Method of chroma compensation for pixels and microled display used in the same
Patent Information
- Application Number
- TW114106658
- Authority / Receiving Office
- TW · TW
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2025-02-24
- Publication Date
- 2026-09-01
- Estimated Expiration
- 2045-02-23
AI Technical Summary
Micro LED displays face challenges in brightness and color uniformity due to variations in optical characteristics of chips, leading to low yield and increased production costs, and randomly mixing chips results in noticeable color differences.
A pixel chromaticity compensation method where pixels are driven sequentially, and their dominant wavelengths are measured and adjusted to achieve uniform color mixing by varying brightness levels of adjacent sub-pixels.
Enhances color uniformity by adjusting dominant wavelengths to match minimum, maximum, or average values, improving display quality and reducing waste.
Smart Images
Figure TWG2TA001073888_001 
Figure TWG2TA001073888_002 
Figure TWG2TA001073888_003
Abstract
Description
Technical Field
[0001] This disclosure relates to a pixel chromaticity compensation method and a display of the micro light-emitting diode thereof, particularly to a method for compensating for the primary color light with other colors of light and a display using the method. Prior Technology
[0002] In the field of light-emitting diode (LED) technology, LEDs have been developed that shrink the size of traditional LEDs to the micrometer level; these are called micro LEDs (μLEDs). When micro LEDs are used in display technology, each micro LED can be considered a sub-pixel in a display panel, and such a display panel is called a micro LED display. Due to its advantages such as high luminous efficiency, long lifespan, and high resolution, micro LED displays are considered the next mainstream display technology.
[0003] The epitaxial growth process for Micro LEDs employs techniques such as metal-organic chemical vapor deposition (MOCVD) to grow the light-emitting structure layer on a supporting substrate. Due to variations in production conditions and raw materials during the epitaxial growth process, each Micro LED chip exhibits differences in optical characteristics. However, the requirements for brightness and color uniformity of Micro LED chips in Micro LED displays are becoming increasingly stringent, particularly for head-mounted displays where color difference must be eliminated within small areas.
[0004] Therefore, after optical characteristic testing, some grades or binaries of Micro LED chips are unusable, resulting in a very low yield and significantly increased production costs. On the other hand, to ensure that most grades or binaries of chips can be used, chips of different grades or binaries are randomly placed on the display substrate containing the driving circuit. However, this method of randomly mixing chips can easily lead to large color differences when adjacent pixels display the same single color of light (e.g., all pixels display only red light), making it easy to see noise in the image. Summary of the Invention
[0005] In one aspect disclosed herein, a pixel chromaticity compensation method is provided, comprising: driving a first pixel, a second pixel, and a third pixel of a display with a micro light-emitting diode to emit light sequentially; measuring a first dominant wavelength of the first pixel, a second dominant wavelength of the second pixel, and a third dominant wavelength of the third pixel in each pixel; and driving the second pixel or the third pixel in each pixel to emit light at a partial brightness to mix with the first pixel in the same pixel emitting light at the first dominant wavelength, wherein the color matching of the mixed light will be manifested as an adjusted first dominant wavelength, the adjusted first dominant wavelength approaching a minimum, a maximum, or an average value among the measured first dominant wavelengths.
[0006] In another state disclosed herein, when the first pixel is a red sub-pixel and the second pixel is a green sub-pixel, the red sub-pixel emits red light with a red dominant wavelength, and the green sub-pixel in the same pixel emits green light with a partial brightness and a green dominant wavelength, the color matching of the light after the red light and the green light are mixed will be manifested as an adjusted red dominant wavelength, which is close to the minimum value among the measured first dominant wavelengths.
[0007] In another state disclosed herein, when the first pixel is a blue subpixel and the second pixel is a green subpixel, the blue subpixel emits blue light with a dominant blue wavelength, and the green subpixel in the same pixel emits green light with a dominant green wavelength at a partial brightness, the color matching of the light after the blue light and the green light are mixed will be manifested as an adjusted dominant blue wavelength, which is close to the maximum value among the measured first dominant wavelengths.
[0008] In another state disclosed herein, when the first pixel is a green subpixel, the second pixel is a blue subpixel, and the third pixel is a red subpixel, the green subpixel emits green light with a dominant green wavelength, and the blue subpixel in the same pixel emits blue light with a partial brightness and a dominant blue wavelength, the color matching of the light after the green light and the blue light are mixed will be manifested as an adjusted dominant green wavelength, which is close to the average value of each of the first dominant wavelengths that have been measured.
