Organic Electro-Luminescent Display Luminance Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Organic electro-luminescent displays face challenges in controlling power consumption and contrast due to high electric current requirements, leading to increased production costs and potential driving interruptions.
Innovation Solution
An organic electro-luminescent display system that limits power consumption by using a look-up table to control the total brightness of images based on grey levels, with a power supply unit providing two currents and a luminance control unit managing pulse widths of light emission control signals to optimize contrast and reduce power usage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If a large electric current is applied to achieve high total brightness, then the luminance of the display is improved, but the contrast is reduced due to smaller apparent difference in brightness between grey levels
Solution Approach 1:
The patent applies parameter changes by dynamically adjusting the light emission control signal parameters (pulse width, duty cycle) based on the sum of grey levels. When the total grey level sum exceeds a threshold, the system reduces the light emission control signal parameters to maintain contrast, thereby resolving the contradiction between total brightness and contrast preservation.
2Manufacturing precision
If a power supply unit that produces a large flow of high voltage electric current is used to solve contrast issues, then the contrast is improved, but the production cost increases
Solution Approach 1:
The patent replaces the mechanical/power-intensive solution (high voltage power supply unit) with a control-based solution (luminance control unit adjusting light emission control signals). This substitution maintains contrast improvement while avoiding the increased production costs associated with high-voltage power supply components.
3Manufacturing precision
If a power supply unit that produces a large flow of high voltage electric current is used to improve contrast, then the contrast is improved, but the system becomes more complex and may cause driving interruptions
Solution Approach 1:
The patent replaces the complex high-voltage power supply unit with a simpler luminance control unit that operates within the existing power supply framework. This control-based approach achieves contrast improvement without adding the complexity and reliability risks associated with high-voltage power supply systems.
4Use of energy by moving object
If the electric current is limited to reduce power consumption, then the power consumption is reduced, but the total brightness decreases
Solution Approach 1:
The patent applies dynamics by making the light emission control signal parameters adaptive rather than fixed. The luminance control unit dynamically adjusts the pulse width and duty cycle of the light emission control signal based on the sum of grey levels, enabling the system to optimize between power consumption and total brightness in real-time according to display conditions.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system effectively reduces power consumption and enhances contrast by limiting electric current flow, preventing high power loading and improving image visibility by maintaining a greater difference in grey levels.
Implementation Method 1
An organic light emitting diode emits light by coupling electrons with holes
Data Source
AI summary
An organic electro-luminescent display and a making method of the same. The organic electro-luminescent display according to the present invention includes a luminance control unit including a data sum-up unit to generate a frame data; a look-up table for storing an information corresponding to the light emission control signal to correspond to the frame data; an operator unit to generate a look-up table by using a value at the beginning step of luminance reduction, a value at the final step of luminance reduction, a pulse width of the light emission control signal at the beginning step of luminance reduction, and a pulse width of the light emission control signal at the final step of luminance reduction; and a luminance control signal driver for outputting a luminance control signal using the information corresponding to the light emission control signal stored in the look-up table.