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	A Conceptual Framework for the Automated Generalization of Geological Maps Based on Multiple Agents and Workflow 期刊论文 OAI收割 IEEE ACCESS, 2016, 卷号: 4, 页码: 6374-6385 作者: Zhang, Junqiang; Wu, Chonglong; Wang, Lizhe 收藏 \| 浏览/下载：25/0 \| 提交时间：2017/04/24 GEOMETRIC CALIBRATION SUBPIXEL CORRELATION IMAGING SATELLITES ORIENTATION MODELS
	Comparison and simulation of subpixel imaging modes for linear CCD (EI CONFERENCE) 会议论文 OAI收割 2012 3rd International Conference on Information Technology for Manufacturing Systems, ITMS 2012, September 8, 2012 - September 9, 2012, Qingdao, China 作者: Li Y.; He B.; Li Y.; Li Y.; Li Y. 收藏 \| 浏览/下载：45/0 \| 提交时间：2013/03/25 Subpixel technique of linear CCD is effective to enhance the spatial resolution without increasing the focal length of optics and reducing the pixel size. To compare image quality of two main subpixel imaging modes quincunx sampling and four-point sampling a method to quantitatively evaluate image quality of subpixel based on MTF was proposed. The MTF of quincunx and four-point sampling modes were derived. Analytical results shows that theoretical limiting resolution of quincunx sampling and four-point sampling is improved to 1.4 and 1.86 times respectively and MTF values at Nyquist frequency of two modes are increased by 0.1106 and 0.1679 respectively. MTFA in (0 0.5) of two subpixel imaging modes were calculated and results illustrates that four-point sampling offers much more improvement with image quality than quincunx sampling at the cost of double amount of data. A model for simulating subpixel imaging using Matlab was established and simulation results of spoke target verify the theoretical analysis. (2012) Trans Tech Publications Switzerland.
	Contrast research on interpolation and subpixel imaging in CCD geometric superresolution reconstruction (EI CONFERENCE) 会议论文 OAI收割 1st Asia Pacific Conference on Postgraduate Research in Microelectronics and Electronics, PrimeAsia 2009, November 19, 2009 - November 21, 2009, Shanghai, China 作者: Xu Y.-S.; Yang S.-W. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 In order to enhance the resolution of Charge Coupled Device (CCD) pixel with the pixel dimension and focal length of optical system unchanged the problem of CCD geometric superresolution is educed. The problem is discussed in terms of software and hardware. In software the bicubic interpolation is introduced while in hardware the subpixel imaging method is utilized. The subpixel imaging method integrates two uniform linear CCDs staggered by half dimension of pixel in one device. In operation the line frequency is doubled. At last the collected data is interweaved to synthesize a high resolution image. The two methods bicubic interpolation and subpixel imaging are simulated with Matlab7.0.1. The qualitative and quantitative analyses are given. The simulated results of lanczos and cubic spline interpolation methods are given simultaneously to show the performance of interpolation. The simulation result shows that the result images quality becomes better in both methods but compared with bicubic interpolation method the synthesized image PSNR gained from sub-pixel imaging is averagely enhanced by 2.1682dB while the elapsed time is reduced to be about one forth. The subpixel imaging method could significantly mitigate the image blur introduced by undersample. 2009 IEEE.
	Geometrical modulation transfer function of different active pixel of CMOS APS (EI CONFERENCE) 会议论文 OAI收割 2nd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 2, 2005 - November 5, 2005, Zian, China 作者: Li J.; Liu J.; Liu J.; Liu J.; Li J. 收藏 \| 浏览/下载：32/0 \| 提交时间：2013/03/25 The geometrical Modulation Transfer Function (MTF) of CMOS APS (active pixel sensor) is analyzed in this paper. Advanced APS have been designed and fabricated where different pixel shapes such as square rectangle and L shape were placed because the amplifier circuit and other function circuits inter pixel of APS take up some pixel area. MTF is an important figure of merit in focal plane array imaging sensors. Research on analyzing the MTF for the proper pixel shape is currently in progress for a centroidal configuration of a target position. MTF will give us a more complete understanding of the tradeoffs opposed by the different pixel designs and by the signal processing conditions. Based on image sensor sampling and reconstructing model the MTF expression of any active pixel shape has been deduced in this paper. According to actual pixel shape three different active area pixels were analyzed they were square rectangle and L shape their Fill Factor (FF) is 30% 44% and 55% respectively. Results of simulation experiments indicate that different pixel geometrical characteristics contribute significantly to the figures of their MTF. Different geometrical shape of active sensitive area of pixel and different station in pixel would influence MTF figures. The analysis results are important in designing better APS pixel and more important in analyzing imaging system performance of APS subpixel precision system.
	Self Imaging technique for refocusing an aerospace camera (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Devices and Instruments, August 21, 2005 - August 26, 2005, Changchun, China 作者: Li W.; Li W.; Wang X.; Wang X.; Wang X. 收藏 \| 浏览/下载：40/0 \| 提交时间：2013/03/25 A novel auto-focusing technique using a self imaging approach is developed for an aerospace camera having large aperture and long focus. Its optical system consists of an emitting system receiving system and two penta-prisms. Emitting system has three parts: a light source beamsplitter and aim slit. The receiving system includes a field lens two separate lenses and CCD. Using two little penta-prisms instead of a large planar mirror makes the autofocus system simple and compact. CCD was used as photoelectric converting device. A defocused signal is acquired by measuring the change of the two slit self-images position imaged on the CCD. A simple and compact construction of the auto-focusing system was proposed. The algorithm to calculate the moving of the slit-self images position was analyzed in order to achieve subpixel position estimation. The results of the experiments show a 10m focusing precision. The system demonstrates high resolution easy adjustment and high reliability.
	Subpixel imaging method with area-array CCD sensors and experiment 期刊论文 OAI收割 chinese science bulletin, 2000, 卷号: 45, 期号: 2, 页码: 137-139 作者: Liu, XP; Gao, Z; Deng, NM; Lu, Z; Wu, L 收藏 \| 浏览/下载：21/0 \| 提交时间：2015/11/09 subpixel imaging high resolution imaging CCD camera remote sensing