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Design and simulation of CMOS star sensor lens with large relative aperture and wide field (EI CONFERENCE) 会议论文
2011 International Conference on Electronic and Mechanical Engineering and Information Technology, EMEIT 2011, August 12, 2011 - August 14, 2011, Harbin, China
Zhong X.; Jin G.
收藏  |  浏览/下载:57/0  |  提交时间:2013/03/25
A 50mm focal length  F/1.25  Gaussian type optical system is designed in this paper  which has 20field of view. Actual star image adding optical cross-talk effect of CMOS(Complementary Metal Oxide Semiconductor)  detector is simulated by non-sequential ray tracing in ZEMAX optical design and analysis software to evaluate its performance. The distortion relative to image spot centriod is introduced and calculated by simulated star images  which is less than 0.03% of lens in this paper. Thermal adaptability is discussed by opt-mechanic thermal analysis  which shows the RMS spot radius of marginal filed changes less than 0.7m under 10C temperature gradient  and changes less than 1m during homogeneous temperature changing from 40C to 40C. The results of analyses and simulations show the design of this lens can achieve the requirement of high precision CMOS star sensor well. 2011 IEEE.  
Design of driving circuit for binocular CCD image system (EI CONFERENCE) 会议论文
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optoelectronic Materials and Devices for Detector, Imager, Display, and Energy Conversion Technology, April 26, 2010 - April 29, 2010, Dalian, China
Zhang M.; Ren J.; Zhang X.
收藏  |  浏览/下载:29/0  |  提交时间:2013/03/25
The paper designs a driving circuit of high sensitive  wide dynamic and high signal-to-noise ratio for binocular CCD imaging system which adopts a Dalsa-made high resolution full-frame 33-mega pixels area CCD FTF5066M. Inner structure and driving timing of the FTF5066M sensor are presented. Field Programmable Gate Array (FPGA) is used as the main device to accomplish the timing design of the circuits and power driver control of the two sensors. By using the Correlated Double Sampling (CDS) technique  the video noise is reduced and the SNR of the system is increased. A 12- bit A/D converter is used to improve the image quality. The output rate of the imaging system designed with integrated chip can reach to 1.3 frames per second through bi-channel. For its good performance  low power consumption and small volume  the driving system can be applied to aeronautics and astronautics field. With a further improvement  a maximum data output rate of 2.7 frames per second can be reached through all the eight channels of the two CCDs. 2010 Copyright SPIE - The International Society for Optical Engineering.  
Study on the azimuth bearing scheme of a large Alt-azimuth telescope (EI CONFERENCE) 会议论文
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, April 26, 2010 - April 29, 2010, Dalian, China
Wang H.; Zhang J.; Dai S.
收藏  |  浏览/下载:32/0  |  提交时间:2013/03/25
The azimuth bearing schemes in typical large Alt-azimuth telescopes  especially the 3.5-m APO telescope and the 4.1-m SOAR telescope were analyzed. A scheme of high-angular contacted thrust ball bearing integrated with a radial ball bearing was put forward. According to the Hertz contact theory  the corresponding parameters were designed for engineering application. The static performance parameters  within the range of 60 85 original contact angle were calculated. Compared with the traditional plane thrust ball bearing  the results shows that the high-angular (80) contact thrust ball bearing has more benefits at bearing strength and rigidity for large telescope. The 1500mm diameter prototyping bearing shows good performance  including the axial jitter is 0.009mm  the radial jitter is 0.006mm  the maximum starting torque without load is 30N·m  and the load capacity is more than 30t  which offers advanced technique path for the buildup of the high precision azimuth shafting and the whole telescope system. 2010 Copyright SPIE - The International Society for Optical Engineering.  
Manufacture of 1.2m reaction bonded silicon carbide mirror blank CFID (EI CONFERENCE) 会议论文
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, April 26, 2010 - April 29, 2010, Dalian, China
Zhang G.; Zhao R.; Zhao W.; Bao J.
