Method of determining display pixel light cross-talk and corresponding test system

Abstract

The present application provides a method for determining light crosstalk of a display pixel, comprising the following steps: providing a display, wherein the display has a plurality of pixels; lighting a first pixel in the plurality of pixels, wherein N second pixels adjacent to the first pixel are not lighted, wherein N is a positive integer; determining brightness Vx of the first pixel and brightness of the N second pixels; determining maximum brightness Vmax in the brightness of the N second pixels; and determining a crosstalk factor Fc by the following formula: Fc=Vmax / Vx. Furthermore, the present application also provides a pixel light crosstalk test system. Through the present application, the test procedure can be simplified and the calculation amount can be reduced.

Description

Technical Field

[0001] This invention generally relates to the field of displays, and more specifically, to a method for determining pixel optical crosstalk in a display. Furthermore, this invention also relates to a pixel optical crosstalk testing system. Background Technology

[0002] A micro light-emitting diode (LED) is a novel LED structure created by thinning, miniaturizing, and arraying existing LED structures. It integrates arrayed micron-sized LED units onto an active-addressable driver panel to enable individual LED illumination and control, thereby outputting the desired display image. The core structure of a micro LED is a PN junction diode, constructed from a direct bandgap semiconductor material. When a forward bias voltage is applied to the upper and lower electrodes, allowing current to flow, electrons and holes recombine in the active region, simultaneously emitting a single-color photon.

[0003] Miniature light-emitting diodes (LEDs) have a high pixel density and a small spacing between adjacent LEDs, for example, a center-to-center distance of 2 to approximately 50 micrometers. This high-density arrangement can lead to optical crosstalk between adjacent LEDs, where light emitted from one LED enters the light of one or more adjacent LEDs. Optical crosstalk can cause abnormal brightness or color of the output light from the LEDs, which in turn can lead to abnormal brightness or color of the displayed image.

[0004] There is a need for an efficient solution to determine optical crosstalk in displays. Summary of the Invention

[0005] The objective of this invention is to provide a method and corresponding testing system for determining optical crosstalk between display pixels. This method and / or the device can simplify the testing process and reduce the computational load.

[0006] In a first aspect of the invention, this task is accomplished by a method for determining optical crosstalk in display pixels, the method comprising the following steps:

[0007] A display is provided, the display having a plurality of pixels;

[0008] Light up the first pixel among the plurality of pixels, wherein the N second pixels adjacent to the first pixel are not lit, where N is a positive integer;

[0009] Determine the brightness Vx of the first pixel and the brightness of the N second pixels;

[0010] Determine the maximum brightness Vmax among the brightness of the N second pixels; and

[0011] The crosstalk factor Fc is determined using the following formula:

[0012] Fc = Vmax / Vx.

[0013] In one embodiment of the present invention, the N second pixels comprise m pixel layers, where m is a positive integer, and the m pixel layers comprise:

[0014] The first pixel layer includes 8 pixels directly adjacent to the first pixel;

[0015] The second pixel layer includes 16 pixels that are directly adjacent to the first pixel layer;

[0016] …

[0017] The m-th pixel layer comprises 8m pixels directly adjacent to the (m-1)-th pixel layer.

[0018] In another embodiment of the present invention, the N second pixels comprise a pixel block, wherein the first pixel is one of the internal pixels of the pixel block, and the pixel block comprises one of the following:

[0019] Triangular pixel blocks, rectangular pixel blocks, diamond pixel blocks, polygonal pixel blocks, and irregularly shaped pixel blocks.

[0020] In another embodiment of the invention, the first pixel is the center pixel of the pixel block or the pixel closest to the center pixel.

[0021] In another embodiment of the present invention, determining the brightness Vx of the first pixel and the brightness of the N second pixels includes the following steps:

[0022] Capture pixel images of the display using a camera;

[0023] Identify, from the pixel image, a first image pixel corresponding to a first pixel and a second image pixel corresponding to a second pixel; and

[0024] The brightness of the first image pixel and the second image pixel are determined as the brightness of the first pixel and the second pixel.

[0025] In another embodiment of the present invention, the resolution of the pixel image is greater than or equal to the resolution of the display, wherein identifying a first image pixel corresponding to a first pixel and a second image pixel corresponding to a second pixel from the pixel image includes the following steps:

[0026] Identify the first image pixel whose brightness exceeds a first threshold in the pixel image as the first pixel; and

[0027] A second image pixel whose brightness does not exceed a second threshold is identified as the second pixel, wherein the first threshold is greater than or equal to the second threshold.

[0028] In another embodiment of the present invention, the resolution of the pixel image is smaller than the resolution of the display, and the resolution ratio is 1:R, wherein identifying the first image pixel corresponding to the first pixel and the second image pixel corresponding to the second pixel from the pixel image includes the following steps:

[0029] Divide every S adjacent pixels of the display into one large pixel, where S is the integer part of R rounded up; and

[0030] From the plurality of large pixels, a first image pixel whose brightness exceeds a first threshold is determined as the first pixel, and a second image pixel whose brightness does not exceed a second threshold is determined as the second pixel, wherein the first threshold is greater than or equal to the second threshold.

