Double Gate Photo Sensor Pixel for In-Cell Display Integration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In in-cell type display panels, the integration of touch and photo sensor circuits increases the panel defect rate and decreases the aperture ratio and resolution due to higher circuit complexity.
Innovation Solution
A photo sensor pixel with a double gate structure is introduced, comprising a switching transistor and a photo sensing transistor connected in series, where the switching transistor has a top and bottom gate electrode connected to different gate lines, allowing for high sensitivity and reduced area occupation, thereby maintaining aperture ratio and resolution without increasing circuit integration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If touch sensor circuit and photo sensor circuit are integrated in in-cell type display panel, then touch recognition function is enhanced, but panel defect rate increases and aperture ratio decreases
Solution Approach 1:
The photo sensor pixel is segmented into distinct functional regions: a pixel circuit region containing a driving transistor, and a photo sensor circuit region containing a switching transistor and photo sensing transistor. This segmentation allows independent optimization of each region, reducing overall circuit complexity and defect rate while maintaining integrated functionality.
Solution Approach 2:
The patent utilizes vertical stacking to arrange circuit elements in multiple layers above the substrate. The pixel circuit and photo sensor circuit are positioned at different vertical levels, enabling three-dimensional integration that reduces horizontal area occupation and maintains high aperture ratio while achieving circuit integration.
2Adaptability or versatility
If circuit integration is increased in in-cell type display panel, then touch sensor functionality is achieved, but aperture ratio and resolution decrease
Solution Approach 1:
Circuit elements are arranged vertically in multiple layers above the substrate rather than horizontally. The pixel circuit and photo sensor circuit occupy different vertical levels, enabling compact integration that minimizes horizontal area consumption and preserves high aperture ratio for light transmission.
Solution Approach 2:
The patent employs thin-film transistor structures with multiple gate electrodes arranged in vertical stacks. This thin-film approach allows high-density circuit integration in the vertical dimension while maintaining a sleek, minimal horizontal profile that preserves display aperture area.
3Measurement precision
If switching transistor uses double gate structure with top and bottom gate electrodes, then sensitivity and area efficiency are improved, but device complexity increases
Solution Approach 1:
The double gate structure of the switching transistor serves multiple functions simultaneously: the top gate electrode controls switching operation while the bottom gate electrode enhances photo sensing sensitivity. This multi-functional design achieves high sensitivity and area efficiency without requiring separate dedicated structures for each function.
Solution Approach 2:
The switching transistor integrates both switching control and photo sensing capabilities within a single device structure. The top and bottom gate electrodes are combined in a vertical stack, merging control and sensing functions into one compact element that reduces overall device complexity compared to separate components.
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 solution enables effective touch recognition, fingerprint, and vein recognition while minimizing the area occupied by photo sensor pixels, reducing manufacturing costs and maintaining sufficient aperture ratio and resolution in in-cell type display panels.
Implementation Method 1
a photo sensing transistor connected in series with the switching transistor, where the photo sensing transistor senses incident light
Data Source
AI summary
A photo sensor pixel includes a pixel circuit including a driving transistor, a switching transistor having a double gate structure and a photo sensing transistor connected in series with the switching transistor. The pixel circuit drives a light emitting element therein based on a data voltage provided thereto through a data line, the switching transistor includes a top gate electrode and a bottom gate electrode, which are connected to different gate lines, respectively, and the photo sensing transistor senses incident light.