3D Depth Sensor Multi-Wavelength Optical Shutter
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current 3D depth sensors using the time-of-flight method face challenges in accurately measuring distance information due to limitations in wavelength diversity and optical shutter design, leading to potential motion blur and reduced accuracy in depth detection.
Innovation Solution
A 3D depth sensor system incorporating multiple light sources with different center wavelengths (800-1100 nm) and an optical shutter with distinct areas to modulate and filter the reflected light, allowing for simultaneous irradiation and precise phase difference measurement, thereby enhancing depth information accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single light source is used in the 3D depth sensor, then the device complexity is reduced, but the measurement precision and depth detection accuracy deteriorate due to limitations in wavelength diversity
Solution Approach 1:
The patent divides the light source into multiple independent light sources emitting at different center wavelengths (e.g., 850nm, 940nm, 1064nm). Each light source corresponds to a specific wavelength band, allowing the system to capture depth information across multiple spectral regions simultaneously, thereby improving measurement precision without excessive complexity increase
Solution Approach 2:
The optical shutter is designed to perform multiple functions: it acts as a mechanical shutter for temporal gating, an optical filter for wavelength selection, and a phase modulator for TOF measurement. By integrating these functions into a single component, the patent improves measurement capabilities while controlling device complexity
2Illumination intensity
If the optical shutter allows broad spectral transmission, then the light intensity is sufficient for detection, but the measurement precision deteriorates due to inability to filter specific wavelength bands
Solution Approach 1:
The optical shutter incorporates wavelength-selective filtering regions with different transmittance characteristics. Each region is optimized to transmit specific wavelength bands (e.g., one region transmits 850nm light while blocking others, another transmits 940nm, etc.), allowing the system to maintain sufficient light intensity for each wavelength band while achieving precise wavelength selection
Solution Approach 2:
The optical shutter uses electrochromic or liquid crystal materials that can dynamically adjust their transmittance properties. By applying different voltages to different regions of the shutter, the system can dynamically control which wavelength bands are transmitted, enabling flexible wavelength selection while maintaining adequate light intensity for detection
3Measurement precision
If the optical shutter response time is extended to improve phase measurement accuracy, then the measurement precision improves, but the productivity decreases due to reduced frame rates
Solution Approach 1:
The patent uses multiple light sources emitting at different center wavelengths simultaneously, each modulated at different frequencies or phases. The optical shutter synchronizes with these periodic modulations to perform phase measurements. By using multiple wavelength channels in parallel, the system achieves high phase measurement accuracy while maintaining high frame rates through parallel processing
Solution Approach 2:
The patent extends the measurement from a single wavelength dimension to multiple wavelength dimensions. By capturing depth information at multiple center wavelengths (850nm, 940nm, 1064nm, etc.) simultaneously through the optical shutter, the system achieves higher measurement precision through multi-dimensional data fusion while maintaining high productivity through parallel wavelength acquisition
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 system achieves improved accuracy and reduced motion blur by using multiple light sources and an optical shutter with tailored transmittance profiles, enabling more precise distance measurement and higher frame rates for accurate 3D imaging.
Implementation Method 1
an optical shutter configured to allow reflected light reflected from the object to pass through
Implementation Method 2
an image sensor configured to filter the reflected light having passed through the optical shutter and detect the filtered light
Implementation Method 3
The TOF method measures a flight time of light reflected from an object and received by a sensor after having been irradiated to the object
Data Source
AI summary
A three-dimensional (3D) depth sensor may include: a plurality of light sources configured to irradiate light to an object, the light having different center wavelengths; an optical shutter configured to allow reflected light reflected from the object to pass through; and an image sensor configured to filter the reflected light having passed through the optical shutter and detect the filtered light.