Semiconductor Resistance Elements for Force Detection in Display Devices
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional touch detection systems for display devices face challenges in accurately detecting force applied to the display face while maintaining cost-effectiveness, often requiring additional components and processes that increase costs and complexity.
Innovation Solution
A display device configuration that includes a first and second substrate with spacers, where the first substrate has a display region with pixels, gate lines, signal lines, and semiconductor resistance elements, and a detection circuit that uses a Wheatstone bridge circuit to detect force based on midpoint voltage between overlapping and non-overlapping semiconductor resistance elements, maintaining equivalent resistance values when no force is applied.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If a direct backlight unit is used between the electrode for detection and the reference potential layer, then the distance between them increases, but capacitance is reduced which causes detection failure
Solution Approach 1:
The invention merges the force detection function with the existing pixel transistor semiconductor layer by forming semiconductor resistance elements directly in the semiconductor layer. This integration eliminates the need for separate detection electrodes and reference potential layers, thereby avoiding the capacitance reduction problem caused by increased distance from backlight units while maintaining accurate force detection capability.
2Reliability
If an electrode for force detection is provided outside the display panel, then force detection is enabled, but cost increases due to additional processes
Solution Approach 1:
The invention makes the semiconductor layer serve multiple functions: it acts as both the active component of pixel transistors and the sensing element for force detection through the semiconductor resistance elements. This multi-functionality eliminates the need for separate detection electrodes and additional manufacturing processes, thereby reducing costs while maintaining force detection capability.
Solution Approach 2:
The semiconductor layer itself serves the detection function by forming resistance elements that change resistance based on applied force. The existing semiconductor material and structure are utilized for dual purposes (transistor operation and force sensing), eliminating the need for external detection components and reducing overall system complexity and cost.
3Ease of manufacture
If semiconductor resistance elements are formed in the same layer as pixel transistors, then cost is reduced by eliminating additional components, but detection accuracy must be maintained
Solution Approach 1:
The invention applies local quality by creating semiconductor resistance elements with specific structural characteristics (overlapping with spacers) in particular regions of the semiconductor layer, while maintaining the transistor functionality in other regions. This localized differentiation allows accurate force detection through resistance changes in specific areas without compromising the overall transistor operation or requiring additional layers.
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 configuration enables precise and cost-effective force detection on the display face by utilizing existing substrate components, reducing the need for additional components and processes, thereby enhancing detection accuracy and reducing costs.
Implementation Method 1
a detection circuit detecting a force applied to the display region based on a midpoint voltage between the first semiconductor resistance element and the second semiconductor resistance element, and a resistance value of the second semiconductor resistance element is equivalent to a resistance value of the first semiconductor resistance element when no force is applied
Data Source
AI summary
Included are at least one first semiconductor resistance element overlapping with one of the spacers and provided as the same layer as the semiconductor layer of the pixel transistors, at least one second semiconductor resistance element provided as the same layer as the semiconductor layer of the pixel transistors and not overlapping with any of the spacers, and a detection circuit detecting a force applied to the display region based on a midpoint voltage between the first semiconductor resistance element and the second semiconductor resistance element, and a resistance value of the second semiconductor resistance element is equivalent to a resistance value of the first semiconductor resistance element when no force is applied.