Editor in chief:Jun-Hao CHU
International standard number:ISSN 1001-9014
Unified domestic issue:CN 31-1577
Domestic postal code:4-335
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Xu Jing;Chen XiaoShuang;Zhou Mei;Liu Wei
2005, 24(4):241-244.
Abstract:用FDTD方法计算了二维正方形复式晶胞光子晶体的光子特性.通过光子能带结构、光子态密度的分布以及沿ГX方向透射谱的计算,发现透射谱光子带隙的位置与能带结构符合得很好.光子态密度的分布也表明存在全带隙的光子频率范围,进一步研究给出这种结构光子晶体全带隙存在的物理起源.
Chen Lu;Wang YuanZhang;Wu Yan;Wu Jun;Yu MeiFang;Qiao YiMin;He Li
2005, 24(4):245-249.
Abstract:报道了用MBE的方法,在3英寸Si衬底上制备ZnTe/CdTe(211)B复合衬底材料的初步研究结果,该研究结果将能够直接应用于大面积Si基HgCdTe IRFPA材料的生长.经过Si(211)衬底低温表面处理、ZnTe低温成核、高温退火、高温ZnTe、CdTe层的生长研究,用MBE方法成功地获得了3英寸Si基ZnTe/CdTe(211)B复合衬底材料.CdTe厚度大于10μm,XRD FWHM平均值为120arc sec,最好达到100arc sec,无(133)孪晶和其他多晶晶向.
2005, 24(4):250-254.
Abstract:采用Sol-Gel方法,通过快速热处理,在Pt/Ti/SiO2/Si衬底上制备出Pb(Zrx,Ti1-x)O3成分梯度薄膜.经俄歇微探针能谱仪(AES)对制备的"上梯度"薄膜进行了成分深度分析,结果证实其成分梯度的存在.经XRD分析表明,制备的梯度薄膜为四方结构和三方结构的复合结构,但其晶面存在一定的结构畸变.经介电频谱测试表明,梯度薄膜的介电常数比每个单元的介电常数都大,但介电损耗相近.在10 kHz时,上、下梯度薄膜的介电常数分别为206和219.经不同偏压下电滞回线的测试表明,上、下梯度薄膜均表现出良好的铁电性质,其剩余极化强度Pr分别为24.3和26.8 μC·cm-2.经热释电性能测试表明,热释电系数随着温度的升高逐渐增加,室温下上、下梯度薄膜的热释电系数分别为5.78和4.61×10-8 C·cm-2K-1,高于每个单元的热释电系数.
Zhang TianXu;Dan Yan;Cao ZhiGuo
2005, 24(4):255-260.
Abstract:The property of spatial frequency of the nonuniformity noise in IRFPA was studied. And the conclusion is that low frequency noise generally dominates the inherent IRFPA nonuniformity noise. The experiment with real IRFPA data demonstrates the same conclusion. To avoid the disadvantage of the traditional spatial adaptive nonuniformity correction denoising the low frequency dominated nonuniformity noise, a feasible approach for nonuniformity correction of IRFPA, which integrates one-point correction with spatial adaptive correction scheme, was proposed in this study. Experiments show that the proposed scheme can achieve good performance when low frequency noise is dominant.
JIN Wei-Qi , WANG Chun-Yong , ZHANG Nan , WANG Ling-Xue , LU Ping
2005, 24(4):261-264.
Abstract:通过对垂直方向具有光学微扫描的288×4焦平面热成像过程的分析研究,提出了一种可实现亚像元成像处理算法,在垂直扫描的方向可使探测器传递函数的截止频率提高一倍,可明显改善系统成像质量和作用距离.算法简单,处理工作量小,易于实现实时处理.算法的实现对提高扫描型热成像系统的技术战术性能指标具有重要意义.
2005, 24(4):265-268.
Abstract:A reflecting FIR interferometer and measurement of electronic density in HL-2A tokamak were presented in this paper. The phase shift was calculated by a new kind of computer software compare technique. The way of self-fitting optical design was used to design the reflector in the chamber. To prevent the first mirror polluted, a special buffer was mount in the vacuum chamber and make the mirror work time longer. The results of measurement electron density show that the interaction between plasma and first wall is lower in diverter discharge than that in limit discharge.
