Rectangular-shaped sub-wavelength terahertz beam profiling via an all-optical knife-edge technique

Super resolution terahertz imaging by subpixel estimation: application to hyperspectral beam profiling

“…For these reasons, many efforts were made recently for the characterization of the beam profile for THz radiation [6][7][8][9][10][11][12] and for the development of high resolution imaging techniques [13,14]. Our approach is different.…”

“…Many profiling methods [6,[8][9][10][11] requires a significant rearrangement of the imagistic setup. Nowak et al [6] and Ho et al [8] used knife edge techniques. Abraham et al [9] and Bitzer at al [10] used wavefront sensors.…”

“…Our imaging parameters such as the image resolution of only 8×8 pixels, with a pixel size of 3×3 mm are modest compared to those from [6][7][8][9][10][11][12][13][14]; however, they are the parameters of the system we used, determined by the available hardware, not of the method itself, which can be implemented with a variety of equipment. There are no immediate principle limitations that apply to our method.…”

“…In order to increase the imaging resolution, one simply has to decrease the size of the raster steps and, consequently, to increase their number; the problem is that with the THz time-domain spectroscopy (THz-TDS) system we used, the time required to perform the scan becomes astronomical. References [6][7][8][9][10][11][12][13][14] used sophisticated equipment and mathematics to increase the resolution.…”