รายละเอียดวารสารวิชาการ

  1. หน้าแรก
  2. รายชื่อนักวิจัย
  3. ฉัตรชัย พะวงษ์
  4. ข้อมูลวารสารวิชาการ

ชื่องานวิจัย ( Article Name)

Real-Time Double-Layer Thin Film Thickness Measurements Using Modified Sagnac Interferometer with Polarization Phase Shifting Approach

บทคัดย่อ ( Abstract )

This paper describes a modified Sagnac interferometer with a self-referenced polarization and phase-shifting technique for real-time thickness measurement of single- and double-layer transparent thin films. The proposed interferometric setup generated outstanding rotating linearly polarized light with a degree of polarization (DOP) of 99.40%. A beam splitter placed at the interferometer output separated the beam into two identical linearly polarized beams. One of the beams served as a reference, while the other served as a sensing arm. The output linear polarizer set at 45◦ relative to a reference plane was positioned anterior to the photodetectors to get rotating light intensities for phase shift measurement; hence, the intensities at various polarizations of 0◦ , 45◦ , and 90◦ were automatically acquired without any polarizing device adjustments. These intensities were then transformed into a phase retardation introduced by a sample, and the resulting phase shift was eventually converted into film thickness. The samples were properly prepared, with pure BK7 substrate being deposited by WO3-, Ta2O5-, and WO3/Ta2O5 films of known thicknesses. The thickness measurement obtained from the proposed system yielded reading errors of 1.3%, 0.2%, and 1.3/2.5% for WO3-, Ta2O5-, and WO3/Ta2O5 films, respectively. The mathematical theory was effectively demonstrated and empirically confirmed. The experimental results show that the proposed setup has a lot of potential for real-time, non-destructive thickness assessment of transparent thin films without the need to modify polarizing device orientations.

เอกสารวิจัย ( Paper )

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ผู้เขียน ( Authors )

  • ฉัตรชัย พะวงษ์

ข้อมูลการเผยแพร่ ( Journal Infomation )