Year: 2025
Type: conference-paper
Abstract: Interference caused by multiple reflections is a critical issue in transmission measurements using continuous wave (CW) terahertz and sub-terahertz radiation. This study proposes a practical method to reduce interference effects and improve the stability of transmittance measurements. By deriving analytical expressions for interference patterns under both normal and oblique incidence conditions, we demonstrate that oblique incidence simplifies the interference behavior and allows the reliable extraction of transmittance values from maximum and minimum signal intensities. Using a 95 GHz CW oscillator (Model SFD-753114-103-10SF-P1, Eravant, Torrance, CA, USA) and a 1 mm-thick PET sample, we conducted transmission measurements while varying the detector position. The derived method enabled the calculation of interference-free transmittance values that were consistent across different sample positions. This approach offers a practical technique for material characterization, especially in applications such as nondestructive testing and plastic recycling.
Authors: Tomoaki Date, Seiya Miyazaki, Tadao Tanabe
Institution: Shibaura Institute of Technology
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
OpenAlex ID: W4414591900