The Reflecting Surface Of The Rotating Liquid

A large smooth area reflection surface formed by rotating liquid was studied by using optical interferometry technique and digital holography.This parabolic mirror was obtained by a mechanical rotating device.Using the Mach-Zehnder interferometer system study the surface of the rotating parabolic liquid.A spherical wave generated from the reflecting surface of the rotating liquid interfered with the plane wave and form an interference fringe.In order to achieve quick image acquisition,we use the digital image acquisition device CCD to capture the fringe image.We use the computer image processing program to analyse interferogram,and doing the calculation with the focus point of the spherical wave.Using the digital holographic technique we constructed the distribution of the wavefront.The spherical wave in recording plane was reproduced by digital holographic.If we acquire a series of interference fringe images continuously,it can obtain the changing of the rotating liquid paraboloid along with the time.The high precision of optical interference technology ensures the accuracy of measurement.The main contents of this paper are as follows:1.Build a rotating liquid turntable with the speed of 30 rad/min and 45 rad/min.Based on the uniform rotation system,and get a rotating liquid paraboloid mirror.2.Establish a Mach-Zehnder interferometer system to measure the reflected spherical wave of a rotating liquid surface.3.Using the fast and continuous acquisition function of the CCD to achieve the interference fringe pattern.4.Establish a relevant computer image processing system to analyze the interference fringe and holographic image.By the method of successive minus,searching the center of the concentric interference fringe and calculated the focal length of the liquid paraboloid.With the speed of 30 rad/min and 45 rad/min,the length between CCD and focal plane equals853 mm and 1020 mm.According to the position of the focus point,the distribution of the wavefront can be reconstructed in virtue of the digital holographic technique.In order to study the surface of a rotating liquid without any contact and interference by the digital interference technique and holographic imaging technology,we use a foundation for the application of the large area rotating liquid reflection mirror.