Inspection tool for inspecting micro-led array panel

Abstract

An inspection tool for inspecting a micro LED array panel (00) includes a light collector set (01) configured to collect light emitted from a micro LED array included in the micro LED array panel (00), an image detector (02) connected with the light collector set (01) to receive the light collected by the light collector set (01) and configured to capture an image of the micro LED array, and a light measurement device (03) electrically connected with the light collector set (01) to receive the light collected by the light collector set (01) and configured to measure light emitted from one or more portions of the micro LED array. The light collector set (01) is configured to receive light emitted from any location of the micro LED array.

Description

Technical Field

[0001] This disclosure generally relates to the field of light-emitting diode technology, and more particularly to an inspection tool for inspecting micro light-emitting diode (LED) array panels. Background Technology

[0002] Micro-LEDs, with their ultra-small area and high resolution, are becoming increasingly popular worldwide. Micro-LED array panels can be used to form various types of devices, such as camera modules, projection modules, display modules, VR / AR optical modules, etc.

[0003] However, because the images and light-emitting areas displayed by microLED array panels are much smaller than before, pixel defects in microLED array panels are not easily detected and identified using conventional methods. Therefore, operators need to view the wafers, chips, and masks through a graphical user interface that displays various pattern images of the microLED panel to identify pattern defects.

[0004] Furthermore, the light-emitting area of ​​the micro-LED array panel is very small, for example, 3mm × 5mm. However, the light collector used to collect the light emitted by the micro-LED array on the panel cannot have a collection area as small as the light-emitting area of ​​the micro-LED array panel due to the various optical components within the light collector. Therefore, the image acquisition process and the light collection process cannot be performed simultaneously. Moreover, if the image acquisition and light collection processes are performed simultaneously, the light entering the light collector will be weakened, thereby reducing image accuracy and measurement accuracy.

[0005] The above content is only used to help understand the technical solution of this application and does not constitute an admission that the above content is prior art. Summary of the Invention

[0006] To overcome the above-mentioned shortcomings, this disclosure provides an inspection tool for inspecting micro-LED array panels to improve inspection efficiency and accuracy.

[0007] To achieve the above objectives, this disclosure provides an inspection tool for inspecting microLED array panels to increase the amount of light entering the light collector.

[0008] An inspection tool for inspecting micro light-emitting diode (LED) array panels according to this disclosure includes:

[0009] A light collector group is configured to collect light emitted from a microLED array included in a microLED array panel;

[0010] An image detector, connected to a light collector array to receive light collected by the light collector array, and configured to capture an image of the microLED array; and

[0011] A light measurement device, electrically connected to a light collector group to receive light collected by the light collector group, and configured to measure light emitted from one or more portions of a microLED array.

[0012] The light collector array is configured to receive light emitted from any location on the microLED array.

[0013] In some embodiments, the light collector group includes a first light collector and a second light collector, wherein the first light collector is connected to an image detector; the second light collector is electrically connected to a light measurement device; the first light collector is disposed above and vertically aligned with the microLED array; and the first light collector is configured to guide light emitted from the microLED array to the image detector.

[0014] In some implementations, one or more portions of the second light collector have a concave surface facing the microLED array panel.

[0015] In some embodiments, the second light collector is configured to include at least one or more concave surfaces on one side or around the first light collector and above the microLED array panel, with the microLED array panel disposed at the center of the concave surface for collecting light emitted from one or more portions of the microLED array.

[0016] In some implementations, the second light collector is not connected to the first light collector and does not contact the sidewall of the first light collector.

[0017] In some implementations, a light transmission channel is configured between the first light collector and the image detector, wherein the second light collector is configured to include at least one or more sides of the light transmission channel or around the light transmission channel and above the microLED array panel, the microLED array panel being arranged at the center of the concave surface, the concave surface being used to collect light emitted from one or more portions of the microLED array.

