流场光学诊断的光偏振相移数字剪切散斑干涉

本文提出了应用于流场光学诊断的使用光偏振相移的数字剪切散斑干涉技术，它具有如下两个显著的优点，首先，产生干涉效应的两相干光束均是物光束。它们通过几乎相同的光学元件与几何空间。这样可以降低测量过程中对环境的防震需求，便于工程中的实际应用。其二，采用光偏振相移方法来获取了干涉图上的位相信息，与通常使用的压电陶瓷相移方法相比，不需要复杂的标定，使用更为方便。     

Time Reversal for the Polarization State in Optical Systems

Abstract

The time-reversal operator for the polarization state can be successfully implemented in any optical system where a beam retraces its path. A Faraday rotator followed by a mirror realizes a device whose representative matrix is similar to the quantum mechanics time-reversal operator for the spin. Any effect of the medium birefringence is cancelled and, for linear polarization, the beam always returns opposite polarized with respect to the entrance state. Analogies with the operation of a phase-conjugation mirror are pointed out and suggested consequences of the novel optical configuration are given.     

高能激光光学系统偏振分析

本文详细地论述了反射式激光光学系统偏振态变化的起因。并得到几个重要结论。     

A Novel Technique for Spatial Phase-shifting Interferometry

Abstract

A novel technique for phase detection using three-step spatial phase-shifting interferometry is presented. The presented technique overcomes and studies the two main problems presented in the commonly used three-step phase-stepping technique. These problems deal with the leak of carrier frequency in the detected phase and the optimal carrier frequency to obtain the highest phase noise robustness.     

Polarization Effects in Heterodyne Interferometry

Abstract

A detailed analysis of the polarization effects which lead to nonlinearity in the non-ideal optical heterodyne interferometer is presented. Extensive use is made of the coherency matrix representation by setting up a ‘cross-coherency matrix’ representation. A generalized treatment of periodic phase errors (nonlinearity) is then presented. Individual contributions to the nonlinearity have been characterized as either ‘independent’ or ‘dependent’ phase errors. In the single-pass plane-mirror heterodyne system, to which the approach is applied, phase errors for rotational misalignment of the nominally orthogonal linearly polarized input states, beam splitter leakage, non-orthogonality, ellipticity and the effect of misaligned polarizer-mixer are explicitly considered. The latter effect is found to produce nonlinearity only when in combination with any one of the first three and is therefore a dependent phase error. The nonlinearity arising from ellipticity is identical with that from rotational misalignment except that it has an offset. Rotational misalignment and ellipticity produce nonlinearity at the second harmonic and are second order for practical set-ups. It is also found that combinations of positive (anticlockwise) and negative (clockwise) angular misalignments of the azimuth of the states, non-orthogonality and misorientations of the polarizer-mixer, all relative to the polarizing beam splitter axes, lead to different peak-to-peak nonlinearities in the given system.     

Optical Heterodyne Polarimeter for Studying Space-and Time-dependent State of Polarization of Light

Abstract

This paper describes an optical heterodyne polarimeter with a photodetector array by which the space- and time-dependent state of polarization (SOP) of light can be determined. Since no optical components for polarization control are used, the time response of the polarimeter is free from such components, but is basically limited to the frequency bandwidth of the photodetector array used. The signal and local oscillator beams are coherently photomixed to generate a beat photocurrent at every pixel of the photodetector array. The orthogonal linearly polarized two-frequency components of the local oscillator beam are superimposed with their respective counterpart orthogonally decomposed components of the elliptically polarized signal beam. The generated beat-photocurrent offers the significant physical parameters required for the determination of the space- and time-dependent SOP. The performance principle of the polarimeter is explained and confirmed experimentally.     

用于线宽测量的偏振干涉共焦显微测量方法

提出一种融合共焦显微技术和偏振干涉技术的偏振干涉共焦显微测量方法。利用共焦技术进行准确的焦点定位，以获得最佳的测量光斑；同时，利用照射到台阶边缘的不同偏振方向(平行和垂直于台阶边缘)的线偏振光反射后产生的相位变化不同这一特性，进行边缘定位。相位变化是利用外差干涉测相的方法得到的。这一系统完全符合共光路原则，有很强的抗干扰能力。利用该系统对标准线宽样板进行了测量，测量结果与中国计量科学研究院用原子力显微镜测量的结果，以及厂商提供的可溯源到美国NIST光学线宽标准的测量值都符合的很好；还对同一刻线进行了5次重复性测量，其极限偏差为20m。     

光谱域光纤白光干涉测量技术

光谱域光纤白光干涉测量技术(WLI)具有精度高、动态范围大、工程实用性强等优点,在光纤传感和精密测量领域有广泛的应用价值。本文回顾了光谱域光纤白光干涉测量技术的发展历程,重点介绍了本研究组在这一领域所开拓的基于相位测量技术的光谱域光纤WLI,包括傅里叶变换WLI及其相对测量术、波长扫描WLI、相移WLI、波数扫描WLI、互相关WLI、步进相移WLI,并展示了该技术在光纤温度、压力、应变等传感器中的应用。     

