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Liu F.,Beijing Institute of Technology | Yu Z.,Beijing Institute of Technology | Yang W.,North Night Vision Science and Technology Group Co. | Zheng H.,Chongqing Jialing Huaguang Optical Electronic Science and Technology Co. | Zhang S.,Beijing Institute of Technology
Guangxue Jishu/Optical Technique | Year: 2014

IGZO film, as the active layer of thin film transistor, is prepared by different sputter power. The film morphology and the electrical characteristics of IGZO film are measured by scanning electron microscopy and Hall effect measurement system. The instability of IGZO TFT prepared by different sputter power under gate bias stress is studied. The result shows that, in a certain range, the film prepared by lower sputter power has rough surface, more defect density and lower carrier concentration. Positive gate bias induces IGZO-TFT positive voltage threshold shift, but negative gate bias stress do not produce voltage threshold shift.


Lin Q.,Beijing Institute of Technology | Jin W.,Beijing Institute of Technology | Guo H.,Beijing Institute of Technology | Zhang Y.,North Night Vision Science and Technology Group Corporation | Li M.,North Night Vision Science and Technology Group Corporation
Guangxue Xuebao/Acta Optica Sinica | Year: 2012

Dual-band and multi-band imaging techniques get more and more attention of the national military. As a key part, dual-band optical systems, especially visible light/long-wave infrared (VIS/LWIR) wide-band imaging systems, become the focus of research. The dual-band imaging systems for several major structural forms, including reflective, catadioptric and refraction forms are analysed, and the composition and characteristics of the refraction form are introduced. For the shortcomings of the dual-band system, a VIS/LWIR common-window objective lens in the refraction form used in handheld field is designed. The system's main technical indicators are: 0.6-0.8 μm (VIS), 8-12 μm (LWIR), f́ VIS=47 mm, f́ IR=58 mm, 2ω=9.8°, F VIS=2, F IR=1.3. Design results meet all the indicators, and the image quality meets the requirements in both bands. The size of the entire optical system is about 51 mm×93 mm×136 mm, which is compact and practical.


Li X.,The Key Laboratory on Night Vision Technology | Li X.,North Night Vision Science and Technology Group Co. | Lu Q.,North Night Vision Science and Technology Group Co. | Zhang Y.,North Night Vision Science and Technology Group Co.
Zhenkong Kexue yu Jishu Xuebao/Journal of Vacuum Science and Technology | Year: 2012

We addressed the characteristics of the Na2KSb(Cs) multi-alkali photocathode and its photoluminescence. Four different types of antimony-alkali compounds films, Na3Sb, K3Sb, Na>2K<1Sb, and Na2KSb, were deposited by alternative, thermal chemical vapor deposition (CVD) of Na, K and Sb, respectively, on glass substrates in the ambient environment. The impacts of the deposition conditions, including the deposition rate, layer thickness, substrate temperature, and stoichiometric ratio (Na, K, and Sb), on the photoluminescence and fluorescence were evaluated. The film growth was well controlled by on-line monitoring the photoelectron current and the leakage current. The fluorescence of the films was characterized at a laser wavelength of 785 nm. The results show that the stoichiometric ratio strongly affects the fluorescence intensity. For example, when it comes to fluorescence intensity, the Na2KSb films outperform the other 3 types of films. The highest intensity was observed with the Na2KSb grown at a ratio of 2:1:1; and as the ratio deviated from 2:1:1, its intensity decreased, accompanied with ablue-shift. We suggest that the stoichiometric ratio of the Na2KSb films be controlled by means of its fluorescence intensity.


Li J.,North Night Vision Science and Technology Group Co. | Fan H.-P.,North Night Vision Science and Technology Group Co. | Xie Z.-Y.,North Night Vision Science and Technology Group Co. | Zhou X.-H.,North Night Vision Science and Technology Group Co. | And 2 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2013

Through the classification of vehicular infrared night vision system and comparing the mainstream vehicle infrared night vision products, we summarized the functions of vehicular infrared night vision system which conclude night vision, defogging, strong-light resistance and biological recognition. At the same time, the vehicular infrared night vision system's markets of senior car and fire protection industry were analyzed. Finally, the conclusion was given that vehicle infrared night vision system would be used as a safety essential active safety equipment to promote the night vision photoelectric industry and automobile industry. © 2013 SPIE.


Li X.,North Night Vision Science and Technology Group Co. | Yu F.,Yunnan University | Song K.,North Night Vision Science and Technology Group Co. | Qian Y.,North Night Vision Science and Technology Group Co. | And 2 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2011

This paper describes the measuring method of fluorescence for membrane layer of Na2kSb antimony-alkali compound under glass window and quartz window excited by the laser of wavelengths of 514.5 nm and 785nm. Through comparing the fluorescence intensity of Na2KSb antimony-alkali compound under glass window and quartz window respectively when excited by laser of wavelength of 514.5 nm, it is found that the fluorescence intensity of Na2kSb layer excited with wavelength of 785nm is more suitable for the analysis of membrane layer of Na2ksb antimony-alkali compound under glass window and quartz window. By excitation with the laser in wavelengths of 514.5 nm and 785nm, peak wavelengths of fluorescence spectrum of membrane layer of Na2KSb antimony-alkali compound are measured as 898nm and 872nm and the corresponding transition energy levels are 1.42eV and 1.38eV respectively. Through the analysis of fluorescence spectrum of membrane layer of Na2KSb antimony-alkali compound, it is proved that photoluminescence is an effective tool for the research of membrane layer of Na2KSb antimony-alkali compound. Besides, further increasing the control precision of components of Na 2KSb, the synthesis process, and the material structure, will further increase the sensitivity of Na2KSb multi-alkali photocathode, and consequently further improve the performance of devices. © 2011 SPIE.


