Monitoring System with Block-Based LED Illumination for Face Authentication
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional face authentication systems using monitoring cameras struggle with maintaining consistent brightness across varying distances, leading to dark faces of distant subjects and bright faces of nearby subjects due to the inverse square law of illumination, limiting the effective image capturing distance for appropriate brightness.
Innovation Solution
A monitoring system that includes a monitoring device with multiple sets of LEDs and diffractive optical elements, which divides the image capturing range into blocks and controls the light emission intensity of each block based on the position or size of the face area within the image, ensuring constant brightness by adjusting light emission according to the image capturing distance or face size.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If a single illumination device is used to irradiate the entire image capturing range, then the device complexity is low, but the illumination intensity becomes insufficient for distant subjects due to the inverse square law
Solution Approach 1:
The image capturing range is divided into multiple blocks, with each block illuminated by a dedicated light emitting element. This segmentation allows each element to focus illumination on a specific region, maintaining adequate brightness even for distant subjects without requiring a single high-power illumination device.
Solution Approach 2:
Different regions of the image capturing range receive customized illumination based on their specific requirements. The control device adjusts the light emission intensity of each light emitting element according to the detected face area position and size, providing locally optimized illumination quality throughout the entire field of view.
2Illumination intensity
If the light emission intensity is increased to illuminate distant subjects, then the illumination intensity is sufficient, but nearby subjects become overexposed and too bright
Solution Approach 1:
The illumination system dynamically adjusts the light emission intensity of each light emitting element based on real-time detection of face area position and size. This dynamic control prevents overexposure of nearby subjects while ensuring adequate illumination of distant subjects, maintaining optimal image quality across varying distances.
Solution Approach 2:
The control device changes the illumination parameters (light emission intensity) of each light emitting element according to the detected face area characteristics. By adjusting these parameters based on position and size information, the system achieves consistent image quality for subjects at different distances without overexposure or underexposure.
3Manufacturing precision
If the illumination is adjusted for each block based on face position and size, then the image quality is maintained, but the control complexity increases
Solution Approach 1:
The system uses the captured image data itself to automatically determine the face area position and size, which then directly controls the illumination adjustment. This self-service approach eliminates the need for separate complex control mechanisms, as the image processing and illumination control are integrated through a unified feedback loop.
Solution Approach 2:
The control device continuously monitors the captured images, detects face area characteristics, and uses this feedback to adjust the light emission intensity of corresponding light emitting elements. This closed-loop feedback system maintains optimal image quality while automating the control process, reducing manual intervention requirements.
4Illumination intensity
If multiple light emitting elements are used to cover the entire image capturing range, then the illumination intensity is sufficient across all areas, but the energy consumption increases
Solution Approach 1:
Instead of continuously activating all light emitting elements at full intensity, the system activates only the necessary elements and adjusts their intensity based on actual illumination needs detected in each scene. This partial action approach ensures sufficient illumination where required while minimizing energy consumption in areas where full illumination is not needed.
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 solution allows for capturing a subject's face with consistent brightness regardless of the distance, improving image quality and enabling effective face authentication even as the surrounding environment changes.
Implementation Method 1
a plurality of light emitting elements 201 that irradiate an image capturing range of the image capturing unit 111
Implementation Method 2
a plurality of diffractive optical elements 202 that correspond to a plurality of blocks that divide a captured image
Data Source
AI summary
A monitoring system includes a memory, and a processor coupled to the memory and configured to detect a face area of a subject from a captured image divided into a plurality of blocks according to a number of light emitting elements that irradiate an image capturing range, and control a light emission intensity of a light emitting element corresponding to a block including the face area among the plurality of blocks according to one of a position of the face area and a size of the face area.