The optical filtering principles of AOTF and system architecture of AOTF hyperspectral imager have been presented. A field hyperspectral imaging system has been setup and been applied in the multi-scale remote sensing in Tibetan Plateau. Hyperspectral images of different scale have been collected in the experimental area for plateau vegetation, and more abundant field supporting and comparative data have been provided. By data processing, the engineering feasibility of the technique has been validated, and a novel method has been introduced for unmixing the mixed pixel in remote sensing images.