Off-axis Lidar Radiation Source for Eye Safety and Range
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional lidar devices face limitations in achieving high transmission power while ensuring eye safety, particularly in applications requiring a large range, as they often operate at the maximum safe transmission power defined by laser class 1, which restricts their range and can pose risks due to beam intersection on the retina.
Innovation Solution
The lidar device positions its radiation source off-axis from the symmetry axis, preventing beam intersection and allowing for higher transmission power by expanding the apparent source size on the retina, thereby increasing the range and signal-to-noise ratio without compromising eye safety, and optionally uses multiple radiation sources positioned parallelly or asymmetrically to further prevent beam overlap.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the radiation source is positioned on the axis of symmetry, then the device structure is simple and alignment is easy, but the beam intersection on the retina creates eye safety risks and limits transmission power
Solution Approach 1:
The radiation source is deliberately positioned off-axis, creating an asymmetric beam path that prevents intersection with the optical axis. This asymmetric configuration ensures that reflected beams do not converge on the retina, eliminating the eye safety hazard while allowing higher transmission powers
2Length of stationary object
If the transmission power is increased to extend the detection range, then the range is improved, but the eye safety is compromised due to beam concentration on the retina
Solution Approach 1:
By positioning the radiation source off-axis, the beam paths are configured to miss the optical axis entirely. This prevents the concentration of multiple reflected beams on the retina, allowing transmission power to be increased for extended range without compromising eye safety
Solution Approach 2:
The problem is solved by transitioning from a one-dimensional axial configuration to a two-dimensional off-axis configuration. The radiation source and its reflected beams operate in a different spatial plane, preventing intersection with the optical axis and enabling higher power operation
3Measurement precision
If multiple radiation sources are used to improve signal strength, then the signal-to-noise ratio is improved, but beam overlap increases the eye safety risk
Solution Approach 1:
Multiple radiation sources are positioned at different off-axis locations, creating asymmetric beam paths for each source. This ensures that even with multiple high-power sources, the reflected beams do not converge on the retina, maintaining eye safety while improving signal strength through multiple independent detection channels
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 configuration enables increased transmission power and range while ensuring eye safety by preventing beam intersection, resulting in improved performance without additional risk to human eyes, and allows for a more efficient scanning method using off-axis or parallel beam paths.
Implementation Method 1
The at least one radiation source generates the at least one beam at a distance from an axis of symmetry of the lidar device; the at least one beam traveling at a distance from the axis of symmetry
Implementation Method 2
A receiving unit is used for receiving at least one beam reflected by an object and for deflecting the at least one reflected beam onto a detector
Implementation Method 3
The at least one beam generated has an optical path, which does not intersect the axis of symmetry of the lidar device and is produced to be set apart from the axis of symmetry. Consequently, the at least one radiation source is positioned off-axis. In this manner, the lidar device may be prevented from acting as a virtual point source
Data Source
AI summary
A lidar device is described for scanning a region to be scanned, using at least one beam. The device includes at least one radiation source for generating the at least one beam, as well as a receiving unit for receiving at least one beam reflected by an object and for deflecting the at least one reflected beam onto a detector. The at least one radiation source generates the at least one beam away from an axis of symmetry, and the at least one beam traveling at a distance from the axis of symmetry. A method for scanning a region to be scanned is also described.