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Virtual binocular stereoscopic camera models that can be used in generation of stereoscopic images or videos of virtual 3D scenes by use of computer graphics techniques are presented and analyzed in detail. It is found that the paralleloptical-axis model is most appropriate for synthesizing stereoscopic images or videos of virtual 3D scenes. Mathematical formulae for calculating the camera position and ‘lookat’ position of both the left and right virtual cameras therein are developed. Light-source visibility filtering with a depth variation constraint is proposed to speed up the ray-tracing-based soft shadow rendering of virtual 3D scenes and meanwhile to eliminate the drawback of generating fake shadows associated with the original light-source visibility filtering method; dual light-source visibility filtering scheme is suggested to make shadows reflected in a mirror surface correctly feature penumbra. The stereoscopic video experimentally generated by use of our method shows pleasing visual realism and impressive stereoscopic effects.

Based on partially coherent polarized light transmission characteristics of the atmosphere, an intensity expression of completely coherent flashing light is derived from Andrews scale modulation method. According to the generalized Huygens-Fresnel principle and Rytov theory, the phase fluctuation structure function is obtained on condition that the refractive index profile in the atmosphere meet Von Karman spectrum, then get the arrival Angle fluctuation variance. Through the RMS beam width of gaussian beams in turbulent atmosphere, deviation angle formula of fully coherent gaussian beams in turbulence atmosphere is attained, then get the RMS beam width of partially coherent and derivation angle expression of GSM beam in turbulent atmosphere. Combined with transmission properties of radial polarized laser beam, cross spectral density matrix of partially coherent radially polarized light can be gained by using generalized huygens-fresnel principle. And light intensity and polarization after transmission can be known according to the unity of coherence and polarization theory. On the basis of the analysis model and numerical simulation, the simulation results show that: the light spot caused by atmospheric turbulence of partially coherent polarization will be superior to completely polarized light.Taking advantage of this feature, designed a new wireless suppression technology of atmospheric turbulence, that is the optimization criterion of initial degree of coherent light beam. The optimal initial degree of coherent light beam will change along with the change of atmospheric turbulence conditions,make control the beam’s initial degree of coherence to realize the initial degree of coherence of light beam in real time and dynamic control. A spatial phase screen before emission aperture of fully coherent light is to generate the partially coherent light, liquid crystal spatial light modulator is is a preferable way to realize the dynamic random phase. Finally look future of the application research of partially coherent light.

With the fast growing and popularization of smart computing devices, there is a rise in demand for accurate and reliable indoor positioning. Recently, systems using visible light communications (VLC) technology have been considered as candidates for indoor positioning applications. A number of researchers have reported that VLC-based positioning systems could achieve position estimation accuracy in the order of centimeter. This paper proposes an Indoors navigation environment, based on visible light communications (VLC) technology. Light-emitting-diodes (LEDs), which are essentially semiconductor devices, can be easily modulated and used as transmitters within the proposed system. Positioning is realized by collecting received-signal-strength (RSS) information on the receiver side, following which least square estimation is performed to obtain the receiver position. To enable tracking of user’s trajectory and reduce the effect of wild values in raw measurements, different filters are employed. In this paper, by computer simulations we have shown that Gaussian mixture Sigma-point particle filter (GM-SPPF) outperforms other filters such as basic Kalman filter and sequential importance-resampling particle filter (SIR-PF), at a reasonable computational cost.

Build theory model of intensity scintilla characteristics of laser atmospheric transmission. Under the analysis of the model, focus on theory model simulation of effect model simulation of laser transmission characteristics. And simulation results show that: the laser scintilla caused by atmospheric turbulence increased with the transmission distance and turbulence intensity increased; The longer wavelengths of light intensity, the smaller intensity scintilla; The plane waves of laser scintilla is smaller than spherical wave and so on. Finally research of the laser transmission characteristics in the atmosphere is prospected.