ToF Camera Interference Mitigation via Autonomous Slot Selection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Time-of-flight cameras experience mutual disturbances and errors in depth calculation due to extraneous light from other cameras, leading to inaccurate depth information, especially in applications where cameras overlap, and current networking solutions are costly and complex.
Innovation Solution
A method where a time-of-flight camera detects the presence of modulated light from other cameras and adjusts its recording mode, such as interrupting image recording or changing modulation frequency, to minimize interference without the need for network communication, allowing autonomous synchronization and improved depth information accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If multiple ToF cameras operate simultaneously in overlapping visual ranges, then monitoring coverage is improved, but mutual disturbances from extraneous light cause errors in depth calculation
Solution Approach 1:
The patent implements periodic time slots for light emission, where each camera is assigned specific time windows to emit modulated light. This temporal segmentation allows multiple cameras to operate in the same spatial area without mutual interference, as each camera emits light only during its designated period. The image sensor corresponds these time slots to specific cameras, enabling accurate depth calculation despite multiple cameras being present.
2Measurement precision
If networking is used to synchronize cameras and prevent disturbances, then depth calculation accuracy is improved, but device complexity and equipment needs increase
Solution Approach 1:
The patent enables each ToF camera to autonomously determine which time slot it should emit light based on its identification. The image sensor automatically correlates detected light with the corresponding time slot and camera ID without requiring external network coordination. This self-organizing approach eliminates the need for complex networking infrastructure while maintaining synchronization and preventing mutual disturbances.
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 reduces mutual disturbances between cameras, enhancing image quality and depth information precision without increasing equipment needs or network complexity, enabling efficient and reliable imaging even in overlapping visual ranges.
Implementation Method 1
the calculation of depth information from the propagation time of the modulated light between the emission and the detection
Implementation Method 2
the detection of modulated light after the reflection on objects of the scene using the image sensor
Implementation Method 3
An image sensor in the form of a PMD chip (photonic mixer device) for example can perform background light suppression for each pixel
Data Source
AI summary
The invention relates to a method for recording a scene (3) using at least two time-of-flight cameras (1, 2), which respectively comprise a light source (5) and an image sensor (6), wherein image recording operations which comprise a measuring operation for determining depth information are carried out using each of the at least two time-of-flight cameras (1, 2), wherein the measuring operation comprises the emission of modulated light (11) by the light source (5), the detection of modulated light (12) after the reflection on objects (4) of the scene (3) using the image sensor (6), and the calculation of depth information from the propagation time of the modulated light between the emission and the detection.In order to increase the image quality, a first time-of-flight camera (1) uses the measurement results of the measuring operation carried out by said camera to determine the extent to which modulated light from a second time-of-flight camera (2) was also detected in this measuring operation in addition to the light (11) emitted by its own light source (5), and the first time-of-flight camera (1) changes the recording mode thereof on the basis of the result of this determination.