[0009] In another state disclosed herein, when the first pixel is a green subpixel, the second pixel is a blue subpixel, and the third pixel is a red subpixel, the green subpixel emits green light with a dominant green wavelength, and the red subpixel in the same pixel emits red light with a partial brightness and a dominant red wavelength, the color matching of the light after the green light and the red light are mixed will be manifested as an adjusted dominant green wavelength, which is close to the average value of each of the first dominant wavelengths that have been measured.
[0010] In one embodiment disclosed herein, a miniature light-emitting diode display is provided, comprising: a plurality of pixels, each pixel including a red subpixel, a green subpixel, and a blue subpixel; a storage unit storing a first dominant wavelength of one of the red subpixels, a second dominant wavelength of one of the green subpixels, and a third dominant wavelength of one of the blue subpixels, and storing a maximum first dominant wavelength of each of the first dominant wavelengths, a maximum second dominant wavelength of each of the second dominant wavelengths, and a maximum third dominant wavelength of each of the third dominant wavelengths; and a driving circuit configured to drive one of the red, green, and blue subpixels in each pixel to emit light at full brightness, while simultaneously driving the other or both to emit light at partial brightness, such that the color matching of the mixed light will be represented by an adjusted dominant wavelength, and the adjusted dominant wavelengths are approximately the same.
[0011] In another aspect disclosed herein, the red subpixel emits red light at full brightness with a dominant red wavelength, and the green subpixel in the same pixel emits green light at partial brightness with a dominant green wavelength. The color matching of the light after the red light and the green light are mixed will be manifested as an adjusted dominant red wavelength, which approaches a minimum value among the first dominant wavelengths.
[0012] In another embodiment disclosed herein, the blue subpixel emits blue light at full brightness with a dominant blue light wavelength, and the green subpixel in the same pixel emits green light at partial brightness with a dominant green light wavelength. The color matching of the light after the blue light and the green light are mixed will be manifested as an adjusted dominant blue light wavelength, which is close to a maximum value among the third dominant wavelengths.
[0013] In another embodiment disclosed herein, the green subpixel emits green light at full brightness with a dominant green wavelength, and the blue subpixel in the same pixel emits blue light at partial brightness with a dominant blue wavelength. The color matching of the light after the green light and the blue light are mixed will be manifested as an adjusted dominant green wavelength, which is close to an average value among the second dominant wavelengths.
[0014] In another embodiment disclosed herein, the green subpixel emits green light at full brightness with a dominant green wavelength, and the red subpixel in the same pixel emits red light at partial brightness with a dominant red wavelength. The color matching of the light after the green light and the red light are mixed will be manifested as an adjusted dominant green wavelength, which is close to an average value among the second dominant wavelengths. Simple Explanation of the Diagram
[0015] To fully understand the nature, advantages, and preferred embodiments of this disclosure, the following detailed description can be understood more clearly by referring to the accompanying drawings.
[0016] Figures 1A and 1B are schematic diagrams depicting a display of a miniature light-emitting diode according to an embodiment of the present disclosure.
[0017] Figures 2A-2C are schematic diagrams depicting the wavelength matching of red and green light after mixing, according to an embodiment of the present disclosure.
[0018] Figures 3A-3C are schematic diagrams depicting the wavelength matching of blue and green light after mixing, according to an embodiment of the present disclosure.
[0019] Figures 4A-4C are schematic diagrams depicting the wavelength matching of green and blue light after mixing, according to an embodiment of the present disclosure.
[0020] Figures 5A-5C are schematic diagrams depicting the wavelength matching of color after mixing green light and bright light according to an embodiment of the present disclosure.
[0021] Figure 6 is a flowchart depicting a pixel chromaticity compensation method according to an embodiment of the present disclosure. Implementation
[0022] The following description illustrates preferred embodiments of the present disclosure. The disclosure will be described below with reference to embodiments and drawings. Therefore, the disclosure is not intended to be limited to the shown embodiments, but rather to conform to the principles disclosed herein. Furthermore, those skilled in the art will be able to make various modifications or variations based on the disclosure and incorporate them into the spirit and scope of this document and the appended claims.
[0023] In this disclosure, the use of terms such as first, second, and third, etc., is understood to be for describing various elements, components, regions, layers, and / or blocks. However, these elements, components, regions, layers, and / or blocks should not be limited by these terms. These terms are limited to identifying individual elements, components, regions, layers, and / or blocks only. Therefore, a first element, component, region, layer, and / or block in the following text may also be referred to as a second element, component, region, layer, and / or block without departing from the intent of this disclosure.
