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Updated: Jul 7, 2026
11:34
Subsurface Defect Localization by Structured Heating Using Laser Projected Photothermal Thermography
Published on: May 15, 2017
Detection of photothermal effect by laser speckle strain gauge
Applied Optics
|May 1, 1997
Abstract:
A new method for simple and sensitive detection of photothermal strain caused by laser irradiation of plastic plates has been proposed. In-plane strain of the surface is detected directly by optoelectronic detection of speckle displacements at two symmetrical positions about a probe beam. The initial bending of the plate owing to the temperature gradient along the plate thickness is measured and shows good agreement with one-dimensional calculations.
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