North Night Vision Science and Technology Group Co.

Kunming, China

North Night Vision Science and Technology Group Co.

Kunming, China
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Shi H.,Light Technology | Shi H.,North Night Vision Science and Technology Group Co. | Bin R.,Light Technology | Bin R.,North Night Vision Science and Technology Group Co. | And 4 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2017

The electronic structure and optical properties of pure and P-doped cubic-blende gallium arsenide (GaAs) for different P constants (x=0, 0.125, 0.25, 0.375) have been studied by the first-principles projected augmented plane potential approach based on the density functional theory and the generalized gradient approximation method. It shows that the P-doped material has a smaller lattice constant, which resulted in a local lattice distortion. The minimum of the conduction band moves to high energy level and the band gaps gradually become wide with gradual increase concentration of P impurity. The dielectric function are calculated based on Kramers-Kroning relations. The optical property studied from the calculated absorption coefficients shows that the adsorption peaks change obviously in the visible light wavelength area for the P-doped GaAs system. © 2017 SPIE.


Wang G.,Nanjing University of Science and Technology | Chang B.,Nanjing University of Science and Technology | Li X.,North Night Vision Science and Technology Group Co. | Fu R.,Nanjing University of Science and Technology | And 2 more authors.
Solar Energy Materials and Solar Cells | Year: 2017

The combination of thermionic and photoelectric emission for solar energy conversion has been studied for years. There are two concepts for this synergistic process: hot electron conversion (HEC), which supposes that the excited carriers equilibrate among themselves, and photon-enhanced thermionic emission (PETE), which is based on the excited electrons' complete thermalization with the material. Here we present a new concept, thermally enhanced external photoelectric emission (TEPE), which describes the synergistic process under the photoelectric emission model. An experimental setup was applied and a photodiode with a bialkali cathode was tested. A conversion efficiency of 1.97×10−2% under 400 nm illumination at 20 °C was achieved, and a double enhancement of the efficiency was observed with the temperature rising to 70 °C. Although the conversion efficiencies were small, the experiment demonstrates the energy conversion based on external photoelectric emission and the enhancement effect of heat. © 2016 Elsevier B.V.


Xu K.,Xian Institute of Applied Optics | Xu K.,North Night Vision Science and Technology Group Co. | Han K.,Xian Institute of Applied Optics | Han K.,North Night Vision Science and Technology Group Co. | And 2 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2017

To strive for the goal of further improving the overall performance of low-light-level Gen.III image intensifier tube, modifications and innovations in the making of GaAs photocathode are already underway revolving around the basis of existing research, through which the sensitivity of GaAs photocathode is considerably improved from 1200μA/lm to above 1800μA/lm, 2000μA/lm (typical value), and it won't drop within the 1000hrs' storage inside the station according to the experiment on the photoemission stability of high-sensitivity GaAs photocathode. In short, highly distinguished characteristics of high sensitivity GaAs photocathode like wide response range, superior quantum efficiency and 1.06μm infrared response wavelength, promise its remarkable significance in both the enhancement of the overall performance and the prolongation of the operational life-span of low-lightlevel Gen.III image intensifier tube. © 2017 SPIE.


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 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.


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.

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