VCSEL Projector Beam Profiles for Single-Shot 3D Positioning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optical devices and methods for 3D measurements using structured light face challenges in determining the position of objects with high technical effort and resource requirements, particularly due to the correspondence problem of identifying which point on the object was generated by which light beam.
Innovation Solution
A projector using an array of vertical-cavity surface-emitting lasers (VCSELs) with unique beam profiles for each laser, combined with optical elements to generate distinct illumination patterns, allowing for reliable object positioning without the need for temporal modulation or multiple image sequences.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If structured light methods with point patterns are used for 3D measurements, then depth information can be obtained, but the correspondence problem arises requiring complex and time-consuming evaluation methods
Solution Approach 1:
Each VCSEL in the array is assigned a unique beam profile characteristic (different lateral and/or axial profiles) that serves as a local identifier. This allows each light beam to be individually recognized and traced back to its source VCSEL, eliminating the correspondence problem without requiring complex evaluation methods.
Solution Approach 2:
The invention uses different beam profiles (analogous to different colors or signatures) for each VCSEL's light beam. The optical system generates characteristic beam profiles that differ in lateral and/or axial directions, enabling the detector to distinguish and identify individual beams based on their unique profiles rather than requiring complex temporal modulation or multiple image sequences.
2Measurement precision
If conventional structured light methods are used, then object positioning is possible, but temporal modulation or multiple image sequences are required increasing time consumption
Solution Approach 1:
The unique beam profiles are pre-assigned to each VCSEL during system setup or manufacturing. This preliminary differentiation of beam characteristics allows for immediate identification of light beam sources during measurement, eliminating the need for temporal modulation or multiple image sequences and enabling single-shot 3D measurement.
3Reliability
If multiple optical elements with structured surfaces are used to generate distinct beam profiles, then light beam distinction is improved, but device complexity increases
Solution Approach 1:
The optical system is segmented into multiple optical elements (lenses or diffractive optical elements), with each element corresponding to a specific VCSEL. Each optical element is configured to generate a specific beam profile for its associated VCSEL, enabling individual beam differentiation through systematic division of the optical system.
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
Enables efficient and cost-effective determination of object positions in three-dimensional space by distinguishing light beams from individual VCSELs, reducing technical complexity and resource requirements.
Implementation Method 1
The projector comprises at least one array of vertical-cavity surface-emitting lasers (VCSELs), wherein each of the VCSELs is configured for generating at least one light beam
Implementation Method 2
The optical system comprises at least one array of optical elements, wherein each of the optical elements has a structured surface
Implementation Method 3
The optical system comprises at least one array of optical elements, wherein each of the optical elements has a structured surface
Data Source
AI summary
Disclosed herein is a projector for illuminating at least one object with at least one illumination pattern. The projector includes at least one array of vertical-cavity surface-emitting lasers (VCSELs). Each of the VCSELs is configured for generating at least one light beam. The projector includes at least one optical system configured for generating a characteristic beam profile for each of the light beams generated by the VCSELs of the array. The beam profile of neighboring VCSELs of the array differs in lateral and/or axial direction such that light beams of the VCSELs of the array are assignable to the corresponding VCSEL in three-dimensional space.