光谱色散平滑的实验研究

为提高国内惯性约束聚变（ICF）装置的焦斑平滑能力，在对光谱色散平滑（SSD）技术理论分析的基础上，开展相关实验并研究其平滑机制。实验结合另一种焦斑平滑技术——分布式相位板（DPP）比较分析光谱色散平滑技术应用下的焦斑均匀性的变化。实验表明，利用光谱色散平滑技术中的正弦相位调制对光谱展宽并色散后，在色散方向上的焦斑均匀性有明显改善，120μm内的光强调制被平滑，其平滑能力依赖于光谱色散平滑技术参量的选择；焦斑的低频光谱强度变化很小，但中高频光谱强度下降，焦斑质量有良好的改善，焦斑的不均匀性从40％降低到1

Encoded cell grating array in anti-counterfeit technology

The dot matrix hologram (DMH) has been widely used in anti-counterfeiting label. With the same technology and cell array configuration, we can encode to the incidence beam. These codes can be some image matrix grating with different grating gap and different grating orientation. When the multi-level phase diffractive grating is etched, the incidence beam on the cell appears as an encoding image. When the encoded grating and DMH are used in the same label synchronously, the technology of multi-encoded grating array enhances the anti-counterfeit ability.

Precise determination of anomalous scattering factors of Ge by using X-ray resonant scattering

Variations of peak position of the rocking curve in the Bragg case are measured from a Ge thin crystal near the K-absorption edge. The variations are caused by a phase change of the real part of the atomic scattering factor. Based on the measurement, the values of the real part are determined with an accuracy of better than 1%. The values are the most reliable ones among those reported values so far as they are directly determined from the normal atomic scattering factors.

激光预处理对增透膜阈值的影响

激光预处理是提高光学薄膜激光损伤阈值的有效方法之一。本文就激光预处理前后增透膜损伤阈值的变化、破斑深度的变化、膜层中电场分布情况，分析了激光预处理对阈值的影响及原因。

沉积温度对LaF3薄膜性能的影响

abstract {LaF₃ single-layer coatings were prepared by thermal boat evaporation at the deposition temperatures of 189, 255, 277 and 321°C respectively. The crystal structures of the coatings were characterized by X-ray diffraction (XRD). A spectrophotometer was employed to measure its transmittance. Moreover, refractive index, extinction coefficient and cut-off wavelength were obtained from the measured transmittance spectral curve. The residual stress was evaluated by the Stoney's equation and optical interferometer. Laser induce damage threshold (LIDT) was performed by a tripled Nd:YAG laser system. The results show that the crystallization status becomes better with the deposition temperature increasing. Correspondingly, the grain size also gets larger. Meanwhile, the coatings become more compact and the refractive index increases. However, the absorption of coatings seriously rises and the cut-off wavelength drifts to the long wave. In addition, the residual stress also increases and the intrinsic stress plays a determinant role in the coating. The LIDT of the coating also enhances at high temperature.}