Inspection tool for inspecting micro LED array panels

Abstract

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

Description

[Technical field]

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

[0002] Micro LED, with its much smaller area and higher resolution, is becoming more and more popular around the world. Micro LED array panels can be used to form various kinds of devices, such as camera modules, light projection modules, display modules, VR / AR optical modules, etc.

[0003] However, pixel defects in the micro LED array panel are not easy to detect and identify by traditional methods since the light emitting area and the image displayed by the micro LED array panel are much smaller than before, which requires operators to scan the wafer, chip, and mask through a graphical user interface that displays various pattern images of the micro LED panel to identify pattern defects.

[0004] In addition, the light-emitting area of ​​the micro LED array panel is extremely small, such as 3mm*5mm. However, the light-collecting area of ​​the optical collector for collecting the light emitted by the micro LED array on the micro LED array panel cannot be as small as the light-emitting area of ​​the micro LED array panel due to various optical components in the optical collector. Therefore, the image collection process and the light collection process cannot be performed simultaneously. Moreover, when the image collection process and the light collection process are performed simultaneously, the light entering the optical collector will be weakened, thereby reducing the image accuracy and measurement accuracy.

[0005] The above contents are only used to help understand the technical solutions of the present application, and are not admitted to be prior art. Summary of the Invention

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

[0007] To achieve the above objectives, the present disclosure provides an inspection tool for detecting a micro LED array panel for increasing the amount of light entering an optical collector.

[0008] An inspection tool for inspecting a micro light emitting diode (LED) array panel according to the present disclosure includes: a collector optics configured to collect light emitted from the micro LED array included in the micro LED array panel; an image detector coupled to the collector optics to receive light collected by the collector optics and configured to capture an image of the micro LED array; a light measurement device electrically connected to the collector group optics to receive light collected by the collector group optics and configured to measure light emitted from one or more portions of the micro LED array; Equipped with Collector optics are configured to receive light emitted from any position of the micro LED array.

[0009] In some embodiments, the optical collector group comprises a first optical collector and a second optical collector, the first optical collector connected to the image detector and the second optical collector electrically connected to the light measurement device, the first optical collector disposed above and vertically aligned with the micro LED array, and the first optical collector configured to direct light emitted from the micro LED array to the image detector.

[0010] In some embodiments, one or more portions of the second collector optics have a concave curved surface facing the micro LED array panel.

[0011] In some embodiments, the second optical collector is configured to at least include a concave curved surface on one or more sides of or around the first optical collector and above the micro LED array panel, and the micro LED array panel is disposed at the center of the concave curved surface, which is used to collect light emitted from one or more portions of the micro LED array.

[0012] In some embodiments, the second collector optics is not connected to the first collector optics and does not contact a sidewall of the first collector optics.

[0013] In some embodiments, an optical transmission channel is configured between the first optical collector and the image detector, and the second optical collector is configured to include at least a concave curved surface on one or more sides of or around the optical transmission channel and above the micro LED array panel, and the micro LED array panel is disposed at the center of the concave curved surface, and the concave curved surface is used to collect light emitted from one or more portions of the micro LED array.

[0014] In some embodiments, the second collector optical is not connected to the optical transmission channel and does not contact a sidewall of the optical transmission channel.

[0015] In some embodiments, a filter is disposed between the first optical collector and the image detector.

[0016] In some embodiments, the second collector optics is configured to at least include a concave curved surface on one or more sides of or around the micro LED array panel, the micro LED array panel being positioned at the center of the concave curved surface, and the concave curved surface is used to collect light emitted from one or more portions of the micro LED array.

[0017] In some embodiments, the second collector optics is an integrating hemisphere, the micro LED array panel is disposed at the center of the hemisphere, and an opening is formed at the apex of the hemisphere for inserting the first collector optics.

[0018] In some embodiments, the entire surface of the second optical collector is curved.

[0019] In some embodiments, the detection area of ​​the first collector optics is equal to or greater than the light emitting area of ​​the microLED array.

