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Contents
2005
Volume: 24 Issue 4
18 Article(s)
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Research Article
NUMERICAL STUDY ON PHOTONIC PROPERTIES IN TWO-DIMENSIONAL COMPLEX PHOTONIC CRYSTALS OF SQUARE LATTICE
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]
The photonic properties of a two-dimensional complex photonic crystal (PC) of square lattice were calculated by finite different time domain (FDTD) method. The photonic band structure, photonic density of states, the transmission and reflection coefficients along ГX direction were obtained. The results indicate a clearThe photonic properties of a two-dimensional complex photonic crystal (PC) of square lattice were calculated by finite different time domain (FDTD) method. The photonic band structure, photonic density of states, the transmission and reflection coefficients along ГX direction were obtained. The results indicate a clear correspondence between the photonic band structure and the transmission spectra along ГX direction. The photonic band structure was also shown by the photonic density of states. Furthermore, the theoretical explanation for the opening of the band gap was given..
Journal of Infrared and Millimeter Waves
- Publication Date: Aug. 01, 2005
- Vol. 24, Issue 4, 241 (2005)
MOLECULAR BEAM EPITAXIAL GROWTH OF CdTe(211)B COMPOSITE SUBSTRATES ON SILICON
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
The preliminary results on molecular beam epitaxial growth of ZnTe/CdTe(211)B composite substrates on silicon for HgCdTe FPAs applications were described. Si/ZnTe/CdTe(211)B composite substrate on 3-inch Si was obtained by the improvements in low temperature treatment on Si(211), low temperature ZnTe nucleation, high tThe preliminary results on molecular beam epitaxial growth of ZnTe/CdTe(211)B composite substrates on silicon for HgCdTe FPAs applications were described. Si/ZnTe/CdTe(211)B composite substrate on 3-inch Si was obtained by the improvements in low temperature treatment on Si(211), low temperature ZnTe nucleation, high temperature annealing as well as high temperature ZnTe or CdTe growth. (133) twin-free CdTe (211)B layers were obtained. The CdTe thickness was larger than 10 μm. An averaged XRD FWHM of 120 arc sec with a minimum value of 100 arc sec was achieved..
Journal of Infrared and Millimeter Waves
- Publication Date: Aug. 01, 2005
- Vol. 24, Issue 4, 245 (2005)
PREPARATION, STRUCTURE AND CHARACTERISTICS ON COMPOSITIONALLY GRADED Pb(Zrx,Ti1-x)O3 FERROELECTRIC THIN FILMS
[in Chinese], and [in Chinese]
Compositionally graded Pb(Zrx,Ti1-x)O3 thin films were prepared on platinum-coated silicon substrates by Sol-Gel method and rapid heat-treatment. The composition depth profile of a typical up-graded film was determined by using a combination of auger electron spectroscopy and Ar ion etching. The results confirm that thCompositionally graded Pb(Zrx,Ti1-x)O3 thin films were prepared on platinum-coated silicon substrates by Sol-Gel method and rapid heat-treatment. The composition depth profile of a typical up-graded film was determined by using a combination of auger electron spectroscopy and Ar ion etching. The results confirm that the processing method produces graded composition change. XRD analysis shows that the graded thin films possess the structure of tetragonal and rhombohedral. The dielectric constant of the graded thin films is higher than that of each thin film unit, but dielectric loss is near to each other. The dielectric constants of up-graded and down-graded thin films are 206 and 219 at 10 kHz, respectively. The hysteresis loops of the graded thin films show fine ferroelectric properties. The remanent polarizations of up-graded and down-graded thin films are 24.3 and 26.8 μC·cm~(-2), respectively. The pyroelectric coefficient of the graded thin films gradually increases with the temperature up, and is higher than that of each thin film unit. The pyroelectric coefficients of up-graded and down-graded thin films are 5. 78 and 4. 61 ×10 -8 C·cm-2 K-1 at room temperature, respectively..
Journal of Infrared and Millimeter Waves
- Publication Date: Aug. 01, 2005
- Vol. 24, Issue 4, 250 (2005)
STUDY ON THE PROPERTY OF SPATIAL FREQUENCY OF NONUNIFORMITY NOISE IN IRFPA AND THE IMPROVEMENT OF SPATIAL ADAPTIVE NONUNIFORMITY CORRECTION TECHNIQUE
[in Chinese], [in Chinese], and [in Chinese]
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 adaptivThe 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..
