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	Research of ballistic missile early warning system (EI CONFERENCE) 会议论文 OAI收割 2nd International Conference on Advanced Engineering Materials and Technology, AEMT 2012, July 6, 2012 - July 8, 2012, Zhuhai, China Zhang M.-H.; Zhang Y.-Y. 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 To develop a lift early warning infrared device as a part of land or boat (ship) early warning system the system has the ability to target pre-discovery and instructions invasion. Methods: In support of distant air situation alerts the enemy aircraft missiles and other long-range goals obtain the target type and preliminary judgment of grade deliver the alarm information to the command system. The infrared alarm device detects the target's own infrared radiation passively alarms the incoming targets at low altitude and low altitude remote when radar and other equipment is out of work. Results: The accuracy of entire system reached 20 according the analysis. Conclusions: The device has a full range of complex background with high sensitivity high resolution anti-jamming fast response time and other characteristics. (2012) Trans Tech Publications Switzerland.
	Multi-parameters decoupling method with Lamb wave sensor for improving the selectivity of label-free liquid detection (EI CONFERENCE) 会议论文 OAI收割 2011 16th International Solid-State Sensors, Actuators and Microsystems Conference, TRANSDUCERS'11, June 5, 2011 - June 9, 2011, Beijing, China 作者: Zhou L. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 The anti-symmetric modes (A01 mode for low frequency A 03 mode for high frequency) and symmetric modes (S0 mode) produced by Lamb wave sensor are used to detect multi-parameters of a liquid such as its density sound velocity and viscosity. These modes are found to be very different to the parameters. For example the A01 mode is very sensitive to the liquid's density but the A03 mode is sensitive to its sound velocity. The measurements of the attenuation with S0 mode can give out liquid's viscosity after its density been determined by A 01 mode. That could be a way to distinguish an unknown liquid with high sensitivity or to solve the problem of the selectivity of label free detection on biosensors. 2011 IEEE.
	The Research of real time auto-recognition of the moire fringe (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Imaging Detectors and Applications, May 24, 2011 - May 26, 2011, Beijing, China Wang M.-J.; Wu Z.-G. 收藏 \| 浏览/下载：19/0 \| 提交时间：2013/03/25 Measuring the movement of raster by the method of moire fringe has the advantage of high sensitivity high resolution and non-contacted measurement. The characteristic of moire fringe is that the image is white alternate with black the angle of the stripes is uniform the width of the stripes is uniform the terminators of the stripes aren't clear. A fast method that can figure out the width and angle of the moire fringe precisely is put forward in this paper. It calculates the angle the stripes firstly. According to the principle of the minimum mean squared error (MMSE) the closer a series of data is the smaller the value of the MMSE will be. The method is described as follows: It takes the image's center as the origin 180 beelines pass through the origin with the same angle interval. it calculates the value of the minimum mean squared error of the 180 beelines and find out the least one among those then the angle of the moire fringe comes out primarily. In order to improving the calculating precision of moire fringe 60 equal angles are divided in the neighborhood of the angle then a precise angle of moire fringe is calculated according to the principle of the MMSE. After getting out the angle of the moire fringe we begin to calculate the width of moire fringe. A line vertical with the moire fringe is drawn and we can get the width of the moire fringe by the vertical line. In order to get over the influence of the noise an effective area with the shape of diamond is selected in the image. The data of area is accumulated and projected according to the direction of moire fringe and a sine curve come out. The width of moire fringe can be obtained by getting the position of the first wave crest the position of the last wave crest and the number of wave crest. Experiments prove that the precision of the method put forward in this paper is enhanced in comparison with the traditional frequency method the precision of width calculation achieves to 99.6% according to the evaluation indicators of width detection error. The computing speed is boosted largely compared with traditional method and it can achieve with 15 ms that satisfying the demand of real time. 2011 SPIE.
	Study on sensing properties of a temperature-independent high pressure sensor base on tapered FBG (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photonics and Optoelectronics, SOPO 2010, June 19, 2010 - June 21, 2010, Chengdu, China 作者: Liu Y.; Zhang Y.; Zhang X. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 The sensing properties with strain and temperature of tapered FBG had been researched both theoretically and experimentally. Based on tapered FBG and thin-wall strain cylinder structure a novel temperature-independent high pressure sensor was fabricated and investigated. The tapered FBG performed as a chirped grating whose bandwidth and reflection power broadened and increased when the pressure applied on it. Moreover the bandwidth and the reflection power were temperature-independent. So the value of the strain can be obtained by detecting the reflection power. This method effectively solved the cross-sensitivity problem. The experiment results indicated that this sensor provided a measurement range of 040MPa with a sensitivity of 0.04w/MPa low cost and good application prospect. 2010 IEEE.
