中文版本

Opportunity  

Organic Light Emitting Diode (OLED) devices are increasingly popular for applications requiring efficient, thin, and flexible lighting solutions. However, a significant challenge persists in achieving uniform luminance across large-area OLED panels. This non-uniformity arises primarily due to the low conductivity of transparent electrode materials (e.g., Indium Tin Oxide or PEDOT:PSS), which leads to inhomogeneous current distribution. As a result, the periphery of the OLED panel often emits brighter light than the center, creating visible hotspots and reducing overall visual quality. This issue becomes more pronounced as the panel size increases or the luminance intensity rises, limiting the practicality of OLEDs in high-performance lighting and display applications. Existing solutions, such as auxiliary metal grids or segmented driving circuits, either compromise transparency or add complexity and cost. Thus, there is a clear need for an innovative approach to enhance luminance uniformity without sacrificing efficiency or simplicity.  

Technology  

This patent introduces a novel method to improve luminance uniformity in OLED panels by strategically controlling heat dissipation patterns. The key innovation lies in manipulating the temperature distribution across the OLED device to counteract the inherent current non-uniformity. The technology operates by:  

1. Differential Heat Dissipation: The method involves dissipating heat in a defined pattern, creating varying temperature zones across the OLED panel. For instance, the center region is maintained at a higher temperature (lower resistance) while the periphery is kept cooler (higher resistance). This compensates for the voltage drop caused by the electrode's resistance, ensuring more uniform current distribution.  
2. Hollow Heat Sink Design: A specially designed hollow heat sink is attached to the cathode, selectively cooling the periphery of the panel. This creates a temperature gradient that mirrors the desired resistance distribution (i.e., "V-shaped" resistance profile), thereby balancing current flow.  
3. Low-Power Operation: The patent also proposes operating the OLED at sub-rated power levels, where the organic semiconductor's resistance is naturally higher, reducing current disparities between the center and edges.  

By integrating these techniques, the patent achieves significantly improved luminance uniformity while maintaining high efficiency and simplicity.  

Advantages  

• Enhanced Luminance Uniformity: Reduces brightness disparities between the center and periphery of OLED panels.  
• Improved Efficiency: Optimizes current distribution, minimizing energy waste in high-resistance areas.  
• Simplified Design: Eliminates the need for complex auxiliary electrodes or segmented driving circuits.  
• Scalability: Effective for large-area OLED panels, addressing a critical limitation in current technology.  
• Flexible Implementation: Compatible with both vertical and horizontal OLED orientations.  

Applications  

• General Lighting: Uniform illumination for residential, commercial, and industrial lighting systems.  
• Displays: High-quality screens for TVs, smartphones, and monitors with consistent brightness.
• Flexible Electronics: Lightweight, bendable lighting solutions for wearable devices and curved displays. 
• Automotive Lighting: Uniform backlighting for dashboards and interior lighting.  
• Decorative Lighting: Aesthetically pleasing, evenly lit panels for architectural and artistic applications.