Fingerprint Controller Timing Synchronization for Touchscreen Noise Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing touchscreen technologies face challenges in optimizing fingerprint sensing performance while minimizing noise interference from touch sensing and display operations, leading to potential image quality degradation and reduced sensitivity in fingerprint and touch sensing capabilities.
Innovation Solution
A fingerprint controller and driver integrated circuit that synchronize touch sensing, fingerprint sensing, and display operations using timing signals to prevent noise interference, allowing for separate and staggered driving of touch sensing, fingerprint sensing, and display operations, ensuring optimal performance without overlapping intervals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If touch sensing, fingerprint sensing, and display operations are performed simultaneously, then overall system functionality is maintained, but noise interference increases and sensing performance degrades
Solution Approach 1:
The patent divides the sensing operations into separate time slots, with touch sensing, fingerprint sensing, and display operations performed sequentially rather than simultaneously. This temporal segmentation prevents noise interference from overlapping operations while maintaining all required functionalities.
Solution Approach 2:
The system implements periodic sensing cycles where touch sensing and fingerprint sensing are performed in alternating time slots synchronized with the display refresh cycle. This periodic action ensures that sensing operations occur only when the display is not updating, eliminating noise interference while maintaining continuous monitoring capability.
2Ease of operation
If fingerprint sensing and touch sensing are performed at the same time, then both functions remain responsive, but sensing accuracy and image quality deteriorate due to mutual interference
Solution Approach 1:
The patent segments the sensing array operations into dedicated time slots for touch sensing and fingerprint sensing. During fingerprint sensing time slots, only fingerprint detection is performed, ensuring high image quality. During touch sensing time slots, touch input detection is prioritized. This segmentation maintains responsiveness for both functions while preventing mutual interference.
Solution Approach 2:
The system dynamically adjusts the sensing mode based on timing signals, switching between touch sensing and fingerprint sensing operations. This dynamic time-division multiplexing allows the system to be responsive to both touch and fingerprint inputs while ensuring that each sensing type operates with full precision during its designated time slot.
3Productivity
If multiple sensing operations are performed concurrently, then system throughput is maintained, but the processing load on external hosts increases
Solution Approach 1:
The patent implements periodic sensing operations synchronized with display refresh cycles, where touch sensing and fingerprint sensing are performed in alternating time slots. This periodic approach maintains system throughput by ensuring continuous monitoring capability while reducing the instantaneous processing load on external hosts, as data is collected and prepared in a structured, time-division manner.
Data Source
AI summary
Provided are a fingerprint controller for driving a fingerprint sensing array in a touchscreen divided by at least a touch sensing region and a fingerprint sensing region, a method of operating the fingerprint controller, and a driver integrated circuit for driving the touchscreen including the fingerprint sensing array. The method includes: receiving a reference timing signal from an external module; generating a fingerprint sensing timing signal for driving the fingerprint sensing array in synchronization with the reference timing signal; and driving the fingerprint sensing array based on the fingerprint sensing timing signal.