[0020] In some embodiments, the detection area of ​​the second collector optics is larger than the light emitting area of ​​the micro LED array.

[0021] In some embodiments, the detection area of ​​the second collector optics is smaller than or equal to the light emitting area of ​​the micro LED array.

[0022] To achieve the above objective, an inspection system for inspecting a micro LED array panel includes at least the inspection tool mentioned above.

[0023] In some embodiments, the optical collector group comprises a first optical collector and a second optical collector, the first optical collector connected to the image detector and the second optical collector connected to the light measurement device, the first optical collector disposed above the micro LED array and vertically aligned with the micro LED array, and the first optical collector configured to direct light emitted from the micro LED array to the image detector.

[0024] In some embodiments, the inspection system further comprises a sample stage for supporting the micro LED array panel.

[0025] In some embodiments, the second optical collector is attached to the sample stage.

[0026] Numerous other advantages and features of the present disclosure will become better understood from the following detailed description and the accompanying drawings. [Brief description of the drawings]

[0027] [Figure 1] FIG. 1 is a block diagram illustrating an inspection tool for inspecting a micro LED array panel according to one embodiment of the present disclosure. [Diagram 2] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Diagram 3] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Figure 4] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Diagram 5] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Figure 6] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Figure 7] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Figure 8] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Figure 9] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Figure 10] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Figure 11] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Figure 12] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Figure 13] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Figure 14] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Figure 15] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Figure 16] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Figure 17] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Figure 18] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Figure 19] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Figure 20] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Figure 21] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Figure 22] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Figure 23] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Figure 24] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. [Diagram 25] 1A-1C are schematic diagrams illustrating configurations of inspection tools according to various embodiments of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] Reference will now be made in detail to preferred embodiments of the invention in order to provide a further understanding of the present disclosure. The specific embodiments discussed and the accompanying drawings are merely illustrative of specific ways to make and use the disclosure and do not limit the scope of the disclosure or the appended claims.

[0029] 1 and 2, an inspection tool for inspecting a micro LED array panel according to an embodiment of the present disclosure includes: a collector optics group 01 configured to collect light emitted from the micro LED array included in the micro LED array panel 00; an image detector 02 coupled to the optical collector group 01 for receiving light collected by the optical collector group 01 and configured to capture an image of the micro LED array; a light measurement device 03 electrically connected to the optical collector group 01 for receiving light collected by the optical collector group and for detecting light emitted from one or more portions of the micro LED array; Equipped with A collector optics group 01 is configured to receive light emitted from any position of the micro LED array.

[0030] Additionally, the image detector 02 may include, but is not limited to, a charge-coupled device detector, a photomultiplier tube detector, etc. The light measurement device 03 may include, but is not limited to, a spectrometer. The light measurement device 03 may measure any optical parameter of the emitted light, such as half-maximum peak width, peak width, etc.

[0031] The optical collector group 01 comprises a first optical collector 101 and a second optical collector 102, the first optical collector 101 is connected to the image detector 02, the second optical collector 102 is electrically connected to the light measurement device 03, the first optical collector 101 is disposed above the micro LED array panel 00 and is vertically aligned with the micro LED array panel 00, and the first optical collector 101 directs light emitted from the micro LED array panel 00 to the image detector 02.

[0032] Moreover, one or more portions of the second optical collector 102 include a concave curved surface facing the micro LED array panel 00. The concave curved surface may have an inwardly concave shape, which is similar to a piece of the edge of a plate or bowl. Preferably, the entire surface of the second optical collector 102 may be curved. Here, the first optical collector 101 includes various optical components for collecting and directing the light emitted from the micro LED array. The optical components may include lenses, mirrors, filters, beam splitters, etc. Referring to FIG. 2, for example, a filter 104 may be disposed in the optical path between the first optical collector 101 and the image detector 02 to filter unexpected light or attenuate the light intensity. It should be noted that the second optical collector 102 may be electrically connected to the light measurement device 03 via a conductive line 06. The conductive line 06 may include an optical fiber. In some embodiments, the second collector optics may include a light focusing device that focuses the light collected by the concave curved surface onto the ends of the conductive lines 06.

