Biometric Sensor Parameter Adjustment for Illumination Variance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Fingerprint characteristic identification in mobile terminals and electronic products is hindered by poor identification effects due to different ambient illumination environments during the registration and matching stages, leading to low verification rates.
Innovation Solution
A biological data detection method and apparatus that determine the variation in light intensity between the registration and matching stages, adjusting parameters such as exposure time and ADC gain coefficients to approximate the image clarity and noise of the sensing unit, ensuring that the biological data detected at the matching stage is comparable to that at the registration stage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If fingerprint data is acquired at different ambient illumination environments during registration and matching stages, then the authentication process can be completed, but the fingerprint characteristic identification effect deteriorates and verifying rate decreases
Solution Approach 1:
The patent changes the operating parameters of the sensing unit based on ambient light intensity. Specifically, it adjusts the exposure time and ADC gain coefficient according to the detected ambient illumination level, allowing the system to maintain optimal fingerprint image quality across different lighting conditions during both registration and matching stages.
Solution Approach 2:
The system implements a feedback mechanism where the ambient light sensor continuously monitors the illumination environment and provides this information to the control unit. The control unit then adjusts the sensing unit parameters accordingly, creating a closed-loop system that adapts to changing light conditions and maintains consistent fingerprint image quality.
2Device complexity
If the sensing unit operates with fixed parameters during fingerprint acquisition, then the device complexity is reduced, but the image clarity and noise performance deteriorate under varying light conditions
Solution Approach 1:
The patent dynamically changes the exposure time and ADC gain coefficient parameters of the sensing unit based on ambient light intensity measurements. This allows the system to optimize fingerprint image quality for each lighting condition without requiring multiple hardware configurations, balancing complexity and performance.
3Manufacturing precision
If the exposure time and ADC gain coefficient are adjusted to match ambient light conditions, then the image clarity and noise performance improve, but the device complexity increases due to additional control mechanisms
Solution Approach 1:
The control unit serves multiple functions: it processes ambient light sensor data, calculates appropriate exposure time and ADC gain coefficient values, and adjusts the sensing unit parameters. This multi-functional approach avoids adding separate dedicated circuits for each function, thereby minimizing the increase in device complexity while achieving improved image quality.
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 improves the fingerprint identification performance by adjusting light intensity and operation parameters to match the ambient illumination conditions, enhancing the quality of fingerprint images and thereby improving identification accuracy.
Implementation Method 1
The sensing unit may calculate the light intensity in the ambient environment encompassing the sensing unit by receiving ambient light
Data Source
AI summary
A biological data detection method and a biological data detection device are provided. The method determines a variation in light intensity in an ambient environment encompassing a sensing unit at a biological characteristic matching stage compared to a biological characteristic registration stage, the sensing unit having a first value of a parameter at the biological characteristic matching stage and a second value of the parameter at the biological characteristic registration stage; obtaining the first value relative to the second value based on the variation in light intensity in an ambient environment such that image clarity and/or image noise of the biological image generated at the biological characteristic matching stage approximates image clarity and image noise of a biological image generated at the biological characteristic registration stage. The parameter of the sensing unit includes an exposure time and/or an ADC gain coefficient.