Touch Electrode Phase Driving for Thinner In-Display Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing display devices with touch sensing capabilities require separate sensor layers or digitizer layers, which increase thickness and cost, and do not efficiently sense touch inputs without these additional components.
Innovation Solution
A display device with a touch sensing unit that uses a plurality of touch electrodes disposed on the display unit, and a touch driver that supplies touch driving signals to these electrodes to sense touch inputs without the need for separate sensor layers or digitizer layers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If separate sensor layers or digitizer layers are used for touch sensing, then touch sensing capability is achieved, but device thickness and manufacturing cost increase
Solution Approach 1:
The patent combines the touch sensing function with the existing display electrode structure by using the same electrode patterns for both display driving and touch sensing purposes. The first and second electrodes that form capacitors for display operation also serve as touch sensing electrodes, eliminating the need for separate sensor layers and reducing overall device thickness.
Solution Approach 2:
The electrode structure performs multiple functions: it serves as both the display driving electrode and the touch sensing electrode. The same physical electrodes are used for displaying images and for detecting touch inputs, making the system more compact by eliminating dedicated touch sensing components.
2Reliability
If separate sensor layers or digitizer layers are used for touch sensing, then touch sensing capability is achieved, but manufacturing cost increases
Solution Approach 1:
The patent merges the touch sensing layer with the display electrode layer, so that the same electrode patterns and manufacturing processes are used for both display and touch functions. This consolidation reduces the number of manufacturing steps, materials required, and assembly operations, thereby lowering overall manufacturing cost.
Solution Approach 2:
By designing electrodes that serve dual purposes as both display and touch sensing components, the patent eliminates the need for separate manufacturing lines and material procurement for touch layers, simplifying the supply chain and reducing production costs.
3Measurement precision
If opposite phase driving signals are supplied to first and second electrodes, then touch sensing precision is improved, but signal processing complexity increases
Solution Approach 1:
The patent applies periodic alternating phase signals to the first and second electrodes in a systematic sequence. During a first period, the first electrode receives a driving signal while the second electrode receives an opposite phase signal; during a second period, the roles are reversed. This periodic alternation creates measurable capacitance changes that improve touch detection precision while maintaining manageable signal processing through regular timing patterns.
Solution Approach 2:
The system measures capacitance changes between the electrodes during the alternating phase periods and uses this feedback information to detect touch inputs. The controller monitors the capacitance variations that occur when opposite phase signals are applied and adjusts its detection algorithm based on these measurements, improving precision through adaptive signal processing.
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
The solution allows for efficient touch sensing by generating a magnetic field for charging and discharging a touch input member, reducing the thickness and cost of the display device while maintaining effective touch input detection.
Implementation Method 1
A touch driver configured to supply a touch driving signal to the plurality of touch electrodes and receive a touch sensing signal from the plurality of touch electrodes. The touch driver supplies a first touch driving signal having a first phase to one or more first touch electrodes, and supplies a second touch driving signal having a second phase opposite to the first phase to one or more second touch electrodes
Data Source
AI summary
A display device includes a display unit having pixels, a touch sensing unit including touch electrodes disposed on the display unit, and a touch driver configured to supply a touch driving signal to the plurality of touch electrodes and receive a touch sensing signal from the touch electrodes. The touch driver supplies a first touch driving signal having a first phase to one or more first touch electrodes, and supplies a second touch driving signal having a second phase opposite to the first phase to one or more second touch electrodes, at least a part of which is disposed across a specific point from the first touch electrodes. The touch driver receives a first touch sensing signal having the first phase from at least one of the first touch electrodes, and receives a second touch sensing signal having the second phase from at least one of the second touch electrodes.