Photodiode Array Signal Summing for Light Spot Localization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optical detection and localization devices using four photodiodes face challenges in improving signal-to-noise ratio and accuracy in detecting and localizing light spots, particularly when light spots are off-center, leading to reduced performance in guiding vehicles towards light sources.
Innovation Solution
The device employs multiple optical sensors with combined fields, each comprising several photodiodes connected to a control unit that generates a stronger signal by summing signals from multiple photodiodes, while subtracting a secondary signal to reduce noise, and implements circular permutation and filtering to correct for sensitivity errors over time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If four photodiodes are used to detect light spots, then the device can determine the position of light spots, but the signal-to-noise ratio deteriorates when light spots are off-center
Solution Approach 1:
The patent combines multiple photodiodes into sensor groups (e.g., four photodiodes forming one sensor, with overlapping groups sharing common photodiodes). Each sensor group detects light spots from different angular positions, and their signals are combined to improve the signal-to-noise ratio while maintaining position determination accuracy across the entire field of view.
Solution Approach 2:
The detection field is segmented into multiple sensor groups, each responsible for detecting light spots from specific angular ranges. This segmentation allows the system to optimize detection for different regions while maintaining overall system performance through coordinated signal processing.
2Area of stationary object
If multiple optical sensors with combined fields are used, then the field of detection is improved, but the device complexity increases
Solution Approach 1:
The patent extends the detection capability from a single plane to multiple angular dimensions by arranging sensor groups to detect light spots from different angles. This dimensional extension increases the effective field of detection while managing complexity through systematic signal combination rules.
Solution Approach 2:
Each photodiode serves multiple functions by being shared among different sensor groups. A single photodiode can contribute to multiple sensors detecting light spots from different angular positions, reducing the total number of photodiodes needed while expanding the field of detection.
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 enhances the signal-to-noise ratio and improves the accuracy of light spot detection and localization, reducing noise and sensitivity errors, thereby enhancing the device's performance in guiding vehicles towards light sources.
Implementation Method 1
an optical sensor comprising four photodiodes which supply a signal proportional to a quantity of light energy received
Data Source
Figure 1~2
Figure 3
AI summary
Locating and detecting device comprising a plurality of optical sensors (Q1, Q2, Q3, Q4) having fields that add to define the field of the locating and detecting device, each sensor comprising a plurality of photodiodes having fields that add to define the field of the sensor, the sensors being connected to a control unit (10) in such a way that each sensor delivers a first signal corresponding to the sum of the signals of at least two of the photodiodes.