Study of Microscopy with Pseudo-comb Interfermetry and high-speed discrete-frequency scanning laser

2018 Fiscal Year Final Research Report

• Project/Area Number: 16H03879
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Optical engineering, Photon science
• Research Institution: Saitama University
• Principal Investigator: SHIODA Tatsutoshi 埼玉大学, 理工学研究科, 准教授 (10376858)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 光学干渉 / 表面形状計測 / 離散波長可変レーザー / コム干渉 / インライン全数検査

Outline of Final Research Achievements

The technology for the inspection of the surface profilometry of the product in the manufacturing field was studied. A two-dimensional single-shot miscroscopy, which can measure the distance in the millimeter region with micrometer resolution in the depth direction, was constructed as non-contact measurement using an optical interferometer.Single-shot two-dimensional tomographic images obtained by high-order pseudo-optical comb interference fringes were observed by a CCD with a high volume sampling rate, using an optical comb that can be easily generated as a light source. On the other hand, the fundamental technology of pseudo optical comb interference was developed by developing an ultra-high-speed optical frequency scanning repetition (1 MHz). The repetition rate is faster than the imaging time of CCD and a high-speed discrete wavelength tunable laser, which performs frequency scanning discretely (200 GHz interval) as the light source.

Free Research Field

光計測

Academic Significance and Societal Importance of the Research Achievements

離散的な波長可変レーザーは、比較的簡便に低コストで作成できる。その上、スキャン速度より遅い検出器で観測することで、光コムと同様の干渉計測信号を得ることができるため、低コストで高感度な計測を実現できる可能性を持つ。さらに、シングルショットで2次元断面形状を計測する光学システムは、振動環境下においても物体のマイクロメートル精度での表面検査などを行うことができ、モノづくりの信頼性を飛躍的に向上できる。