[0018] In some implementations, the second optical collector is not connected to the optical transmission channel and does not contact the sidewall of the optical transmission channel.

[0019] In some implementations, a filter is configured between the first light collector and the image detector.

[0020] In some embodiments, the second light collector is configured to include at least one or more concave surfaces on one side or around the microLED array panel, with the microLED array panel disposed at the center of the concave surface for collecting light emitted from one or more portions of the microLED array.

[0021] In some implementations, the second light collector is an integrating hemisphere, with a micro-LED array panel disposed at the center of the hemisphere; wherein an opening is formed at the top of the hemisphere for inserting the first light collector.

[0022] In some implementations, the entire surface of the second light collector is curved.

[0023] In some implementations, the detection area of ​​the first light collector is not less than the emitting area of ​​the microLED array.

[0024] In some implementations, the detection area of ​​the second light collector is larger than the light-emitting area of ​​the microLED array.

[0025] In some implementations, the detection area of ​​the second light collector is less than or equal to the emitting area of ​​the microLED array.

[0026] To achieve the above objectives, the inspection system for inspecting microLED array panels includes at least the aforementioned inspection tools.

[0027] In some embodiments, the light collector group includes a first light collector and a second light collector, wherein the first light collector is connected to an image detector; and the second light collector is connected to a light measurement device; the first light collector is disposed above and vertically aligned with the microLED array; and the first light collector is configured to guide light emitted from the microLED array to the image detector.

[0028] In some implementations, the testing system also includes a sample stage for supporting the microLED array panel.

[0029] In some implementations, the second light collector is mounted on the sample stage.

[0030] Many other advantages and features of this disclosure will become even more apparent from the following detailed description and accompanying drawings. Attached Figure Description

[0031] Figure 1 This is a block diagram of an inspection tool for inspecting microLED array panels according to one embodiment of the present disclosure.

[0032] Figures 2 to 25 This is a schematic diagram illustrating the structure of a testing tool according to various embodiments of the present disclosure. Detailed Implementation

[0033] A further understanding of this disclosure will now be provided with reference to preferred embodiments. The specific embodiments and drawings discussed are merely illustrative of how this disclosure is made and used, and do not limit the scope of this disclosure or the appended claims.

[0034] Reference Figure 1 and Figure 2 According to one embodiment of this disclosure, an inspection tool for inspecting a microLED array panel includes:

[0035] Light collector group 01 is configured to collect light emitted from a microLED array included in microLED array panel 00;

[0036] Image detector 02, connected to light collector group 01 to receive light collected by light collector group 01, and configured to capture images of the microLED array; and

[0037] The light measurement device 03 is electrically connected to the light collector group 01 to receive light collected by the light collector group, for detecting light emitted from one or more parts of the microLED array;

[0038] Among them, the light collector group 01 is configured to receive light emitted from any position of the microLED array.

[0039] Furthermore, the image detector 02 may include, but is not limited to, a charge-coupled device detector, a photomultiplier tube detector, etc. The optical measurement device 03 may include, but is not limited to, a spectrometer. The optical measurement device 03 can measure any optical parameter of the emitted light, such as full width at half maximum (FWHM) and peak width.

[0040] The light collector group 01 includes a first light collector 101 and a second light collector 102, wherein the first light collector 101 is connected to the image detector 02; and the second light collector 102 is electrically connected to the light measurement device 03; the first light collector 101 is disposed above the micro-LED array panel 00 and vertically aligned with the micro-LED array panel 00; the first light collector 101 guides the light emitted from the micro-LED array panel 00 to the image detector 02.

