Multi-Source Laser Distance Measurement Without Scanning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing laser scanners for acquiring three-dimensional data are costly and complex, necessitating a more affordable and simpler method for obtaining point group data.
Innovation Solution
A measuring device with multiple light emitting sources arranged along a line, a light receiving optical system using optical fibers to guide reflected light to a photodetector, and a control unit that calculates distances based on time differences in photodetection signals, allowing for simultaneous distance measurement without scanning and reducing noise.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a laser scanner with deflection mirrors and rotating mechanisms is used to acquire point group data, then measurement precision and three-dimensional data acquisition capability are improved, but device complexity and cost increase
Solution Approach 1:
The invention divides the light source into multiple discrete light emitting sources arranged along a line, with each source corresponding to a specific measurement point. This segmentation eliminates the need for mechanical scanning while maintaining the ability to measure multiple points simultaneously, thereby reducing device complexity while preserving measurement precision.
Solution Approach 2:
The invention replaces the mechanical scanning system (deflection mirrors, rotating mechanisms) with a stationary optical system using multiple light emitting sources and optical fibers. This substitution eliminates moving parts and complex mechanical control while achieving the same function of acquiring three-dimensional point group data.
2Productivity
If multiple light emitting sources are used to measure multiple points simultaneously, then productivity is improved, but device complexity increases
Solution Approach 1:
The invention merges multiple optical measurement channels into a single photodetector by using optical fibers to guide light from multiple sources to one detection point. This consolidation allows simultaneous measurement of multiple points while simplifying the detection system, thereby improving productivity without significantly increasing device complexity.
Solution Approach 2:
The invention introduces optical fibers as intermediary elements to transmit light between the multiple light emitting sources and the single photodetector. This intermediary system enables efficient light guidance and signal collection, allowing parallel measurement of multiple points while maintaining a relatively simple overall device structure.
3Device complexity
If a single photodetector is used to detect reflected light from multiple light sources, then device complexity is reduced, but measurement precision may deteriorate due to signal mixing
Solution Approach 1:
The invention employs periodic alternation in the emission of light from different light sources, with each source emitting light in sequential time intervals. This time-division multiplexing approach allows a single photodetector to distinguish signals from different sources based on their temporal patterns, thereby maintaining measurement precision while using a simplified single-detector system.
Solution Approach 2:
The invention implements feedback control where the control unit monitors the timing and pattern of light emission from each source and correlates it with the corresponding detected signals. This feedback mechanism enables the system to accurately associate each detected signal with its originating light source, maintaining measurement precision despite using a single photodetector for multiple sources.
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
The device provides accurate and efficient point group data acquisition at a lower cost, enabling three-dimensional data collection without the need for complex scanning mechanisms, even when installed on mobile objects.
Implementation Method 1
a control unit for measuring a distance by measuring time from light emission of the pulsed distance measuring light to receipt of the reflected pulsed distance measuring light
Implementation Method 2
the light receiving part comprises a plurality of light receiving optical fibers for receiving the reflected pulsed distance measuring lights and a aggregate light optical fiber for binding the reflected pulsed distance measuring lights from the plurality of light receiving optical fibers in one bundle and for guiding the reflected pulsed distance measuring lights to the photodetector
Data Source
Figure 1A~1B
Figure 2A~2C
Figure 3A~3C
AI summary
The present invention provides a measuring device, comprising a light source unit 2 for projecting a pulsed distance measuring light 10 toward an object to be measured, a projecting light optical system 3 for projecting the pulsed distance measuring light emitted from the light source unit on the object to be measured, a light receiving optical system 4 for receiving a reflected pulsed distance measuring light 10' from the object to be measured, a light receiving part 6 having a single photodetector 12 for detecting the reflected pulsed distance measuring light as received, and a control unit 7 for measuring a distance by measuring time from light emission of the pulsed distance measuring light to receipt of the reflected pulsed distance measuring light based on a detection signal from the photodetector, wherein the light source unit has a plurality of light emitting sources 8 arranged in a known relation with respect to an optical axis of the projecting light optical system, and a driving unit 9 for driving the light emitting sources at a predetermined time interval, the light receiving part has a reduced optical system 11, 13 arranged at position conjugate to the light emitting source and used for guiding the reflected pulsed distance measuring light to the photodetector, and the control unit is designed to identify a photodetection signal 24 from the photodetector by matching with the light emitting source and to perform distance measurement for each photodetection signal.