Micro-LED thermal simulation method and device
By using a three-dimensional power density dataset for thermal simulation in a Micro-LED array, the problem of inaccurate thermal risk identification in existing technologies is solved, and an efficient and accurate thermal simulation process is achieved.
Patent Information
- Application Number
- CN202511039333.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-28
- Publication Date
- 2025-11-14
AI Technical Summary
Existing micro-LED thermal simulation methods cannot accurately identify thermal risks, resulting in overly lenient simulation results. Furthermore, frequent division of regions is required when power distribution changes, making the operation cumbersome.
Simulations were performed using a 3D power density dataset of all pixels in the Micro-LED array. By establishing a coordinate system, obtaining feature coordinates, normalizing the luminous lumen distribution, and calculating power distribution parameters, and combining VBA automated processing, the data was imported into Micro-LED thermal simulation software for thermal simulation.
It significantly improved the accuracy of thermal simulation, shortened the simulation time by 98%, reduced human error, and improved accuracy.
Smart Images
Figure CN120951544A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of simulation technology, and in particular to a method and apparatus for thermal simulation of Micro-LEDs. Background Technology
[0002] The design of LED products is a complex multidisciplinary problem. In particular, heat dissipation design is crucial to the performance and lifespan of the device. Using tools for thermal simulation can better provide products that meet reliability, size and performance goals. Therefore, the accuracy of thermal simulation is particularly critical.
[0003] Micro LED (micro-light emitting diode) is a new type of display technology that has attracted much attention due to its high brightness, high color saturation, low power consumption and long lifespan. However, due to the large number of Micro LEDs and the small size of a single pixel, it is difficult to perform thermal simulation using the actual power distribution, which increases the difficulty of identifying thermal risks.
[0004] Currently, there are two main types of thermal simulation methods:
[0005] (1) Treat the Micro-LED as a whole and apply the total power as a power boundary condition.
[0006] This method maintains a consistent total power, but it can result in local power densities that differ from reality, leading to overly lenient thermal simulation results and an inability to identify thermal risks.
[0007] (2) Divide the pixels with similar Micro-LED power into a region and apply the total power of the region as the power boundary condition. This process divides the region into dozens of regions.
[0008] While this method maintains a consistent total power across all regions, local power densities may still differ from actual values. This can lead to overly lenient thermal simulation results and an inability to identify risks. Furthermore, re-dividing the regions is cumbersome when power distribution changes. Summary of the Invention
[0009] To overcome the above shortcomings, this invention provides a Micro-LED thermal simulation method and apparatus that can simultaneously simulate the three-dimensional power density dataset of all pixels in a Micro-LED array, thereby greatly improving the accuracy of Micro-LED thermal simulation and better identifying thermal risks.
[0010] The technical solution provided by this invention is as follows:
[0011] On one hand, this invention provides a Micro-LED thermal simulation method applied to a Micro-LED array. Each pixel in the Micro-LED array includes a chip layer, a phosphor layer disposed on the light-emitting side surface of the chip layer, and a driving layer disposed on the electrode side of the chip layer. The Micro-LEDs are arranged in an array. The Micro-LED thermal simulation method includes:
[0012] A coordinate system is established based on the Micro-LED array, and the feature coordinates of one pixel are obtained. The feature coordinates are: the coordinates of the vertex of any one of the chip layer, phosphor layer and driving layer; and the midpoint coordinates of the phosphor layer, chip layer and driving layer are the midpoint coordinates of the edge of each layer perpendicular to the phosphor layer along any vertex.
[0013] The light lumen distribution of the Micro-LED array is normalized to a duty cycle distribution;
[0014] Based on the optical duty cycle distribution data, the power distribution parameters of different structural layers of each pixel in the Micro-LED array are obtained;
[0015] By combining the feature coordinates of the pixels, a three-dimensional power density dataset of each pixel in the Micro-LED array is obtained, and then imported into Micro-LED thermal simulation software to map to 3D data for thermal simulation.
