Imaging Characteristics And Application Of Square-aperture Planar Microlens Array

The square-aperture planar microlens array is fabricated by ion exchange on a special glass substrate.The microlens is buried under the surface of the glass substrate,which not only avoids the interference of the environment temperature and humidity,but also performs very well in optical performance.Compared with the traditional microlens array,the gap between the lens elements is reduced,and the filling ratio is greatly improved,so that the optical information transmission is fully utilized.It has been widely used in optical communication,optical convergence,shaping,imaging and so on.The square-aperture planar microlens array and micro-pattern array overlap will produce Moiré fringes.The study on the formation mechanism of the square-aperture planar microlens array can improve the application range of the square-aperture planar microlens array and provide the theoretical basis for the further study of the square-aperture planar microlens array.The Fourier principles of Moiré fringe produced by the square-aperture planar microlens array and micro-graphics array are discussed in this paper.The square-aperture planar microlens array is regarded as 2-D grid lines,and the analytical formula of Fourier transform for 2-D Moiré fringes of the square aperture planar microlens array is derived by using the principle of Fourier transform of 1-D Moiré fringe.Moreover,the low frequency(1,-1)Moiré fringe is analyzed in detail.Particularly,the period,amplification and synchronization of Moiré fringe with different angles are studied,and the experimental is carried out by using the different 2-D grid template and different the micro-graphics array.Research results show that the experimental values agree well with the theoretical values and it will provide theoretical basis for the application and research of the square-aperture planar microlens array.In the study of the imaging characteristics of the planar aperture microlens array,When the monochromatic parallel light is incident perpendicularly to the microlens array,the same image as the lens array is observed at a specific distance along the optical axis,without lens imaging the object can the phenomenon called the Talbot effect.Based on the Talbot effect of 1-D grating and 2-D periodic objects,the distribution of the light field of the square aperture microlens array in the Fresnel diffraction region is analyzed.The imaging conditions are discussed by using the transfer function method.1,-1,± j of the three special imaging situation to study.This will expand the practical application of square-aperture microlens arrays.In application,the influence of square-aperture microlens array on the external quantum efficiency of OLED is studied.The internal quantum efficiency of OLED has been close to 100% with the new phosphorescent light emitting material,only 20% of the emitted light from the organic layers can obtain in OLED.According to the difference of the refractive index difference between the OLED substrate,the anode layer,the organic light-emitting layer and the air,the reasons for the low light efficiency of OLED and the solutions are introduced,Combined with the characteristics of microlens array,the influence of different sizes and different arrangements on the OLED luminous efficiency is discussed,and Numerical simulation is carried out to obtain the optimal lens array parameters.