Fingerprint Recognition Using Frequency-Division Multiplexing
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Solution Overview
Problem
Current fingerprint recognition methods using photosensitive devices to detect patterns by driving gate lines line by line result in a long detection time and slow response due to sequential activation of gate lines.
Innovation Solution
A fingerprint recognition apparatus with m driving signal lines and n reading signal lines arranged crosswise, featuring m*n photosensitive devices in a matrix form, where electrode signal controllers input driving signals of different frequencies simultaneously to rows of photosensitive devices, and a demodulator demodulates electrical signals of different frequencies on reading signal lines, allowing for simultaneous driving of multiple rows in each time period.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If gate lines are driven line by line sequentially, then the structure is simple and easy to control, but the detection time is long and response speed is slow
Solution Approach 1:
The gate lines are divided into multiple groups, with each group driven by a separate electrode signal controller. This segmentation allows parallel driving of multiple gate line groups simultaneously, reducing detection time while maintaining manageable control complexity through modular architecture
Solution Approach 2:
The patent transitions from sequential one-dimensional driving to parallel multi-dimensional driving by introducing multiple electrode signal controllers that operate simultaneously on different gate line groups, adding a temporal parallelism dimension to the control process
2Speed
If multiple rows of photosensitive devices are driven simultaneously, then detection speed is improved, but signal interference and control complexity increase
Solution Approach 1:
Different electrode signal controllers drive different gate line groups at different time periods or with different frequencies. This periodic/staggered action allows simultaneous driving of multiple rows while avoiding signal interference through temporal separation, and maintains control simplicity through structured timing control
Solution Approach 2:
The electrode signal controllers act as intermediary devices between the control system and the photosensitive devices. Each controller manages a specific group of gate lines, simplifying the overall control architecture while enabling parallel operation through distributed control
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 approach significantly reduces fingerprint detection time by enabling simultaneous activation of multiple rows of driving signal lines, improving the response speed of fingerprint recognition.
Implementation Method 1
light of different intensities can be converted into photocurrents of different magnitudes using photosensitive devices. Thus, owing to the difference between valleys and ridges of the fingerprint, reflected light of different intensities can be generated when a finger is irradiated by a light source. Thereby different photocurrents can be generated.
Data Source
AI summary
A fingerprint recognition apparatus is provided. The fingerprint recognition apparatus includes m driving signal lines, n reading signal lines, and m*n photosensitive devices. Each of a plurality of electrode signal controllers is connected to at least two of the m driving signal lines, the plurality of electrode signal controllers are configured to simultaneously input driving signals of different frequencies to each of the m driving signal lines connected to the plurality of electrode signal controllers, and a demodulator is connected to the n reading signal lines, and is configured to demodulate electrical signals of different frequencies transmitted on each of the n reading signal lines.