[0016] On the other hand, the present invention provides a Micro-LED thermal simulation device applied to a Micro-LED array. Each pixel in the Micro-LED array includes a chip layer, a phosphor layer disposed on the light-emitting side surface of the chip layer, and a driving layer disposed on the electrode side of the chip layer. The Micro-LEDs are arranged in an array. The Micro-LED thermal simulation device includes:
[0017] The feature coordinate acquisition module is used to establish a coordinate system based on the Micro-LED array and acquire the feature coordinates of a pixel. The feature coordinates are: the coordinates of the vertex of any one of the chip layer, phosphor layer and driving layer; and the midpoint coordinates of the phosphor layer, chip layer and driving layer are the midpoint coordinates of the edge of each layer perpendicular to the phosphor layer along any vertex.
[0018] The optical duty cycle distribution data acquisition module is used to normalize the light lumen distribution of the Micro-LED array into a duty cycle distribution;
[0019] The power distribution parameter acquisition module is used to obtain the power distribution parameters of different structural layers of each pixel in the Micro-LED array based on the optical duty cycle distribution data.
[0020] The three-dimensional power density dataset acquisition module is used to combine the feature coordinates of the pixel points to obtain the three-dimensional power density dataset of each pixel point in the Micro-LED array, and import it into the Micro-LED thermal simulation software to map it to 3D data for thermal simulation.
[0021] The Micro-LED thermal simulation method and apparatus provided by this invention can bring at least the following beneficial effects:
[0022] 1) No need to divide 3D data. The simulation is performed using tens of thousands of coordinate-based 3D power density datasets (x, y, z, power density) with the same number of actual pixels, which greatly improves the thermal simulation accuracy of Micro-LED and better identifies thermal risks.
[0023] 2) By using VBA to automatically distribute the pivot table, the process time is reduced by more than 98% (from 2400s to 3s), which greatly improves efficiency, reduces errors caused by manual operation, and improves accuracy. Attached Figure Description
[0024] Figure 1 This is a schematic diagram of the Micro-LED thermal simulation method in this invention;
[0025] Figure 2 This is a schematic diagram of the coordinates of the fluorescent layer in this invention;
[0026] Figure 3 This is a schematic diagram showing the coordinates of the chip layer, phosphor layer, and driving layer in this invention;
[0027] Figure 4 This is a schematic diagram of the Micro-LED thermal simulation device in this invention.
[0028] Figure label:
[0029] 10 - Feature coordinate acquisition module; 20 - Optical duty cycle distribution data acquisition module; 30 - Power distribution parameter acquisition module; 40 - Three-dimensional power density dataset acquisition module. Detailed Implementation
[0030] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings and other implementation methods can be obtained based on these drawings without any creative effort.
[0031] The Micro-LED thermal simulation method provided by this invention is applied to Micro-LED arrays. Each pixel in the Micro-LED array includes a chip layer, a phosphor layer disposed on the light-emitting side surface of the chip layer, and a driving layer disposed on the electrode side of the chip layer. The Micro-LEDs are arranged in an array.
[0032] like Figure 1 As shown, the Micro-LED thermal simulation method includes:
[0033] S10 establishes a coordinate system based on the Micro-LED array and obtains the feature coordinates of one pixel. The feature coordinates are: the coordinates of the vertex of any one of the chip layer, phosphor layer and driving layer; the midpoint coordinates of the phosphor layer, chip layer and driving layer are the midpoint coordinates of the edge of each layer perpendicular to the phosphor layer along any vertex.
[0034] In this invention, thermal simulation is performed based on the three-layer structure of Micro-LED. Therefore, after establishing the coordinate system, the feature coordinates of the pixel points are also determined based on the three-layer structure.
[0035] In one example, such as Figure 2 and Figure 3 As shown, the feature coordinates of one pixel include the coordinates of each vertex on the side of the fluorescent layer furthest from the chip layer (corresponding to...). Figure 2 Points A, B, C, and D (AB is the longer side, CD is the shorter side) are considered. The coordinates of the midpoint of the fluorescent layer, determined by the thickness of each layer, are taken from any vertex perpendicular to the edge of the fluorescent layer. Figure 3 (point E in the middle) and the coordinates of the midpoint of the chip layer (corresponding to...) Figure 3 The coordinates of point F in the driving layer and the midpoint of the driving layer (corresponding to...) Figure 3 (G point in the middle).
