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	Research on automatic Hartmann test of membrane mirror (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, April 26, 2010 - April 29, 2010, Dalian, China 作者: Zhang P. 收藏 \| 浏览/下载：31/0 \| 提交时间：2013/03/25 Electrostatic membrane mirror is ultra-lightweight and easy to acquire a large diameter comparing with traditional optical elements so its development and usage is the trend of future large mirrors. In order to research the control method of the static stretching membrane mirror the surface configuration must be tested. However membrane mirror's shape is always changed by variable voltages on the electrodes and the optical properties of membrane materials using in our experiment are poor so it is difficult to test membrane mirror by interferometer and null compensator method. To solve this problem an automatic optical test procedure for membrane mirror is designed based on Hartmann screen method. The optical path includes point light source CCD camera splitter and diffuse transmittance screen. The spots' positions on the diffuse transmittance screen are pictured by CCD camera connected with computer and image segmentation and centroid solving is auto processed. The CCD camera's lens distortion is measured and fixing coefficients are given to eliminate the spots' positions recording error caused by lens distortion. To process the low sampling Hartmann test results Zernike polynomial fitting method is applied to smooth the wave front. So low frequency error of the membrane mirror can be measured then. Errors affecting the test accuracy are also analyzed in this paper. The method proposed in this paper provides a reference for surface shape detection in membrane mirror research. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Electro-optic integration of embedded electrodes and waveguides in LiNbO3 using a femtosecond laser 期刊论文 OAI收割 opt. lett., 2008, 卷号: 33, 期号: 19, 页码: 2281, 2283 Liao Yang; Xu Jian; 程亚; Zhou Zenghui; He Fei; Sun Haiyi; Song Juan; Wang Xinshun; 徐至展; Sugioka Koji; Midorikawa Katsumi 收藏 \| 浏览/下载：950/56 \| 提交时间：2009/09/18 Embedded electrodes Femtosecond laser ablations Femtosecond lasers Interaction lengths New opportunities Optic devices Optical modulators Wave voltages
	Low drive-voltage and high-bandwidth electro-optic modulators based on BaTiO3 thin-film waveguides (EI CONFERENCE) 会议论文 OAI收割 Science and Technology of Dielectrics for Active and Passive Photonic Devices - 210th Electrochemical Society Meeting, October 29, 2006 - November 3, 2006, Cancun, Mexico Sun D. G.; Fu X. H.; Liu Z. F.; Ho S. T.; Wessels B. W. 收藏 \| 浏览/下载：45/0 \| 提交时间：2013/03/25 We investigated electro-optic modulator structures to target low drive voltage high-speed modulation and small device size with c-axis grown BaTiO3/MgO ferro-electric thin films. In this study the calculations are focused on the ideal thin film with a quadratic relation between the half-wave drive voltage V and the interaction length L in the electro-optic modulation case we obtained in previous work. With the quadratic electro-optic modulating relation and the optimal rib waveguide structure of BaTiO3/MgO thin films the frequency-voltage-size performances for 2.5GHz 10GHz 40GHz and 100GHz modulation bandwidths have been obtained under half-wave drive voltages of 0.8V 1.6V 3.0V and 4.8V respectively for the ideal film with r51=730 pm/V at 1550nm wavelength where both the phase velocity matching condition and the conductor induced microwave attenuation are considered. The required device lengths to achieve these four typical values of modulation bandwidth are 3.3 mm 0.8 mm 0.4 mm and 0.2 mm respectively. With the c-axis grown BaTiO3/MgO crystal thin films and the quadratic electro-optic modulating relation an electro-optic coefficient of reff=180 pm/V for the c-axis grown BaTiO3/MgO ferro-electric thin films was measured which is relatively far from the ideal value of r51=560 pm/V. copyright The Electrochemical Society.