Pixel Circuit for Simultaneous Subpixel Driving

Solution Overview

Problem

Time division driving methods in display devices can impair image quality by dividing the screen into multiple frames, making the pattern observable to the user and deteriorating picture quality.

Innovation Solution

A pixel configuration with multiple transistors and capacitors, including switching, compensation, and driving transistors, along with specific scan signals and initialization transistors, allows for simultaneous control of driving currents to two subpixels, enabling light emission without dividing the frame into subfields.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If time division driving method is used to drive multiple subpixels, then the driving circuit can control multiple subpixels with one circuit, but the screen is divided into multiple frames which impairs image quality

Engineering Contradiction:

Improvedriving circuit complexityVSAvoidimage quality

Core Design Contradiction:

Device complexityVSManufacturing precision

Solution Approach 1:

The pixel circuit is segmented into multiple independent driving transistors (first driving transistor for first subpixel, second driving transistor for second subpixel), each capable of independent operation. This segmentation allows simultaneous driving of multiple subpixels without time division, eliminating the frame division problem while maintaining circuit efficiency

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent transitions from temporal dimension (time division driving) to spatial dimension (parallel driving within same frame). By adding multiple driving transistors in parallel within the pixel circuit, both subpixels can be driven simultaneously in the same frame period, moving from sequential time-based control to parallel space-based control

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Use of energy by moving object

If time division driving is implemented, then power consumption can be reduced by activating subpixels sequentially, but the visibility of subfield divisions deteriorates picture quality

Engineering Contradiction:

Improvepower consumptionVSAvoidpicture quality

Core Design Contradiction:

Use of energy by moving objectVSManufacturing precision

Solution Approach 1:

The pixel circuit is segmented into multiple independent driving transistors (first driving transistor for first subpixel, second driving transistor for second subpixel), each capable of independent operation. This segmentation allows simultaneous driving of multiple subpixels without time division, eliminating the frame division problem while maintaining circuit efficiency

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent transitions from temporal dimension (time division driving) to spatial dimension (parallel driving within same frame). By adding multiple driving transistors in parallel within the pixel circuit, both subpixels can be driven simultaneously in the same frame period, moving from sequential time-based control to parallel space-based control

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Data Source

PatentUS9552765B2Pixel, pixel driving method, and display device including the pixel

Publication Date: 2017.01.24 SAMSUNG DISPLAY CO LTD

AI summary

A pixel includes a switching transistor connected to a data line, a first circuit to control compensation of a first driving transistor, and a second circuit to control compensation of a second driving transistor. The first and second circuits are connected to the switching transistor. The first and second transistors are connected to respective organic light emitting diodes of a same pixel. Compensation of the first and second driving transistors is based on respective first and second subscan signals, which overlap periods of corresponding common scan signals to be received by the switching transistor.