共查询到20条相似文献,搜索用时 0 毫秒
1.
《中国光学快报(英文版)》2017,(10)
A signal processing method of realizing a large-range displacement measurement in a sinusoidal phasemodulating laser diode interferometer is proposed. The method of obtaining the dynamic value of the effective sinusoidal phase-modulating depth is detailed, and the residual amplitude modulation is also taken into account.Numerical simulations and experiments are carried out to compare this method with the traditional one.We prove that, with this method, the sinusoidal phase-modulating laser diode interferometer can realize a centimeter-level displacement measurement range with high precision, which is much better than the traditional method. 相似文献
2.
As there exist some problems with the previous laser diode (LD) real-time microvibration measurement interferometers, such as low accuracy, correction before every use, etc., in this paper, we propose a new technique to realize the real-time microvibration measurement by using the LD sinusoidal phase-modulating interferometer, analyze the measurement theory and error, and simulate the measurement accuracy. This interferometer utilizes a circuit to process the interference signal in order to obtain the vibration frequency and amplitude of the detective signal, and a computer is not necessary in it. The influence of the varying light intensity and light path difference on the measurement result can be eliminated. This technique is real-time, convenient, fast, and can enhance the measurement accuracy too. Experiments show that the repeatable measurement accuracy is less than 3.37 nm, and this interferometer can be applied to real-time microvibration measurement of the MEMS. 相似文献
3.
We proposed a high accuracy image sensor technique for sinusoidal phase-modulating interferometer in the field of the surface profile measurements. It solved the problem of the CCD's pixel offset of the same column under two adjacent rows, eliminated the spectral leakage, and reduced the influence of external interference to the measurement accuracy. We measured the surface profile of a glass plate, and its repeatability precision was less than 8 nm and its relative error was 1.15%. The results show that it can be used to measure surface profile with high accuracy and strong anti-interference ability. 相似文献
4.
A sinusoidal phase-modulating (SPM) laser diode (LD) interferometer for real-time surface profile measurement is proposed and its principle is analyzed. The phase signal of the surface profile is detected from the sinusoidal phase-modulating interference signal using a real-time phase detection circuit. For 60 × 60 measurement points of the surface profile, the measuring time is 10 ms. A root mean square (RMS) measurement repeatability of 3.93 nm is realized, and the measurement resolution reaches 0.19 nm. 相似文献
5.
Photothermal modulation of laser diode wavelength: application to sinusoidal phase-modulating interferometer for displacement measurements 总被引:5,自引:0,他引:5
Xuefeng Wang Xiangzhao Wang Feng Qian Gang Chen Gaoting Chen Zujie Fang 《Optics & Laser Technology》1999,31(8):559-564
In this paper, a novel laser-diode (LD) sinusoidal phase-modulating (SPM) interferometer, which utilizes a photothermal technique for LD wavelength modulation, is proposed to measure displacements with a nanometer accuracy. In conventional LD–SPM interferometers, the LD intensity modulation is concurrent with the wavelength modulation, which increases measurement errors. Using the photothermal technique, the LD wavelength modulation can be accomplished with negligible concomitant intensity modulation, and the measurement errors are thus eliminated. The computer simulations and experiment results verify the usefulness of this novel interferometer. 相似文献
6.
A sinusoidal phase-modulating fiber-optic interferometer insensitive to the intensity change of the light source 总被引:1,自引:0,他引:1
Xuefeng Wang Xiangzhao Wang Yingming Liu Caini Zhang Danyang Yu 《Optics & Laser Technology》2003,35(3):219-222
In a conventional laser-diode sinusoidal phase-modulating (LD-SPM) interferometer, the wavelength of the LD is modulated by varying its injection current. The intensity modulation concurrent with the wavelength modulation leads to measurement errors. A photothermal-modulation method has been proposed to decrease the intensity change of the LD; however, this method cannot be used to measure vibration with a high frequency, and the beam diameter is too large to be used to measure minute objects. In this paper, we propose LD-SPM fiber-optic interferometer, in which the effect of the intensity change of the light source on measurement is eliminated. The diameter of the light beam is less than 0.5 mm. Using this interferometer, we measured displacements of a mirror driven by a piezoelectric transducer. The measurement repeatability is less than 1 nm. 相似文献
7.
To resolve the conflict of large measurement range and high accuracy in the existing real-time displacement measurement laser diode (LD) interferometers, a novel real-time displacement measurement LD interferometry is proposed and its measurement principle is analyzed. By use of a new phase demodulation algorithm and a new phase compensation lgorithm of real-time phase unwrapping, the measurement accuracy is improved, and the measurement range is enlarged to a few wavelengths. In experiments, the peak-to-peak amplitude of the speaker vibration was 2361.7 nm, and the repeatability was 2.56 nm. The measurement time was less than 26μs. 相似文献
8.
Movements of a surface profile are measured with a two-grating interferometer using sinusoidal phase-modulation. Since sinusoidal phase-modulating (SPM) interferometry can record a phase change due to the movement of an object in the interference signal, the SPM interferometer is suitable for measuring the movement of the object. Some experiments show that the two-grating interferometer can measure a sinusoidal vibration with amplitude of several tens of microns and a step movement with a magnitude of several microns. 相似文献
9.