	Measuring instrument for radial composite deviations of high-precision master gear (EI CONFERENCE) 会议论文 OAI收割 6th International Symposium on Precision Engineering Measurements and Instrumentation, August 8, 2010 - August 11, 2010, Hangzhou, China 作者: Zhang Y.; Wang L.; Wang L.; Wang L. 收藏 \| 浏览/下载：37/0 \| 提交时间：2013/03/25 During double flank rolling composite detection the radial composite deviations of master gears has been existed and transferred to the measured gear by the primary harmonic curve. In order to improve measurement accuracy a measuring instrument is developed for radial composite deviations of high-precision master gear in the paper. This instrument uses the structure of spring-suspend swing span to overcome the shortcomings of large rotation errors low sensitivity low resolution and large measuring force appearing in the traditional combination-type gear inspection instrument. Artificial intelligence technology is used to improve the efficiency and accuracy of this instrument. The result is that the measuring apparatus is able to meet the requirement and improve efficiency through the measuring experiments on master gears of precision grade 2 with modulus 2 mm and 3 mm respectively. 2010 SPIE.
	Temperature characteristics of high power vertical cavity surface emitting lasers (EI CONFERENCE) 会议论文 OAI收割 Semiconductor Lasers and Applications III, November 12, 2007 - November 13, 2007, Beijing, China 作者: Qin L. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 By using oxidation confinement technology high power vertical-cavity surface-emitting lasers are fabricated in experiment. The electrical and optical performance characteristics such as threshold current efficiency emission wavelength and output power are measured under continuous wave (CW) condition at room temperature. The maximum output power is up to watt regime at wavelength of about 980nm. The temperature characteristics of the device are investigated experimentally in detail. The variation in lasing threshold current with temperature is studied. The characteristic temperature T0 of the device is derived and the value is about 211K. Such a high characteristic temperature T0 of threshold current can lead to good temperature sensitivity of the device. At the same time the lasing spectrum characteristics with temperature are also measured. The wavelength shift with temperature is just about 0.06nm/K. From the measured results it is shown that the device can still operate at high temperature condition.
	Design of dual-FOV refractive/diffractive LWIR optical system (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Advanced Optical Manufacturing Technologies, July 8, 2007 - July 12, 2007, Chengdu, China 作者: Wang L.-J.; Zhang J.-P.; Wang L.-J.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：33/0 \| 提交时间：2013/03/25 An infrared-optical zoom system using binary element is proposed in this paper. The two main advantages of the zoom system introducing here are: bigger F-number and lower cost. The primary optical properties are: F/#=1 Second Others zoom ratio =1:4 binary element is used to correct the chromatical aberration by taking the advantage of negative dispersion characteristics and the cost of the system is lower than that of conventional ones with Zinc Selenide (Znse) material at the same level. In the binary element is rotational symmetric with one step which is easy to fabricate in order to balance 5th spherical aberration and dual field are 26.6 and 5.6respectively. Wider field of view is used for search and the smaller one is used for imaging details. This system uses un-cooled infrared detector with 320240 pixels and 45m pixel size. The F-number matches the sensitivity range of the detector array. Three aspects are considered during design process to make the system more satisfactory and more achievable. First 5th coma aberration and 5th astigmatic aberration the manner of zoom is accomplished by exchanging tow lenses into the smaller field of view system layout. The lens exchange manner faces the requirement of simple system structure and good image quality in both focal points. It can also make the system more feasible in the alignment process than mechanical-zooming manner and optical-zooming manner high-order asphere surfaces with 2th order to 10 th order are also hired in the system. Asphere surface is useful in compressing the system and improving optical system transmittance. This kind asphere surface is on industrial level featuring low cost and easy to fabricate. It is shown that good image quality can achieved by implementing five Germanium lenses and the transmittance of system is 72%. All aberrations are diffraction-limited both spherical aberration and astigmatic aberration are corrected. When the field of view(FOV) is 26.6 and the focal length is 152mm MTF at Nyquist frequency(11lp/mm) is great than 0.7. The spherical aberration is -0.0073. The coma aberration is 0.0978 and the astigmatic aberration is -0.013. When the field of view(FOV) is 5.6 and the focal length is 38mm MTF at Nyquist frequency is great than 0.8 with spherical aberration -0.0046 the coma aberration 0.055 and astigmatic aberration 0.034.