Research On Rock Deformation Measurement Device Based On Digital Holography

Digital holography combines optical holography,computer processing technology and digital optoelectronic technology,which is an important research hotspot for optical holography at worldwide.In order to achieve the measured holographic processing and reproduction,digital holography uses CCD instead of the traditional dry plate to achieve hologram recording in the computer simulation of optical diffraction process.In recent years,the study of rock deformation with the development of various disciplines has gradually emerged two different development trends: one is the mathematical mechanics analysis;the other is the experimental measurement.At present,the low cost,high precision,high sensitivity and non-contact measurement in the experimental measurement are the main research directions of the current scientific research workers.Interference measurement technology in digital holography can meet the above requirements,not only the low cost,and the measured object without contact,and the accuracy can reach the wavelength level.In this paper,digital interferometry is used to build a measuring device to measure rock deformation.I design device of optical path,build the test platform,adjust the optical path,selection of shale samples.Firstly,the hologram of the rock without external force is recorded,and the frequency of 100 g pressure is increased 8 times each time,and the hologram is recorded every time.After the deformation hologram is superimposed and reconstructed,the interference fringe of the object light wave is obtained.This streak reflects the deformation information of the rock.The shape of the rock and its deformation at the pressure of 100 g,200g and 800 g are obtained by analyzing the fringes.By importing the data into the MATLAB software,the shape variables and deformation positions of the rock under any pressure within 800 g can be obtained.At the end of this article,a summary and prospect of the results are presented.