[0031] In another embodiment of the present invention, determining the brightness of the first image pixel and the second image pixel includes the following steps:

[0032] When multiple first image pixels exist, the average brightness of the multiple first image pixels is taken as the brightness of the first pixel; and

[0033] When there are multiple second image pixels, the maximum brightness of the second image pixels is taken as the brightness of the second pixel.

[0034] In another embodiment of the invention, the display is a miniature light-emitting diode display.

[0035] In a second aspect of the invention, the aforementioned task is accomplished by a method for determining optical crosstalk in display pixels, the method comprising the following steps:

[0036] A display is provided, the display having a plurality of pixels;

[0037] The display is divided into multiple sub-areas;

[0038] Light up one or more first pixels in each sub-region, where the N second pixels adjacent to each first pixel are not lit, where N is a positive integer;

[0039] Determine the brightness Vx of each first pixel and the brightness of the N second pixels associated with it;

[0040] Determine the maximum brightness Vmax among the brightness of the N second pixels;

[0041] The crosstalk factor Fc of each first pixel is determined by the following formula: Fc = Vmax / Vx; and the crosstalk factor of the display is determined based on the plurality of crosstalk factors.

[0042] In one embodiment of the present invention, determining the crosstalk factor of the display based on the plurality of crosstalk factors includes:

[0043] The average value of the multiple crosstalk factors is taken as the crosstalk factor of the display; or

[0044] The maximum value of the plurality of crosstalk factors is taken as the crosstalk factor of the display; or

[0045] The sum of the multiple crosstalk factors is taken as the crosstalk factor of the display.

[0046] In another embodiment of the invention, the sub-region includes:

[0047] Triangular pixel sub-regions, rectangular pixel sub-regions, rhomboid pixel sub-regions, polygonal pixel sub-regions, and irregularly shaped pixel sub-regions.

[0048] In another embodiment of the invention, the N second pixels of adjacent first pixels do not overlap with each other.

[0049] In a third aspect of the invention, the aforementioned task is solved by a pixel optical crosstalk testing system, the system comprising:

[0050] A camera configured to capture pixel images of a display having multiple pixels and divided into multiple sub-regions; and

[0051] The controller is configured to perform the following actions:

[0052] Send a control signal to the display to light up one or more first pixels in each sub-area, wherein N second pixels adjacent to each first pixel are not lit up, where N is a positive integer;

[0053] Identify a first image pixel corresponding to a first pixel and a second image pixel corresponding to a second pixel from the pixel image;

[0054] The brightness of the first image pixel and the second image pixel are determined as the brightness of the first pixel Vx and the N second pixels;

[0055] Determine the maximum brightness Vmax among the brightness of the N second pixels;

[0056] The crosstalk factor Fc of each first pixel is determined by the following formula: Fc = Vmax / Vx; and the crosstalk factor of the display is determined based on the plurality of crosstalk factors.

[0057] In one embodiment of the present invention, the resolution of the pixel image captured by the camera is greater than or equal to the resolution of the display, wherein identifying a first image pixel corresponding to a first pixel and a second image pixel corresponding to a second pixel from the pixel image includes the following steps:

[0058] Identify the first image pixel whose brightness exceeds a first threshold in the pixel image as the first pixel; and

[0059] A second image pixel whose brightness does not exceed a second threshold is identified as the second pixel, wherein the first threshold is greater than or equal to the second threshold.

[0060] In another embodiment of the present invention, the resolution of the pixel image is smaller than the resolution of the display, and the resolution ratio is 1:R, wherein identifying the first image pixel corresponding to the first pixel and the second image pixel corresponding to the second pixel from the pixel image includes the following steps:

[0061] Divide every S adjacent pixels of the display into one large pixel, where S is the integer part of R rounded up; and

[0062] From the plurality of large pixels, a first image pixel whose brightness exceeds a first threshold is determined as the first pixel, and a second image pixel whose brightness does not exceed a second threshold is determined as the second pixel, wherein the first threshold is greater than or equal to the second threshold.

[0063] In another embodiment of the present invention, determining the brightness of the first image pixel and the second image pixel includes the following steps:

[0064] When multiple first image pixels exist, the average brightness of the multiple first image pixels is taken as the brightness of the first pixel; and

[0065] When there are multiple second image pixels, the maximum brightness of the second image pixels is taken as the brightness of the second pixel.

[0066] The present invention has at least the following beneficial effects:

[0067] (1) The present invention calculates the ratio between the maximum brightness of the adjacent unlit pixels of the lit pixel and the brightness of the lit pixel. This simple calculation method can objectively reflect the crosstalk level of each pixel. The ratio is, for example, 0 to 1 (0 is no crosstalk, 1 is maximum crosstalk, and greater than 1 is an error value).

[0068] (2) In this invention, multiple pixels can be lit up at the same time and the crosstalk factor of these pixels can be calculated. The brightness of multiple pixels and their surrounding pixels can be captured by a camera at one time, and the crosstalk of multiple pixels can be determined at the same time. Therefore, this method is simple to operate and has a small amount of calculation.

