Abstract: In order to solve the problem of simultaneous, object imaging and contrast demonstrating in near ultraviolet, visible light and near-infrared, the design thinking of constructing an imaging contrast demonstrating system was put forward. Three parts of image collectors, signal processing platform and image output projections was designed and constructed. A tri-band simultaneous and actual output demonstrating platform was established. From the spectral response verification of platform, and the imaging contrast of the human-made such as paint, color chip, fabrics patterns and artificial plants, the purpose of tri-band simultaneous and contrast imaging was realized.