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In real-time imaging applications, the auto-focus algorithm and hardware structure must be adapted to the limited resources for fast and accurate real-time auto-focusing. In this paper, to obtain more precision, a new clarity evaluation function base on image's edge energy is proposed. Then, we present the corresponding FPGA hardware implementation which has simple structure. Additionally, utilizing the prior knowledge during the climbing process, a new climbing algorithm for the auto-focus which has the random start point is proposed. The experiment results show the proposed auto-focus algorithm can reduce the steps during the climbing and accelerate the auto-focus speed simultaneously.

According to special application, surveillance camera working in the ultra-low temperature and high pressure vessel is designed. By request of optics and electronics system on temperature, research focus on the design from selection of the structure material, thermal insulation, the adaptability of optical system in the ultra-low temperature and high pressure environment. Finally, It is confirmed that opto-Mechanical structure with double layers thermal insulation of PIPA and ITO optical window have benefit on thermal insulation for the camera working in this ultra-low temperature(−196°C) and high pressure(0.5MPa) environment. All the opto-Mechanical material which may be contact with ultra-low high pressure liquid can also be consistent with liquid.

Rang-Instaneous-Doppler (RID) processing is widely used in ISAR imaging of maneuvering target and acceptable image can be achieved when the amplitude modulation effect of scatterers echoes can be neglected during intergation time, whereas, the RID method based on the assumption above does not work properly when the variant amplitude modulation of scatterers' echoes involved, such as ship target. In this paper, a multicomponent amplitude modulation and linear frequency modulation(AM-LFM) signal model developed and a fast parameter estimation technique-DechirpClean method proposed. To achieve the best quality in DechirpClean ISAR image, a new effective optimum imaging interval selection scheme addressed. The performance of proposed method is verified by comparing the result with the image produced by conventional RID method from the real data processing.

The existing fabric defection method mainly depend on the brightness of visual light or gray intensity of image, therefore, the effect of classification and identifition is deteriorated when the high quality fabric image unable to obtained. Aim at solving difficulties or fatal disadvantage in existing fabric defects detection system, a novel system of fabric defects detection system by using the synthetic Aperture radar (SAR) is presented. Different from the mechanism used in imaging approach, some vital disadvantage can be avoided in SAR fabric defect detection system. Theory of SAR method is introduced, key problem in SAR technique is brought forward and solved, the numerical example study and analysis and the result of real data processing verified the effectiveness of proposed method.

To obtain high resolution ISAR image of ship target in motion with narrow-bandwidth T/R devices and a low-speed A/D sampler, an effective imaging method based on Linearly Modulated Stepped Frequency (LMSF) is proposed in this paper. Firstly, the signal model is developed and analyzed. Secondly, a band coherent processing method is proposed to eliminated the error induced by the translational motion and the high range profile is obtained. Finally, the high resolution of cross range is achieved by using the Dechirp Clean techinque. The theory analysis and the resutl of real data processing demonstrate the performance of the proposed method.

The silane-modified, acid-treated carbon nanotubes (silane-modified HCNTs) were prepared using acid-treated carbon nanotubes (HCNTs) and octyltriethoxysilane (OTES) via the sol–gel process. The silane-modified HCNTs and the HCNTs were characterized by Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, and transmission electron microscopy (TEM). The Raman spectra showed that there were larger reactive sites on nanotubes treated in the H2SO4/HNO3 mixture acid for 2 h. The chemical structural effects on the morphology, dispersion, and thermal and emission properties of the carbon nanotube emitter paste were investigated by scanning electron microscopy (SEM), SEM mapping, ultraviolet–visible (UV–vis) spectrophotometry, differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), emission pattern, and current–voltage curve measurements. The UV–vis spectrophotometry indicated that the silane-modified HCNTs could be stably dispersed in toluene over 96 h. It was found that the compatibility between silane-modified HCNTs and the matrix material was mainly due to the interpenetrating polymer network structure between them. The thermal stability of the silane-modified HCNT emitter paste was improved by increasing the content of silane-modified HCNTs. A homogeneous emission was observed when using the silane-modified HCNT emitter paste. The current density extracted from the sample with the silane-modified HCNT emitter paste was higher than that with the HCNT emitter paste at a constant voltage. The turn-on fields of 3 wt % silane-modified HCNT emitter paste and HCNT emitter paste were 1.9 and 5.6 V/µm, respectively.