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Xu R.,Beijing Institute of Technology | Xu R.,Beijing Key Laboratory for Precision Optoelectronic Measurement Instrument and Technology | Wang X.,Beijing Institute of Technology | Wang X.,Beijing Key Laboratory for Precision Optoelectronic Measurement Instrument and Technology | And 5 more authors.
Applied Optics | Year: 2016

In order to test a direct-detection ladar in a hardware-in-the-loop simulation system, a ladar scene projector is proposed. A model based on the ladar range equation is developed to calculate the profile of the ladar return signal. The influences of both the atmosphere and the target's surface properties are considered. The insertion delays of different channels of the ladar scene projector are investigated and compensated for. A target range image with 108 pixels is generated. The simulation range is from 0 to 15 km, the range resolution is 1.04 m, the range error is 1.28 cm, and the peak-valley error for different channels is 15 cm. © 2016 Optical Society of America.


Xiao H.,Harbin Institute of Technology | Zuo B.,Harbin Institute of Technology | Tian Y.,Beijing Institute of Technology | Tian Y.,Shanghai Institute of Electro Mechanical Engineering | And 7 more authors.
Applied Optics | Year: 2012

We investigated the joint influences exerted by the nonuniform aerodynamic flow field surrounding the optical dome and the aerodynamic heating of the dome on imaging quality degradation of an airborne optical system. The Spalart-Allmaras model provided by FLUENT was used for flow computations. The fourth-order Runge-Kutta algorithm based ray tracing program was used to simulate optical transmission through the aerodynamic flow field and the dome. Four kinds of imaging quality evaluation parameters were presented: wave aberration of the exit pupil, point spread function, encircled energy, and modulation transfer function. The results show that the aero-optical disturbance of the aerodynamic flow field and the aerodynamic heating of the dome significantly affect the imaging quality of an airborne optical system. © 2012 Optical Society of America.


Tian Y.,Beijing Institute of Technology | Tian Y.,Shanghai Institute of Electro Mechanical Engineering | Tian Y.,Beijing Key Laboratory for Precision Optoelectronic Measurement Instrument and Technology | Xu R.,Beijing Institute of Technology | And 10 more authors.
IEEE Transactions on Antennas and Propagation | Year: 2016

Edge diffraction of a beam combiner will adversely affect the field uniformity in the observation plane. In order to suppress the edge diffraction, the serrated edge design method is proposed. According to the equivalence principle, a field uniformity analysis method was proposed to compute the spatial field distribution radiated from the aperture of a beam combiner. In order to separate the direct wave from diffracted wave, the spatial field is transformed into the time- and angular-domain spectrum by inverse Fourier transform. First, the height of serrations is designed by analog of the equivalent trapezoidal amplitude taper. Then, the number of serrations was designed by the assumption of isosceles and right triangles. Finally, the shape of serrations was designed by changing the interior angle of serrations. A serrated edge design example is also proposed and analyzed. By comparing the field uniformity in spatial, time, and angular domains before and after serrating the edges, the amplitude and phase ripples decrease from 1.85 dB and 12.16° to 0.53 dB and 3.98°, respectively. The results show that the field uniformity is significantly improved. © 2016 IEEE.


Tian Y.,Beijing Institute of Technology | Tian Y.,Shanghai Institute of Electro Mechanical Engineering | Li Q.,Shanghai Institute of Electro Mechanical Engineering | Zhang L.,Shanghai Institute of Electro Mechanical Engineering | Li Z.,Beijing Institute of Technology
Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering | Year: 2012

In order to meet high temperature, high dynamic range, high resolution requirements of infrared imaging guidance seeker to target simulator in the hardware-in-the-loop, a new infrared space light modulator was proposed, based on the narrow band, high extinction ratio, and high dynamic range characteristics of one-dimensional photonic crystal. The optics transfer characteristics of one-dimensional photonic crystal was analyzed and simulated. The relation between transmittance and normalized frequency and the effect of changing layer number, periodical optical path and optical index on the band gap were analyzed in detail. The optics transfer characteristics of one-dimensional photonic crystal with center defect was aslo analyzed and simulated. The results of calculation provide theoretical support for the new technology.


Zhang L.,Shanghai Institute of Electro Mechanical Engineering | Tian Y.,Shanghai Institute of Electro Mechanical Engineering | Li Q.,Shanghai Institute of Electro Mechanical Engineering
Hongwai yu Jiguang Gongcheng/Infrared and Laser Engineering | Year: 2012

In recent years, considerable progress has been made in the dynamic infrared scene projector at home and abroad. As a core part of hardware-in-the-loop system, the technical performance of dynamic infrared scene projector limits the performance of the whole simulation platform. The research status of dynamic infrared scene projector at home and abroad was summarized in this paper. The technical requirement of new type of dynamic infrared scene projector matching the infrared imaging precision-guided technology was prospected. In view of the development level of dynamic infrared scene projector, it's needed to explore hybrid infrared projection technology and intensify the research of new projector to solve the limitation on current projector.

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