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	The research of round raster readheads scheme (EI CONFERENCE) 会议论文 OAI收割 3rd international Conference on Manufacturing Science and Engineering, ICMSE 2012, March 27, 2012 - March 29, 2012, Xiamen, China Cong J.-F. 收藏 \| 浏览/下载：31/0 \| 提交时间：2013/03/25 The round raster is extensively applied in all kinds of high accuracy angular displacement measurement and control system. With the development of precise mechanotronics measuring instrument machining center CNC machine and various precise location testing technology a higher request is put forward to the accuracy and the function of raster measurement system. In this article it is concluded that double readheads is the most reasonable configuration scheme through tests of single readhead scheme two readheads and four readheads. (2012) Trans Tech Publications.
	High power VCSEL device with periodic gain active region (EI CONFERENCE) 会议论文 OAI收割 Optoelectronic Materials and Devices II, November 2, 2007 - November 5, 2007, Wuhan, China 作者: Zhang Y.; Liu Y.; Liu Y.; Liu Y.; Qin L. 收藏 \| 浏览/下载：31/0 \| 提交时间：2013/03/25 High power vertical cavity surface emitting lasers with large aperture have been fabricated through improving passivation lateral oxidation and heat dissipation techniques. Different from conventional three quantum well structure a periodic gain active region with nine quantum wells was incorporated into the VCSEL structure with which high efficiency and high power operation were expected. The nine quantum wells were divided into three groups with each of them located at the antinodes of the cavity to enhance the coupling between the optical field and the gain region. Large aperture and bottom-emitting configuration was used to improve the beam quality and the heat dissipation. A maximum output power of 1.4W was demonstrated at CW operation for a 400m-diameter device. The lasing wavelength shifted to 995.5nm with a FWHM of 2nm at a current of 4.8A due to the internal heating and the absence of active water cooling. A ring-shape farfield pattern was induced by the non-homogeneous lateral current distribution in large diameter device. The light intensity at the center of the ring increased with increasing current. A symmetric round light spot at the center and single transverse mode operation with a divergence angle of 16 were observed with current beyond 4.8A.
	Center-configuration selection technique for the reconfigurable modular robot 期刊论文 OAI收割 Science in China Series F: Information Sciences, 2007, 卷号: 50, 期号: 5, 页码: 697-710 作者: Liu JG(刘金国); Wang YC(王越超); Li B(李斌); Ma SG(马书根); Tan DL(谈大龙) 收藏 \| 浏览/下载：17/0 \| 提交时间：2012/05/29 reconfigurable robot modular robot center-configuration configuration network reconfiguration cost matrix center-configuration coefficient
	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.