Frequency Characteristics of Surface Wave Generated by Single-Line Pulsed Laser Beam with Two Kinds of Spatial Energy Profile Models: Gaussian and Square-Like

DOI QR코드

DOI QR Code

Seo, Ho-Geon;Kim, Myung-Hwan;Choi, Sung-Ho;Kim, Chung-Seok;Jhang, Kyung-Young

  • 투고 : 2012.06.19
  • 심사 : 2012.08.10
  • 발행 : 2012.08.30

초록

Using a single-line pulsed laser beam is well known as a useful noncontact method to generate a directional surface acoustic wave. In this method, different laser beam energy profiles produce different waveforms and frequency characteristics. In this paper, we considered two typical kinds of laser beam energy profiles, Gaussian and square-like, to find out a difference in the frequency characteristics. To achieve this, mathematical models were proposed first for Gaussian laser beam profile and square-like respectively, both of which depended on the laser beam width. To verify the theoretical models, experimental setups with a cylindrical lens and a line-slit mask were respectively designed to produce a line laser beam with Gaussian spatial energy profile and square-like. The frequency responses of the theoretical models showed good agreement with experimental results in terms of the existence of harmonic frequency components and the shift of the first peak frequencies to low.

키워드

Surface Wave;Laser-Ultrasound;Line Beam;Energy Profile;Gaussian;Square-Like

참고문헌

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피인용 문헌

  1. 1. Initial Second Harmonic Generation in Narrowband Surface Waves by Multi-Line Laser Beams for Two Kinds of Spatial Energy Profile Models: Gaussian and Square-Like vol.33, pp.3, 2013, doi:10.7779/JKSNT.2012.32.4.347

과제정보

연구 과제 주관 기관 : Korea Institute of Energy Technology Evaluation and Planning (KETEP)