Optical Interferometer Ferrule Layout for Accurate LIDAR Velocity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The tilted input and output surfaces of the Fabry-Perot etalon in optical interferometers cause path length differences, leading to erroneous velocity projections in LIDAR systems.
Innovation Solution
Symmetrically dispose pairs of optical emitters around an axis in the ferrule, ensuring equal path lengths for received and reference optical signals, and avoid overlapping cross-sections to minimize interference patterns.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the input and output surfaces of the Fabry-Perot etalon are tilted to diminish undesired optical effects, then optical quality is improved, but path length differences cause erroneous velocity projections
Solution Approach 1:
The patent applies asymmetry by using different tilt angles for the input surface and output surface of the Fabry-Perot etalon. The input surface is tilted at a first angle while the output surface is tilted at a second angle that is different from the first angle. This asymmetric configuration allows the system to maintain the benefits of tilted surfaces for reducing undesired optical effects while compensating for path length differences to preserve velocity measurement accuracy.
2Adaptability or versatility
If multiple optical signals are emitted from different locations on the ferrule, then vector variables can be determined, but path length differences through the etalon cause measurement errors
Solution Approach 1:
The patent applies local quality by optimizing the specific tilt angles for each surface of the etalon based on its local function. The input surface has a tilt angle optimized for receiving optical signals from multiple ferrule locations, while the output surface has a different tilt angle optimized for maintaining equal path lengths through the etalon. This localized optimization allows the system to handle multiple signals for vector variable determination while maintaining measurement precision.
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
Reduces errors in velocity measurements by aligning path lengths and minimizing undesired interference patterns, enhancing the accuracy of LIDAR systems.
Implementation Method 1
The Fabry-Perot etalon includes first and second optically clear components which are separated, e.g., by free space. An input surface, of the first optically clear component, is configured to receive a Fabry-Perot etalon input optical signal from a first external component. The Fabry-Perot etalon output optical signal generates a desired interference pattern which is emitted as the output optical signal.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Techniques are provided for symmetrically locating optical emitters in a surface of a ferrule. Such symmetrical displacement of each pair of optical emitters diminishes differences in path lengths through which optical signals propagate in an optical interferometer with tilted input and/or output surfaces.