What is Hyperspectral Imaging?
The way in which light interacts with materials offers a way to identify them and study their properties. Hyperspectral imaging (HSI) combines digital imaging with spectroscopy – it provides spectral information in each image pixel.
Hyperspectral imaging can be used in reflection, transmission, or emission measurements. It is a non-destructive method for analysis and data collection across a wide variety of applications.
A hyperspectral camera collects and processes information by measuring the light interaction (reflection, transmission or emission) in order to obtain the Spectrum – the fingerprint - for each pixel in the image of a scene, with the purpose of finding objects, identifying materials or detecting processes.
What does a Spectrum tell us?
Every single point in an object has its own unique spectral fingerprint – the spectrum.
Spectra can be used to identify and separate different materials and objects.
Hyperspectral Camera Ranges
Hyperspectral imaging cameras, collects and processes information in order to obtain the spectral information for each pixel in the image of a scene, with the purpose of finding objects, identifying materials, or detecting processes.
Whereas the human eye sees color of visible light in mostly three bands (red, green, and blue), spectral imaging divides the spectrum into many more bands. This technique of dividing images into bands can be extended beyond the visible. In hyperspectral imaging, the recorded spectra have fine wavelength resolution and cover a wide range of wavelengths:
MWIR Cameras (3 - 5 µm)
Applications of Hyperspectral Cameras
- Printing process monitoring
- Display quality & color accuracy
- Color conformity check of manufactured products
- Art analysis & restoration
- Plant disease and stress detection, phenotyping
- Food, fruit, vegetable, grain, seed quality sorting
- Forensics sample and crime scene inspection
- Skin anomalies detection
- Life sciences
- Waste material sorting & recycling.
- Sorting of dangerous construction waste and medical waste, without human error
- Bulk material monitoring, moisture content, foreign material detection
- Composition of pharmaceutical products
- Quality of food raw materials & products
- Mineral mapping of geological samples
- Threat detection
- Geological exploration
- Environmental health
- Inspection of man-made infrastructure
- Precision Agriculture
- Law enforcement & military
Examples of Hyperspectral Imaging Applications
Fake Pharmaceutical Sample Detection
Three blister packages that were identical in visual inspection were measured. Packages contained white Ibuprofen and Parasetamol tablets. Before measurement one pill from one of the packages was removed and replaced with wrong type. Hyperspectral imaging clearly visualized the substituted tablets.
Data processing included reflectance calculation and first derivative calculation before making principal component analysis using the Perception Studio software.
Classification was done using the first and second component.
Hyperspectral imaging is a powerful tool to monitor food quality, composition and attributes. It can be used to verify food safety and manufacturing consistency.
In today’s world, different displays have a notable role in our daily life. HSI offers a straightforward way to monitor the quality of TV and computer screen, tablets and cell phones.
Hyperspectral imaging was originally developed for the mining and geology industries. It is an ideal method for identifying commercially valuable minerals in core samples or identifying the presence of ore or oil.