Shen Yan;Zhang GuoQuan;Fu Bo;Xu QingJun;Xu JingJun
2005, 24(4):269-272.
Abstract:以双中心模型为基础,研究了同成份和近化学比掺铁铌酸锂晶体在稳态情况下的非挥发双色二步全息存储性能.通过比较在相同记录条件下同成份(锂的摩尔浓度为48.5%)与近化学比(锂的摩尔浓度为49.5%)掺铁铌酸锂的总空间电荷场的大小可以看到,在连续光所能达到的光强范围内,近化学比LiNbO3:Fe的总空间电荷场明显大干同成份LiNbO3:Fe的总空间电荷场.但是在高光强下,同成份与近化学比LiNbO3:Fe都可以达到10^6V/m量级的光致空间电荷场.
Sun Tao;Liang JinSui;Chen XingGuo;Hu XiaoNing;Li YanJin
2005, 24(4):273-276.
Abstract:The Hg_(1-x)Cd_xTe photovoltaic detectors with x=0.217 passivated by single ZnS layer ad dual (CdTe+ZnS) layers were fabricated in the same wafer. The fabricated devices were characterized by measurements of the diode low-frequency noise. The diode passivated by dual (CdTe+ZnS) layers show higher performance compared to diode passivated by the single ZnS layer at high reverse bias, and the modeling of diode dark current mechanisms indicate that the performance of the diode passivated by single ZnS is strongly affected by tunneling current related to the surface defects, which is responsible for the low frequency noise characteristics. By the analysis of X-ray reciprocal space map, it was found that the Q_y direction broadening of HgCdTe epitaxial layer passivated by ZnS was wider than the CdTe+ZnS, which confirmed the existence of defects in the surface of HgCdTe epitaxial layer passivated by ZnS.
Tong JinJun;Qiu KangMu;Li XiaoWen
2005, 24(4):277-280.
Abstract:The thermal infrared channels was in-flight calibrated by using surface temperature in Qinhai lake measured by auto buoy and atmospheric profile of NCEP reanalyzed data in Qinhai lake. The calibration results by using this method are consistent with those by using normal experiment method, which can in-flight calibrate the thermal infrared channels of satellite sensors constantly.
2005, 24(4):281-285.
Abstract:The traditional skeletonization algorithms based on distance transform can not guarantee the connectivity property,so saddle points should be added to solve the connectivity problem. However, these methods are complex and inaccurate,and saddle points can hardly be extended to 3D case. In this paper a novel method was presented, the skeleton obtained by growing from the skeleton seed with 1 pixel width restricted by distance transform, and the connectivity was assured by the growing process. Experiments show that the growing process is a skeleton evolvement from coarse to delicate, and the hierarchical skeleton can be easily achieved.
Tang ShiHao;Zhu QiJiang;Su LiHong
2005, 24(4):286-290.
Abstract:与可见光遥感不同,热红外传感器测得的辐射亮度值是温度和发射率的函数,因此,对于热红外遥感,温度和发射率的分离是一个关键问题?本研究从普朗克方程的维恩近似出发,定义并推导出与温度无关的ALPHA差值谱,并进一步提出消除维思近似影响的修正项.以此为基础,在不考虑大气下行辐射影响的条件下,借鉴ALPHA导出发射率法和ASTERTES算法的优点,提出一个新的发射率温度分离算法.与现有发射率温度分离算法相比,该算法的优点是原理清楚,流程简单,求解速度快,结果精度高,并且适用的温度和下垫面范围宽.
Fang Yong;Qi FeiHu;Pei BingZhe
2005, 24(4):291-295.