[0041] Furthermore, one or more portions of the second light collector 102 include a concave surface facing the microLED array panel 00. The concave surface may have an inwardly concave shape, similar to a portion of the rim of a plate or bowl. Preferably, the entire surface of the second light collector 102 may be curved. In this document, the first light collector 101 includes various optical elements for collecting and guiding light emitted from the microLED array. These optical elements may include lenses, mirrors, filters, beam splitters, etc. For example, see reference... Figure 2 A filter 104 may be arranged in the optical path between the first light collector 101 and the image detector 02 to filter out unexpected light or reduce light intensity. It should be noted that the second light collector 102 may be electrically connected to the optical measurement device 03 via a conductive line 06. The conductive line 06 may include an optical fiber. In some embodiments, the second light collector may include a light converging device that converges the light collected by the concave surface to the end of the conductor 06.

[0042] Reference Figure 3 and Figure 4 The second light collector 102 is configured to include at least one or more concave surfaces below or around the bottom of the first light collector 101 and above the microLED array panel 00; and the concave surfaces are used to collect light emitted from one or more portions of the microLED array. For example, as Figure 3 As shown, Figure 3 This is a cross-sectional view of an inspection tool according to one embodiment, showing that the second light collector 102 includes a portion of a concave surface below one side of the first light collector 101. As another example, such as... Figure 4 As shown, Figure 4 This is a cross-sectional view of an inspection tool according to another embodiment. The second light collector 102 includes a concave surface surrounding the bottom of the first light collector 101. Furthermore, the second light collector 102 is not connected to the first light collector 101 and does not contact the sidewalls of the first light collector 101. (See also...) Figure 5 and Figure 6 The second light collector 102 can be mounted on the sample stage 04 used to support the microLED array panel 00. (Refer to...) Figure 7 and Figure 8 The second light collector 102 can be mounted on the first light collector 101. Preferably, at least one point or center of the micro-LED array panel 00 is arranged at the center of the concave surface.

[0043] In addition, refer to Figure 9 and Figure 10 The second light collector 102 is configured to include a concave surface on one or more sides of the microLED array panel 00 or around the microLED array panel 00; preferably, the microLED array panel 00 is arranged at the center of the concave surface for collecting light emitted from one or more portions of the microLED array. Preferably, the concave surface is hemispherical. It should be noted that the bottom of the second light collector 102 may be lower than the bottom of the microLED array panel 00.

[0044] In addition, refer to Figure 11 The second light collector 102 is a sphere. For example, the second light collector 102 can be an integrating hemisphere; preferably, the micro-LED array panel 00 is disposed at the center of the hemisphere. In this document, an opening is formed at the top of the sphere for inserting the first light collector 101.

[0045] Reference Figure 12 and Figure 13The second light collector 102 is configured to include a concave surface on one or more sides of the first light collector 101, or around the first light collector 101 and above the microLED array panel 00; and the concave surface is used to collect light emitted from one or more portions of the microLED array. Furthermore, the second light collector 102 is not connected to the first light collector 101 and does not contact the sidewalls of the first light collector 101. Preferably, the microLED array panel 00 is arranged at the center of the concave surface. (Refer to...) Figures 14 to 17 The second light collector 102 can be mounted on the first light collector 101 or on the sample stage 04 used to support the microLED array panel 00.

[0046] In addition, refer to Figure 18 and Figure 19 An optical transmission channel 103 is configured between the first light collector 101 and the image detector 02. For example... Figure 18 and Figure 19 As shown, the second light collector 102 is configured to include a concave surface on one or more sides of the light transmission channel 103, or around the light transmission channel 103 and above the micro-LED array panel 00; preferably, the micro-LED array panel 00 is arranged at the center of the concave surface, and the second light collector 102 is used to collect light emitted from one or more portions of the micro-LED array. Furthermore, the second light collector 102 is not connected to the light transmission channel 103 and does not contact the sidewalls of the light transmission channel 103. (Refer to...) Figures 20 to 23 The second light collector 102 can be mounted on the light transmission channel 103 or on the sample stage 04 used to support the microLED array panel 00. Furthermore, the second light collector 102 can be configured to include a concave surface around the light transmission channel 103 and above the microLED array panel 00, with the microLED array panel 00 arranged at the center of the concave surface, to collect light emitted from one or more portions of the microLED array.