[0036] In a Micro-LED array, the pixels are arranged in an array. Based on the feature coordinates of a certain pixel, the feature coordinates of other pixels can be determined based on the established coordinate system.
[0037] S20 normalizes the light lumen distribution of the Micro-LED array into a duty cycle distribution.
[0038] In a Micro-LED array, the optical power of each pixel varies. To improve the accuracy of the simulation, the optical power of each pixel is normalized to obtain optical duty cycle distribution data before calculating the power distribution parameters of each structural layer. Specifically, the pixel with the highest optical power in the Micro-LED array is set to 100%, while other pixels are calculated to be between 0% and 100%. The calculation method is as follows:
[0039] Duty cycle = Current pixel light power / Maximum pixel light power * 100%.
[0040] Based on the optical duty cycle distribution data, S30 obtains the power distribution parameters of different structural layers of each pixel in the Micro-LED array.
[0041] In this invention, the power distribution parameters of different structural layers at each pixel in the Micro-LED array include: obtaining the distribution data of LED optical power surface density, phosphor layer absorbed power volume density, LED thermal power volume density, and driving thermal power volume density at each pixel in the Micro-LED array based on optical duty cycle distribution data. Specifically:
[0042] LED optical power surface density = pixel light radiation power / pixel area;
[0043] Fluorescent layer absorption power volume density = Light radiation absorption power of the fluorescent layer at a pixel / (pixel area * fluorescent layer thickness);
[0044] LED thermal power volume density = thermal power of pixel chip layer / (pixel area * chip layer thickness);
[0045] Driven thermal power volume density = thermal power of pixel driving layer / (pixel area * driving layer thickness).
[0046] Because Micro-LEDs are small in size, the pixel area, phosphor layer area, and driver layer area are assumed to be the same during the calculation process. Therefore, the pixel area is used for the calculation of phosphor layer absorbed power volume density, LED thermal power volume density, and driver thermal power volume density.
[0047] The power distribution parameters of different structural layers of each pixel can be calculated using any existing method, such as editing the corresponding formula in Excel, etc. No specific limitations are made here.
[0048] S40 combines the feature coordinates of pixels to obtain a three-dimensional power density dataset of each pixel in the Micro-LED array, and imports it into Micro-LED thermal simulation software to map it to 3D data for thermal simulation.
[0049] For methods to obtain three-dimensional power density datasets, when the fluorescence surface is perpendicular to the coordinate axis, manual processing can be performed using Excel's pivot table function.
[0050] Taking a Micro-LED array containing 25,600 pixels as an example, the established coordinate system is as follows: Figure 2 and 3 As shown, the conversion process is as follows:
[0051] 1) Assuming the surface of the fluorescent layer ABCD is perpendicular to the x-axis, take 320 rows * 80 columns in Excel, totaling 25600 pixels. With point D as the origin of the local coordinate system, DB as the y' axis, and DC as the z' axis, calculate the y' value of each column and the z' value of each row.
[0052] 2) Use Excel's data conversion function to pivot the 320 rows * 80 columns into a dataset (z', y', optical power density) containing 25,600 two-dimensional optical power densities;
[0053] 3) Transform the two-dimensional power density dataset (z', y', optical power density) into a three-dimensional power density dataset (x, y, z, optical power density) in the Micro-LED array coordinate system. Example: If the origin D(0, 0) of the local coordinate system is (x1, y1, z1) in the whole lamp coordinate system, then x = x1, y = y' + y1, z = z' + z1;
[0054] 4) Similarly, the three-dimensional fluorescence layer absorption power volume density dataset is obtained, the difference being that x = x1 - AE;
[0055] 5) Similarly, the three-dimensional LED thermal power volume density dataset is obtained, the difference being that x = x1 - AF;
[0056] 6) Similarly, the three-dimensional driving thermal power volume density dataset is obtained, except that x = x1 - AG.
[0057] In addition to manually obtaining a 3D power density dataset using Excel's pivot table function, it can also be automatically generated using VBA code, specifically including:
[0058] S41 obtains the center coordinates of a pixel based on its feature coordinates.
