Laser light mask shape design and Analysis of laser power stability

• Main Authors: Yi-Lin Chiu, 邱奕霖
• Other Authors: 湯華興
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/dgdeqn

碩士 === 國立臺北科技大學 === 製造科技研究所 === 99 === The purpose of current study is to design a laser scanning system for a homemade rapid prototyping apparatus, to stabilize laser power, and to obtain a uniform energy of the laser beam by using a mask to modify the shape of laser beam. Laser was cooled with air and water, respectively, and laser power was measured by a power meter. After comparing the laser power stability obtained from those cooling system. The stability was measured with close-loop power control. The optimum stability was achieved by water cooling with close- loop power control. When scanning with a CO2 laser, the energy distribution is Gaussian function. To homogenize laser scanning, we expanded the laser beam, and modified the distribution by a mask. Eventually, the modified laser beam was focused on a working plane. Because all materials along the scanning path absorbed the same amount of energy, the bottom of the scanning path was flat rather than a Gaussian distribution.