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Optics Express

Optics Express

  • Editor: Andrew M. Weiner
  • Vol. 22, Iss. 3 — Feb. 10, 2014
  • pp: 2259–2266

Continuous-wave terahertz system based on a dual-mode laser for real-time non-contact measurement of thickness and conductivity

Kiwon Moon, Namje Kim, Jun-Hwan Shin, Young-Jong Yoon, Sang-Pil Han, and Kyung Hyun Park  »View Author Affiliations

Optics Express, Vol. 22, Issue 3, pp. 2259-2266 (2014)

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Terahertz (THz) waves have been exploited for the non-contact measurements of thickness and refractive index, which has enormous industrial applicability. In this work, we demonstrate a 1.3-μm dual-mode laser (DML)-based continuous-wave THz system for the real-time measurement of a commercial indium-tin-oxide (ITO)-coated glass. The system is compact, cost-effective, and capable of performing broadband measurement within a second at the setting resolution of 1 GHz. The thickness of the glass and the sheet conductivity of the ITO film were successfully measured, and the measurements agree well with those of broadband pulse-based time domain spectroscopy and Hall measurement results.

© 2014 Optical Society of America

OCIS Codes
(120.4290) Instrumentation, measurement, and metrology : Nondestructive testing
(140.5960) Lasers and laser optics : Semiconductor lasers
(300.6495) Spectroscopy : Spectroscopy, teraherz

ToC Category:
Terahertz Optics

Original Manuscript: September 23, 2013
Revised Manuscript: December 10, 2013
Manuscript Accepted: January 22, 2014
Published: January 28, 2014

Kiwon Moon, Namje Kim, Jun-Hwan Shin, Young-Jong Yoon, Sang-Pil Han, and Kyung Hyun Park, "Continuous-wave terahertz system based on a dual-mode laser for real-time non-contact measurement of thickness and conductivity," Opt. Express 22, 2259-2266 (2014)

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