Experimental measurement of absorptivity of sapphire at 532nm laser radiation

HE Guang-tao; WEI Xin; XIE Xiao-zhu; TAN Wei-min; SONG You-quan

doi:10.3969/j.issn.1001-3806.2011.01.016

In order to study the effects of the laser polarized direction and the incident angle on the laser reflectivity, transmissivity and absorptivity, the sapphire reflectivity, transmissivity and absorptivity at linearly-polarized 532nm laser beam were obtained by means of calorimetry. The obtained absorptivity was in good agreement with the one calculated with Fresnel formula. Experiment also examined the law of the sapphire reflectivity, transmissivity and absorptivity at different incident angle and polarization state. The experimental results have indicated that the reflectivity of linearly-polarized laser beam perpendicular to the incident plane increases with the incident angle. On the other hand the one parallel to the incident plane decreases gradually to the minimum till the incident angle close to 60, and then sharply increases. Under the radiation of parallel and perpendicular linearly-polarized laser beam the transmissivity decreases with the incident angle, while the absorptivity increases. It provides some references for the selection and optimization of technological parameters during the laser material processing.

Experimental measurement of absorptivity of sapphire at 532nm laser radiation

Corresponding author: WEI Xin, weixin@gdut.edu.cn;

1. Faculty of Electromechanical Engineering, Guangdong University of Technology, Guangzhou 510006, China;

2. Mechatronics and Information Engineering School, P'oshan University, Foshan 528000, China

Received Date: 2010-03-10

Accepted Date: 2010-04-15

Available Online: 2011-01-25

Abstract: In order to study the effects of the laser polarized direction and the incident angle on the laser reflectivity, transmissivity and absorptivity, the sapphire reflectivity, transmissivity and absorptivity at linearly-polarized 532nm laser beam were obtained by means of calorimetry. The obtained absorptivity was in good agreement with the one calculated with Fresnel formula. Experiment also examined the law of the sapphire reflectivity, transmissivity and absorptivity at different incident angle and polarization state. The experimental results have indicated that the reflectivity of linearly-polarized laser beam perpendicular to the incident plane increases with the incident angle. On the other hand the one parallel to the incident plane decreases gradually to the minimum till the incident angle close to 60, and then sharply increases. Under the radiation of parallel and perpendicular linearly-polarized laser beam the transmissivity decreases with the incident angle, while the absorptivity increases. It provides some references for the selection and optimization of technological parameters during the laser material processing.

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Reference (17)

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Experimental measurement of absorptivity of sapphire at 532nm laser radiation

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