[0059] Based on the center coordinates of the pixel, S42 further obtains the center coordinates of other pixels in the Micro-LED array;
[0060] S43 combines the center coordinates of each pixel with the power distribution parameters of different structural layers of each pixel in the Micro-LED array to obtain a three-dimensional power density dataset.
[0061] In one example, taking a Micro-LED array containing 25,600 pixels as an example, the established coordinate system is as follows: Figure 2 and 3 As shown, the following conversion process is automatically performed using VBA code, reducing the process time from 2400 seconds to 3 seconds compared to the manual processing method using Excel's pivot table function:
[0062] 1) Divide the Micro-LED array into 320*80 squares, with each square having a side length of 0.04mm;
[0063] 2) Calculate the center coordinates A' of the pixel containing A (the outermost vertex of the edge pixel of the Micro-LED array), offset it by 0.04mm in the AB direction to obtain the coordinates of the pixel in the 1st row and 2nd column, and so on until the center coordinates of the pixel in the 1st row and 320th column are obtained;
[0064] 3) Offset A' by 0.04mm in the AC direction to obtain the center coordinates of the 2nd row and 1st column, then offset it by 0.04mm in the AB direction to obtain the center coordinates of the 2nd row and 2nd column, and so on until the coordinates of the 2nd row and 320th column pixel are obtained;
[0065] 4) Following the methods in 2) and 3), the center coordinate set of 256 million pixels is obtained. The coordinates of these coordinates are then concatenated with the LED light power surface density in the order of their distribution to form a three-dimensional LED light power surface density dataset.
[0066] 5) Offset the center coordinate set obtained in 4) along the AE direction by the length of AE, and concatenate it with the fluorescence layer absorption power volume density in the distribution order to form a fluorescence layer absorption power volume density dataset.
[0067] 6) Offset the center coordinate set obtained in 4) by the length of AF in the AF direction, and concatenate it with the LED thermal power volume density in the distribution order to form a thermal power volume density dataset.
[0068] 7) Offset the center coordinate set obtained in 4) along the AG direction by the length of AG, and concatenate it with the driving thermal power volume density in the distribution order to form the driving thermal power volume density dataset.
[0069] 8) Write each power density dataset into csv or txt format.
[0070] Import the power density dataset in CSV or TXT format into the software and map it to the 3D data as a heat source boundary condition. Then, define other boundary conditions according to conventional thermal simulation methods, including: 1) defining the ambient temperature and heat transfer coefficient; 2) defining the materials and radiation surfaces of the chip layer, phosphor layer, driver layer, packaging, pads, etc.; 3) setting the mesh of each layer, etc., and performing calculations to complete the Micro-LED thermal simulation method.
[0071] This invention also provides a Micro-LED thermal simulation device applied to a Micro-LED array. Each pixel in the Micro-LED array includes a chip layer, a phosphor layer disposed on the light-emitting side surface of the chip layer, and a driving layer disposed on the electrode side of the chip layer. The Micro-LEDs are arranged in an array, such as... Figure 4As shown, the Micro-LED thermal simulation device includes: a feature coordinate acquisition module, used to establish a coordinate system based on the Micro-LED array and acquire the feature coordinates of a pixel, where the feature coordinates are: the coordinates of the vertex of any one of the chip layer, phosphor layer, and driving layer; and the midpoint coordinates of the phosphor layer, chip layer, and driving layer, which are the midpoint coordinates of the edge perpendicular to the phosphor layer along any vertex of each layer; an optical duty cycle distribution data acquisition module, used to normalize the luminous flux distribution of the Micro-LED array into a duty cycle distribution; a power distribution parameter acquisition module, used to obtain the power distribution parameters of different structural layers of each pixel in the Micro-LED array based on the optical duty cycle distribution data; and a three-dimensional power density dataset acquisition module, used to combine the feature coordinates of the pixel to obtain the three-dimensional power density dataset of each pixel in the Micro-LED array, and import it into the Micro-LED thermal simulation software to map it to 3D data for thermal simulation.