10.
In sinusoidal phase modulating laser diode (LD) interferometer, the injection current of the LD is sinusoidally modulated to realize the modulation of the wavelength. However, the light intensity of LD is also modulated, which affects the measurement accuracy. An all-fiber sinusoidal phase modulating LD interferometer for real-time displacement measurement is proposed where the influence of the intensity modulation is eliminated with a new algorithm. It is made clear that an optimal depth of the sinusoidal phase modulation (SPM) exists in the algorithm. Moreover, the SPM depth is locked at the optimal value by controlling the injection current with a feedback control system. The feasibility of the proposed interferometer for displacement measurement is verified by experiments. 相似文献
11.
Laser diode interferometer used for measuring displacements in large range with a nanometer accuracy
In this paper, the displacement of an object is measured with a photothermal phase-modulating laser diode interferometer. A feedback control system is designed to reduce the measurement errors caused by the fluctuations in the optical wavelength of the laser diode and the vibrations of the optical components in the interferometer. A new method is proposed to enlarge the measuring range of displacement. Using this method, the measuring range is enlarged from half wavelength to nearly 125 μm and the measurement accuracy is about 1 nm. The simulation and experimental results have shown the usefulness of the method and the feedback control system. 相似文献
12.
Newly found reflection properties of the Fizeau wedge interferometer are shown to be of particular advantage in obtaining
efficient multi-wavelength operation of dye lasers. Use is made of the fact that the reflecting Fizeau wedge can ensure at
once a selective feedback for a given wavelength and quasi-total reflection in an other direction for all other wavelengths.
Fully independent tuning of two 0.02 nm lines is obtained with short pulse (2 ns) N2-laser pumping using a single Fizeau wedge. 相似文献
13.
14.
15.
《中国光学快报(英文版)》2015,(9)
To determine the amplitude of weak sinusoidal water surface acoustic wave(WSAW), a method based on the spectrum analysis of the phase-modulated interference signal is developed. Calculated from the amplitude spectrum of the detection signal, a characteristic ratio indicates that the phase-modulation depth of a WSAW is suggested by determining the amplitude of a WSAW according to their functional relationship. Experimental investigations for a 4 k Hz WSAW evaluate the measurement's precision with an amplitude measurement standard deviation of 0.12 nm. The measurement accuracy also is demonstrated by the experimental investigations.The theory of this method is briefly described, and the experimental setup is presented. 相似文献
16.
In this paper, we propose a sinusoidal phase modulating (SPM) interferometer that is insensitive to external disturbances, and its measuring principle is analyzed theoretically. In the SPM interferometer, the interference signal is detected by a high-speed image sensor based on a low-speed CCD and a signal processing circuit is used to obtain the phase of each point on the surface. Therefore, the surface profile can be measured real-time. The experiments measuring the surface profile of a wedge-shaped optical flat show that the measurement time of the SPM interferometer is less than 10 ms, the repetitive measurement accuracy is 4.2 nm. The results show that the impacts of nonlinear distortion of the piezoelectric transducer (PZT) and part external disturbance are removed. 相似文献
17.
针孔直径的大小是影响自参考干涉波前传感器测量精度的重要因素,在实际应用中应根据测量精度要求以及强度通过率来选择.首先基于傅里叶光学理论分析了针孔直径对参考波前质量以及强度通过率的影响,然后通过数值仿真和实验对其进行证实.研究结果表明,当针孔直径等于艾里斑直径的一半时可以产生高质量的参考波前,对于峰谷值不小于一个波长的畸变波前,其参考波前的均方根值低于λ/100.这些理论分析和实验结果可为自参考干涉波前传感器的设计和精度分析提供有价值的参考和指导.
关键词:
自适应光学
自参考干涉波前传感器
针孔直径
强度通过率 相似文献
18.
19.
In a conventional sinusoidal phase-modulating laser-diode (SPM-LD) interferometer, the wavelength of the LD is sinusoidally modulated by varying its injection current. However, the intensity modulation is associated with the wavelength modulation, which affects the measurement accuracy. We propose an SPM-LD interferometer insensitive to the intensity modulation of the light source, in which the influence of the intensity modulation is eliminated by choosing the appropriate sinusoidal phase modulation depth. Computer simulations and experiments are performed for real-time displacement measurement with the proposed SPM-LD interferometer. The measurement accuracy has been improved and the measurement repeatability is less than 1 nm. No additional components are required in our proposed method that leads to a simple system compared with the other previously proposed methods. 相似文献
20.
Song Zhang Yidong Tan Zhou Ren Yongqin Zhang Shulian Zhang 《Applied physics. B, Lasers and optics》2014,116(3):609-616
We introduce a new signal processing method based on phase meter into heterodyne microchip Nd:YAG laser feedback interferometer. The nanometer resolution and a higher measurement speed are realized. The factors determining the accuracy are analyzed. The displacements of the Physik Instrumente nanopositioning system and two piezoelectric transducers were measured. Experimental results indicate laser feedback interferometer’s ability of measuring nanoscale displacement and present promising application prospects in noncooperative targets measurement. 相似文献