Research On Key Technology Of Multiplexed Measurement In Spatial Carrier Speckle Pattern Interferometry

Deformation and its first derivative are both key parameters in analyzing mechanical properties of materials.The simultaneous and accurate measurement of these two parameters is urgently required for practical applications in automotive and aerospace industries.Digital speckle pattern interferometry and digital shearography are widely used optical measurement methods due to their real-time,full-field,noncontact,and high-sensitivity advantages.The former is used to measure in-plane or out-of-plane deformation,while the latter is typically used to measure the first derivative of deformation.Spatial carrier speckle pattern interferometry multiplexed measurement methods are deeply studied in the paper to meet practical requirements of simultaneous measurement of deformation and its first derivative..The main research work and innovative achievements are as follows:1.A spatial carrier speckle pattern interferometry multiplexed measurement method based on Michelson interferometer is proposed to solve the problems of complex optical path structure and difficult spectrum separation in the existing multiplexed measurement methods.The proposed method realizes the simultaneous dynamic measurement of deformation and its first derivative.And the method can obtain simple spectrum distributions and ideal measurement results by changing the introduction position of reference beam to reduce beams in the optical path.2.A spatial carrier speckle pattern interferometry multiplexed measurement method based on the double imaging Mach-Zehnder is proposed to improve the convenience of shearing amount adjustment of the multiplexed measurement method based on Michelson interferometer.The proposed method realizes the simultaneous dynamic measurement of deformation and its first derivative.And the method can obtain measurement results with free shearing amount and shearing direction by adjusting carrier frequency and shearing amount using different components.3.A curved object speckle pattern interferometry measurement method based on the variable circle template matching is proposed to solve the phase error caused by surface curvature during the curved object speckle pattern interferometry measurement.The proposed method realizes the accurate measurement of deformation and its first derivative of curved objects.And the method can obtain accurate sub-pixel matching results by matching camera images with the variable circle template.Therefore,the effective curved shape information can be provided for the curved object speckle pattern interferometry measurement.4.A speckle pattern phase map filtering evaluation method based on smoothing spline is proposed to solve the problem that the speckle pattern phase map filtering condition cannot be judged during the continuous filtering process.The proposed method realizes the automation of the speckle pattern phase map filtering process.And the method can automatically judge the filtering condition of phase maps by calculating root-mean-square error of phase distribution smoothing spline fitting results.Therefore,the corresponding completed phase maps can be obtained.