[0069] (3) In this invention, since the crosstalk factor is the quotient of the brightness of the lit pixel and the maximum brightness of its adjacent pixels, the influence of the measurement error of the brightness device on the measurement result can be reduced. The reason is as follows: when measuring devices such as luminance meters and cameras measure the brightness of multiple pixels simultaneously, the brightness error offset ratios of the multiple pixels are consistent. This means that when the final result is divided, the error is eliminated. For example, when a camera captures the brightness of multiple pixels, even if the brightness of these pixels in the captured image of the same pixel has an error, their error offset ratios are consistent. For example, if their actual brightness is all offset downwards by 5%, and their brightness all becomes 95%, then the brightness of the first pixel becomes 95%*Vx, and the maximum brightness of the second pixel becomes 95%*Vmax. Therefore, the measurement result of the crosstalk factor Fc is (95%*Vmax) / (95%*Vx) = Vmax / Vx. It can be seen that the measurement result is still accurate and is not affected by the camera's brightness shooting error. Thus, the crosstalk factor calculation method of this invention can effectively reduce the influence of the measurement error of the brightness device on the measurement result, thereby providing a more accurate measurement result. Attached Figure Description

[0070] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0071] Figure 1A and 1B A first embodiment of a method for determining optical crosstalk in display pixels according to the present invention is shown;

[0072] Figure 2A and 2B A second embodiment of the method for determining optical crosstalk of display pixels according to the present invention is shown;

[0073] Figure 3 A third embodiment of the method for determining optical crosstalk of display pixels according to the present invention is shown;

[0074] Figure 4 A schematic diagram of a pixel optical crosstalk testing system according to the present invention is shown; and

[0075] Figure 5 A schematic diagram of a micro-light-emitting diode chip for a micro-light-emitting diode display under test according to the present invention is shown. Detailed Implementation

[0076] In the following description, the invention is described with reference to various embodiments. However, those skilled in the art will recognize that the embodiments may be practiced without one or more specific details or with other alternatives and / or additional methods, materials, or components. In other instances, well-known structures, materials, or operations are not shown or described in detail so as not to obscure the inventive points of the invention. Similarly, for illustrative purposes, specific quantities, materials, and configurations are set forth to provide a comprehensive understanding of embodiments of the invention. However, the invention is not limited to these specific details.

[0077] It should be noted that the components in the various figures may be shown exaggeratedly for illustrative purposes and are not necessarily to scale. In each figure, the same reference numerals are used for components that are identical or have the same function.

[0078] In this invention, unless otherwise specified, "arranged on," "arranged above," and "arranged on" do not exclude the possibility of an intermediate element between them. Furthermore, "arranged on or above" merely indicates the relative positional relationship between two components, and in certain cases, such as when the product orientation is reversed, it can also be converted to "arranged below or under," and vice versa.

[0079] In this invention, the various embodiments are merely intended to illustrate the solutions of the invention and should not be construed as limiting.

[0080] In this invention, unless otherwise specified, the quantifiers “a” and “one” do not exclude scenarios involving multiple elements.

[0081] In this invention, the term "connection" can refer to a direct connection between two things or an indirect connection between two things through an intermediate element.

[0082] In this application, the term "configuration" refers to setting the shape, structure, material and / or function of a target object to achieve a desired technical effect. "Configuration" includes a variety of alternative technical means to achieve the technical effect, which become apparent from the teachings of this application.

[0083] In this specification, references to "an embodiment" or "this embodiment" mean that a particular feature, structure, or characteristic described in connection with that embodiment is included in at least one embodiment of the invention. The phrase "in one embodiment" appearing throughout this specification does not necessarily refer to the same embodiment in all instances.

[0084] It should be noted that the embodiments of the present invention describe the process steps in a specific order; however, this is only for illustrating the specific embodiment and not for limiting the order of the steps. On the contrary, in different embodiments of the present invention, the order of the steps can be adjusted according to the process.

[0085] Figure 1A and 1B A first embodiment of a method for determining optical crosstalk in display pixels according to the present invention is shown, wherein FIG1 illustrates the method for determining optical crosstalk when a single pixel of the display is lit. Figure 1B The image shown is a pixel image of the display captured by a camera, and in this embodiment, the second pixel comprises a single pixel layer directly adjacent to the first pixel.

[0086] As shown in Figure 1, the display 100 has a plurality of pixels, each represented by a grid in Figure 1. Each pixel is, for example, a miniature light-emitting diode (LED). In this invention, the display 100 encompasses various forms and types of displays, such as monochrome displays, color displays, light-emitting panels, printer printheads, miniature LED displays, etc. In this embodiment, to test the light crosstalk factor of the display 100 when a single pixel 101 is lit, pixel 101 can be lit and the maximum brightness of pixel 101 and its N neighboring pixels can be measured. Here, N = 8, but in other embodiments, other numbers are conceivable. The number N of neighboring pixels can be determined based on several factors, such as the distance between the light emitted by a single neighboring pixel and the farthest pixel that the light can reach, or the number N can be set large enough to cover distances that the light cannot reach. However, generally, since the probability of a pixel reaching maximum brightness decreases significantly with increasing distance from the lit pixel, the number N can be set to 1 to 10 layers of pixels surrounding the lit pixel. In this way, the crosstalk test takes into account as many crosstalked pixels as possible. The following describes the process of determining the optical crosstalk of display pixels:

[0087] • In step S1, a display 100 is provided. The display 100 is, for example, a miniature light-emitting diode display. The display 100 has a plurality of pixels, for example, a plurality of miniature light-emitting diodes. In this embodiment, the display 100 has 10x16 pixels, the positions of which can be represented in matrix form (x, y), where x is the row position of the pixel and y is the column position of the pixel.