[0033] 3 and 4, the second collector optics 102 is configured to at least include a concave curved surface below one or more sides of the first collector optics 101 or around the bottom of the first collector optics 101 and above the micro LED array panel 00, the concave curved surface being used to collect light emitted from one or more portions of the micro LED array. For example, as shown in FIG. 3, a cross-sectional view of an inspection tool according to one embodiment, the second collector optics 102 includes a portion of the concave curved surface below one side of the first collector optics 101. As another example, as shown in FIG. 4, a cross-sectional view of an inspection tool according to another embodiment, the second collector optics 102 includes a full concave curved surface surrounding the bottom of the first collector optics 101. Additionally, the second collector optics 102 is not connected to the first collector optics 101 and does not contact the sidewalls of the first collector optics 101. 5 and 6, the second collector optics 102 may be attached to the stage 04 for supporting the micro LED array panel 00. With reference to Figures 7 and 8, the second collector optics 102 may be attached to the first collector optics 101 for supporting the micro LED array panel 00. Preferably, at least one point or center of the micro LED array panel 00 is located at the center of the concave curved surface.

[0034] 9 and 10, the second collector optics 102 is configured with a concave curved surface on one or more sides or around the micro LED array panel 00, and preferably the micro LED array panel 00 is disposed at the center of the concave curved surface to collect light emitted from one or more portions of the micro LED array. Preferably, the concave curved surface is a hemisphere. It is noted that the bottom of the second collector optics 102 may be below the bottom of the micro LED array panel 00.

[0035] Moreover, referring to Fig. 11, the second collector optics 102 is a sphere. For example, the second collector optics 102 may be an integrating hemisphere, and preferably the micro LED array panel 00 is disposed at the center of the hemisphere, where an opening is formed at the top of the sphere for inserting the first collector optics 101.

[0036] 12 and 13, the second collector optics 102 is configured to have a concave curved surface on one or more sides of or around the first collector optics 101 and above the micro LED array panel 00, the concave curved surface being used to collect light emitted from one or more portions of the micro LED array. Additionally, the second collector optics 102 is not connected with the first collector optics 101 and does not contact the sidewalls of the first collector optics 101. Preferably, the micro LED array panel 00 is disposed at the center of the concave curved surface. Referring to FIGS. 14-17, the second collector optics 102 may be attached to the first collector optics 101 or to a sample stage 04 for supporting the micro LED array panel 00. Preferably, at least one point or center of the micro LED array panel 00 is disposed at the center of the concave curved surface.

[0037] Moreover, referring to FIG. 18 and FIG. 19, the optical transmission channel 103 is configured between the first optical collector 101 and the image detector 02. As shown in FIG. 18 and FIG. 19, the second optical collector 102 is configured to have a concave curved surface on one or more sides of or around the optical transmission channel 103 and above the micro LED array panel 00, preferably the micro LED array panel 00 is disposed at the center of the concave curved surface, and the second optical collector 102 is used to collect light emitted from one or more portions of the micro LED array. Moreover, the second optical collector 102 is not connected with the optical transmission channel 103 and does not contact the sidewalls of the optical transmission channel 103. Referring to FIG. 20-FIG. 23, the second optical collector 102 may be attached to the optical transmission channel 103 or to a sample stage 04 for supporting the micro LED array panel 00. Additionally, the second optical collector 102 may be configured to include a concave curved surface around the optical transmission channel 103 and above the micro LED array panel 00, the micro LED array panel 00 being disposed at the center of the concave curved surface to collect light emitted from one or more portions of the micro LED array.

[0038] With reference to FIGS. 24 and 25, it should be noted that the bottom of the second collector optics 102 may be below the micro LED array panel 00.

