Mixing Type Pixel Driving Method for AMOLED Layout Area Reduction

Solution Overview

Problem

Conventional active display devices, such as AMOLEDs, face increased layout area and consumption current due to the analog type driving method, which requires multiple bit digital to analog conversion (DAC) as the bit number of digital data increases, leading to inefficiencies in pixel illumination control.

Innovation Solution

The proposed method involves a 'mixing type pixel driving method' that uses a mapping table to determine variable illumination intensities and intervals within a unit frame period, allowing for independent control of illumination intervals regardless of digital data, reducing the need for high-bit DAC and minimizing layout area and consumption current.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If the bit number of digital data is increased to improve illumination control precision, then the number of intensity levels is increased, but the layout area for DAC and consumption current are increased

Engineering Contradiction:

Improveillumination control precisionVSAvoidlayout area for DAC

Core Design Contradiction:

Measurement precisionVSArea of stationary object

Solution Approach 1:

The patent segments the digital data into two parts: a first digital data determining illumination interval and a second digital data determining illumination intensity. This segmentation allows the system to achieve fine illumination control without requiring high-bit DAC for the entire control signal, thereby reducing layout area while maintaining precision.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent introduces a time dimension by dividing the illumination control into different time intervals. Instead of controlling illumination intensity alone through high-bit digital data, the system controls both the interval duration and the intensity level, effectively using temporal segmentation to reduce the bit requirement for intensity control.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Measurement precision

If the bit number of digital data is increased to improve illumination control precision, then the number of intensity levels is increased, but the consumption current for DAC is increased

Engineering Contradiction:

Improveillumination control precisionVSAvoidconsumption current for DAC

Core Design Contradiction:

Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent segments the digital data into two parts: a first digital data determining illumination interval and a second digital data determining illumination intensity. This segmentation allows the system to achieve fine illumination control without requiring high-bit DAC for the entire control signal, thereby reducing consumption current while maintaining precision.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent introduces a time dimension by dividing the illumination control into different time intervals. Instead of controlling illumination intensity alone through high-bit digital data, the system controls both the interval duration and the intensity level, effectively using temporal segmentation to reduce the bit requirement for intensity control and associated power consumption.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

3Measurement precision

If the number of converted bits for DAC is increased to improve illumination control, then the layout area is increased, but the device complexity is increased

Engineering Contradiction:

Improveillumination control precisionVSAvoiddevice complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent segments the digital data into two parts: a first digital data determining illumination interval and a second digital data determining illumination intensity. This segmentation allows the system to achieve fine illumination control without requiring high-bit DAC for the entire control signal, thereby reducing device complexity while maintaining precision.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent introduces a time dimension by dividing the illumination control into different time intervals. Instead of controlling illumination intensity alone through high-bit digital data, the system controls both the interval duration and the intensity level, effectively using temporal segmentation to reduce the bit requirement for intensity control and associated device complexity.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Data Source

PatentUS8044979B2Active display device and mixing type pixel driving method in active display device

Publication Date: 2011.10.25 TLI

AI summary

A mixing type pixel driving method in an active display device includes generating a digital data for a selected pixel, first driving the selected pixel to be illuminated with a first illumination intensity, and second driving the selected pixel to be illuminated with a second illumination intensity in a second illumination interval. A relative ratio of the second illumination intensity to the first illumination intensity is changed according to the value of the digital data. The number of the converted bits by DAC is reduced. Therefore, the less bit DAC is adaptable for the mixing type pixel driving method and the layout area and the consumption current can be decreased.