[0088] In step S2, the first pixel 101 of the plurality of pixels is illuminated, while the N second pixels 102 adjacent to the first pixel are not illuminated, where N is a positive integer. Here, N = 8, meaning that the 8 pixels 102 directly adjacent to the first pixel 101 are not illuminated. The number of N is merely exemplary, and other numbers are conceivable. Here, one or more pixels are illuminated by inputting a control signal to the driving circuit of the display 100.

[0089] • In step S3, the brightness Vx of the first pixel 101 and the brightness of the N second pixels 102 are determined. For example, the brightness of the pixels can be determined in the following manner.

[0090] First, a pixel image of the display is captured by a camera. Referring to Figure 2, pixel image 200 is a display image of the display 100 captured by the camera, wherein the first pixel 101 is lit and the second pixel 102 is not lit. As shown in Figure 2, pixel image 200 includes 5*5 image pixels, wherein image pixel 201 corresponds to pixel 101 of the display, and image pixel 202 corresponds to pixel 102 of the display.

[0091] Then, a first image pixel 201 corresponding to the first pixel 101 and a second image pixel 202 corresponding to the second pixel 102 are identified from the pixel image, and the brightness of the first image pixel and the second image pixel are determined as the brightness of the first pixel and the second pixel, respectively.

[0092] The resolution of pixel image 100 may be greater than or equal to the resolution of display 100. "The resolution of pixel image is greater than or equal to the resolution of display" means that the pixel image can distinguish each pixel of the display. However, the number of pixels in the pixel image is not necessarily greater than the number of pixels on the display, but may be less than or equal to the number of pixels on the display. For example, the unit of resolution is dpi (dots per inch). When the resolution of pixel image 100 may be greater than or equal to the resolution of display 100, identifying the first image pixel 201 and the second image pixel 202 from the pixel image includes the following steps: First, identify a first image pixel in the pixel image whose brightness exceeds a first threshold as the first pixel. This identification process can be performed, for example, by reading the binary brightness value of the pixel image. Then, identify a second image pixel in the pixel image whose brightness does not exceed a second threshold as the second pixel, where the first threshold is greater than or equal to the second threshold. Finally, read the binary brightness value of the image based on the position information of the first and second image pixels. The read brightness value can be used as the brightness Vx of the first pixel 101 and the brightness of the N second pixels 102.

[0093] When the resolution of pixel image 100 is less than the resolution of the display, the individual pixels of display 100 cannot be distinguished in pixel image 200. Therefore, the pixels of the display need to be divided according to the pixel ratio of pixel image 200 to display 100 (R rounded up). For example, when the resolution of pixel image 200 to display 100 is 1:R, every S pixels of display 100 (S is the integer part of R) needs to be divided into one large pixel. This large pixel is then illuminated, while the surrounding N large pixels are not illuminated. Next, a first image pixel whose brightness exceeds a first threshold is determined from these large pixels, and a second image pixel whose brightness does not exceed a second threshold is determined, where the first threshold is greater than or equal to the second threshold. Finally, the binary brightness value of the image is read based on the position information of the first and second image pixels. The read brightness value can be used as the brightness Vx of the first pixel 101 and the brightness of the N second pixels 102.

[0094] The first threshold is, for example, the brightness value of a normally lit pixel, or a range of fluctuation of that brightness value, such as fluctuation of 1%, 5%, or 10%.

[0095] The first threshold is, for example, a certain percentage of the brightness value of normally lit pixels, such as 20%, 30%, 30%, 80%, or 85%.

[0096] In step S4, the maximum brightness Vmax among the brightness values ​​of the N second pixels is determined. The brightness value of a pixel can be obtained from the image information of the pixel image, for example, by obtaining the binary brightness value of the corresponding pixel. As shown in Figure 2, the brightness of the first image pixel 201 is Vx, and two pixels in the second image pixel 202 have brightness values, namely image pixels (2,4) and (4,4), and their brightness values ​​are V1 and V2, respectively. Here, V1 > V2, therefore the maximum brightness value of the second pixel Vmax = V1.

