Active and low-cost hyperspectral imaging for spectral analysis in low lighting environment

Hyperspectral imaging can capture information beyond conventional RGB cameras; thus, it has many applications, such as material identification and spectral analysis. However, like many camera systems, most of the existing hyperspectral cameras are still passive imaging systems: they require external light sources to illuminate the objects to capture the spectral intensity. As a result, the collected images highly depend on the environment lighting, and the imaging system cannot function in a dark or low-lighting environment. This work develops a prototype system for active hyperspectral imaging, which actively emits different single-wavelength lights at different frequencies when imaging. This concept has several advantages: first, using the controlled lighting, the magnitude of the individual bands is normalized to extract reflectance information; second, the system is capable of collecting information at the desired spectral range by tailoring the light sources; third, an active syste..., While capturing a hyperspectral image of an object, the system will loop over all 19 channels of LED lights and capture a panchromatic image for each of them.
The illuminator consists of totaling four concentric circle rings. Each ring consists of 19 LED lights and has the same LED light bulbs to form a cluster that emits light at the same wavelength. The four LED lights for each cluster are placed at a 90 interval to create sufficiently strong illumination, at the same time as distributed as possible to reduce the creation of shadows by direct lighting. The illuminator can illuminate lights at 19 unique wavelengths, and its actual implementation was achieved through planting these LED lights onto a circular PCB (Printed Circuit Board), powered by a 3W DC supplier and controlled through electrical switches. Each LED bulb has a dimension of 3.45mm x 3.45mm, driven by a direct current power supply.
The selection of these 19 individual LEDs aims to cover the spectrum ranges as wide as poss..., These hyperspectral images may use any image viewer to open.