DocumentCode :
2970304
Title :
A Reflection Based, Pulsed THz Imaging System with 1 mm Spatial Resolution
Author :
Taylor, Z.D. ; Singh, R.S. ; Brown, E.R. ; Bjarnason, J.E. ; Hanson, M.P. ; Gossard, A.C.
Author_Institution :
Univ. of California Santa Barbara, Santa Barbara
fYear :
2007
fDate :
3-8 June 2007
Firstpage :
1161
Lastpage :
1164
Abstract :
Operating in reflection and using single pixel, whiskbroom scanning to generate images, we report on a THz imaging system with a spatial resolution of 1 mm and a post detection SNR of 67 dB. The source in the system is an ErAs:GaAs photoconductive switch, , and the detector is a waveguide mounted, zero-bias Schottky diode operating at a center frequency of 600 GHz and a 3 dB bandwidth of 200 GHz. The high output power of the photoconductive switch and large instantaneous bandwidth of both switch and detector allow the system to achieve this high post detection SNR in a 60 Hz bandwidth when reflecting off a specular metal target at a standoff of 4 cm. The spatial resolution is superior to that predicted by the standard Rayleigh criterion as expected from the systems´ Gaussian (non uniform) illumination, but is inferior to the Sparrow Criterion due to the presence of system noise, and discrete rounding of sample amplitudes.
Keywords :
Schottky diodes; erbium compounds; gallium arsenide; image resolution; lighting; photoconducting switches; submillimetre wave imaging; GaAs:ErAs; Gaussian illumination; bandwidth 200 GHz; bandwidth 60 Hz; frequency 600 GHz; high post detection SNR; noise figure 3 dB; noise figure 67 dB; photoconductive switch; pulsed THz imaging system; reflection; sparrow criterion; spatial resolution; standard Rayleigh criterion; system noise; whiskbroom scanning; zero-bias Schottky diode; Bandwidth; Detectors; Frequency; Image generation; Photoconductivity; Pixel; Reflection; Schottky diodes; Spatial resolution; Switches; Image resolution; Imaging; Submillimeter wave imaging; Submillimeter wave switches; Submillimeter wave technology;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Microwave Symposium, 2007. IEEE/MTT-S International
Conference_Location :
Honolulu, HI
ISSN :
0149-645X
Print_ISBN :
1-4244-0688-9
Electronic_ISBN :
0149-645X
Type :
conf
DOI :
10.1109/MWSYM.2007.380336
Filename :
4264035
Link To Document :
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