[0097] In step S5, the crosstalk factor Fc is determined using the following formula: Fc = Vmax / Vx. That is, the crosstalk factor Fc is the ratio of the maximum brightness value Vmax of the second pixel to the brightness value of the first pixel. This reduces the impact of measurement errors from the brightness device on the measurement results. The reason is as follows: when measuring devices such as luminance meters and cameras simultaneously measure the brightness of multiple pixels, the brightness error offset ratios of the multiple pixels are consistent. This means that when the final result is divided, the error is eliminated. For example, when a camera captures the brightness of multiple pixels, even if the brightness of these pixels in the captured image of the same pixel has errors, their error offset ratios are consistent. For instance, if their brightness is all offset downwards by 5% from the actual brightness, becoming 95%, then the brightness of the first pixel becomes 95%*Vx, and the maximum brightness of the second pixel becomes 95%*Vmax. Therefore, the measurement result of the crosstalk factor Fc is (95%*Vmax) / (95%*Vx) = Vmax / Vx. It is evident that the measurement result remains accurate and is not affected by camera brightness capture errors. Therefore, the crosstalk factor calculation method of the present invention can effectively reduce the influence of the measurement error of the brightness device on the measurement results, thereby providing more accurate measurement results.

[0098] Figure 2 illustrates a second embodiment of the method for determining optical crosstalk of display pixels according to the present invention, wherein Figure 2 shows the method for determining optical crosstalk when a single pixel of the display is lit. Figure 2B The image shows a pixel image of the display taken by a camera, and in this embodiment, the second pixel includes two pixel layers directly adjacent to the first pixel.

[0099] Figure 2A and 2B The second embodiment and Figure 1A and 1B The first embodiment is basically the same, the main difference being that in Figure 2, the second pixel adjacent to the first pixel 301 includes two pixel layers 303 and 304, which include:

[0100] • The first pixel layer 303 includes eight second pixels 302A that are directly adjacent to the first pixel 301.

[0101] • The second pixel layer 304 includes 16 second pixels 302B that are directly adjacent to the first pixel layer 303.

[0102] It should be noted that the number of pixel layers adjacent to the first pixel 301 is merely exemplary. In other embodiments, more pixel layers may be included, such as the third pixel layer (which includes 24 second pixels), the fourth pixel layer (which includes 32 second pixels)..., the m-th pixel layer (which includes 8m second pixels, where m is a positive integer).

[0103] like Figure 2B As shown, the pixel image 400 of the display 300 captured by the camera includes 5x5 image pixels, wherein the first image pixel 401 corresponds to the first pixel 301, and the second image pixel 402 corresponds to the second pixels 302A and 302B.

[0104] Here, the brightness of the first image pixel 401 can be used as the brightness value Vx of the first pixel 301, and the second image pixel 402 has the following image pixels with non-zero brightness values:

[0105] The second image pixel (1,5) has a brightness value of V3;

[0106] The second image pixel (1,2) has a brightness value of V4;

[0107] The second image pixel (2,4) has a brightness value of V5;

[0108] The second image pixel (4,4) has a brightness value of V6.

[0109] Among them, V5>V6>V4>V3, with V5 being the largest.

[0110] Therefore, the brightness value V5 of the second image pixel (2,4) can be used as the maximum brightness value Vmax of the second pixels 302A and 302B.

[0111] Then, the crosstalk factor Fc can be determined according to the formula Fc = Vmax / Vx.

[0112] Figure 3 A third embodiment of the method for determining optical crosstalk of display pixels according to the present invention is shown.

[0113] Figure 3 The third embodiment and Figure 1A and 1B The first embodiment is basically the same, the main difference being that... Figure 3 In this process, multiple first pixels are illuminated, and multiple crosstalk factors are determined for each.

[0114] like Figure 5 As shown, the display 500 is divided into 15 sub-regions 503 and an edge region 504, where each sub-region includes one first pixel 501 and eight second pixels 502. Here, the edge region 504 is not included in the test. In other embodiments, pixels in the edge region 504 may also be assigned to adjacent sub-regions 503.

[0115] Here, following a similar approach to the first and second embodiments, 15 crosstalk factors Fc1 to Fc15 can be measured and calculated for each sub-region 503.

[0116] Based on the 15 crosstalk factors Fc1 to Fc15, the crosstalk factor of the display 500 can be calculated, for example, by one of the following methods:

[0117] (1) Take the average value of the multiple crosstalk factors Fc1 to Fc15 as the crosstalk factor of the display 500.

[0118] (2) Take the maximum value of the plurality of crosstalk factors Fc1 to Fc15 as the crosstalk factor of the display 500.

[0119] (3) Take the sum of the multiple crosstalk factors Fc1 to Fc15 as the crosstalk factor of the display 500.

[0120] Other calculation methods are also conceivable, such as determining the weighted sum of crosstalk factors Fc1 to Fc15, where different sub-regions 503 have different weighting coefficients. For example, sub-regions 503 closer to the center of the screen have larger weighting coefficients, while the weighting coefficients are smaller the further away from the center of the screen.

[0121] Figure 4 A schematic diagram of a pixel optical crosstalk testing system 700 according to the present invention is shown.

[0122] like Figure 4 As shown, the pixel optical crosstalk testing system 700 according to the present invention includes a camera 701 and a controller 703. Furthermore, the pixel optical crosstalk testing system 700 may optionally include a router 704 and a network 705, such as the Internet and an intranet. The components of the pixel optical crosstalk testing system 700 are described below.

[0123] A camera 701 is configured to capture pixel images of a display 702, wherein the display 702 has multiple pixels and is divided into multiple sub-regions. The display 702 encompasses various forms and types of displays, such as monochrome displays, color displays, light-emitting panels, printer printheads, miniature light-emitting diode displays, etc. The camera 701 can be a digital camera, a webcam, a brightness sensor, a luminance meter, etc.

