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	In Situ 3D Segmentation of Individual Plant Leaves Using a RGB-D Camera for Agricultural Automation 期刊论文 OAI收割 SENSORS, 2015, 卷号: 15, 期号: 8, 页码: 20463-20479 作者: Xia, CL; Wang, LT; Chung, BK; Lee, JM 收藏 \| 浏览/下载：45/0 \| 提交时间：2016/04/24 plant monitoring occlusions leaf detection mean shift center of divergence automatic initialization
	Modeling and analysis of dialyte-lens auto-focusing technology for theodolite (EI CONFERENCE) 会议论文 OAI收割 2008 International Conference on Optical Instruments and Technology: Optoelectronic Measurement Technology and Applications, November 16, 2008 - November 19, 2008, Beijing, China Wu L.-T.; Qiao Y.-F.; Wu D.-K.; Cai S. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 In order to realize real-time auto-focusing for theodolite lens-apart method was designed with the corresponding math model built and analyzed. An Object beam splitted after the first image surface of the theodolite traveled through two dialyte lens and then was imaged on CCD. The distance between two spots when exactly focused was set as the calibration value and the relationship between defocus distance and spot offset was given. The influence of tracking center shift and divergence angle etc. on focusing accuracy was analyzed. Compared with the traditional focusing method this scheme has a higher accuracy faster calculation higher tolerance for environment temperature and a simpler construction. The experiment result exhibited a resolution higher than 0.056mm which shows a bright engineering application prospect for this method. 2009 SPIE.
	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：33/0 \| 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.
	High-power InGaAs/GaAs VCSEL's two-dimension arrays (EI CONFERENCE) 会议论文 OAI收割 ICO20: Lasers and Laser Technologies, August 21, 2005 - August 26, 2005, Changchun, China 作者: Liu Y.; Wang L.-J.; Wang L.-J.; Liu Y.; Liu Y. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 Selectively oxidized InGaAs/GaAs vertical -cavity surface-emitting lasers (VCSEL) array at an emission wavelength of 980nm was reported. A 16 elements array with 200m aperture size (250m center spacing) of individual elements shows a CW output power of 1.21 W at room temperature resulting in 1 KW/cm2 average optical power density. The device threshold current is 1.32A The lasing peak wavelength is 981.9 nm the full width at half-maximum is 0.7 nm and the far-field divergence angle is about 17.The characteristics of a single device with a active region diameter of 800m is compared with that of a 2-D array with active region diameter of individual clement of 200m. These two kinds of devices have the same total lasing area. At the same current injection the single device has a higher threshold and a higher output power than the array. The red shift of single device is more obvious than that of the array's.