Theory And Experiment Of Micro-Angle Measurement Based On Two-dimensional Moire Fringes Generated By Square Aperture Microlens Array

With the rapid development of science and technology,the fabrication of planar microlens array is becoming more mature with the technique of lithographic ion-exchange.The microlens is buried under the surface of glass substrate,which not only avoids the interference of environment temperature and humidity,but also performs very well in optical performance fields as small diameters,large numerical aperture,and high imaging resolution,and good focusing,collimating,transformation,multiple imaging and comprehensive imaging ability.Compared with the traditional microlens array,the gap between the microlens elements is reduced,which avoid some light information leakage and the filling ratio is greatly improved.Therefore the optical information transmission is fully utilized.This planar microlens array realizes a broad application in improving the sensitivity,other microoptical imaging systems and optical processors,diffraction imaging characteristics,etc.A high-precision optical method is proposed to measure the small angle with 2D Moiréfringe generated by square aperture microlens array in this dissertation.The comprehensive development of Moiréfringe and small angle measurement technology plays an important role in many fields in metrology science.Moiréfringe is very sensitive to the small rotation,slight twisting,micro-deformation,and also has some characteristics such as good accuracy,high sensitivity and non-contact.So that small angle is increasingly applied to the Moiréfringes with much attention.When the??????????Abstract Moiréfringe is applied to small angle measurement,the measurement of small angle is based on the difference of width of the moiréfringe in different angle.In this paper,we need to simply the square-aperture microlens array,and are performed in fourier analysis and geometric analysis.The principles of Moirépitch variation are analysed under the different dimensions of a<b,a=b,and a>b.The result of comparing the two is same,but the principle of them is different.By analysing the expression of the pitch of the two-dimensional Moiréfringe and fourier optical theory,the principles of Moirépitch variation are analysed.Simulation analysis of the small angle expressions at different initial angles shows that the included angle?<3°is suitable for small measurements.The principles of Moirépitch variation are analysed under the different dimensions of a<b,a=b,and a>b,and select appropriate experimental sample.Then,the Moiréfringe pitch of square-aperture microlens array is analyzed theoretically and experimentally.Based on this,the experimental samples with a=0.3,b=0.4 were experimentally studied.The results showed that the theoretical analysis and the experimental information were generally consistent and met the experimental expectations.The Moiréfringe generated by the square-aperture microlens array provides theoretical and technical support for small angle measurement.It will broaden of the square aperture microlens array,and promoting the development of a combination of microlens and Moirés display technology.In summary,the research enriches the dynamic Moiré display of square-aperture microlens arrays.It provides a theoretical basis for the measurement of small angle between square-aperture microlens array and micrographics array with 2D Moiré in the fields of precision measurement,navigation and spaceflight,and promoting the development of a combination of microlens and Moirés display technology.