[0072] In this invention, thermal simulation is performed based on the three-layer structure of Micro-LED. Therefore, after establishing the coordinate system, the feature coordinate acquisition module also determines the feature coordinates of the pixel points based on the three-layer structure.
[0073] In a Micro-LED array, the optical power of each pixel varies. To improve simulation accuracy, before calculating the power distribution parameters of each structural layer, the optical duty cycle distribution data acquisition module normalizes the optical power of each pixel to obtain optical duty cycle distribution data. Specifically, the pixel with the highest optical power in the Micro-LED array is set to 100%, while other pixels are calculated to be between 0% and 100%, as follows:
[0074] Duty cycle = Current pixel light power / Maximum pixel light power * 100%.
[0075] The power distribution parameters of different structural layers at each pixel in a Micro-LED array include: based on the optical duty cycle distribution data, the distribution data of LED optical power surface density, phosphor layer absorbed power volume density, LED thermal power volume density, and driving thermal power volume density at each pixel in the Micro-LED array are obtained. Specifically:
[0076] LED optical power surface density = pixel light radiation power / pixel area;
[0077] Fluorescent layer absorption power volume density = Light radiation absorption power of the fluorescent layer at a pixel / (pixel area * fluorescent layer thickness);
[0078] LED thermal power volume density = thermal power of pixel chip layer / (pixel area * chip layer thickness);
[0079] Driven thermal power volume density = thermal power of pixel driving layer / (pixel area * driving layer thickness).
[0080] Due to the small size of Micro-LEDs, the calculation process assumes that the light-emitting area of the pixel, the area of the phosphor layer, and the area of the driving layer are the same. Therefore, the power distribution parameter acquisition module uses the pixel area for calculations of the phosphor layer's absorbed power volume density, the LED's thermal power volume density, and the driving thermal power volume density. The calculation of power distribution parameters for different structural layers of each pixel can be performed using any existing method, such as editing the corresponding formulas in Excel; no specific limitations are imposed here.
[0081] In the 3D power density dataset acquisition module, the method for converting the 3D power density dataset can be as follows: for cases where the fluorescence surface is perpendicular to the coordinate axis, manual processing using Excel's pivot table function can be used; alternatively, the 3D power density dataset can be automatically converted using VBA code (applicable to cases where the fluorescence surface is perpendicular or not perpendicular to the coordinate axis). The following conversion process is performed automatically using VBA code, which reduces the process time from 2400s to 3s compared to the manual processing method using Excel's pivot table function, greatly improving efficiency, reducing errors caused by manual operation, and improving accuracy.
[0082] It should be noted that the above embodiments can be freely combined as needed. The above are merely preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A method for thermal simulation of Micro-LEDs, characterized in that, Applied to Micro-LED arrays, where each pixel in the Micro-LED array includes a chip layer, a phosphor layer disposed on the light-emitting side surface of the chip layer, and a driving layer disposed on the electrode side of the chip layer, and the Micro-LEDs are arranged in an array, the Micro-LED thermal simulation method includes: A coordinate system is established based on the Micro-LED array, and the feature coordinates of one pixel are obtained. The feature coordinates are: the coordinates of the vertex of any one of the chip layer, phosphor layer and driving layer; and the midpoint coordinates of the phosphor layer, chip layer and driving layer are the midpoint coordinates of the edge of each layer perpendicular to the phosphor layer along any vertex. The light lumen distribution of the Micro-LED array is normalized to a duty cycle distribution; Based on the optical duty cycle distribution data, the power distribution parameters of different structural layers of each pixel in the Micro-LED array are obtained; By combining the feature coordinates of the pixels, a three-dimensional power density dataset of each pixel in the Micro-LED array is obtained, and then imported into Micro-LED thermal simulation software to map to 3D data for thermal simulation.
2. The Micro-LED thermal simulation method as described in claim 1, characterized in that, In obtaining the feature coordinates of one of the pixels, the feature coordinates include: the coordinates of each vertex on the side of the fluorescent layer away from the chip layer; and the midpoint coordinates of the fluorescent layer, the chip layer, and the driving layer, which are the midpoint coordinates of the edge of each layer perpendicular to the fluorescent layer along any vertex.
