Inexpensive multispectral imaging device

Abstract

Multi/hyperspectral imaging is an important technique to obtain color data and spectral monitoring. It is a precise remote sensing technique that includes two or more bands in the visible and invisible spectrum. This study demonstrates the design and construction of a low-cost, multispectral imaging system using a single linear array sensor and a varifocal lens coupled to individual spectral band-pass filters. The system allows the automated data acquisition of raw spectral data for seven spectral bands, each with different wavelengths. The raw data are visualized in real-time to generate images of spectral bands to obtain the desired spectral information on the computer graphical screen. Sensor arrays with spectral responsivity between 0.3 and 1.05 μm and motorized filter disks with a linear guide are used for acquiring data from specific wavelengths. Axis movement of the imaging device is achieved by a linear guide for spatial monitoring. Seven different bands are scanned and transferred to the computer via motorized band-pass filter sets with the imaging device. The multispectral imaging device has high accuracy with a 0.9936 linear correlation coefficient (r2) and averaged noise of the total system is below 1% (0.7%). Although the present configuration uses seven spectral bands including visible and narrow bandpass optical filters to obtain multispectral information from an object, the system is designed to have a replaceable and selectable motorized rotating filter, easily remounted, and adjusted up to forty spectral bands with 20 nm full width at half maximum (FWHM).