光纤外差干涉位移传感器

非接触式光纤外差干涉位移传感器是将半导体激光器线性调频技术和光纤传感技术相结合制成的1种新型外差干涉仪。它的位移测量范围可达26mm，分辨率为0．02μm；对不同材料、不同粗糙度的对象面，有着几乎相同的测量灵敏度和测量精度；探头和对象面无需严格垂直。     

光干涉法测量微机械零件变形的研究

介绍了用光干涉法测量微加速度计零件变形的研究。将准直单色光投射入由一玻璃片和被测件之间形成的空气楔中，被测件表面和玻璃片底面反射的光发生干涉，由面阵CCD接收。用快速傅立叶变换（FFT）图像处理方法得到被测微悬臂梁的三维形变图。该方法可对微小器件的微位移作分辨办为10nm的测量，并直观的显示测量结果。     

白光干涉法偏振耦合测试及数据采样分析

基于白光干涉原理,通过麦克尔逊干涉仪的光程补偿作用,检测保偏光纤空间分布寄生偏振耦 合强度和耦合点位置。经数据采样时域理论分析知:扫描步长增大时,耦合强度检测误差和耦合点位置判断误差呈线性增大。扫描步长小于500nm时,强度误差小于5%,位置误差在11mm之内。     

Polarization Component Phase Shifters in Phase Shifting Interferometry: Error Analysis

We have investigated the influence of the errors of the retardation and azimuth angle of the polarization components of a polarization phase shifter, on the phase measurement, in phase shifting interferometry.     

用于全景成像系统的一种新型光学非球面

介绍一种用于全景成像系统的单个复杂非球面前置元件,从几何光学的基本原理出发,给出了这种非球面的高斯分析和不同情况下的面形方程,利用正交拟合算法得到了便于实现光路计算的多项式表述,并成功地运用于光线追迹和像差计算。     

新型二阶非线性光学聚合物的研究

研究了互栓网络型聚合物的电晕极化及其二阶非线性光学性质，与其它类型极化聚合物进行的比较表明它是一种很有潜力的新型非线性光学材料。     

一种新型的微机械可变式光衰减器

介绍了一种新型的连续可变式微机械单模光衰减器的设计与制作。该光衰减器采用电磁型微驱动器驱动一个铁镍合金衰减片，使其插入两根准直的单模光纤的间隙中，依靠精密地调节衰减片切入光路中的位置而实现对传输光功率的连续衰减。采用硅微细加工技术成功地制作出了这种光衰减器，并对微驱动器的性能进行了理论分析。测试结果表明，当传输的光波长为1550nm时，该衰减器的平均插入损耗为2.5dB，衰减范围为2.5-45dB，回波损耗为40dB。     

A Parallel Fringe-scanning Algorithm for Phase-shifting Interferometry

Abstract

In connection with digital interferometry, the evaluation of phase-shifted interferograms can be speeded up by a digital image processor. A special parallel algorithm has been designed for scanning the saw-tooth shaped fringes. It is shown that the number of image passes (TC cycles) for a 2 ^j × 2 ^j pixel image is reduced to j instead of 2^j. Fringe scanning of a saw-tooth phase image and a pseudocoloured display of the continuous phase is obtained after 1·4s for 512 × 512 points.     

一种制备优质有机光学薄膜的新方法

提出了一种用真空蒸发和真空热压相结合的技术来制备优质有机光学薄膜的方法。用它制成的有机光学薄膜中没有任何残留有机溶剂,在放置过程中也不产生晶化,因而不会对光发生散射。在光通讯器件、有机发光、有机光存储器的制作等方面有广泛的应用前景。     

Polarization Aberration Effects Propagated in Optical Systems

Abstract

The propagation and imaging of polarized light through optical systems described by a polarization aberration expansion is treated by combining a scalar operator calculus with the Jones calculus. The martrix-operator framework provides a means for handling diffraction and propagation in optical systems containing polarization aberrations. An expansion for the polarization aberration function of an optical system, similar to the expansion of the wavefront aberration function into defocus, tilt, piston, and higher-order terms, is analysed. These polarization aberration terms introduce phase changes in the diffraction image proportional to the first and second derivatives of the non-polarization aberrated image structure.     

Novel Calibration System with Sparse Wires for CMB Polarization Receivers

A curl competent (also known as B-modes) in the cosmic microwave background (CMB) polarization is a smoking gun signature of the inflationary universe. To achieve better sensitivity to this faint signal, CMB polarization experiments aim to maximize the number of detector elements, resulting in a large focal plane receiver. Detector calibration of the polarization response becomes essential. It is extremely useful to be able to calibrate “simultaneously” all detectors on the large focal plane. We developed a novel calibration system that rotates a large “sparse” grid of metal wires, in front of and fully covering the field of view of the focal plane receiver. Polarized radiation is created via the reflection of ambient temperature photons from the wire surface. Since the detector has a finite beam size, the observed signal is convolved with the beam property. The intensity of the of the calibrator is reasonable (a few Kelvin or less) compared to sky temperature for typical observing conditions (～10?K). The system played a successful role for receiver calibration of QUIET, a CMB polarization experiment located in the Atacama desert in Chile. The successful performance revealed that this system is applicable to other experiments based on different technologies, e.g. TES bolometers.