Research On Error Compensation Of Single-frequency Laser Measuring System Based On LabVIEW

Laser interferometry technology has been developed very maturely at present. It’s very difficult to improve the resolution and precision of interferometer optically in displacement measurement. With the continuous development of hardware technology and software technology, that makes high-resolution, high-precision laser interferometer to develop. Specifically, the method on hardware circuit or software is used to filter the distortion and deformation of signals caused by various error sources.Error sources of Single-frequency laser interferometer is mainly composed of three parts. The first part is inherent error of the single-frequency laser measurement system. including quantization error,non-orthogonal error and non-linearity error and so on.the second part of the error is caused by the environment,including refractive error,optical thermal drift; the third part is the system installation error, including Abbe error, cosine errors. In all these sources, there are three types of errors h ave been research hotspot.It include wavelength error caused by the change of the change of air refraction index that is due to changes of environment,the nonlinear error of the single-frequency laser interferometer caused by parameter error and position error of the optoelectronic components and environmental factors,and Abbe error of measurement.In order to improve the measurement accuracy of laser interferometer measurement system, we must compensate or eliminate the three parts of error.To compensate Abbe error, while measuring the length of the guide,the pitch angle and yaw angle were measured.We have been established compensation models according to the characteristics of the two parts of the error. According to the mathematical model, measuring length and angle program have been written in the LabVIEW environment, and using LabVIEW software to complete real-time compensation for displacement measurement. Length and angle can be measured simultaneously by software,Finally, in the laboratory, I have been verify the measurement software of length by one-dimensional rail and single-frequency laser interferometer system.