[0039] The above mentioned inspection tools may be used for any system to detect the micro LED array panel, such as pixel defect inspection system, optical inspection system, etc. Additionally, the micro LED array panel 00 may be a one piece panel, or the micro LED array panel may be replaced with a panel of more pieces arranged on a wafer. The micro LED array panel 00 is supported on a sample stage 04. The sample stage 04 may move in any direction and / or rotate to any angle to align the micro LED array panel 00 with the first optical collector 101.

[0040] It should be noted that the second collector optics 102 may be attached to any other location of the inspection system, such as the sample stage 04 or a fixture for mounting the imaging collector 02 or the first collector optics 101, etc. During operation, the first collector optics 101 may be adjusted to an optimized position for acquiring one or more portions of a clear image of the micro LED array. When the micro LED array panel 00 is aligned with the first collector optics 101, the inspection process may begin without adjusting the position of the second collector optics 102. That is, the above-mentioned position of the second collector optics 102 is an optimized position for collecting light emitted from one or more ports of the micro LED array.

[0041] The micro LED array panel 00 is a micro self-luminous panel. The LEDs in the panel can be organic LEDs or inorganic LEDs. The light-emitting area of ​​the micro LED array panel 00 is extremely small, such as 3mm*5mm. It should be noted that the light-emitting area is the area of ​​the micro LED array. The micro LED array panel comprises a micro LED array forming a pixel array, such as 1600x1200, 680x480, 1920x1080, etc. The diameter of the micro LED is in the range of 200nm to 2μm. However, the light-collecting area of ​​the first optical collector 101 cannot be as small as the light-emitting area of ​​the micro LED array panel 00 due to various optical components in the first optical collector 101, which prevents the light from directly reaching the second optical collector 102 when the first optical collector 101 is arranged vertically. Thus, the configuration of the first optical collector 101 and the second optical collector 102 in the embodiment of the present disclosure can solve this problem. An IC backplane is formed on the back surface of the micro LED array and electrically connected with the micro LED array. The IC backplane acquires signals such as image data from the outside through signal lines to control corresponding micro LEDs to emit light. The IC backplane generally adopts an 8-bit digital-to-analog converter (DAC). The 8-bit DAC has 256 levels of display, each level corresponds to one gray level, that is, the 8-bit DAC can provide 256 different gray levels. Any one of the 256 gray levels can be applied to the micro LED, so that gray levels ranging from 0 to 255 can be displayed by one pixel. Optionally, the luminance value of the micro LED can be controlled by the voltage amplitude or current amplitude of a signal acquired by the IC backplane, and the gray level can be indicated by the time interval, e.g., pulse width, of the signal.

[0042] In an embodiment, the detection area of ​​the first collector optics 101 is larger than the light emitting area of ​​the micro LED array. In another embodiment, the detection area of ​​the first collector optics 101 may be equal to the light emitting area of ​​the micro LED array.

[0043] Additionally, the detection area of ​​the second collector optics 102 is larger than the light emitting area of ​​the micro LED array in accordance with an embodiment. In another embodiment, the detection area of ​​the second collector optics 102 may be smaller than or equal to the light emitting area of ​​the micro LED array.

[0044] It should be noted that the first collector optics 101 and the second collector optics 102 are disposed separately in the embodiment. However, in another embodiment, the first collector optics 101 and the second collector optics 102 may be configured together to form one light collection area, for example, the first collector optics 101 is in an active state and the second collector optics 102 is in an inactive state, or the first collector optics 101 is in an inactive state and the second collector optics 102 is in an active state. Thus, the optical transmission paths for the first collector optics 101 and the second collector optics 102 may share one optical transmission path or various transmission paths in accordance with the scope of the present disclosure.

[0045] The above description is only the embodiment of the present disclosure, and the present disclosure is not limited thereto. Any modifications, equivalent replacements, and improvements made without departing from the concept and principle of the present disclosure shall be within the protection scope of the present disclosure.

