Paper
4 August 2009 The use dielectric-coated metal hollow fiber for terahertz wave metal underground sensors
Ke-jia Wang, Qi Wang, Yi Wang, Shuai Zhang
Author Affiliations +
Abstract
Transmission characteristics and mode structure of both metal hollow fiber and dielectric-coated metal hollow fiber for terahertz wave are studied. Theoretical evaluation shows that the TE11mode is dominant in metal hollow fiber and has high coupling efficiency when a linearly polarized light source is launched. HE11mode is mainly supported in dielectric-coated metal hollow fiber with an optimum thickness for the dielectric film. The transmission loss of the TE11and HE11mode is8.4dB/m and 2dB/m respectively at the wavelength of 200μm for the hollow fibers with 1mm bore size. The effects of optical constants of metals and dielectric materials on attenuation coefficient are also discussed to optimize the transmission performance of dielectric-coated metal hollow fiber.Aluminum is the best choice among the commonly-used metals based on published optical constants. The optimum value for the refractive index of the dielectric film is1.41. According to the primary measuring results, polyethylene is a proper choice as its refractive index is1.51and it brings low absorption in terahertz waves. The use of Dielectric-Coated Metal Hollow Fiber Bragg phase-shifted fiber grating, for optical fiber and metal combine downhole drill pipe deformation temperature and strain detection underground. Phase-Shifted Fiber Bragg Grating using photoelectric heterodyne detection frequency, the frequency range up to 1012Hz, the frequency resolution of 1KHz. LPFG, photovoltaic devices and microwave heterodyne frequency meter combination can solve the phase-shift grating sensor speed and resolution issues.
© (2009) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Ke-jia Wang, Qi Wang, Yi Wang, and Shuai Zhang "The use dielectric-coated metal hollow fiber for terahertz wave metal underground sensors", Proc. SPIE 7385, International Symposium on Photoelectronic Detection and Imaging 2009: Terahertz and High Energy Radiation Detection Technologies and Applications, 738522 (4 August 2009); https://doi.org/10.1117/12.836001
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Metals

Sensors

Phase shifts

Optical fibers

Terahertz radiation

Heterodyning

Structured optical fibers

Back to Top