[0024] Figures 1A and 1B are schematic diagrams depicting a display of a miniature light-emitting diode according to an embodiment of the present disclosure. The display 10 includes a substrate 11, a plurality of pixels 12 disposed on the substrate 11, a driving circuit 13, and a storage unit 14. The driving circuit 13 drives the red sub-pixel 12R, green sub-pixel 12G, and blue sub-pixel 12B of each pixel 12 to emit light at full brightness in sequence (only the same sub-pixel emits light at the same time). An optical instrument (not shown) is used to measure the first dominant wavelength of the red sub-pixel 12R, the second dominant wavelength of the green sub-pixel 12G, and the third dominant wavelength of the blue sub-pixel 13B of each pixel 12, and stores the position of each sub-pixel and the corresponding first dominant wavelength, second dominant wavelength, or third dominant wavelength in the storage unit 14.
[0025] Referring to Figure 1A, in each pixel 12 of the display 10, the red subpixel 12R is driven to emit light, while the green subpixel 12G and the blue subpixel 12B are completely dark. As mentioned earlier, when adjacent pixels 12 display the same single red light, most of the red subpixels 12R exhibit chromaticity C1, while the red light of other red subpixels 12R exhibits different chromaticities C2 and C3.
[0026] Referring again to Figure 1B, the driving circuit 13 of the display 10 drives the red sub-pixels 12R in each pixel 12 to emit red light at full brightness, which has a dominant red light wavelength. At the same time, it drives the green sub-pixels 12G in the same pixel 12R to emit green light with a dominant green light wavelength at partial brightness. The color match of the light after the red light and green light are mixed will be represented by an adjusted dominant red light wavelength. The adjusted dominant red light wavelength is close to the minimum value of each first dominant wavelength recorded in the storage unit 14. Therefore, the red light of each red sub-pixel 12R presents chromaticity C3.
[0027] Similarly, the blue sub-pixel 12B in each pixel 12 emits blue light at full brightness with a dominant blue light wavelength, and the green sub-pixel 12G in the same pixel 12 emits green light at partial brightness with a dominant green light wavelength. The color matching of the light after the blue light and the green light are mixed will be manifested as an adjusted dominant blue light wavelength, which is close to a maximum value among the third dominant wavelengths.
[0028] Furthermore, there are two ways to adjust the color matching of the green light of the green sub-pixel 12G, as follows: (1) Drive the green sub-pixel 12G in each pixel 12 to emit green light at full brightness with a green light main wavelength, and the blue sub-pixel 12B in the same pixel 12 to emit blue light at partial brightness with a blue light main wavelength. The color matching of the light after the green light and the blue light are mixed will be expressed as an adjusted green light main wavelength. The adjusted green light main wavelength is close to the average value of each of the second main wavelengths; (2) Drive the green sub-pixel 12G in each pixel 12 to emit green light at full brightness with a green light main wavelength, and the red sub-pixel 12R in the same pixel 12 to emit red light at partial brightness with a red light main wavelength. The color matching of the light after the green light and the red light are mixed will be expressed as an adjusted green light main wavelength. The adjusted green light main wavelength is close to the average value of each of the second main wavelengths.
[0029] Figures 2A-2C are schematic diagrams illustrating the wavelength matching of color after mixing red and green light according to an embodiment of the present disclosure. Figure 2A shows a red subpixel 12R emitting red light with a dominant wavelength of 620nm, and a green subpixel 12G in the same pixel 12 emitting green light with a dominant wavelength of 510nm at partial brightness, as shown in Figure 2B. Referring to Figure 2C, the color matching after mixing red and green light will manifest as an adjusted dominant wavelength of 615nm for red light, which is the minimum value among the first dominant wavelengths recorded in storage unit 14.
[0030] Figures 3A-3C are schematic diagrams illustrating the wavelength matching of color after mixing blue and green light according to an embodiment of the present disclosure. Figure 3A shows a blue subpixel 12B emitting blue light with a dominant wavelength of 460nm, and a green subpixel 12G in the same pixel 12 emitting green light with a dominant wavelength of 510nm at a partial brightness, as shown in Figure 3B. Referring to Figure 3C, the color matching after mixing blue and green light will manifest as an adjusted dominant blue wavelength of 465nm, which is the maximum value among the third dominant wavelengths recorded in storage unit 14.
