Touch Sensing Array Substrate for Thin Fingerprint Recognition
Solution Overview
Problem
Existing fingerprint recognition apparatuses are typically too thick to meet market demands for thinner and lighter solutions due to the space occupied by components like prisms, focusing lenses, and image sensors, which hinder their portability and usability.
Innovation Solution
A touch sensing pattern recognition array substrate with a thin film transistor part and a photosensitive part, where the photosensitive layer is sandwiched between opaque and transparent electrodes, allowing for light reflection-based fingerprint recognition without the need for bulky optical components, and a method for fabricating this substrate that includes forming electrodes and layers in single patterning processes to reduce thickness and increase efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional optical components (prisms, focusing lenses, image sensors) are used for fingerprint recognition, then recognition accuracy is maintained, but the apparatus thickness increases
Solution Approach 1:
The patent merges the optical component functions (light reflection, focusing, and sensing) into a single integrated array substrate. The photosensitive layer directly senses reflected light from fingerprints, while the opaque and transparent electrodes provide both structural support and light interaction functions, eliminating the need for separate prisms, lenses, and image sensors.
Solution Approach 2:
The patent extracts and removes the bulky optical components (prisms, focusing lenses, and image sensors) from the traditional fingerprint recognition system, retaining only the essential light sensing function through the photosensitive layer integrated with the array substrate.
2Reliability
If multiple separate components are used for light reflection-based sensing, then sensing function is achieved, but device complexity and thickness increase
Solution Approach 1:
The patent combines multiple functional layers (photosensitive layer, opaque electrode, transparent electrode) into a single integrated sensing unit on the array substrate. This unified structure achieves light reflection-based sensing without requiring separate optical components, thereby reducing device complexity while maintaining sensing reliability.
Solution Approach 2:
The array substrate serves multiple functions simultaneously: it provides structural support, enables light reflection through the transparent electrode, blocks stray light via the opaque electrode, and detects fingerprint patterns through the photosensitive layer. This multi-functionality reduces the need for separate dedicated components.
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 enables a thinner and more portable fingerprint recognition system that effectively identifies fingerprint patterns through light reflection changes, reducing the thickness and weight of the apparatus while maintaining recognition accuracy.
Implementation Method 1
allowing for light reflection-based fingerprint recognition
Implementation Method 2
the photosensitive layer is made of a material selected from one of amorphous silicon and low-temperature polysilicon
Data Source
AI summary
In some embodiments of the disclosed subject matter, a touch sensing pattern recognition array substrate, and related unit, sensor, apparatus, and fabricating method are provided. The sensing unit on the touch sensing pattern recognition array substrate comprises a thin film transistor part and a photosensitive part. The photosensitive part comprises an opaque electrode, a transparent electrode, and a photosensitive layer sandwiched by the opaque electrode and the transparent electrode. The thin film transistor part comprises a gate electrode connected with a scanning line, a source electrode connected with a signal line, and a drain electrode connected with the photosensitive layer of the photosensitive part.