Journal of Infrared and Millimeter Waves
- Publication Date: Aug. 01, 2005
- Vol. 24, Issue 4, 255 (2005)
STUDY ON SUB-PIXEL PROCESSING ALGORITHM FOR SCANNING FPA THERMAL IMAGING SYSTEM
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
Based on an analysis of imaging process of 288×4 FPA (Focal Plane Array) thermal imaging system with vertical micro-scanning, a processing algorithm for realizing sub-pixel imaging was proposed. The method doubles the cut-off frequency in vertical MTF (Modulate Transfer Function) of the detector, and markedly imprBased on an analysis of imaging process of 288×4 FPA (Focal Plane Array) thermal imaging system with vertical micro-scanning, a processing algorithm for realizing sub-pixel imaging was proposed. The method doubles the cut-off frequency in vertical MTF (Modulate Transfer Function) of the detector, and markedly improves the system imaging quality and action range. The algorithm is simple, the amount of treatment is small, and a real time processing is easily achieved. The realization of this algorithm has great significance in improving technological tactic performance of thermal imaging systems..
Journal of Infrared and Millimeter Waves
- Publication Date: Aug. 01, 2005
- Vol. 24, Issue 4, 261 (2005)
DESIGN AND APPLICATION OF REFLECTING FIR INTERFEROMETER
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
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 poA 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..
Journal of Infrared and Millimeter Waves
- Publication Date: Aug. 01, 2005
- Vol. 24, Issue 4, 265 (2005)
STUDIES ON NONVOLATILE HOLOGRAPHIC RECORDING FOR LiNbO3:Fe WITH DIFFERENT STOICHIOMETRY
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
The steady-state nonvolatile two-step, two-color holographic recording performance for both the congruent and the near-stoichiometric LiNbO3:Fe was studied theoretically based on the two-center model. It is shown that the nonvolatile two-step, two-color holography performance in the near-stoichiometric LiNbO3:Fe is mucThe steady-state nonvolatile two-step, two-color holographic recording performance for both the congruent and the near-stoichiometric LiNbO3:Fe was studied theoretically based on the two-center model. It is shown that the nonvolatile two-step, two-color holography performance in the near-stoichiometric LiNbO3:Fe is much better than that in the congruent LiNbO3:Fe within the intensity range reachable by the continuous-wave lights. In addition, it is shown that a light-induced space charge field of the order of 10~6 V/m is achievable in both the near-stoichiometric and the congruent LiNbO3:Fe with high intensities..
Journal of Infrared and Millimeter Waves
- Publication Date: Aug. 01, 2005
- Vol. 24, Issue 4, 269 (2005)
LOW-FREQUENCY NOISE OF Hg1-xCdxTe LONG-WAVE PHOTOVOLTAIC DETECTOR
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
The Hg1-xCdxTe 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 diThe Hg1-xCdxTe 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..
Journal of Infrared and Millimeter Waves
- Publication Date: Aug. 01, 2005
- Vol. 24, Issue 4, 273 (2005)
NEW METHOD OF IN-FLIGHT ABSOLUTE CALIBRATION FOR THERMAL INFRARED CHANNALS OF SATELLITE SENSORS
[in Chinese], [in Chinese], and [in Chinese]
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 calibrateThe 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..
Journal of Infrared and Millimeter Waves
- Publication Date: Aug. 01, 2005
- Vol. 24, Issue 4, 277 (2005)
HIERARCHICAL CONNECTED SKELETONIZATION ALGORITHM BASED ON DISTANCE TRANSFORM
[in Chinese], [in Chinese], and [in Chinese]
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 wasThe 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..
