Micro-LED Electrode Pad Thickness for Color Uniformity and Ghosting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Display devices using semiconductor light emitting diodes exhibit asymmetrical light distribution due to crystallinity, leading to color variations when viewed from different directions and potential ghost phenomena from parasitic capacitance issues.
Innovation Solution
The use of a wiring substrate with electrode pads of varying thicknesses to compensate for the tilt angle of light emitting devices, ensuring symmetrical light distribution and reducing parasitic capacitance by aligning the thickness difference with the tilt angle of the light emitting devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If light emitting devices are mounted on a wiring substrate with standard electrode pads, then the devices can be electrically connected and functionally operational, but the asymmetrical light distribution caused by crystallinity results in color variations when viewed from different directions
Solution Approach 1:
The patent applies asymmetry by designing electrode pads with different thicknesses to match the asymmetrical tilt angle of light emitting devices. Specifically, the first electrode pad has a first thickness and the second electrode pad has a second thickness that is different from the first thickness, creating an asymmetrical structure that compensates for the device tilt and achieves symmetrical light distribution.
2Ease of manufacture
If light emitting devices with tilted crystal surfaces are used, then the devices can be manufactured using standard sapphire substrates, but the tilt angle creates asymmetrical light distribution and viewing angle dependence
Solution Approach 1:
The patent uses asymmetry by creating electrode pads with different thicknesses that correspond to the tilt angle of the light emitting devices. The first electrode pad has a first thickness and the second electrode pad has a second thickness, forming an asymmetrical structure that compensates for the device tilt and achieves symmetrical light distribution.
Solution Approach 2:
The patent applies parameter changes by modifying the thickness parameter of the electrode pads to compensate for the tilt angle. The different thicknesses of the first and second electrode pads create a geometric compensation that adjusts the light distribution symmetry without changing the light emitting device structure itself.
3Device complexity
If standard thickness electrode pads are used, then the wiring substrate structure is simple and easy to manufacture, but parasitic capacitance occurs due to electric field differences, causing ghost phenomena
Solution Approach 1:
The patent applies asymmetry by designing electrode pads with different thicknesses to match the asymmetrical tilt angle of light emitting devices. Specifically, the first electrode pad has a first thickness and the second electrode pad has a second thickness that is different from the first thickness, creating an asymmetrical structure that compensates for the device tilt and achieves symmetrical light distribution.
Data Source
AI summary
The present disclosure is applicable to a display device-related technical field and relates to, for example, a display device using a micro light-emitting diode (LED). The present disclosure as such comprises: a wiring board on which a plurality of unit pixel regions are defined; a wiring electrode arranged on the wiring board, the wiring electrode comprising a first wiring electrode and a second wiring electrode; and a light-emitting element that forms a sub-pixel by being installed to be electrically connected to the first wiring electrode and the second wiring electrode in each of the unit pixel regions, wherein the light-emitting element may be configured to comprise: a first light-emitting element located in a first pixel region and installed in a first arrangement; and a second light-emitting element located in a second pixel region neighboring the first pixel region and installed in a second arrangement that is symmetrical to the first arrangement.