收藏  |  浏览/下载:18/0  |  提交时间:2013/03/25
Silicon carbide (SiC) is a new type candidate material for large-scale lightweight space mirror. Its low thermal distortion  high stiffness  fine optical quality and dimensional stability  make SiC an ideal material for large space born telescope. Since ten years Changchun institute optics  fine mechanics and physics (CIOMP) has developed reaction bonded SiC (RB-SiC) technology for space application  and can fabricate RB-SiC mirror with scale less than 1.0 meter for telescope. The green body is prepared with gel-casting method which is an attractive new ceramic forming process for making high-quality  complex-shaped ceramic parts. And then unmolding  drying  binder burning out  reacting bonded  the RB-SiC can be obtained. But with the development of space-born or ground telescope  the scale of primary mirror has exceeded 1.0 meter. So CIOMP has developed an assembly technique which called novel reaction-formed joint technology for larger RB-SiC mirror blank. The steps include joining of green bodies with mixture comprised of SiC particles and phenolic resin etc  firing  machining and sintering. Joining the 1.2 meter RB-SiC mirror blank by the novel reaction-formed joint technology. And testing the welding layer's performance  the results show that the thickness of 54-77m  the microstructure and thermal property can be comparable to the substrate and the mechanical property are excellent in bending strength of 307MPa. 2010 Copyright SPIE - The International Society for Optical Engineering.  
Model identification and closed-loop confirmation for opto-electronic platform of seeker (EI CONFERENCE) 会议论文
2010 2nd International Conference on Industrial Mechatronics and Automation, ICIMA 2010, May 30, 2010 - May 31, 2010, Wuhan, China
Liu H.; Liu B.; Chen J.; Jia H.; Zhang J.; Wang M.
收藏  |  浏览/下载:27/0  |  提交时间:2013/03/25
1D-KBA microscope using double-periodic multilayer (EI CONFERENCE) 会议论文
Advances in X-Ray/EUV Optics and Components IV, August 3, 2009 - August 5, 2009, San Diego, CA, United states
Mu B.; Wang Z.; Yi S.; Zhu J.; Wang X.; Jiang L.; Huang Q.; Bai Y.
收藏  |  浏览/下载:9/0  |  提交时间:2013/03/25
To study the action of shock wave in CH target  one-dimensional grazing incidence KBA microscope for 4.75keV energy was set up. Because of strong absorption in air  4.75keV energy microscope can just work in vacuum. Accordingly  the alignment and assemblage will be very complicated and difficult. A special multilayer method  using double periodic multilayer  was proposed to solve this problem. This multilayer has high reflectivity not only for 4.75keV X-rays but also for 8keV X-rays at the same grazing incidence angle. It means 1D-KBA microscope has the same light trace for different working energies. Therefore  we can implement the alignment and assembly of 4.75keV system by the help of 8keV X-rays. Because 8keV X-rays is very easy produced by X-ray tube and has strong transmittability in air  the alignment and assemblage process became relatively easy. By now  we have finished the alignment experiment at 8keV and obtained imaging results. The performance is about 2-3m resolution in 250m field of view. It is coincide with the calculation. 2009 SPIE.  
The synthesis and field emission property of carbon nanotubes on carbon fibers substrate (EI CONFERENCE) 会议论文
Technical Digest of the 20th International Vacuum Nanoelectronics Conference, IVNC 07, July 8, 2008 - July 12, 2008, Chicago, IL, United states
Leyong Z.; Weibiao W.; Jingqiu L.; Yuxue X.; Da L.; Song C.; Haifeng Z.
收藏  |  浏览/下载:22/0  |  提交时间:2013/03/25
Using ferrocene as catalyst precursor  C2H2 as carbon source  carbon nanotubes (CNTs) with uniform density were synthesized on carbon fibers substrate by floating catalyst method. The morphology and microstructure were characterized by field emission scanning electron microscope (FESEM) and high-resolution transmission electron microscopy (HRTEM). The observation showed that the length of CNTs is about 2 m  the average space between adjacent CNTs is about 300 nm and the diameter of CNT is about 45 nm. The less dense "short and stubby" aligned CNTs films should have good electron field emission characteristics. The results of field emission showed that the emission current of CNTs/carbon fibers was 5 A at the field of 2.5 V/m  and the emission current can be 280 A with a field of 7 V/m (the specimen area is 0.25 cm2 and the distance between cathode and anode is 200 m). The calculation based on the F-N plot indicated that the field enhancement factor of CNTs tip is 499122. Using the conductivity and chemical stability of carbon fibers and the uniform and sparse density distribution of CNTs on carbon fibers substrate  the tip predominance of carbon nanotubes can be exerted  and simultaneously the effect of screening effects between adjacent carbon nanotubes on the field emission performance can also be effectively decreased. The CNTs synthesized on carbon fibers substrate has many predominances for the fabrication of cold cathode devices. For example  using the removability of carbon fibers  the cathode of CNTs/carbon fibers can be arbitrarily moved  enlaced or combined to form different patterns  and the cathode of CNTs/carbon fibers can be also fabricated in large size. Therefore  CNTs/carbon fibers may have potential application in field emission displays.  
