[21a-P06-1~4] 1.6 Ultrasonics

[21a-P06-3] Evaluation of absolute value of vibration displacement distribution using laser speckle and examination of laser pulse method

〇Yasuaki Watanabe¹, Jing Wang², Kengo Hara¹ (1.TMU, 2.Taiyo Yuden MT)

Keywords:laser speckle, polished measurement

The purpose of this study is to control the free angle of incidence on the polished surface with respect to the UV (ultraviolet) wavelength, which was difficult to obtain at that time (2004). We investigated the method of examining the reflectance of the polished surface and the laser speckle interferometry. Furthermore, the laser pulse method is used as the method used for laser speckle interference, but there is no method for accurately determining the relative angle and duty ratio of the laser beam. Therefore, we investigated the method of examining the reflectance of the mirror surface, the Laser speckle interferometry, and reported the concrete implementation of the laser pulse method.