Tunable SWIR Spectral Imaging for Appearance and Interior Inspection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional spectral imaging methods require separate systems for appearance and see-through inspection of objects, often involving X-rays, which are costly and require significant safety measures, and they are limited in wavelength selection, preventing simultaneous wide-band detection.
Innovation Solution
A spectral imaging system using a tunable light source with a filter unit comprising wheel filters and a detection unit capable of detecting a wide wavelength band, allowing simultaneous appearance and see-through inspection by selecting specific wavelengths through rotation and adjustment of incident angles.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If X-rays are used for see-through inspection of the inside of a product, then inspection capability is improved, but device complexity and safety requirements increase significantly
Solution Approach 1:
The patent changes the wavelength parameter of the light source from conventional visible/UV ranges to short-wave infrared range (1000-2000 nm). This parameter change enables see-through inspection of semiconductor wafers without requiring X-ray facilities, as silicon is transparent to SWIR light. The detection unit captures transmitted light images to reveal internal defects, achieving X-ray-like inspection capability with a simpler, safer system.
Solution Approach 2:
The patent replaces the mechanical and safety-intensive X-ray inspection system with an optical system using SWIR light sources and detectors. This substitution eliminates the need for radioactive sources, complex shielding facilities, and specialized safety protocols while maintaining the core function of internal defect detection through see-through imaging.
2Adaptability or versatility
If a spectrometer is mounted in front of a hyperspectral camera for spectral imaging, then wavelength selection capability is improved, but the detection side equipment becomes large and complex
Solution Approach 1:
Instead of placing a spectrometer at the detection side to select wavelengths after light capture, the patent inverts the approach by using a tunable SWIR light source that emits only the desired wavelength range (1000-2000 nm). The filter unit is positioned at the light source side, allowing wavelength selection before illumination, thereby eliminating the need for complex spectral separation equipment at the detector.
Solution Approach 2:
The patent extracts the wavelength selection function from the detection path and relocates it to the illumination path. By placing the filter unit in the light source assembly rather than in front of the camera, the system removes the bulky spectrometer from the detection side while preserving spectral imaging capability through selective SWIR illumination.
3Measurement precision
If light of a specific wavelength is radiated to perform spectral imaging, then detection precision for specific features is improved, but the wavelength band range that can be detected is limited to a narrow band
Solution Approach 1:
The patent employs a tunable light source with a filter unit that can dynamically adjust the emitted wavelength within the SWIR range (1000-2000 nm). By rotating the filter wheel to select different bandpass filters, the system can adaptively change the wavelength being emitted and detected. This dynamic adjustment enables the same hardware to optimize detection precision for different material properties and defect types across a wide spectral range.
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 simultaneous acquisition of various information on an object's appearance and interior using ultra-wideband tunable light, reducing costs and complexity without the need for X-ray safety equipment.
Implementation Method 1
a filter unit for allowing light having a specific wavelength in the specific wavelength band of the light radiated from the light source to be passed through it
Implementation Method 2
a detection unit for detecting an image of the object with respect to the specific wavelength of the light passed through the filter unit and radiated to the object
Data Source
AI summary
Spectral imaging inspection method and system for selecting light having a specific wavelength in ultra-wideband wavelengths. A light source radiates light having a specific wavelength band, and a filter unit allows light having a specific wavelength in the specific wavelength band of the light radiated from the light source to be passed through it. A detection unit detects an image of the object with respect to the specific wavelength of the light passed through the filter unit and radiated to the object. The specific wavelength band includes a first wavelength, a second wavelength, and a third wavelength, wherein the light of the first wavelength is reflected by the object, only part of the light of the second wavelength penetrates the object, and the light of the third wavelength penetrates the object, and the third wavelength is a wavelength band of short wave infrared rays of 1000 nm or more.