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	Numerical analysis of residual stress evolution of AlSi10Mg manufactured by selective laser melting 期刊论文 OAI收割 OPTIK, 2017, 卷号: 137, 页码: 65-78 作者: Wu, Jiaojiao; Wang, Linzhi; An, Xuguang \| 收藏 \| 浏览/下载：20/0 \| 提交时间：2018/03/15 Selective laser melting Numerical simulation Laser exposure time Residual stress AlSi10Mg alloy
	Micro-motion exposure method based on PZT piezoelectric ceramics (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Material and Device Technology for Sensors, June 17, 2009 - June 19, 2009, Beijing, China 作者: Meng Z.; Meng Z. 收藏 \| 浏览/下载：100/0 \| 提交时间：2013/03/25 There mainly is laser digital photofinishing technique and digital photofinishing technique based on LCD consisting of TFT and LCOS in the digital photofinishing field at the present time. The former have a good many merit such as wide color gamut high processing rate large output size and high brightness but his cost is very high his maintain technique being comparatively complex that result in difficult use for people. The utilization ratio of the latter is low because of lower resolution and lower aperture ratio for LCD but the digital photofinishing based on LCD have lower cost and higher utilization ration being suitable for people's current standard of living. Considering above mentioned problem a micro-motion exposure method based on PZT piezoelectric ceramics used in digital image photofinishing is presented. The two-dimension micro-motion exposure system consisting of PZT piezoelectric ceramics LCD panel polarizing film and spring strip is designed. By means of PZT piezoelectric ceramics the LCD panel is removed about the one half of the pixel size of the LCD panel for four times from the original place at the same time imaging system is exposed four times at the printing paper. The software is used to control the time synchronization the exposure time and motion range of the LCD panel. The system has advantages such as shorter response time than 0.1seconds lesser motion error than 0.01 microns high stability and repeatability. Experimental results show that the proposed micro-motion exposure method improve the picture brightness and enlarge output size at the meantime reducing the cost of the system. 2009 SPIE.
	Key techniques of laser direct writing patterns on spherical substrate (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Design, Manufacturing, and Testing of Micro- and Nano-Optical Devices and Systems, July 8, 2007 - July 12, 2007, Chengdu, China 作者: Zhao J.-L.; Feng X.-G. 收藏 \| 浏览/下载：23/0 \| 提交时间：2013/03/25 Comparing with the writing method of plane pattern spherical pattern' has some remarkable different on several points. Firstly it is difficult to spin-coated a uniform photoresist film on a spherical substrate especially the ratio of spherical radius to caliber is smaller and the spin-coated way must match the ratio of spherical radius to caliber. Secondly if the sphere couldn't be regarded as a plane a so-called concentric optical scan movement way must be applied for the generation of spherical pattern because the reflex of substrate will affect the quantity of illumination. Commonly an alignment technique is indispensable with pattern generation of spherical surface by the concentric optical scan in order to ensure the orthogonal intersection of focusing laser beam and writing surface. Thirdly a uniform velocity control must be considered for the laser direct writing method on a spherical substrate. Otherwise the exposure time of photoresist will be different and the line widths of pattern will be also different at different areas. Fourthly commonly because the errors of concentric machine and substrate surface shape are bigger so focusing servo-control technique is also needful for writing a pattern on a spherical substrate. Focusing servo-control may keep the focal spot on the spherical surface by a focus detection and control system in the course of writing pattern. Using these techniques we fabricated a line width of 7m and a period of 600m isometric mesh on the concave of a spherical substrate.
	Key techniques of laser direct writing of fine lines on the spherical surface (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Design and Fabrication, August 21, 2005 - August 26, 2005, Changchun, China Liang F.; Hu J. 收藏 \| 浏览/下载：21/0 \| 提交时间：2013/03/25 The main principles of laser direct writing (LDW) system for lines on the spherical surface (SS) are discussed. It is pointed out that line profile is determined by the exposure dose distribution which lies on the light intensity distribution of focus plane and the scanning speed. To improve the quality of line profile on the SS several key techniques as follows are introduced. Firstly the unique system configuration four axes mutually intersecting at the center of the SS is adopted which ensures the shape of the focus be maintained circular during the writing period. Secondly an automatic focus system (AFS) with the function of automatic focus in a certain range is introduced. Thirdly to guarantee the linear velocity to accord with the exposure character of the photoresist all the time an efficient arithmetic that controls motors run at appropriate angular velocity in different latitude is developed. Finally to achieve a stable and well-behaved system so as to compensate the velocity instability resulting from unavoidable errors of mechanical and electronics factor a powerful programmable multi-axis controller (PMAC) is utilized as the kernel element of the servocontrol system and the curves of step response and parabolic response achieved by feedforward and PID loop tuning indicate that the location precision and velocity stability have reached a high level. The experimental results of LDW of lines on the SS work piece with a diameter 30 mm and a radius equal to 100 mm are given. The section analysis of the lines on the photoresist by the atomic force microscope (AFM) after exposure and development is performed. The results show that line width is about 3.0 m and the steep sides of the lines are parallel to each other.