VCSEL Array Laser Source for Hybrid 3D Imagers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current hybrid three-dimensional imaging systems face challenges with high costs due to separate illumination systems for time-of-flight, structured-light, and stereovision technologies, and difficulties in achieving fast switching speeds and efficient light utilization.
Innovation Solution
A compact laser source utilizing a monolithically integrated VCSEL array with independent electrical connections and integrated transistors for fast switching, combined with a switchable diffuser for adaptable illumination modes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If separate illumination systems are implemented for different 3D imaging techniques, then each technique can achieve its specialized performance requirements, but the system cost increases significantly and integration becomes difficult
Solution Approach 1:
The patent combines multiple illumination systems for different 3D imaging techniques (time-of-flight, structured-light, stereovision) into a single integrated laser source. This is achieved by implementing a unified laser array that can be selectively modulated to generate different illumination patterns suitable for various imaging methods, thereby reducing system complexity and integration difficulties while maintaining specialized performance for each technique
Solution Approach 2:
The laser source is designed with multi-functionality to serve multiple 3D imaging techniques simultaneously. The single laser array can be configured through electronic control to produce different illumination patterns and characteristics required by time-of-flight cameras, structured-light systems, and stereovision imaging, eliminating the need for separate dedicated illumination systems for each technique
2Illumination intensity
If high power lasers are used for each illumination system, then the required illumination intensity is achieved, but the cost contribution increases significantly
Solution Approach 1:
The patent merges multiple high-power laser systems into a single laser array source. By sharing one high-power laser source across multiple illumination functions and techniques, the total system cost is reduced while still achieving the required illumination intensity for each imaging technique through electronic beam control and modulation
Solution Approach 2:
The single laser source is designed to provide universal illumination for multiple techniques. Through selective activation and modulation of individual laser elements or groups within the array, the system achieves high illumination intensity requirements for different imaging methods without needing multiple separate high-power laser systems, thereby reducing overall cost
3Speed
If large currents are used for fast switching of VCSEL arrays, then switching speed is improved, but the inductance of leads limits achievable switching speeds
Solution Approach 1:
The patent replaces traditional mechanical or external current switching systems with integrated semiconductor switching elements (transistors) that are monolithically integrated directly with the VCSEL array. This substitution eliminates the need for external leads and their associated inductance, enabling faster switching speeds by directly controlling the current at the laser element level without the limitations of lead inductance
4Shape
If masks are used in the output beam for structured-light field generation, then the illumination pattern is created, but light is lost at the mask reducing efficiency
Solution Approach 1:
The patent replaces physical masks with mechanical light blocking elements with an electronic control system. By using individually addressable VCSEL elements or groups within the array, the desired structured-light patterns are generated through selective activation of laser elements rather than physical masking. This electronic approach eliminates light loss at masks while maintaining the ability to create complex illumination patterns
Solution Approach 2:
The patent changes the approach from passive optical masking to active electronic control of light emission. By varying the electrical parameters (current, timing, pattern) of individual VCSEL elements, the system dynamically generates structured-light patterns without physical masks, thereby eliminating energy loss while achieving the required illumination shapes
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 solution reduces costs, enhances precision and reliability by integrating multiple illumination techniques into a single system, enabling high-frequency modulation and flexible illumination patterns for improved 3D data quality and adaptability to varying conditions.
Implementation Method 1
The light source is based on monolithically integrated VCSELs in an array
Implementation Method 2
a switchable diffuser element in front the light source, which allows a switching between a structured-light field illumination mode and an illumination with a smooth, unstructured light field
Data Source
AI summary
The invention generally relates to hybrid three-dimensional imagers and to a laser source for active illumination for hybrid three-dimensional imagers (i.e. 3D imagers that make combined use of different 3D imaging technologies). The invention is applicable to three-dimensional imaging systems which use a combination of different imaging techniques (hybrid technologies) to achieve a higher precision or a higher level of reliability.