Large aperture low threshold current 980nmVCSELs fabricated with pulsed anodic oxidation (EI CONFERENCE) 会议论文
Optoelectronic Materials and Devices II, November 2, 2007 - November 5, 2007, Wuhan, China
Jinjiang C.; Yongqiang N.; Te L.; Guangyu L.; Yan Z.; Biao P.; Yanfang S.; Lijun W.
收藏  |  浏览/下载:19/0  |  提交时间:2013/03/25
Study of microsphere plate photomultiplier tube (EI CONFERENCE) 会议论文
ICO20: Remote Sensing and Infrared Devices and Systems, August 21, 2005 - August 26, 2005, Changchun, China
Wang G.; Duanmu Q.; Wang X.; Li Y.; Jiang D.; Wu K.; Tian J.
收藏  |  浏览/下载:23/0  |  提交时间:2013/03/25
The photomultiplier tube (PMT) that can work in different wavelength is an important detector device in remote sense technology. Microsphere plate using glass beads 50to 70m in diameter sintered together is the core component of the microsphere plate photomultiplier tube It is a novel two-dimension electron multiplier. The electrons gain for a single plate is about 1017 and do not have the phenomenon of ion-feedback. Furthermore the fabrication process is very easy. In this paper  much interest was put on the microsphere plate photomultiplier tube. Based on the analyses from the theory and the experiment result  we point out the key technology for fabricating PMT is how to obtain glass beads with narrow range in diameter and how to sinter the glass beads with a sufficient pylome. Factors affect the gradating technology and sintering process along with the solution to them is presented. In the last  the structure scheme and technological characteristic for fabricating microsphere plate photomultiplier tube were given. The pulse rising-time of MSP-PMT is below 400ps suitable to the detection of high-speed pulse. As easy to be fabricated and has great advantage over MCP multiplier in the ratio of performance to price  the microsphere plate photomultiplier tube is a promising dim-light detector.  
A new spaceborne compression approach for remote sensing imagery (EI CONFERENCE) 会议论文
ICO20: Remote Sensing and Infrared Devices and Systems, August 21, 2005 - August 26, 2005, Changchun, China
Xu X.; Dong G.; Feng Y.; Xu S.
收藏  |  浏览/下载:20/0  |  提交时间:2013/03/25
After analyzing advantages and disadvantages of these typical encoding methods: SPIHT and VQ  a "DWT+MRLE" approach for spaceborne data compression was proposed in this paper. This approach includes two steps: Discrete Wavelet Transform (DWT) and Modified Run Length Encoding (MRLE). The former used CDF9/7 biorthogonal wavelet filters to powerfully get rid of correlation between pixels in imagery. The later put enlightening information into the lowest bit of some key-position transform coefficients. Consequently  CDF9/7 and MRLE together make hardware platform remain high real-time capability  and help reconstructed images keep good fidelity with PSNR being about 40dB  compared with the original ones. Comparison between experimentations on SPOT4's low-spatial-resolution (10m) imagery and Ikonos2's high-spatial-resolution (1m) imagery  shows this "DWT+MRLE" method having better performance for remote-sensed imagery  especially those of higher resolution. Although inferior to 8:1  Compression Ration (CR) here near 5:1 is greater than France SPOT5's 3:1 and American Ikonos2's 11:2.6 on-board data compression. More important  this method having less computational amount is good for spaceborne capability of real time. The consumed time of different image size is also presented in this paper  based on TI TMSC6416 DSP chip with 600MHz CPU cycle clock.  


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