Ghost imaging via spectral multiplexing in the broadband terahertz range

A method is proposed for accelerating measurements for ghost imaging reconstruction of objects using spectral multiplexing of speckle patterns formed by broadband terahertz (THz) radiation. The presented method aims at the challenge of a sufficiently large number of measurements, and increases the correlation between reference and reconstructed images. It is experimentally shown that unique speckle patterns for individual frequencies can be formed by broadband THz radiation while propagating through a random phase plate. It is shown by numerical simulation that these speckle patterns can be used to decrease the number of diffusers required by more than one order compared to the integrated method. The possibility of using electro-optical detection in the proposed technique reduces the number of measurements. For example, for the spectral range from 0.2 to 1.2 THz, there is a more than 20-fold decrease in the number of diffusers used. (c) 2022 Optica Publishing Group