Display Pixel-Group Current Mirroring for Gray Scale Accuracy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing display devices face challenges in maintaining consistent current levels across multiple pixels due to resistance issues caused by common voltages, leading to variations in gray scale and increased power consumption.
Innovation Solution
The display device employs a reference current source connected to a pixel array through sub-current sources and pixel circuits, utilizing current mirroring and additional elements to minimize resistance and voltage requirements, ensuring consistent current distribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a current source is used to control light emission of multiple pixels, then light emission control is achieved, but resistance caused by common voltages leads to current variation and gray scale errors
Solution Approach 1:
The patent divides the pixel array into multiple pixel groups, with each group having its own sub-current source. This segmentation isolates the current control paths, reducing the impact of common voltage resistance on individual pixels and improving current consistency across the display.
Solution Approach 2:
The patent introduces additional transistors and resistors as intermediary elements in the current mirror circuit. These intermediary components compensate for voltage drops caused by common resistance, ensuring more accurate current mirroring and reducing gray scale errors.
2Measurement precision
If additional elements are added to reduce resistance influence, then current accuracy improves, but device complexity increases
Solution Approach 1:
By segmenting the display into pixel groups rather than treating all pixels uniformly, the patent reduces the scale of compensation needed in each segment. This allows the use of additional elements only where necessary, balancing accuracy improvement with manageable complexity.
Solution Approach 2:
The patent applies additional compensation elements (transistors and resistors) locally within pixel groups that require them, rather than uniformly across the entire display. This localized approach improves current accuracy where needed while minimizing overall circuit complexity.
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
This approach reduces errors in current provision, minimizes voltage drops, and lowers power consumption by grouping pixels and using additional elements to mirror reference currents effectively.
Implementation Method 1
provides a first mirroring current obtained by mirroring the reference current
Implementation Method 2
provides a second mirroring current obtained by mirroring the first mirroring current
Implementation Method 3
control the light emission of each of a plurality of pixels
Data Source
AI summary
A display device is proposed. The device may include a pixel array including n pixel groups, a reference current source including a first reference transistor through which a reference current flows and connected to the pixel array, and n sub-current sources each included in the n pixel groups and each including a first transistor connected to the reference current source, and n pixel circuits connected to the n sub-current sources, respectively. The reference current source may include any one of a second reference transistor and a reference resistor connected to the first reference transistor. Each of the n sub-current sources may provide a first mirroring current, and each of the n pixel circuits may provide a second mirroring current obtained by mirroring the first mirroring current. Each of the n sub-current sources may include any one of an additional transistor and an additional resistor connected to the first transistor.