激光直写技术作为一种新兴的低成本、高效、高精度的加工技术，可以适用于几乎任意自由度的二维或者三维微纳结构快速成型制备。这对光电子以及半导体微纳结构与器件的制备具有重大的意义。金属微纳结构在电子学和光子学中有着广泛的应用。本文综述了激光直写制备金属微纳结构相关研究进展。主要包括激光直写制备金、银、铜以及复合材料微纳结构与器件。随后重点综述了激光直写表面增强拉曼光谱微流道芯片相关的研究进展。随着环保要求的不断提高，功能性碳材料将会在更多领域得到广泛的应用。与传统的热碳化方法相比，激光直写工艺可以在材料的表面上实现精细的图案化微纳结构的制备。本文进一步综述了激光碳化直写碳功能材料相关研究进展。主要包括激光直写原位还原氧化石墨烯、激光碳化木材、叶子等木质材料。通过对本课题组的研究以及目前相关的研究成果进行综述，本文可为激光直写制备金属与碳材料微纳结构与器件研究及应用提供参考。

干涉高光谱图像是一类特殊的图像源, 其海量数据导致很难在有限带宽信道上传输。传统的方法是对数据进行压缩, 然后进行编码传输。但是压缩后的数据还是很大, 给数据的传输和存储带来很大困难, 而压缩感知技术可以很好地解决该类图像在传输时的问题。本文在压缩感知原有算法的基础上提出了更适用于干涉高光谱图像的基于自适应阈值的正交匹配追踪算法 (ATROMP), 该算法首先采用分块处理, 然后挑选出干涉条纹块。由于竖直干涉条纹具有较强的单方向特性, 水平全变分值较大。因此本文根据水平全变分值提取出图像中的干涉条纹, 进行自适应采样。然后采用一个自适应阈值来代替正则正交匹配追踪(ROMP)算法中的二次选取, 采用自适应阈值不仅可以保障每次选取的原子的相关性足够高, 而且每次可以适当地选取多个原子保证足够的循环次数, 避免了后续匹配度更高原子的遗漏。相比于传统 ROMP算法, 大量实验数据表明本文方法稀疏重建的精度可以得到明显的提高。

以LED为扩展光源, 提出一种基于照度分布分割与反馈的方法为LED设计非常紧凑的光学自由曲面透镜, 进而设计实现了大距高比(DHR)的直下式背光源。与子光学面联接构成光学面的过程相对应, 总照度分布被分割为子照度分布。通过修正子光学面来调整子照度分布, 使得总照度分布足够接近于目标照度分布, 所需光学面就被构建出来了。该设计过程不依赖于仿真, 简便易行, 适用广泛。作为实例, 一个非常紧凑(透镜的中心高度与LED尺寸相等)的自由曲面透镜被设计出来, 作为直下式背光源的配光透镜。仿真结果表明, 背光源照度分布的均匀度达到了0.91, 相对标准差(RSD)低至0.0202, 总的光能利用率达到了85.5%。

A simple model is presented to analyze the spectral shape and bandwidth dependence of the pulsecontrast and compressed pulse width in the chirped pulse amplification. The parameters of the 30 fslaser system are demonstrated as examples. Comparing with Top hat, Lorentzian, Sech2, Gaussian, 2ndSuper Gaussian and 10th Super Gaussian spectral pulse shape, the 2nd Super Gaussian spectral pulseshape can obtain better contrast in the case of less spectral bottom width. Those results are helpful tofind an optimized spectral shape in the chirped pulse amplification.

A two-dimension model is presented to analyze the spatial dependence of pulse contrast in the focal plane. The parameters of the SHENGUANG (SG) II laser system are demonstrated as examples. Comparing with the degradation in the beam centroid, the pulse contrast degrades more seriously in the transverse. This spatial degradation of pulse contrast can be improved, such as by controlling the spatial spectrum clipping.

We theoretically study the temporal contrast degradation by the spectral phase distortion in chirped pulse amplification (CPA) lasers. As an example, we analyze the impact of the surface qualities of the optical elements such as mirrors and grating in the stretcher and compressor on the temporal contrast. The temporal contrast declines fast in the case of a rapidly varying random surface error of the optical elements. When the values of PV, RMS and GRMS of the surface error curve are reduced, the temporal contrast is becoming better and better. And the temporal contrast can be improved after the surface error curve is to be spatial filtering. Those results are helpful for the choice of the surface parameters of the optical elements in the stretcher and compressor.

We theoretically study the temporal contrast degradation by the spectral phase distortion in chirped pulse amplification (CPA) lasers. As an example, we analyze the impact of the surface qualities of the optical elements such as mirrors and grating in the stretcher and compressor on the temporal contrast. The temporal contrast declines fast in the case of a rapidly varying random surface error of the optical elements. When the values of PV, RMS and GRMS of the surface error curve are reduced, the temporal contrast is becoming better and better. And the temporal contrast can be improved after the surface error curve is to be spatial filtering. Those results are helpful for the choice of the surface parameters of the optical elements in the stretcher and compressor.