Single-Shot Multispectral Image Acquisition for Low-Altitude Remote Sensing using Light Diffraction Techniques

Multispectral imaging devices currently being used in a variety of applications typically follow opto-mechanical designs. These designs often present the disadvantage of a bulky and heavy construction, limiting their applicability in new low-altitude remote sensing applications deployed on acquisition systems with constrained weight and dimension requirements. This paper presents the design and construction of a simple optical system based on a transmission grating and a lightweight commercial camera for snapshot multispectral image acquisition. The system can be mounted on a small drone for low-altitude aerial remote sensing, and is capable of separating the spectral information from the spatial scene and generating multispectral HD images and 4K videos. In addition, we propose a fast algorithm for recovering multispectral scenes from their respective acquired spectral projections. Experimental results show similarity of the compared waveforms, and that the maximum peak of the reconstructed wave-length varies up to 13nm from reference spectroradiometer data.