[0047] Reference Figure 24 and Figure 25 The bottom of the second light collector 102 can be located below the micro-LED array panel 00.

[0048] The aforementioned inspection tools can be used in any system for inspecting microLED array panels, such as pixel defect inspection systems, optical inspection systems, etc. Furthermore, the microLED array panel 00 can be a single panel; alternatively, the microLED array panel can be replaced by multiple panels disposed on a wafer. The microLED array panel 00 is supported on a sample stage 04. The sample stage 04 can move in any direction and / or rotate at any angle to align the microLED array panel 00 with the first light collector 101.

[0049] It should be noted that the second light collector 102 can be mounted on the sample stage 04 or at any other location in the inspection system, such as a fixture for mounting the image acquisition unit 02 or the first light collector 101. During operation, the first light collector 101 can be adjusted to an optimized position to obtain a clear image of one or more portions of the microLED array. The inspection process can begin when the microLED array panel 00 is aligned with the first light collector 101 without adjusting the position of the second light collector 102. In other words, the aforementioned position of the second light collector 102 is an optimized position for collecting light emitted from one or more portions of the microLED array.

[0050] The microLED array panel 00 is a miniature self-emissive panel. The LEDs in the panel can be organic or inorganic LEDs. The light-emitting area of ​​the microLED array panel 00 is very small, for example, 3mm × 5mm. It should be noted that the light-emitting area is the area of ​​the microLED array. The microLED array panel includes microLED arrays forming pixel arrays, for example, 1600 × 1200, 680 × 480, or 1920 × 1080. The diameter of the microLEDs is in the range of 200nm to 2μm. However, due to the various optical elements in the first light collector 101, the collection area of ​​the first light collector 101 cannot be as small as the light-emitting area of ​​the microLED array panel 00. If the first light collector 101 is arranged vertically, it will prevent light from directly reaching the second light collector 102. Therefore, the configuration of the first light collector 101 and the second light collector 102 in the embodiments of this disclosure can solve this problem. An IC backplane is formed on the back of the microLED array and is electrically connected to the microLED array. The IC backplane receives signals, such as image data, from the outside via signal lines to control the illumination of the corresponding micro-LEDs. The IC backplane typically employs an 8-bit digital-to-analog converter (DAC). An 8-bit DAC has 256 levels of representation, with each level corresponding to a grayscale level; that is, an 8-bit DAC can provide 256 different grayscale levels. Since any of these 256 grayscale levels can be applied to the micro-LED, grayscale levels in the range of 0 to 255 can be displayed by a single pixel. Optionally, the brightness value of the micro-LED can be controlled by the voltage or current amplitude of the signal received from the IC backplane, while the grayscale level can be displayed by the time interval of the signal, such as the pulse width.

[0051] In this embodiment, the detection area of ​​the first light collector 101 is larger than the light-emitting area of ​​the microLED array. In another embodiment, the detection area of ​​the first light collector 101 may be equal to the light-emitting area of ​​the microLED array.

[0052] Furthermore, according to this embodiment, the detection area of ​​the second light collector 102 is larger than the light-emitting area of ​​the microLED array. In another embodiment, the detection area of ​​the second light collector 102 may be smaller than or equal to the light-emitting area of ​​the microLED array.

[0053] It should be noted that in these embodiments, the first optical collector 101 and the second optical collector 102 are arranged separately. However, in other embodiments, the first optical collector 101 and the second optical collector 102 can be configured together to form a light-collecting area. For example, the first optical collector 101 is in an active state while the second optical collector 102 is in an inactive state. Alternatively, the first optical collector 101 is in an inactive state while the second optical collector 102 is in an active state. Therefore, according to the scope of this disclosure, the optical transmission paths of the first optical collector 101 and the second optical collector 102 can share a single optical transmission path or be different transmission paths.

