Development of a one-shot point diffraction interference microscope using a geometric phase shift

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K05311
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 30020:Optical engineering and photon science-related
• Research Institution: Osaka Prefecture University
• Principal Investigator: MIZUTANI Akio 大阪府立大学, 工学(系)研究科(研究院), 講師 (50400700)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 幾何学的位相 / 偏光カメラ / ワンショット位相分布測定

Outline of Final Research Achievements

A microscope that can observe the phase image of a transparent sample in real time has been developed. We introduced a geometric phase shift and a polarization camera to our developed point-diffraction interference microscope (PDIM) with a wire-grid polarization pinhole (WGP) in which the directions of metal wires are orthogonal to each other inside and outside the pinhole. The phase image can be taken at 60 fps, which is the frame rate of the polarization camera, and it is possible to observe at 12 fps when the phase image is calculated and displayed sequentially. We also examined the artifacts caused by the pixel arrangement of the polarization camera and showed that they can be reduced by the proposed appropriate weight distribution of 5x5 interpolation kernel.

Free Research Field

計測工学

Academic Significance and Societal Importance of the Research Achievements

本研究が他の定量位相顕微鏡と異なるのは，ワイヤーグリッド偏光ピンホール（WGP）のピンホール径がスポット径（エアリーディスク）程度の5マイクロメートルと小さいため，共通光路型で物体光と参照光を精度よく分離でき，その結果，正確な位相分布の測定が可能なことである．この顕微鏡がリアルタイム測定できるようになることで，病気による細胞の形態変化だけでなく，たとえば紫外線硬化樹脂の硬化過程の測定などの正確でリアルタイムの位相分布が必要な工業製品分野での応用が期待される．