3. The Micro-LED thermal simulation method as described in claim 1 or 2, characterized in that, Based on the optical duty cycle distribution data, the power distribution parameters of different structural layers of each pixel in the Micro-LED array are obtained, including: the distribution data of LED optical power surface density, phosphor layer absorbed power volume density, LED thermal power volume density and driving thermal power volume density of each pixel in the Micro-LED array.
4. The Micro-LED thermal simulation method as described in claim 3, characterized in that, The LED optical power surface density = pixel light radiation power / pixel area; The volume density of the fluorescent layer absorption power = the light radiation absorption power of the fluorescent layer at each pixel / (pixel area * fluorescent layer thickness); The LED thermal power volume density = thermal power of the pixel chip layer / (pixel area * chip layer thickness); The driving thermal power volume density = thermal power of the pixel driving layer / (pixel area * driving layer thickness).
5. The Micro-LED thermal simulation method as described in claim 1, 2, or 4, characterized in that, By combining the feature coordinates of the pixels, a three-dimensional power density dataset of each pixel in the Micro-LED array is obtained, including: Based on the feature coordinates of the pixel, the center coordinates of the pixel are obtained; Based on the center coordinates of the pixel, the center coordinates of other pixels in the Micro-LED array are further obtained; The three-dimensional power density dataset is obtained by combining the center coordinates of each pixel and the power distribution parameters of different structural layers of each pixel in the Micro-LED array.
6. The Micro-LED thermal simulation method as described in claim 5, characterized in that, By combining the feature coordinates of the pixels, the three-dimensional power density dataset of each pixel in the Micro-LED array is obtained, and the three-dimensional power density dataset is automatically converted by VBA code.
7. A Micro-LED thermal simulation device, characterized in that, Applied to Micro-LED arrays, wherein each pixel in the Micro-LED array includes a chip layer, a phosphor layer disposed on the light-emitting side surface of the chip layer, and a driving layer disposed on the electrode side of the chip layer, and the Micro-LEDs are arranged in an array, the Micro-LED thermal simulation device includes: The feature coordinate acquisition module is used to establish a coordinate system based on the Micro-LED array and acquire the feature coordinates of a pixel. The feature coordinates are: the coordinates of the vertex of any one of the chip layer, phosphor layer and driving layer; and the midpoint coordinates of the phosphor layer, chip layer and driving layer are the midpoint coordinates of the edge of each layer perpendicular to the phosphor layer along any vertex. The optical duty cycle distribution data acquisition module is used to normalize the light lumen distribution of the Micro-LED array into a duty cycle distribution; The power distribution parameter acquisition module is used to obtain the power distribution parameters of different structural layers of each pixel in the Micro-LED array based on the optical duty cycle distribution data. The three-dimensional power density dataset acquisition module is used to combine the feature coordinates of the pixel points to obtain the three-dimensional power density dataset of each pixel point in the Micro-LED array, and import it into the Micro-LED thermal simulation software to map it to 3D data for thermal simulation.
8. The Micro-LED thermal simulation device as described in claim 7, characterized in that, In the power distribution parameter acquisition module, the distribution data of LED optical power surface density, phosphor layer absorbed power volume density, LED thermal power volume density and driving thermal power volume density of each pixel in the Micro-LED array are obtained based on the optical duty cycle distribution data.
9. The Micro-LED thermal simulation device as described in claim 7 or 8, characterized in that, The three-dimensional power density dataset acquisition module includes: The center coordinate calculation unit is used to obtain the center coordinates of the pixel based on the feature coordinates of the pixel; and to further obtain the center coordinates of other pixels in the Micro-LED array based on the center coordinates of the pixel. The three-dimensional power density data calculation unit is used to combine the center coordinates of each pixel and the power distribution parameters of different structural layers of each pixel in the Micro-LED array to obtain the three-dimensional power density dataset.
10. The Micro-LED thermal simulation device as described in claim 9, characterized in that, In the three-dimensional power density dataset acquisition module, the three-dimensional power density dataset is automatically obtained through VBA code conversion.