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In order to achieve a real-time and visual observation of multi-plane images,a method using light-emitting materials is proposed.A 3D object can be divided into a series of 2D slices along the optical axis.With an efficient and fast 3D Gerchberg-Saxton algorithm,a computer-generated phase hologram is obtained and a numerical reconstruction is carried out on the computer.The process of 3D Gerchberg-Saxton algorithm is expounded,and the experiment for reconstruction and visualization of multi-plane images based on LC-SLM is conducted.With the grey level-phase curve of the LC-SLM,the computer-generated phase hologram is converted to gray-scale hologram,which is loaded to the LC-SLM to reconstruct the 3D light fields.The fluorescence characteristic of quantum dot materials is used to achieve the visualization of the light fields.Experimental results show that the optical reconstruction is in good agreement with numerical simulation.This technique is applicable in medicine,military,3D display,micromachining and micro-technology.

Digital Micromirror Device (DMD) is employed as spatial light modulator to construct a digital maskless lithography system,which can be used to fabricate micro-nano photonic device conveniently.The imaging process of the periodic structure in the coherence light is analyzed.According to the numerical simulation and experimental result,the imaging process should be explained by the principle of Abbe′s imaging.With this system,2D periodic structure with the period of 900 nm is fabricated but defect is introduced.So DMD is a practical tool to fabricate submicron-sized pattern.

In this paper, using the self-made Ge20Sb15Se65 chalcogenide glass as matrix material, we design an infrared octagon dispersion flattened photonic crystal fiber, and the mid-IR dispersion and transmission characteristics are numerically studied using the multipole method. Results show that when we control the duty ratio (d/Λ) in 0.323–0.367, the dispersion and transmission properties in the 3–5 μm range are adjustable. When we set the hole spacing Λ=3.4 μm, hole diameter d=1.1 μm, in the 4.1–4.9 μm band, the fiber dispersion fluctuates between-0.8 ps·nm-1·km-1 and 0.8 ps·nm-1·km-1, and shows single-mode transmission, low loss (LossAeff2) characteristics, thus it is suitable for nonlinear applications in mid-IR band.

Large mode area photonic crystal fibers (PCFs) have attracted much attention, owing to their applications in such as high power delivery, high power fibre amplifiers and fiber lasers. As an ideal candidate for fabricating mid-infrared fibers, chalcogenide glass possesses some unique advantages, such as high refractive indices (2.0-3.5), low photon energies (lower than 350 cm-1), tailorable compositions, and large infrared transmission window(from 1.0 to 20 μm). In this paper, we present a novel type of effectively single-mode chalcogenide glass Ge20Sb15Se65PCF with utra-large mode area as well as small confinement loss (lower than 0.1 dB/m for the fundamental mode, high confinement loss exceeding 2 dB/m for the higher-order mode at 10.6 μm).