Design of microlens arrays with aspheric surfaces for uniform illumination

The methods of wave optics and ray-field tracing are implemented for modeling microlens arrays (MLAs), taking into account the effects of coherence and polarization of the light source, randomization of the parameters of microlens arrays. The influence of the parameters of the radiation source (wavelength, curvature of the wavefront, beam radius, coherence radius, etc.) and the microlens array (periodic or random, aspect ratio, pitch size, refractive index, shape and profile of the array surface (convex, concave, aspheric), etc.) on the output parameters (intensity distribution, radiation pattern, optical efficiency) of the diffracted beam is studied. The numerical simulation of the intensity distribution and the spreading angle of diffracted beam is carried out. To calculate the optical efficiency of microlens arrays, a new approach to the ray field based on the coherent state representation has been developed. Such wave rays can simply be tracked along arbitrary curved surfaces. A user-friendly interface has been developed for entering the initial parameters of the light source and the MLA array, as well as for displaying graphical and informational modeling results. The measured intensity distributions of diffracted radiation by microlens array are compared with the simulation results for LD and LED sources.