[0031] Figures 4A-4C are schematic diagrams illustrating the wavelength matching of color after mixing green and blue light according to an embodiment of this disclosure. Figure 4A shows a green subpixel 12G emitting green light with a dominant wavelength of 510nm, and a blue subpixel 12B in the same pixel 12 emitting blue light with a dominant wavelength of 460nm at a partial brightness, as shown in Figure 4B. Referring to Figure 4C, the color matching after mixing green and blue light will be manifested as an adjusted dominant green wavelength of 505nm, that is, an average value of each second dominant wavelength recorded in storage unit 14.
[0032] Figures 5A-5C are schematic diagrams illustrating the wavelength matching of color after mixing green light and red light according to an embodiment of this disclosure. Figure 5A shows a green subpixel 12G emitting green light with a dominant wavelength of 500nm, and a red subpixel 12R in the same pixel 12 emitting red light with a dominant wavelength of 620nm at partial brightness, as shown in Figure 5B. Referring to Figure 5C, the color matching after mixing green light and red light will be manifested as an adjusted dominant wavelength of green light of 505nm, that is, an average value of each second dominant wavelength recorded in storage unit 14.
[0033] Figure 6 is a flowchart depicting a pixel chromaticity compensation method according to an embodiment of the present disclosure. In step 601 of flowchart 600, a first pixel, a second pixel, and a third pixel of a display with a micro-light-emitting diode are driven to emit light sequentially. An optical instrument (not shown) is used to measure the first dominant wavelength of the first pixel, the second dominant wavelength of the second pixel, and the third dominant wavelength of the third pixel, as shown in step 602. Furthermore, the position of each sub-pixel and its corresponding first, second, or third dominant wavelength can be stored.
[0034] Referring to step 603, drive the second or third pixel in each pixel to emit light with partial brightness to mix with the first pixel in the same pixel to emit light with the first dominant wavelength. The color matching of the mixed light will be represented by an adjusted first dominant wavelength, which is close to a minimum, a maximum or an average value among the measured first dominant wavelengths.
[0035] As described in the previous embodiment, according to the execution content of step 603, when the first pixel is a red sub-pixel and the second pixel is a green sub-pixel, the red sub-pixel emits red light with a red light main wavelength, and the green sub-pixel in the same pixel emits green light with a green light main wavelength at a partial brightness. The color matching of the light after the red light and the green light are mixed will be manifested as an adjusted red light main wavelength. The adjusted red light main wavelength is close to the minimum value among the measured first main wavelengths.
[0036] Furthermore, according to the execution content of step 603, when the first pixel is a blue sub-pixel and the second pixel is a green sub-pixel, the blue sub-pixel emits blue light with a blue dominant wavelength, and the green sub-pixel in the same pixel emits green light with a green dominant wavelength at a partial brightness, the color matching of the light after the blue light and the green light are mixed will be manifested as an adjusted blue dominant wavelength, which is close to the maximum value among the measured first dominant wavelengths.
[0037] Furthermore, according to the execution content of step 603, when the first pixel is a green sub-pixel, the second pixel is a blue sub-pixel, and the third pixel is a red sub-pixel, the green sub-pixel emits green light with a dominant green wavelength, and the blue sub-pixel in the same pixel emits blue light with a partial brightness and a dominant blue wavelength, the color matching of the light after the green light and the blue light are mixed will exhibit an adjusted dominant green wavelength, which is close to the average value of the measured first dominant wavelengths. Alternatively, when the green sub-pixel emits green light with a dominant green wavelength, and the red sub-pixel in the same pixel emits red light with a partial brightness and a dominant red wavelength, the color matching of the light after the green light and the red light are mixed will exhibit an adjusted dominant green wavelength, which is close to the average value of the measured first dominant wavelengths.
[0038] Although this disclosure is written with respect to embodiments and implementations with fish bodies, various changes and modifications will be made by those skilled in the art. The aim is to include such changes and modifications that fall within the scope of the appended claims.
[0039] 10: Monitor 11:Substrate 12 pixels 13: Drive circuit 14: Storage Unit 600: Flowchart 601: Steps 602: Steps 603: Steps 12B: Blue subpixel 12R: Red subpixel 12G: Green Subpixel C1, C2, C3: Chromaticity
Claims
1. A pixel color compensation method, comprising: driving a first pixel, a second pixel, and a third pixel of a display of a micro light-emitting diode to emit light sequentially; measuring a first dominant wavelength of the first pixel, a second dominant wavelength of the second pixel, and a third dominant wavelength of the third pixel in each pixel; and driving the second pixel or the third pixel in each pixel to emit light at a partial brightness to mix with the first pixel in the same pixel emitting light at the first dominant wavelength, wherein the color matching of the mixed light will be represented by an adjusted first dominant wavelength, the adjusted first dominant wavelength approaching a minimum, a maximum, or an average value of the measured first dominant wavelengths.
