用于大范围高精度实时位移测量的半导体激光干涉仪

现有的半导体激光干涉仪存在测量精度与测量范围的矛盾。本文提出一种新的实时位移测量半导体激光干涉仪，并分析了干涉仪的测量原理。首先提出一种新的解相算法，它通过两路实时相位探测电路从干涉信号中得到待测量相位，消除了光强波动、初始光程差、电路放大倍数、调制深度、Bessel函数等参数对测量精度的影响，提高了测量精度。其次，提出一种扩大测量范围的技术，并用解包裹电路得到真实相位和待测量的位移, 将测量范围从半个波长提高到几个波长。在实验中，测得喇叭的峰峰值为2361.7nm，重复测量精度为2.56nm，测量时间为

基于低速面阵CCD的正弦相位调制干涉测量

正弦相位调制(SPM)干涉测量技术用于表面形貌测量时, 需要帧速高于300 frame/s的图像传感器, 同时要求调制信号频率与图像传感器帧速成确定的整数倍关系。提出一种基于低速CCD(30 frame/s)的帧速可调的高速图像传感技术, 通过控制每帧像素总数提高CCD帧速, 研制出一种高帧速图像传感器, 帧速可达300～1600 frame/s, 且每帧大小连续可调。将该CCD传感器用于正弦相位调制干涉泰曼-格林干涉仪, 测量镀膜玻璃板表面形貌, 当CCD图像传感器的帧速与调制信号频率呈16, 8, 4

实时测量表面形貌的正弦相位调制半导体干涉仪

提出一种实时测量表面形貌的正弦相位调制半导体激光干涉仪。利用实时相位检测电路，从正弦相位调制干涉信号中解出被测量物体表面形貌的相位。在实验中，测量了楔形光学平板的表面形貌，对表面形貌上的60

Optimized sinusoidal phase mask to extend the depth of field of an incoherent imaging system

Wavefront coding is a powerful technique that can be used to extend the depth of field of an incoherent imaging system. By adding a suitable phase mask to the aperture plane, the optical transfer function of a conventional imaging system can be made defocus invariant. Since 1995, when a cubic phase mask was first suggested, many kinds of phase masks have been proposed to achieve the goal of depth extension. In this Letter, a phase mask based on sinusoidal function is designed to enrich the family of phase masks. Numerical evaluation demonstrates that the proposed mask is not only less sensitive to focus errors than cubic, exponential, and modified logarithmic masks are, but it also has a smaller point-spread-function shifting effect. (C) 2010 Optical Society of America

Cubic sinusoidal phase mask: Another choice to extend the depth of field of incoherent imaging system

Wave-front coding is a well known technique used to extend the depth of field of incoherent imaging system. The core of this technique lies in the design of suitable phase masks, among which the most important one is the cubic phase mask suggested by Dowski and Cathey (1995) [1]. In this paper, we propose a new type called cubic sinusoidal phase mask which is generated by combing the cubic one and another component having the sinusoidal form. Numerical evaluations and real experimental results demonstrate that the composite phase mask is superior to the original cubic phase mask with parameters optimized and provides another choice to achieve the goal of depth extension. (C) 2009 Elsevier Ltd. All rights reserved.

正弦相位调制位移干涉测量技术中调制频率的优化选择

针对正弦相位调制（SPM）干涉测量技术用于位移测量时，调制频率对干涉信号相位解调的影响，提出一种调制频率的优化选择依据。通过对干涉信号的频谱进行分析，发现当被测位移幅度较小时，较小的调制频率即可满足相位解调的要求；而当被测位移较大时，必须相应地增大调制频率，才能获得比较准确的测量结果。模拟计算以及实验结果表明，被测位移信号的幅度每增大四分之一测量光源波长，调制频率需要相应增大4倍于被测信号频率的大小，才能满足正弦相位调制位移干涉测量技术信号处理的需要。

