Image Reconstruction and Optimization Using a Terahertz Scanned Imaging System

Date

2014-09-23

Author

Yildirim, Ihsan Ozan
ÖZKAN, VEDAT ALİ
Idikut, Firat
Takan, Taylan
ŞAHİN, ASAF BEHZAT
Altan, Hakan

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Due to the limited number of array detection architectures in the millimeter wave to terahertz region of the electromagnetic spectrum, imaging schemes with scan architectures are typically employed. In these con fi gurations the interplay between the frequencies used to illuminate the scene and the optics used play an important role in the quality of the formed image. Using a multiplied Schottky-diode based terahertz transceiver operating at 340 GHz, in a stand-o ff detection scheme; the e ff ect of image quality of a metal target was assessed based on the scanning speed of the galvanometer mirrors as well as the optical system that was constructed. Background e ff ects such as leakage on the receiver were minimized by conditioning the signal at the output of the transceiver. Then, the image of the target was simulated based on known parameters of the optical system and the measured images were compared to the simulation. By using an image quality index based on chi(2) algorithm the simulated and measured images were found to be in good agreement with a value of chi(2) = 0.14. The measurements as shown here will aid in the future development of larger stand-o ff imaging systems that work in the terahertz frequency range.

Subject Keywords

Terahertz, Mirror galvanometer system, Scanned imaging system

URI

https://hdl.handle.net/11511/40911

DOI

https://doi.org/10.1117/12.2064827

Collections

Department of Physics, Conference / Seminar

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Citation Formats

I. O. Yildirim, V. A. ÖZKAN, F. Idikut, T. Takan, A. B. ŞAHİN, and H. Altan, “Image Reconstruction and Optimization Using a Terahertz Scanned Imaging System,” 2014, vol. 9250, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/40911.