Journal of Infrared and Millimeter Waves
- Publication Date: Aug. 01, 2005
- Vol. 24, Issue 4, 281 (2005)
THERMAL INFRARED TES ALGORITHM BASED ON CORRECTED ALPHA DIFFERENCE SPECTRUM
[in Chinese], [in Chinese], and [in Chinese]
Different from visible spectral remote sensing, thermal infrared radiances vary with both temperature and emissivity. Hence, for thermal infrared remote sensing, the separation of temperature and emissivity is a key problem. In this study, by starting from WIEN’s approximation, ALPHA difference spectrum was defined andDifferent from visible spectral remote sensing, thermal infrared radiances vary with both temperature and emissivity. Hence, for thermal infrared remote sensing, the separation of temperature and emissivity is a key problem. In this study, by starting from WIEN’s approximation, ALPHA difference spectrum was defined and derived which is independent of temperature. Then, a correction item to remove the influence of WIEN’s approximation on ALPHA difference spectrum was developed. On these bases, a new temperature and emissivity separation algorithm was developed under the condition of neglecting the effect of atmosphere downwelling radiation, which combines attractive features of ALPHA derived emissivity method and ASTER TES algorithm. Compared with current TES algorithm, the new algorithm is fast, simple and precise. It can be used for wide temperature and surface type ranges..
Journal of Infrared and Millimeter Waves
- Publication Date: Aug. 01, 2005
- Vol. 24, Issue 4, 286 (2005)
PCNN IMPLEMENTATION AND APPLICATIONS IN IMAGE PROCESSING
[in Chinese], [in Chinese], and [in Chinese]
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 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..
Journal of Infrared and Millimeter Waves
- Publication Date: Aug. 01, 2005
- Vol. 24, Issue 4, 291 (2005)
COMPARISON OF DIFFERENT SPECTRAL MATCH MODELS
[in Chinese], [in Chinese], and [in Chinese]
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 circTree 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..
Journal of Infrared and Millimeter Waves
- Publication Date: Aug. 01, 2005
- Vol. 24, Issue 4, 296 (2005)
PREPARATION OF INFRARED UP-CONVERSION MATERIAL CaS: Eu, Sm
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
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 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..
Journal of Infrared and Millimeter Waves
- Publication Date: Aug. 01, 2005
- Vol. 24, Issue 4, 301 (2005)
OPERATIONAL METHOD OF TOTAL PRECIPITABLE WATER RETRIEVED FROM SATELLITE MULTI-CHANNELS' INFRARED DATA
[in Chinese], and [in Chinese]
A physical retrieval method of total precipitable water (TPW) by GMS-5 satellite infrared-split window channels and MODTRAN radiative transfer model was developed. TPW retrieval tests by using data of summer in 1998 were performed and the verification of retrieved results by using radiosonde data was given, whose RMSE A physical retrieval method of total precipitable water (TPW) by GMS-5 satellite infrared-split window channels and MODTRAN radiative transfer model was developed. TPW retrieval tests by using data of summer in 1998 were performed and the verification of retrieved results by using radiosonde data was given, whose RMSE was about 3.30mm. To apply a physical retrieval method operationally, a scheme different from one method above was designed, which was performed through GMS-5 multi-infrared channels’ data and RTTOV7- a fast radiative trasfer model, and whose RMSE was about (4.09mm). The results show that computation cost of the method for RTTOV7 is reduced greatly, which is satisfied for operation purpose..
Journal of Infrared and Millimeter Waves
- Publication Date: Aug. 01, 2005
- Vol. 24, Issue 4, 304 (2005)
STUDY OF GROUND-BASED LW INFRARED RADIATION MEASUREMENT
[in Chinese], and [in Chinese]
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 miThe 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..
Journal of Infrared and Millimeter Waves
- Publication Date: Aug. 01, 2005
- Vol. 24, Issue 4, 309 (2005)
IMAGE TRANSITION REGION EXTRACTION AND SEGMENTATION BASED ON LOCAL COMPLEXITY
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]
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 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).
Journal of Infrared and Millimeter Waves
- Publication Date: Aug. 01, 2005
- Vol. 24, Issue 4, 312 (2005)
SELF-CONSISTENT NONLINEAR COMPUTATION OF A 28GHZ GYROTRON AT THE SECOND HARMONIC
[in Chinese], and [in Chinese]
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 outputGyrotron 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..
Journal of Infrared and Millimeter Waves
- Publication Date: Aug. 01, 2005
- Vol. 24, Issue 4, 317 (2005)
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