本文根据部分相干光成像的理论,分析了光源的空间相干性及时间相干性对相衬显微镜成像质量的影响,并对相衬环同光源的形状及大小的匹配问题进行了讨论.结果表明,部分相干光照明将引起位相物体像的对比度下降.由于相衬环在一定程度上改变了非零频谱的特性,因此像面上的光强分布亦有所改变.如果对照明条件及滤波方式进行一些改进,相衬显微镜的成像质量将会得到改善.
本文报道了使用光栅压缩器对后向受激布里渊散射(SBS)脉冲的时间压缩。实验结果表明后向SBS是以线性扫频为主要成份.获得了脉宽为40ps的1.06μm压缩脉冲,压缩比为20倍.
Direct numerical simulation of intense laser–solid interactions is still of great challenges, because of the many coupled atomic and plasma processes, such as ionization dynamics, collision among charged particles and collective electromagnetic fields, to
We examined a 1514 nm eye-safe passively Q-switched self-optical parametric oscillator. The nonlinear crystal is an a-cut Nd:MgO:PPLN crystal, and the size of the crystal was 6 mm × 2 mm × 30 mm with 0.4 at.% Nd3 doped and a grat
报道了有关足球烯分子甲苯溶液中简并四波混频实验.测量出足球烯C70分子和C60分子的三阶超极化率张量y1111分量分别为1.2×10-30 esu和4.0×10-31 esu.对应于固体样品的三阶非线性光学系数X1111分量分别是2.5×10-8 esu和8.5×10-9 esu.此结果表明了足球烯分子是现有的非线性光学材料中具有较大三阶非共振电子极化率材料之一.文中还利用自由电子模型解释了非线性光学极化率的起源.
Eight-port optical routers are widely used in cluster-mesh photonic networks-on-chip (NoC). By using 24 groups of cross-coupling two-ring resonators, a 1-stage 8-port polymer optical router is proposed, which can optically route 7 channel wavelength data