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A new concept of photonic crystal fiber (PCF) with high nonlinearity and flattened dispersion was designed. The PCF structure is indeed a hexagon lattice. The bigger air holes in the outer rings are used to confine the light field into the core region for enhancing the nonlinearity. The flattened dispersion can be achieved by adjusting the diameters of six smaller air holes in the first ring, and six micro air holes are inserted between smaller air holes for higher nonlinearity and the better flattened dispersion. By optimizing the size of the smaller and micro holes, the PCF can reach to high nonlinearity of 23.3 W−1· km−1and the low dispersion of 51.32 ps/(nm·km) with the fluctuation range of 0.98 ps/(nm·km), which is within the wavelength range of 1 400 nm to 1 900 nm. The designed PCF can be used in important applications in realizing the Raman soliton self-frequency shift (RSSFS).

A novel method to automatically generate the depth map is presented, when the depth maps of reference images located before and after the target image in the same image sequence are given. A novel grid dividing method and a joint feature response model are proposed to adaptively select trace points, and an image deformation algorithm is given to track depth maps with the trace points. Experimental results show that the proposed method can generate depth maps effectively and accurately, which can meet the industrial needs in 2D-3D conversion.

An non-vertical stereoscopic 3-D display method by changing the parallax value of the parallax images is proposed. This method is capable of displaying virtual reality with high-immersion sense because the observing depth only depends on the parallax value. An experimental 3-D display system capable of producing high-immersion and virtual reality video images at 45 degree is developed. Furthermore, the effectiveness of the method is demonstrated by using this system.

In this paper the wavelength conversion in a 1cm long silicon-on-insulator (SOI) waveguide has been investigated numerically. The wavelength conversion efficiency is optimized by analyzing free carriers absorption (FCA) loss generated by two-photon-absorption (TPA). The free carriers life time is focused while other factors influencing noise figure are also considered.

With the different sizes of the structure parameters of the SOI(Silicon on Insulator) rib waveguide, the dispersion and the nonlinearity parameters are investiaged using the beam propagation method. It is found that for the same structure parameters, the dispersion and the nonlinearity parameter γ are different between the TE and TM modes. With the changing of the structure parameters the anomalous dispersion and the nonlinearity parameter γ can be up to 972 ps/km/nm and 1.065×106w-1.km-1 in the wavelength region near 1550nm.The high anomalous dispersion and the nonlinearity parameter γ means it’s a good candidate to realize parametric amplification and wavelength conversion.

The measuring mechanism of the self-aligned interferometer (SI) is analyzed in detail in the paper. The expression of nonlinear phase shift and its error expression are derived. The reasons of influencing on the measuring accuracy of the nonlinear phase shift are analyzed theoretically. The influences of the SI structure parameters on measuring the nonlinear phase shift are simulated and calculated. Properly selecting structure parameters in the SI, the optimal value and are obtained. A measuring system using the optimal structure parameters is set up. The measured nonlinear phase shift coincides with the theoretical value. When compared the measured with other testing values from reference [2], the deviation obtained in our experiment is smaller. The experimental results show that the measuring method with simulating and optimizing the structure parameters in the SI is effective and convenient. The measuring method improved will be applied widely in optical fiber communications and optical precise measurements.

We have analyzed the effects of various normally distributed nonuniformities of sampled fiber Bragg gratings on the reflective spectra and group time delay. Through numerical simulations we have drawn the following conclusions: (1) the magnitude of nonuniformity with normal distribution of the fiber’s average refractive-index modulation δ̅ n_eff greatly influences the characteristics of both reflective spectra and group time delay, whose suggested precision varies from 20% to 10%; (2) the nonuniformities of sampling periods P and sampling lengths L are important factors that influence the characteristics of the group time delay, and the accepted tolerance of dimensional precision of both P and L are ±4 μm; and (3) the tolerance of nonuniformity of the sampling period’s chirp coefficient is high, and its precision can be as great as 100% with few adverse effects.