Ultrasonic Fingerprint Sensor Integrated in Display Substrate
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current ultrasonic fingerprint recognition modules for smartphones are costly and complex due to their external attachment to the display, increasing manufacturing costs and labor, and they cannot effectively recognize fingerprints through glass, stainless steel, sapphire, or plastic cases, nor can they differentiate through sweat, oil, and dirt.
Innovation Solution
Integrating an ultrasonic fingerprint recognition sensor within the display substrate, where the generator and receiver can be positioned in different or the same inter-pixel portions, utilizing piezoelectric materials and electrodes to form a compact and efficient recognition system that does not interfere with the display functionality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If ultrasonic fingerprint recognition module is externally attached to display, then fingerprint recognition function is achieved, but manufacturing cost and device complexity increase
Solution Approach 1:
The patent merges the ultrasonic fingerprint recognition module with the display substrate by integrating the generator and receiver directly into the display structure. The generator is formed in an inter-pixel portion of the pixel definition layer, and the receiver is positioned in close proximity, eliminating the need for separate external modules and reducing overall device complexity while maintaining fingerprint recognition functionality.
Solution Approach 2:
The display substrate is designed to serve multiple functions: it acts as both the display structure and the fingerprint recognition platform. The inter-pixel portions of the pixel definition layer are utilized to house the fingerprint sensor components, allowing the display substrate to simultaneously perform display and biometric authentication functions without requiring additional dedicated structures.
2Reliability
If ultrasonic fingerprint recognition module is externally attached to display, then fingerprint recognition function is achieved, but manufacturing cost and labor increase
Solution Approach 1:
The manufacturing process merges the formation of the display substrate and fingerprint sensor into a single integrated process. The generator is formed using the same pixel definition layer formation steps, and the receiver is positioned during the same manufacturing sequence, eliminating the need for separate assembly steps and reducing labor costs while ensuring functional integration.
Solution Approach 2:
The fingerprint sensor components (generator and receiver) are preliminarily positioned and integrated into the display substrate during the display manufacturing process itself, before final assembly. This preliminary integration ensures that the fingerprint recognition function is built-in from the start, avoiding costly post-assembly operations and simplifying the overall manufacturing workflow.
3Measurement precision
If external ultrasonic fingerprint sensor is used, then basic recognition is possible, but recognition through glass, stainless steel, sapphire, or plastic cases fails
Solution Approach 1:
The patent uses the display substrate itself as an intermediary medium between the ultrasonic sensor and the fingerprint. The generator and receiver are integrated within the display structure, allowing ultrasonic waves to travel through the display substrate materials (glass, plastic, etc.) to reach and detect the fingerprint, thereby enabling recognition through various case materials that would block external sensors.
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 integration simplifies manufacturing, reduces costs, and enhances fingerprint recognition accuracy by scanning through various materials and surface conditions, providing stable and detailed fingerprint authentication.
Implementation Method 1
the generator includes a first lower electrode, a first piezoelectric material, and a first upper electrode which are sequentially stacked in a direction away from the substrate
Implementation Method 2
the receiver includes a second lower electrode, a second piezoelectric material, and a second upper electrode which are sequentially stacked in a direction away from the substrate
Data Source
AI summary
Embodiments of the present disclosure relate to a display substrate, a method for manufacturing the same, and a display device. The display substrate includes a substrate, a pixel definition layer for defining pixels on the substrate, the pixel definition layer including a plurality of inter-pixel portions located between adjacent pixels, and a fingerprint recognition sensor located in the inter-pixel portions.