Miao Z.,Light Technology | Shi F.,North Night Vision Science and Technology Group Co | Cheng H.,North Night Vision Science and Technology Group Co | Wang S.,North Night Vision Science and Technology Group Co | And 3 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2015

In order to know the influence of activation processes on GaAs photocathodes, three GaAs samples were activated by a fixed current of cesium source and different currents of oxygen source. The current of caesium source is same during activation to ensure initial adsorption of caesium quantum is similar, which is the base to show the difference during alternation activation of caesium and oxygen. Analysed with the activation data, it is indicated that Cs-to-O current ratio of 1.07 is the optimum ratio to obtain higher sensitivity and better stability. According to double dipole model, stable and uniform double dipole layers of GaAs-O-Cs:Cs-O-Cs are formed and negative electron affinity is achieved on GaAs surface by activation with cesium and oxygen. The analytical result is just coincident with the model. Thus there is an efficient technological method to improve sensitivity and stability of GaAs photocathode. © SPIE. Downloading of the abstract is permitted for personal use only 2015.


Wang D.-H.,National University of Defense Technology | Niu Z.-D.,National University of Defense Technology | Zhang P.-Y.,North Night vision Science and Technology Group Co. | Chen Z.-P.,National University of Defense Technology
Guangdian Gongcheng/Opto-Electronic Engineering | Year: 2012

Sea-sky-line detection is an important component involved in infrared image Auto Target Recognition (ATR) techniques. Through analyzing the characteristics of infrared images under sea-sky background, a fuzzy recognition algorithm is proposed based on four feature score factors. Firstly, Radon transform is performed on gradient images in order to choose sea-sky-line candidates. Secondly, fuzzy synthetical judgment is made combining information of 4 specific features. Finally, sea-sky-line recognition result is given according to the judge values. The algorithm comparison and real data test results show that this method is widely applicable, powerful in resistance to interferences and noises and has a high recognition rate, which can be used to effectively extract sea-sky-lines under complex backgrounds, thus lay a good foundation for further application such as target recognition.


Yang W.,North Night Vision Science and Technology Group Co.
Guangxue Jishu/Optical Technique | Year: 2014

Two kinds of thin-film with full different physic performances are combined together on K9 glass substrate to form composite film layer, achieving anti-electromagnetic interference and high light-transmitting. Technical performance index: light-average transmissivity is not less than 90% in 400 nm-1100 nm. The resistance value on anti-electromagnetic interference shielding surface is 4±0.5Ω/□ to achieve a good anti-electromagnetic interference shielding. A complex film construction composed of electromagnetic interference resistance and reducing reflecting coating is designed to meet the technical performance requirements and coating experiment is carried out. The experiment result shows that microstructure of optical thin film can be improved by ion assisted deposition technology to increase optical performance, physical performance and durability of complex thin film.


Wang R.,Light Technology | Wang R.,North Night Vision Science and Technology Group Co. | Bai X.-F.,Light Technology | Bai X.-F.,North Night Vision Science and Technology Group Co.
2015 International Conference on Optoelectronics and Microelectronics, ICOM 2015 | Year: 2015

This paper analyzed the technical characteristics of GaAs photocathode electrode with high sensitivity. Through measuring the output current of micro channel plate, the relation between incident light intensity and output current is summarized. Besides, we proposed the light intensity measurement method for the third generation low light level (LLL) image intensifier. By comparing our method with the method of measuring the intensity of the photoelectric multiplier tube, our method has the advantages of high sensitivity, fast response, independent of temperature, and measurement simplicity. The results indicate implicit linearity between micro channel plate and intensity of light under 10-4∼10-1lx environment. It verifies the validness of our method. © 2015 IEEE.


Bai X.,Light Technology | Bai X.,North Night Vision Science and Technology Group Corporation | Yin L.,Light Technology | Yin L.,North Night Vision Science and Technology Group Corporation | And 6 more authors.
Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering | Year: 2013

Luminance gain, which was directly affect the image quality of night vision system in low light level condition, was an important technological index to evaluate the ability to amply image light intensity. In order to improve the repetitive characteristic of image intensifier's luminance gain, changing process of light source color temperature, light source output luminance and screen luminance had been studied respectively, theory of light source color temperature, light source output luminance and screen luminance impacting on luminance gain had been analyzed. The conclusion with warming-up of light source should not be less than 15 minutes and work time for image intensifier should not be less than 1 minute had been established. Test result showed that repetitive characteristic of image intensifier was better than 3% when light source had been warmed-up sufficiently and image intensifier's work time was controlled strictly.

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