[0124] The controller 703 can be of various forms, such as a microprocessor CPU, a microcontroller MCU, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a personal computer, etc. Here, the controller 703 is shown as a computer. The controller 703 is configured, for example, by software or hardware programming, to determine one or more crosstalk factors based on the captured pixel image. For example, the controller 703 is configured to perform the following actions:

[0125] Control signals are sent to the display 702 via optional network 705 and router 704 to illuminate one or more first pixels in each sub-area, wherein N second pixels adjacent to each first pixel are not illuminated, where N is a positive integer.

[0126] Identify a first image pixel corresponding to a first pixel and a second image pixel corresponding to a second pixel from the pixel image;

[0127] The brightness of the first image pixel and the second image pixel are determined as the brightness of the first pixel Vx and the N second pixels;

[0128] Determine the maximum brightness Vmax among the brightness of the N second pixels;

[0129] The crosstalk factor Fc of each first pixel is determined by the following formula: Fc = Vmax / Vx; and the crosstalk factor of the display is determined based on the plurality of crosstalk factors.

[0130] • An optional router 704 is configured to connect camera 701 to network 705. Alternatively, in another application scenario, router 704 is configured to enable communication between camera 701 and controller 703, for example, both camera 701 and controller 703 are connected to router 704, allowing them to communicate directly via wired or wireless means. Router 704 can be, for example, a wired router or a Wi-Fi router.

[0131] An optional network 705 is configured to enable communication between the controller 703 and the router 704, thereby enabling communication between the controller 703 and the camera 701. Network 705 can be, for example, the Internet or an intranet. Display 702 can optionally also be connected to network 705 or router 704, allowing the controller 703 to send control signals to display 702 via network 705 or router 704 to illuminate the corresponding first pixel, thus enabling remote testing. Here, display 702 is connected to router 704. Alternatively, display 702 can also be connected to a controller located in the field for direct control.

[0132] Figure 5 A schematic diagram of a micro-light-emitting diode chip for a micro-light-emitting diode display under test according to the present invention is shown.

[0133] like Figure 5 As shown, the micro-light-emitting diode chip of the micro-light-emitting diode display under test of the present invention includes the following components:

[0134] The substrate 601 may be made of materials such as ceramic, quartz glass, silicate glass, soda-lime glass, fluoride glass, silicon oxide, or silicon nitride. For example, using a ceramic substrate to support the micro-LED chip can improve the substrate's mechanical strength, thus providing better protection for the micro-LED chip. Furthermore, compared to silicon substrates, ceramics offer better insulation, thereby improving the insulation of the micro-LED chip and preventing leakage current or interference from external currents.

[0135] A driving circuit 602 (i.e., driving backplane 101B) is formed on the substrate 601. The driving circuit 602 may be, for example, a thin-film transistor (TFT) driving circuit, and may include a 2T1C driving circuit, a 3T1C driving circuit, and a 5T2C driving circuit. The driving circuit 602 is configured to drive micro-light-emitting diodes (LEDs), for example, controlling the switching on, off, and brightness of the micro-LEDs. The driving circuit 602 may include, for example, transistors, capacitors, a conductive line layer, an insulating layer, and a metal layer. The conductive line layer is formed on the substrate and configured to supply power to the micro-LED array. An insulating layer is formed on the conductive line layer, wherein through-holes are provided in the insulating layer, and through-hole contacts (e.g., IC copper pillars) are provided in the through-holes for electrically connecting the conductive line layer to the micro-LED array. The metal layer is used for bonding and electrically contacting the micro-LEDs. The conductive circuit layer, metal layer, and insulating layer can be formed on the substrate 601 by deposition, such as physical vapor deposition (PVD) and chemical vapor deposition (CVD). Depending on the specific application, the metal layer and insulating layer can be patterned by photolithography and vias can be formed on them. Furthermore, transistors and capacitors in the conductive circuit layer can be formed by deposition and etching.

[0136] A micro-LED array 603 includes an epitaxial layer 608. The micro-LED array 603 is formed on a driving circuit 603 or a substrate 601. The specific structure of the epitaxial layer is described below. The micro-LED array 603 is bonded to the driving circuit 602 or the substrate 601 by bonding, including full-surface bonding and hybrid bonding. In some embodiments, the micro-LED array may include blue micro-LEDs. In some embodiments, the spacing of the micro-LED array, i.e., the minimum center-to-center distance between the micro-LEDs, may be between about 2 micrometers and about 50 micrometers. In some embodiments, the number of pixels on the micro-LED chip 100 may be between several thousand and several million.

