In-Display Fingerprint Module with Stacked Electrodes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current fingerprint identification modules in display devices compromise screen-to-body ratio and identification accuracy due to their placement outside the display region, and increasing electrode size to improve penetration ability decreases resolution and accuracy.
Innovation Solution
A fingerprint identification layer with a special structure is integrated into the display panel, featuring sequentially stacked insulating and conductive layers, including multifunctional electrodes and driving/sensing electrodes connected in specific configurations to enhance capacitance sensing without expanding the electrode size, thereby improving penetration ability and accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the fingerprint identification module is placed in non-display regions, then the penetration ability is improved, but the screen-to-body ratio is reduced and internal space is occupied
Solution Approach 1:
The patent merges the fingerprint identification module with the display region by integrating the fingerprint identification electrode into the display panel structure. The electrode is positioned in the display region and electrically connected to the fingerprint identification circuit, allowing the module to function within the display area rather than occupying separate non-display regions.
Solution Approach 2:
The display panel serves multiple functions: it acts as both the display interface and the fingerprint identification interface. The fingerprint identification electrode is integrated into the display panel layers, enabling the display region to simultaneously perform display and biometric authentication functions.
2Reliability
If the size of the fingerprint identification electrode is increased, then the penetration ability is improved, but the resolution and identification accuracy decrease
Solution Approach 1:
The patent applies different patterns and densities of fingerprint identification electrodes in different regions of the display panel. The electrode configuration is optimized locally to achieve uniform capacitance distribution across the fingerprint recognition area, ensuring both sufficient penetration ability and high identification accuracy through localized electrode design adjustments.
Solution Approach 2:
The patent optimizes the parameters of the fingerprint identification electrode including its size, shape, spacing, and material composition. By carefully controlling these parameters, the electrode achieves optimal capacitance values that provide sufficient penetration ability while maintaining high resolution and identification accuracy.
3Area of stationary object
If the fingerprint identification module is integrated into the display region, then the screen-to-body ratio is maximized, but the penetration ability and identification accuracy are compromised
Solution Approach 1:
The patent utilizes the vertical dimension by stacking multiple conductive layers (first conductive layer, second conductive layer, third conductive layer) to create a three-dimensional electrode structure. This multi-layer configuration increases the effective electrode area and capacitance sensing capability without expanding the horizontal footprint, thereby maintaining high screen-to-body ratio while achieving sufficient penetration ability.
Solution Approach 2:
The patent employs composite material structures for the fingerprint identification electrode, combining different conductive materials with appropriate insulating layers. This composite structure optimizes both the electrical properties (for penetration ability) and the spatial efficiency (for screen-to-body ratio) of the integrated fingerprint module.
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 increases the overall capacitance sensing amount while maintaining identification accuracy, enhancing the fingerprint identification module's penetration ability and accuracy within the display region without increasing the electrode size.
Implementation Method 1
capacitive sensor utilizes the conductive properties of human skin to detect fingerprint patterns
Data Source
AI summary
The present invention discloses a display module and a display device. The display module includes a display panel and a fingerprint identification layer. The fingerprint identification layer includes a first conductive layer including a multifunctional electrode, a second conductive layer including a first driving electrode, a sensing electrode, and a second driving electrode. The first driving electrode and the second driving electrode are both electrically connected to the multifunctional electrode. The sensing electrode is insulated from the multifunctional electrode. Orthographic projections of the sensing electrode and the multifunctional electrode on the display panel have an overlapping region.