2. The method as described in claim 1, wherein when the first pixel is a red sub-pixel and the second pixel is a green sub-pixel, the red sub-pixel emits red light with a red dominant wavelength, and the green sub-pixel in the same pixel emits green light with a partial brightness and a green dominant wavelength, the color matching of the light after the red light and the green light are mixed will be manifested as an adjusted red dominant wavelength, the adjusted red dominant wavelength approaching the minimum value among the measured first dominant wavelengths.
3. The method as described in claim 1, wherein when the first pixel is a blue subpixel and the second pixel is a green subpixel, the blue subpixel emits blue light with a dominant blue wavelength, and the green subpixel in the same pixel emits green light with a dominant green wavelength at a partial brightness, the color matching of the light after the blue light and the green light are mixed will be manifested as an adjusted dominant blue wavelength, the adjusted dominant blue wavelength approaching the maximum value among the measured first dominant wavelengths.
4. The method as described in claim 1, wherein when the first pixel is a green subpixel, the second pixel is a blue subpixel, and the third pixel is a red subpixel, the green subpixel emits green light with a dominant green wavelength, and the blue subpixel in the same pixel emits blue light with a dominant blue wavelength at a partial brightness, the color matching of the light after the green light and the blue light are mixed will be manifested as an adjusted dominant green wavelength, the adjusted dominant green wavelength being close to the average value of each of the measured first dominant wavelengths.
5. The method as described in claim 1, wherein when the first pixel is a green subpixel, the second pixel is a blue subpixel, and the third pixel is a red subpixel, the green subpixel emits green light with a dominant green wavelength, and the red subpixel in the same pixel emits red light with a partial brightness and a dominant red wavelength, the color matching of the light after the green light and the red light are mixed will be manifested as an adjusted dominant green wavelength, the adjusted dominant green wavelength being close to the average value of each of the measured first dominant wavelengths.
6. A display of a miniature light-emitting diode, comprising: a plurality of pixels, each pixel including a red subpixel, a green subpixel, and a blue subpixel; a storage unit storing a first dominant wavelength of one of the red subpixels, a second dominant wavelength of one of the green subpixels, and a third dominant wavelength of one of the blue subpixels, and storing a maximum first dominant wavelength of the first dominant wavelength, a maximum second dominant wavelength of the second dominant wavelength, and a maximum third dominant wavelength of the third dominant wavelength; and a driving circuit configured to: drive one of the red subpixels, the green subpixels, and the blue subpixels in each pixel to emit light at full brightness, while simultaneously driving the other one or the other two to emit light at partial brightness, wherein the color matching of the mixed light will be represented by an adjusted dominant wavelength, and the adjusted dominant wavelengths are approximately the same.
7. The display as claimed in claim 6, wherein the red subpixel emits red light at full brightness and has a red dominant wavelength, and the green subpixel in the same pixel emits green light at partial brightness and has a green dominant wavelength, and the color matching of the light after the red light and the green light are mixed will be manifested as an adjusted red dominant wavelength, which is close to a minimum value among the first dominant wavelengths.
8. The display as claimed in claim 6, wherein the blue subpixel emits blue light at full brightness with a dominant blue light wavelength, and the green subpixel in the same pixel emits green light at partial brightness with a dominant green light wavelength, and the color matching of the light after the blue light and the green light are mixed will be manifested as an adjusted dominant blue light wavelength, the adjusted dominant blue light wavelength being close to a maximum value among the third dominant wavelengths.
9. The display as claimed in claim 6, wherein the green subpixel emits green light at full brightness with a dominant green wavelength, and the blue subpixel in the same pixel emits blue light at partial brightness with a dominant blue wavelength, and the color matching of the light after the green light and the blue light are mixed will be manifested as an adjusted dominant green wavelength, the adjusted dominant green wavelength being close to an average value among the second dominant wavelengths.
10. The display as claimed in claim 6, wherein the green subpixel emits green light at full brightness with a dominant green wavelength, and the red subpixel in the same pixel emits red light at partial brightness with a dominant red wavelength, and the color matching of the light after the green light and the red light are mixed will be manifested as an adjusted dominant green wavelength, the adjusted dominant green wavelength being close to an average value among the second dominant wavelengths.