[0137] Each miniature light-emitting diode includes the following components:

[0138] An epitaxial layer 608 is configured to emit light. The epitaxial layer includes a first epitaxial layer, a second epitaxial layer, and a light-emitting layer disposed between the first and second epitaxial layers. The epitaxial layer 108 comprises a first epitaxial layer, a light-emitting layer, and a second epitaxial layer deposited sequentially, wherein the light-emitting layer includes a multiple quantum well layer and an electron blocking layer. In one embodiment of the invention, the first epitaxial layer is an N-type GaN layer or an N-type AlGaN layer, and the second epitaxial layer is a P-type GaN layer or a P-type AlGaN layer. That is, the material of the second epitaxial layer can be a material layer of a second conductivity type comprising at least two or more elements of Ga, N, As, Al, In, and P, and the first epitaxial layer can be a material layer of a first conductivity type comprising at least two or more elements of Ga, N, As, Al, In, and P. The multiple quantum well layer is an InGaN / GaN multiple quantum well layer, an InGaN / AlGaN multiple quantum well layer, or an InGaAs / AlGaAs multiple quantum well layer. The electron blocking device is disposed on a first side of the light-emitting layer, where the first side refers to the side along which electrons migrate out of the light-emitting layer. In another embodiment of the present invention, the first epitaxial layer may also be a P-type GaN layer or a P-type AlGaN layer, and the second epitaxial layer may be an N-type GaN layer or an N-type AlGaN layer.

[0139] The cathode 611 is electrically connected to the first epitaxial layer of the epitaxial layer 603 via a transparent conductive layer 609 and a cathode contact 114 passing through the passivation layer 615. The cathode 611 can be a ring-shaped reflective electrode, disposed around the epitaxial layer 608, and can be formed, for example, by magnetron sputtering or vapor deposition. Its material can be, for example, Al or Al alloy metal for the sidewall reflective surface, and the electrode stack metal can be Ni, Al, Ti, Pt, Au, or other metal materials. The passivation layer 115 is disposed between the transparent conductive layer 609 and the epitaxial layer 608. Its function is not only to reduce current leakage at the sidewalls, but also to passivate sidewall defects and prevent water, oxygen, etc., from damaging the light-emitting mesa during operation. The passivation layer 114 can be formed by depositing SiO2 material using a CVD process or by depositing Al2O3 material using an ALD process. The cathode 111 can be, for example, a common cathode structure, i.e., an array of micro-light-emitting diodes connected to a common cathode.

[0140] • An anode 613 is disposed at the bottom of the epitaxial layer 608 to provide power. The anode 613 of each array of micro-LEDs can be selectively connected to the signal contact 612. The common cathode and selective anode connection can form a passive matrix control method to control the on / off state and brightness adjustment of each micro-LED. Additional layers, such as a passivation layer 615, a transparent conductive layer 609, a cathode 611, etc., are also provided on the epitaxial layer 608 and the anode 613. In addition, signal contacts 612 are formed on the side to bring out the anode 613 of the corresponding micro-LED.

[0141] Multiple miniature light-emitting diodes (LEDs) constitute a miniature LED array, and multiple miniature LED arrays in turn constitute a miniature LED chip. Each miniature LED chip is no larger than 1 cm in size, and the miniature LEDs are preferably no larger than 2050 micrometers. The miniature LED structure is formed in an array within the miniature LED chip, achieving printing resolutions such as 1200 DPI, 600 DPI, and resolutions such as 720*480, 640*480, 1920*1080, 1280*720, 2K, or 4K. The diameter of the miniature LED structure is in the nanometer / micrometer range, for example, from 20 nm to 100 to 50 nm.

[0142] While some embodiments of the invention have been described in this application, those skilled in the art will understand that these embodiments are merely illustrative. Numerous variations, alternatives, and improvements will arise in those skilled in the art under the teachings of this invention without departing from its scope. The appended claims are intended to define the scope of the invention and thereby cover the methods and structures within the scope of the claims themselves and their equivalents.

Claims

1. A method for determining optical crosstalk in display pixels, comprising the following steps: A display is provided, the display having a plurality of pixels; Light up the first pixel among the plurality of pixels, wherein the N second pixels adjacent to the first pixel are not lit, where N is a positive integer; Determine the brightness Vx of the first pixel and the brightness of the N second pixels; Determine the maximum brightness Vmax among the brightness of the N second pixels; as well as The crosstalk factor Fc is determined using the following formula: Fc = Vmax / Vx.

2. The method according to claim 1, wherein the N second pixels comprise m pixel layers, where m is a positive integer, and the m pixel layers comprise: The first pixel layer includes 8 pixels directly adjacent to the first pixel; The second pixel layer includes 16 pixels that are directly adjacent to the first pixel layer; … The m-th pixel layer comprises 8m pixels directly adjacent to the (m-1)-th pixel layer.

3. The method of claim 1, wherein the N second pixels comprise a pixel block, wherein the first pixel is one of the internal pixels of the pixel block, and the pixel block comprises one of the following: Triangular pixel blocks, rectangular pixel blocks, diamond pixel blocks, polygonal pixel blocks, and irregularly shaped pixel blocks.

4. The method of claim 3, wherein the first pixel is the center pixel of the pixel block or the pixel closest to the center pixel.

5. The method according to claim 1, wherein determining the brightness Vx of the first pixel and the brightness of the N second pixels comprises the following steps: Capture pixel images of the display using a camera; Identify, from the pixel image, a first image pixel corresponding to a first pixel and a second image pixel corresponding to a second pixel; and The brightness of the first image pixel and the second image pixel are determined as the brightness of the first pixel and the second pixel.

