Development of one-pulse high-speed terahertz spectroscopic system

2022 Fiscal Year Final Research Report

• Project/Area Number: 18H03887
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Medium-sized Section 30:Applied physics and engineering and related fields
• Research Institution: Nagoya University
• Principal Investigator: Kawase Kodo 名古屋大学, 工学研究科, 教授 (00296013)
• Project Period (FY): 2018-04-01 – 2023-03-31
• Keywords: テラヘルツ波 / パラメトリック / 非線形光学 / 分光

Outline of Final Research Achievements

The only technology that can check for banned drugs hidden in mail or prescription drugs handed to you at the pharmacy without opening the package is the optical injection-type THz-wave parametric generator (is-TPG) that we are developing. However, the conventional is-TPG technique has problems of long inspection time and pulse-by-pulse output fluctuation due to the wavelength-sweeping spectroscopy. In this study, we have developed a one-pulse high-speed terahertz spectroscopy system that simultaneously generates multiple wavelengths by integrating the results of previous preliminary experiments at a high level, enabling real-time inspection of mail and prescription drugs, and total inspection of pharmaceutical tablets and powders in the manufacturing process, which have been expected for some time.

Free Research Field

テラヘルツ工学

Academic Significance and Societal Importance of the Research Achievements

is-TPGを用いたTHz分光器は、これまで不可能であった減衰が大きい厚手の遮蔽物内に隠された試薬の分光や、硬質プラスチック製品の3次元CTなども実現してきた。しかしながら、is-TPGは波長可変光源のため、ワンパルス毎に1波長しか出力できず、分光の際に波長を変える必要があり、測定時間が長くかかる。また、パルス毎の出力ゆらぎによって測定値がばらつくため、多数パルスの平均化を要する。このため、実用上求められる高速なリアルタイム測定が困難であった。本研究ではそのような課題を克服し、実用性の優れたテラヘルツ分光システムを実現した。