Abstract-Focus free terahertz reflection imaging and tomography with Bessel beams

S. F. Busch, 

G. E. Town, 

M. Scheller, 

M. Koch

http://link.springer.com/article/10.1007/s10762-014-0129-1


A broadband terahertz (THz) reflection imaging system with high spatial resolution over a large depth of field is reported. A THz axicon lens producing a truncated THz Bessel beam with a linear focus exceeding 120 mm in length, and with the diameter of the central lobe less than 2 mm was used for imaging in a reflection geometry employing a pulsed THz time-domain spectrometer. With numerical post-processing, it was possible to reconstruct the three dimensional shape of the scanned object