6. The method of claim 1, wherein the resolution of the pixel image is greater than or equal to the resolution of the display, wherein identifying the first image pixel corresponding to the first pixel and the second image pixel corresponding to the second pixel from the pixel image comprises the following steps: Identify the first image pixel whose brightness exceeds a first threshold in the pixel image as the first pixel; and A second image pixel whose brightness does not exceed a second threshold is identified as the second pixel, wherein the first threshold is greater than or equal to the second threshold.

7. The method according to claim 1, wherein the resolution of the pixel image is less than the resolution of the display, and the resolution ratio is 1:R, wherein identifying the first image pixel corresponding to the first pixel and the second image pixel corresponding to the second pixel from the pixel image comprises the following steps: Divide every S adjacent pixels of the display into one large pixel, where S is the integer part of R rounded up; and From the plurality of large pixels, a first image pixel whose brightness exceeds a first threshold is determined as the first pixel, and a second image pixel whose brightness does not exceed a second threshold is determined as the second pixel, wherein the first threshold is greater than or equal to the second threshold.

8. The method according to any one of claims 6 to 7, wherein determining the brightness of the first image pixel and the second image pixel comprises the following steps: When multiple first image pixels exist, the average brightness of the multiple first image pixels is taken as the brightness of the first pixel; and When there are multiple second image pixels, the maximum brightness of the second image pixels is taken as the brightness of the second pixel.

9. The method according to any one of claims 1 to 8, wherein the display is a micro light-emitting diode display.

10. A method for determining optical crosstalk in display pixels, comprising the following steps: A display is provided, the display having a plurality of pixels; The display is divided into multiple sub-areas; Light up one or more first pixels in each sub-region, where the N second pixels adjacent to each first pixel are not lit, where N is a positive integer; Determine the brightness Vx of each first pixel and the brightness of the N associated second pixels; Determine the maximum brightness Vmax among the brightness of the N second pixels; The crosstalk factor Fc for each first pixel is determined using the following formula: Fc = Vmax / Vx; and The crosstalk factor of the display is determined based on the plurality of crosstalk factors.

11. The method of claim 10, wherein determining the crosstalk factor of the display based on the plurality of crosstalk factors comprises: The average value of the multiple crosstalk factors is taken as the crosstalk factor of the display. or The maximum value of the plurality of crosstalk factors is taken as the crosstalk factor of the display. or The sum of the multiple crosstalk factors is taken as the crosstalk factor of the display.

12. The method of claim 10, wherein the sub-region comprises: Triangular pixel sub-regions, rectangular pixel sub-regions, rhomboid pixel sub-regions, polygonal pixel sub-regions, and irregularly shaped pixel sub-regions.

13. The method of claim 10, wherein N second pixels adjacent to the first pixel do not overlap with each other.

14. A pixel optical crosstalk testing system, comprising: A camera configured to capture pixel images of a display having multiple pixels and divided into multiple sub-regions; as well as The controller is configured to perform the following actions: Send a control signal to the display to light up one or more first pixels in each sub-area, wherein N second pixels adjacent to each first pixel are not lit up, where N is a positive integer; Identify a first image pixel corresponding to a first pixel and a second image pixel corresponding to a second pixel from the pixel image; The brightness of the first image pixel and the second image pixel are determined as the brightness of the first pixel Vx and the N second pixels; Determine the maximum brightness Vmax among the brightness of the N second pixels; The crosstalk factor Fc for each first pixel is determined using the following formula: Fc = Vmax / Vx; and The crosstalk factor of the display is determined based on the plurality of crosstalk factors.

15. The pixel optical crosstalk testing system according to claim 14, wherein the resolution of the pixel image captured by the camera is greater than or equal to the resolution of the display, wherein identifying the first image pixel corresponding to the first pixel and the second image pixel corresponding to the second pixel from the pixel image includes the following steps: Identify the first image pixel whose brightness exceeds a first threshold in the pixel image as the first pixel; and A second image pixel whose brightness does not exceed a second threshold is identified as the second pixel, wherein the first threshold is greater than or equal to the second threshold.

16. The pixel optical crosstalk testing system according to claim 14, wherein the resolution of the pixel image is less than the resolution of the display, and the resolution ratio is 1:R, wherein identifying the first image pixel corresponding to the first pixel and the second image pixel corresponding to the second pixel from the pixel image includes the following steps: Divide every S adjacent pixels of the display into one large pixel, where S is the integer part of R rounded up; and From the plurality of large pixels, a first image pixel whose brightness exceeds a first threshold is determined as the first pixel, and a second image pixel whose brightness does not exceed a second threshold is determined as the second pixel, wherein the first threshold is greater than or equal to the second threshold.

17. The pixel optical crosstalk testing system according to claim 14, wherein determining the brightness of the first image pixel and the second image pixel comprises the following steps: When multiple first image pixels exist, the average brightness of the multiple first image pixels is taken as the brightness of the first pixel; and When there are multiple second image pixels, the maximum brightness of the second image pixels is taken as the brightness of the second pixel.

Images