Abstract:The PCNN implementation and applications in image processing were discussed, For the specific implementation of PCNNs, a PCNN was forced to be a single pass network. And simplified model, look-up threshold table, and integer operation were used to decrease the time complexity. The time-index image and fingerprint time series were introduced into PCNNs, and a PCNN was combined with the traditional techniques of image processing for automatic image processing, e.g. image enhancement, edge detection, image segmentation and feature extraction, by the time-index image. The applied conditions are derived for perfect image processing, and a practical estimation of the linking coefficient is proposed, which helps to determine PCNN parameters directly.
Xu WeiDong;Yin Qiu;Kuang DingBo
2005, 24(4):296-300.
Abstract:Tree spectral match models including minimums distance (MD), spectral angel model (SAM), spectral correlation fitting (SCF), were calculated and analyzed based on the spectrums taken from the field. However, the difference of the three models is not significant. The SAM was better but far from the best. Under this circumstance, derivative method was used to enhance the ability of discrimination. The match models were recalculated after the first derivative. Better results are achieved and the discriminability is remarkably enhanced, especially to the minimums distance model.
Zhang XiYan;Liu QuanSheng;Wang XiaoChun;Bai ChaoHui;Lu LiPing;Xuan YiFang
2005, 24(4):301-303.
Abstract:Electron trapping infrared up-conversion material (CaS: Eu, Sm) was prepared with the carbon reducing method (CRM). The reaction mechanism, reducing principle, infrared upconversion mechanism and effect of calcined temperature on the lattice formation of CaS and its optical properties were studied. XRD patterns of the samples indicate that CaS: Eu, Sm is with face-center cubic structure. Excitation spectrum is within the range of 200~600nm. Fluorescence emission spectrum is a broadband spectrum peaking at 567nm, 606nm and 630nm respectively. The peak of the up-conversion emission luminescence spectrum is at 625nm. The wavelength response range of the up-conversion luminescence is located at 800~1600nm.
2005, 24(4):304-308.
Abstract:利用GMS-5多通道资料和MODTRAN辐射传输模式设计并实现了用卫星红外分裂窗通道反演大气可降水的物理反演算法.采用1998年夏季的资料进行了大气可降水反演试验,并使用探空资料对反演结果进行检验,其均方根误差为3.30mm.为了在业务上实现大气可降水物理反演算法,设计了通过利用GMS-5资料、数值预报资料以及RTTOV7快速辐射传输模式的反演大气可降水的物理算法,并用探空资料对反演结果进行检验,其均方根误差为4.09mm.结果表明:RTTOV7快速辐射传输模式的引入,使反演速度有显著的提高,能够满足业务要求.
2005, 24(4):309-311.
Abstract:The infrared radiation characteristic of the missile is an important parameter for evaluating the penetration ability of a missile. Measuring the infrared radiation characteristic is important for us to distinguish a warhead from multiple objects and warn. Studying the infrared radiation characteristic of target has military value. The infrared radiation characteristic of target and atmosphere transmissibility of infrared radiation were analysed, and the way of enhancing the detecting ability of the ground-based LW infrared radiation measuring equipment was discussed.
Yan ChengXin;Sang Nong;Zhang TianXu;Ceng Kun
2005, 24(4):312-316.
Abstract:Traditional transition region extraction methods are based on gradient operator. They are sensitive to noise and restricted by L_(low) and L_(high) . By analyzing properties of transition regions, a novel local complexity based on transition region extraction method (C-TREM) was presented. C-TREM is a direct method to extract transition regions. The filtering ability of local complexity improves the ability of C-TREM to deal with noises. C-TREM depends no more on L_(eow) and L_(high). Experimental results demonstrate that C-TREM significantly outperforms the conventional gradient-based transition region extraction methods (G-TREM)
2005, 24(4):317-320.
Abstract:Gyrotron oscillators with CW moderate power have an important foreground in the industrial field. In this study, a self-consistent nonlinear computation was carried out for a 28GHz CW technology gyrotron. The result shows that a 28GHz technology gyrotron operating at the TE02 mode and second harmonic can obtain an output power of 50kW and efficiency of 28% for beam current 6A and beam voltage 32kV.
Editor in chief:Jun-Hao CHU
International standard number:ISSN 1001-9014
Unified domestic issue:CN 31-1577
Domestic postal code:4-335