一种基于PSD器件的改进型角度测量方法

提出一种基于平行平板干涉仪的改进型角度测量方法。为了实现较大的偏转角度测量，该平行平板干涉仪引入了一位置探测系统。平面反射镜的引入提高了角度测量的分辨率。实验验证了可在近3度的范围内实现被测偏转角度的高精度测量。并且作为一位相调制型干涉仪，其小角位移测量实验的重复精度可达5.5×10^(-8)rad。

正弦相位调制的频域光学相干层析成像

提出一种基于正弦相位调制的频域光学相干层析成像,利用正弦相位调制干涉术探测复频域干涉条纹的实部和虚部,重建复频域干涉条纹。对该复频域干涉条纹作逆傅里叶变换后,消除了频域光学相干层析成像中存在的复共轭镜像以及直流背景和自相干噪声。对玻璃片样品进行了层析成像实验。实验结果表明,采用正弦相位调制的频域光学相干层析成像,将可利用的成像深度范围扩大到原来的2倍,实现了全深度探测的频域光学相干层析成像。

Application of bacteriorhodopsin film for polarization phase-shifting interferometry

Photoinduced anisotropy in bacteriorhodopsin (BR) film is based on photoanisotropic selective bleaching of BR molecules under linearly polarized excitation light. It is modulated by the polarization orientation of the linearly polarized light. The anisotropic information recorded in the BR film is read by a circularly polarized light, which is in turn converted into an elliptical polarized light by the BR film. The rotation angle and the ellipticity of the elliptical polarized light are dependent on the polarization orientation of the linearly polarized excitation light. A phase-shifting interferometer based on the photoinduced anisotropy of BR film is presented theoretically and experimentally. Phase shift is controlled by the polarization orientation of the external excitation light, thus, the phase shift can be controlled without moving parts inside the interferometer, which contributes to the mechanical stability of the system.

室温下稳定的多波长掺铒光纤激光器的研究

通过在线形谐振腔中引入一段缠绕在压电陶瓷上的单模光纤作为正弦相位调制器，使得激射波长的损耗不固定，抑制由于掺铒光纤的均匀展宽效应引起的模式竞争，从而避免了在室温下不稳定的单波长激射，实现了多波长掺铒光纤激光器的稳定输出。为了获得平坦的多波长输出，在谐振腔里使用了一个损耗峰位于1530nm处的长周期光纤光栅，以获得较为平坦的增益谱。通过两个3dB耦合器制成的反射型梳状滤波器的滤波作用，实验中观察到稳定的多波长激射，相邻波长间隔约为0．45nm。中心9个波长的输出功率平坦度为10dB，边模抑制比大于25dB。

Measurement of small vibration amplitudes of a rough surface by an interferometer with a self-pumped phase-conjugate mirror

The application of a Michelson interferometer with a self-pumped phase-conjugate mirror to measure small vibration amplitudes of a rough surface is described. The distorted wave front of the light that is diffusely reflected from the rough surface is restored by phase conjugation to provide an interference signal with a high signal-to-noise ratio. The vibration amplitudes of a stainless-steel sample are measured with a precision of similar to 5 nm. (C) 2000 Optical Society of America OCIS codes: 120.3180, 190.5040, 120.7280.

A phase-shifting vectorial-shearing interferometer with wedge plate phase-shifter

We present a novel phase-shifting vectorial-shearing interferometer with a wedge plate phase-shifter. The interferometer is based on a modified Mach-Zehnder configuration; the common-path nature makes it capable of testing the wavefront of a short coherence-length light source, such as a laser diode. Vectorial shear (shearing in the x and y directions simultaneously) in an arbitrary direction is introduced by inserting two wedge plates orthogonally in two arms, respectively. One of the wedge plates is split into two parts (parallel part and wedge part); phase shift is produced by moving the wedge part in contact along the parallel part. The moving distance for a 2 pi phase shift is a few millimetres in specific conditions. The wedge plate phase-shifter increases the moving distance for phase shift and makes the control of phase shift relatively easy. We also discuss the lateral shear error and phase shift errors induced by wedge plates. The lateral shear error is small enough to be ignored; the phase shift error is determined mainly by the wedge angle error. Lastly, we give the experimental results of phase-shifting interference fringes in vectorial shear mode.