[0054] The above description is merely an implementation scheme of this disclosure, and this disclosure is not limited thereto. Modifications, equivalent substitutions, and improvements made without departing from the concepts and principles of this disclosure shall fall within the protection scope of this disclosure.

Claims

1. An inspection tool for inspecting micro-LED array panels, characterized in that, include: A light collector group is configured to collect light emitted from a microLED array included in the microLED array panel; An image detector, connected to the light collector group to receive light collected by the light collector group, and configured to capture an image of the microLED array; as well as A light measurement device, electrically connected to the light collector group to receive light collected by the light collector group, and configured to measure light emitted from one or more portions of the microLED array. The light collector group is configured to receive light emitted from any position of the microLED array; The light collector group includes a first light collector and a second light collector, wherein the first light collector is connected to the image detector; the second light collector is electrically connected to the light measurement device; the first light collector is disposed above the microLED array and vertically aligned with the microLED array; and the first light collector is configured to guide light emitted from the microLED array to the image detector. One or more portions of the second light collector have concave surfaces facing the microLED array panel; The second light collector is configured to include at least one or more sides of the first light collector or around the first light collector and above the microLED array panel on the concave surface, and the microLED array panel is arranged at the center of the concave surface for collecting light emitted from one or more portions of the microLED array.

2. The inspection tool for inspecting the microLED array panel according to claim 1, characterized in that, The second light collector is not connected to the first light collector and does not contact the sidewall of the first light collector.

3. The inspection tool for inspecting the microLED array panel according to claim 1, characterized in that, A light transmission channel is configured between the first light collector and the image detector, wherein the second light collector is configured to include at least one or more sides of the light transmission channel or around the light transmission channel and above the microLED array panel, and the microLED array panel is arranged at the center of the concave surface, the concave surface being used to collect light emitted from one or more portions of the microLED array.

4. The inspection tool for inspecting the microLED array panel according to claim 3, characterized in that, The second light collector is not connected to the light transmission channel and does not contact the sidewall of the light transmission channel.

5. The inspection tool for inspecting the microLED array panel according to claim 1, characterized in that, A filter is disposed between the first light collector and the image detector.

6. The inspection tool for inspecting the microLED array panel according to claim 1, characterized in that, The second light collector is configured to include at least one or more sides of the microLED array panel or around the microLED array panel, and the microLED array panel is disposed at the center of the concave surface, the concave surface being used to collect light emitted from one or more portions of the microLED array.

7. The inspection tool for inspecting the microLED array panel according to claim 6, characterized in that, The second light collector is an integrating hemisphere, and the micro-LED array panel is disposed at the center of the hemisphere; wherein, an opening is formed at the top of the hemisphere for inserting the first light collector.

8. The inspection tool for inspecting the microLED array panel according to claim 1, characterized in that, The entire surface of the second light collector is curved.

9. The inspection tool for inspecting the microLED array panel according to claim 1, characterized in that, The detection area of ​​the first light collector is not less than the light-emitting area of ​​the microLED array.

10. The inspection tool for inspecting the microLED array panel according to claim 9, characterized in that, The detection area of ​​the second light collector is larger than the light-emitting area of ​​the microLED array.

11. The inspection tool for inspecting the microLED array panel according to claim 9, characterized in that, The detection area of ​​the second light collector is less than or equal to the light-emitting area of ​​the microLED array.

12. An inspection system for inspecting micro-LED array panels, characterized in that, It includes at least the testing tool as described in claim 1.

13. The inspection system according to claim 12, characterized in that, The light collector group includes a first light collector and a second light collector, wherein the first light collector is connected to the image detector; and the second light collector is connected to the light measurement device; the first light collector is disposed above the microLED array and vertically aligned with the microLED array; and the first light collector is configured to guide light emitted from the microLED array to the image detector.

14. The inspection system according to claim 13, characterized in that, The testing system also includes a sample stage for supporting the microLED array panel.

15. The inspection system according to claim 14, characterized in that, The second light collector is mounted on the sample stage.

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