Claims

1. 1. An inspection tool for inspecting a micro light emitting diode (LED) array panel, comprising: a collector optics configured to collect light emitted from a micro LED array included in the micro LED array panel; an image detector coupled to the group of collector optics to receive the light collected by the group of collector optics and configured to capture an image of the micro LED array; a light measurement device electrically connected to the group of collector optics to receive the light collected by the group of collector optics and configured to measure the light emitted from one or more portions of the micro LED array; Equipped with the collector optics are configured to receive the light emitted from any position of the micro LED array; Inspection tool.

2. 2. The inspection tool for inspecting a micro LED array panel of claim 1, wherein the optical collector group comprises a first optical collector and a second optical collector, the first optical collector connected to the image detector and the second optical collector electrically connected to the light measurement device, the first optical collector disposed above and vertically aligned with the micro LED array, and the first optical collector configured to direct the light emitted from the micro LED array to the image detector.

3. 3. The inspection tool for inspecting a micro LED array panel of claim 2, wherein one or more portions of the second optical collector have a concave curved surface facing the micro LED array panel.

4. 4. An inspection tool for inspecting a micro LED array panel as claimed in claim 3, wherein the second optical collector is configured to at least comprise the concave curved surface on one or more sides of or around the first optical collector and above the micro LED array panel, the micro LED array panel being positioned at the centre of the concave curved surface, and the concave curved surface is used to collect the light emitted from one or more portions of the micro LED array.

5. 5. The inspection tool for inspecting a micro LED array panel of claim 4, wherein the second collector optics is not connected to the first collector optics and does not contact a sidewall of the first collector optics.

6. 4. An inspection tool for inspecting a micro LED array panel according to claim 3, wherein an optical transmission channel is configured between the first optical collector and the image detector, the second optical collector is configured to at least comprise the concave curved surface on one or more sides of or around the optical transmission channel and above the micro LED array panel, the micro LED array panel is positioned at the center of the concave curved surface, and the concave curved surface is used to collect the light emitted from one or more portions of the micro LED array.

7. 8. The inspection tool for inspecting a micro LED array panel of claim 7, wherein the second optical collector is not connected with and does not contact a sidewall of the optical transmission channel.

8. 3. The inspection tool for inspecting a micro LED array panel of claim 2, wherein a filter is disposed between the first optical collector and the image detector.

9. 4. An inspection tool for inspecting a micro LED array panel according to claim 3, wherein the second optical collector is configured to at least comprise the concave curved surface on one or more sides of or around the micro LED array panel, the micro LED array panel being centered on the concave curved surface, and the concave curved surface is used to collect the light emitted from one or more portions of the micro LED array.

10. 10. The inspection tool for inspecting a micro LED array panel of claim 9, wherein the second collector optical element is an integrating hemisphere, the micro LED array panel is disposed at the center of the hemisphere, and an opening is formed at the apex of the hemisphere for inserting the first collector optical element.

11. 4. The inspection tool for inspecting a micro LED array panel of claim 3, wherein an entire surface of the second collector optics is curved.

12. 4. The inspection tool for inspecting a micro LED array panel of claim 3, wherein a detection area of ​​the first optical collector is equal to or greater than a light emitting area of ​​the micro LED array.

13. 13. The inspection tool for inspecting a micro LED array panel of claim 12, wherein a detection area of ​​the second collector optical is larger than the light emitting area of ​​the micro LED array.

14. 13. The inspection tool for inspecting a micro LED array panel of claim 12, wherein a detection area of ​​the second collector optical is less than or equal to the light emitting area of ​​the micro LED array.

15. 13. An inspection system for inspecting a micro LED array panel comprising at least the inspection tool of claim 1.

16. 16. The inspection system of claim 15, wherein an optical collector group comprises a first optical collector and a second optical collector, the first optical collector connected to an image detector and the second optical collector connected to the light measurement device, the first optical collector disposed above and vertically aligned with the micro LED array, and the first optical collector configured to direct the light emitted from the micro LED array to the image detector.

17. 20. The inspection system of claim 16, wherein the inspection system further comprises a sample stage for supporting the micro LED array panel.

18. The inspection system of claim 17 , wherein the second optical collector is attached to the specimen stage.

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