Fingerprint Module Wire Grid Polarizer Thickness Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Fingerprint identification modules integrated into liquid crystal display devices have a high thickness due to multiple structural layers, which complicates the realization of full-screen fingerprint identification functionality.
Innovation Solution
A fingerprint identification module with a first electrode layer and a second electrode layer, where the second electrode layer acts as a wire grid polarizer, reducing the overall thickness by eliminating the need for a separate polarizer and optimizing electrode wire arrangements for efficient capacitance detection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a fingerprint identification module is integrated into a liquid crystal display device with multiple structural layers, then full-screen fingerprint identification function is achieved, but the thickness of the display device increases
Solution Approach 1:
The patent merges the fingerprint identification module with the liquid crystal display device by making the second electrode layer serve dual functions: as electrodes for capacitance detection and as the polarizer for the display. This integration eliminates the need for a separate polarizer layer, thereby reducing overall device thickness while maintaining full-screen fingerprint identification functionality.
Solution Approach 2:
The second electrode layer is designed to perform multiple functions simultaneously: it acts as both the sensing electrodes (first and second electrode wires) for fingerprint detection and as the polarizer for the liquid crystal display. This multi-functionality reduces the number of separate components needed, directly addressing the thickness issue.
2Reliability
If the second electrode layer is designed as a wire grid polarizer with specific wire width and period, then polarization effect is improved, but manufacturing precision requirements increase
Solution Approach 1:
The patent specifies optimized parameter ranges for the wire grid structure: period between 70-200 nm and wire width between 50-150 nm. These parameter ranges are carefully selected to achieve effective polarization while remaining manufacturable with current fabrication capabilities, balancing performance with manufacturing feasibility.
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
Enables full-screen fingerprint identification with reduced thickness, enhancing the display device's structural efficiency and functionality while maintaining accurate fingerprint recognition.
Implementation Method 1
the electrode wires of the upper layer and the lower layer are intersected with each other, and an induction capacitor is formed at each intersection; each induction capacitor is equivalent to a detection pixel, in the case of fingerprint detection, the induction capacitance between the electrode wires of the upper layer and the lower layer is changed due to the introduction of the electric field of a human body
Implementation Method 2
the second electrode layer is a wire grid polarizer
Data Source
AI summary
A fingerprint identification module and a manufacturing method thereof, and a display device are provided. The fingerprint identification module includes: a first electrode layer and a second electrode layer opposed to each other, and a transparent insulating layer interposed between the first electrode layer and the second electrode layer; the first electrode layer includes a plurality of first electrode wires spaced apart from each other; the second electrode layer includes a plurality of second electrode wires spaced apart from each other; the plurality of second electrode wires and the plurality of first electrode wires are intersected with each other; the first electrode layer is formed of a transparent conductive material, and the second electrode layer is a wire grid polarizer.