光场显微镜实现裸眼三维实时显示

提出了一种将光场显微镜与裸眼三维显示技术相结合的方法,实现了利用光场显微镜对微观样品进行三维裸眼实时观察的技术。该技术将光场显微镜得到的子图像阵列直接投影在微透镜阵列的焦平面上,在空间一定区域内双眼可分别观看到两幅不同视角图像,使观察者产生立体视觉。该系统具有结构简单,无需相干光源,无需佩戴特殊眼镜,可多人同时观看等优点,应用前景广泛。     

瑞奇-康芒两角度检测法的一种波像差解读方法

瑞奇-康芒法是大口径平面元件面形检测的有效方法.通过分析检测光瞳到被检平面的位置转换关系以及波像差到面形误差的幅值转换关系,分别对检测得到的波像差以及干涉仪离焦产生的Power进行转换处理,利用最小二乘法计算出瑞奇-康芒两角度检测时的干涉仪离焦量,从而获得被检平面的面形误差分布.实验部分给出了第4项到第37项泽尼克多项...     

浅谈如何合理性选配和组建物理实验仪器系统

介绍了浙江大学物理实验中心合理性选配和组建物理实验仪器系统的方法和经验,并以光学实验室为例展开探讨.     

Time‐resolved coherent anti‐Stokes Raman spectroscopy impulsively excited by supercontinuum

Time‐resolved coherent anti‐Stokes Raman scattering (CARS) impulsively excited by a supercontinuum (SC) is investigated. We show that it is critical to optimize the temporal overlapping of the constituent solitons of a SC in order to impulsively excite vibrational modes over a broad frequency range. The cross‐correlation frequency‐resolved optical gating technique is utilized to retrieve the optical response function of molecules under SC impulsive excitation, and background‐free CARS with spectral resolution significantly better than the bandwidth of the probe pulses is achieved. Copyright © 2011 John Wiley & Sons, Ltd.     

Femtosecond stimulated Raman spectroscopy

Advances in the field of Femtosecond Stimulated Raman Spectroscopy (FSRS), a new time‐resolved structural technique that provides complete vibrational spectra on the ultrafast timescale, are reviewed. When coupled with a femtosecond optical trigger, the time evolution of a reacting species can be monitored with unprecedented <25 femtosecond temporal and 5 cm^‐1 spectral resolution. New technological and theoretical advances including the development of tunable FSRS and a background‐free FSRS format are discussed. The most recent experimental studies focus on ultrafast reaction dynamics in electronically excited states: isomerization in cyanobacterial phytochrome, ultrafast spin flipping in a solar cell sensitizer, and excited state proton transfer in green fluorescent protein. The use of FSRS to directly map multidimensional reactive potential energy surfaces and to probe the mechanism of reactive internal conversion is prospectively discussed.     

辐照电子在光纤芯处能量沉积的计算

为了用尽可能低的辐照电子能量在光纤芯处形成大的性质改变,模拟了0.1～1 MeV能量的电子辐照二氧化硅.发现每一特定能量的电子辐照二氧化硅时,在其中有个能量沉积最快的位置.计算得到0.447 4 MeV能量的电子在单模光纤中心能量沉积最快,分析发现对于这个能量的电子多数可以穿透到光纤芯处,电子能量在光纤芯处的沉积主要是由于电子能量的减小造成的.这些结果可为用电子辐照光纤制作光器件时的初始电子能量选择提供参考.     

GPON体系结构研究

千兆比特无源光网络(GPON)是一种面向下一代网络(NGN)的接入技术,它具有速率高、传输距离长、效率高和可伸缩性强等关键优势.同时,GPON支持引入更高带宽的以太网新业务,并能低成本提供传统的语音服务.介绍了GPON的标准化进展,分析了GPON的系统结构和协议参考模型,并给出了传输汇聚层的分层结构.     

用Bragg光纤测量气体浓度

基于气体的光谱吸收特性,本文提出了一种采用Bragg空芯光纤作为吸收池的新型光纤气体传感器.运用解析法和微扰分析法求解了Bragg空芯光纤中的相对灵敏系数.由于场分布主要集中在芯区,对气体损耗较为敏感,因此,这种光纤气体传感器具有灵敏度高、快速响应、结构简单的特点.耦合多个波长可实现对多种气体同时测量.     

Influence of Er-doped superfluorescent fiber source's spectrum-stability on the SNR of fiber optic gyroscopes

The output spectrum-stability of Er-doped superfluorescent fiber source (SFS) was measured by changing the temperature around the excited Er-doped fiber (EDF). With the experiment results, the influences of the SFS's spectrum-stability on the signal-to-noise ratio (SNR) of fiber optic gyroscope (FOG) were simulated. The simulated results demonstrate that the SNR of FOG will change no matter the power, mean wavelength or the spectral bandwidth of the light output from the Er-doped SFS is changing. The results show that the changing of SNR caused by the output power's variation is three orders of magnitude larger than that caused by the variation of mean wavelength or bandwidth. And the main factor influencing the stability of FOG's SNR is the temperature-stability of the output power of Er-doped SFS.     

Line width analysis of a tunable optical filter based on free-space optics

The line width of a tunable optical filter based on free-space optics was analyzed. The relationship between the line width and the Gaussian beam waist was theoretically derived and experimentally verified. The experimental results meet the theoretical analysis well, which is beneficial for the design of a tunable optical filter based on free-space optics.