the normal display function of the screen, and provides necessary data support for immediate adjustment.

[0130] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by orientation words such as "front, back, up, down, left, right", "horizontal, vertical, perpendicular, horizontal" and "top, bottom", etc. is usually based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description. Without contrary instructions, these orientation words do not indicate and imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation on the protection scope of the present invention; the orientation words "inside, outside" refer to the inside and outside relative to the contour of each component itself.

[0131] In addition, it should be noted that the use of words such as "first", "second", etc. to limit components is only for the convenience of distinguishing the corresponding components. Without additional statements, the above words have no special meaning. Therefore, it should not be construed as a limitation on the protection scope of the present invention.

[0132] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A position error measurement method, characterized in that: Used to measure the position error of an LED display module (11) of an LED display device of an LED display system, the LED display system comprising the LED display device and a plurality of infrared cameras (20), wherein the plurality of infrared cameras (20) are located at the front side of the LED display device and are arranged toward the front surface of the LED display device, the LED display device comprising a display screen (10), the display screen (10) comprising a plurality of the LED display modules (11), a plurality of infrared marking points (113) being arranged on the front surface of the LED display module (11), the plurality of infrared marking points (113) comprising a first infrared marking point, a second infrared marking point and a third infrared marking point which are arranged non-collinearly, and physical information of the measurement space of the LED display module (11) can be obtained according to the first infrared marking point, the second infrared marking point and the third infrared marking point; The position error measurement method comprises: Establishing a three-dimensional coordinate system with a preset point on the front side of the display screen (10) of the LED display device as the origin; Identifying a plurality of the infrared marking points (113) of the LED display module (11) and obtaining measurement space physical information of the LED display module (11) based on the space physical information of the plurality of the infrared marking points (113) in the three-dimensional coordinate system; Obtaining a position error of the LED display module (11) according to the physical information of the measurement space; The three-dimensional coordinate system comprises an X-axis, a Y-axis and a Z-axis which are perpendicular to each other, the measurement space physical information comprises measurement position information and measurement angle information, and the step of identifying a plurality of infrared marking points (113) of the LED display module (11) and obtaining the measurement space physical information of the LED display module (11) according to the spatial physical information of the plurality of infrared marking points (113) in the three-dimensional coordinate system comprises: obtaining the measurement position information and the measurement angle information according to the relative position of each infrared marking point (113) with respect to the X-axis, the Y-axis and the Z-axis, wherein the measurement position information comprises the distance between a synthetic center point (114) of the plurality of infrared marking points (113) and the X-axis, the Y-axis and the Z-axis, and the measurement angle information comprises the rotation angle of the synthetic center point (114) of the plurality of infrared marking points (113) around the X-axis, the Y-axis and the Z-axis.

2. The position error measurement method according to claim 1, characterized in that: The step of establishing a three-dimensional coordinate system with a preset point on the front side of the display screen (10) of the LED display device as the origin comprises: setting the best viewing position of the display screen (10) as the preset point.

3. The position error measurement method according to claim 1, characterized in that: The step of obtaining the position error of the LED display module (11) according to the physical information of the measurement space comprises: The position error of the LED display module (11) is obtained by subtracting the measurement space physical information from the preset space physical information of the LED display module (11).

4. The position error measurement method according to any one of claims 1 to 3, characterized in that: After the step of obtaining the position error of the LED display module (11) according to the physical information of the measurement space, the position error measurement method further comprises: Comparing the position error with a preset threshold value of the LED display module (11); When the position error is greater than or equal to the preset threshold, adjusting the position or posture of the LED display module (11); When the position error is less than the preset threshold, the display screen of the LED display module (11) is adjusted.

5. An LED display device, used for executing a position error measurement method, wherein the position error measurement method is the position error measurement method according to any one of claims 1 to 4, wherein the LED display device comprises a display screen (10), wherein the display screen (10) comprises a plurality of LED display modules (11), wherein: A plurality of infrared marking points (113) are arranged on the front surface of the LED display module (11), the plurality of infrared marking points (113) comprising a first infrared marking point, a second infrared marking point and a third infrared marking point which are not arranged in a co-linear manner, and physical information of the measurement space of the LED display module (11) can be obtained based on the first infrared marking point, the second infrared marking point and the third infrared marking point.

6. The LED display device according to claim 5, characterized in that: The LED display module (11) comprises a lamp board (111), a plurality of lamp beads (112) are arranged on the lamp board (111), and the front surface of the lamp board (111) forms the front surface of the LED display module (11), wherein: At least one of the plurality of infrared marking points (113) is arranged on the light board (111); and / or, At least one of the plurality of infrared marking points (113) is located inside the lamp bead (112).

7. The LED display device according to claim 5, characterized in that: The plurality of infrared marking points have a synthetic center point (114), and the synthetic center point (114) is arranged to coincide with the geometric center point of the front surface of the LED display module (11).

8. An LED display system, characterized in that: The invention comprises an LED display device and a plurality of infrared cameras (20), wherein the LED display device is the LED display device according to any one of claims 5 to 7, wherein the plurality of infrared cameras (20) are located on the front side of the LED display device and are arranged toward the front surface of the LED display device.

9. The LED display system according to claim 8, characterized in that: Each infrared marking point (113) of the LED display device is located within the recognition range of at least two of the infrared cameras (20).

10. The LED display system according to claim 8, characterized in that: The front surface of the LED display module (11) of the LED display device is a rectangular structure; the plurality of infrared marking points (113) on the LED display module (11) further include a fourth infrared marking point; the first infrared marking point, the second infrared marking point, the third infrared marking point and the fourth infrared marking point are respectively located at corners of the front surface of the LED display module (11); and the first infrared marking point, the second infrared marking point, the third infrared marking point and the fourth infrared marking point are all located within the recognition range of at least three infrared cameras (20).

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