Improved two-dimensional orthogonal cylindrical lens arrays optical system with controllable focus profile for uniform irradiation

Abstract

A novel orthogonal cylindrical lens arrays (OCLA) system has been proposed to obtain two-dimensional (2D) uniform irradiation with controllable focus width and transformation of beam-shape at the same time. The system is composed of two pairs of mutual OCLA and aspheric lens. Based on adaxial matrix optics and scalar quantity diffraction integral theory, the principle of this system with controllable focus profile is analyzed and optimum design of system parameter are presented in detail respectively. The simulated results show that by a suitable choice of system parameters two-dimensional uniform focusing of laser beams with controllable focus width from several hundred microns to several millimeters can be achieved. And the system converts a circular laser beam into a flat-top square focal spot of steeper edges without side lobes. In order to confirm our theoretical considerations, with Zemax optical design software, confirm regular focus width with the variation of the distance between two groups of mutual OCLA, the shape and intensity distribution of focal spot is confirmed in agreement quite well with theory.

Spherical aberration of planar square aperture microlens array

“…According to the design of lens arrays optical system with controllable focus width [20] , PMLA system with continuously adjustable focal length was proposed, which was made up of two pieces of square aperture PMLA and an aspherical lens. The structure schematic diagram of system with continuously adjustable focal is shown in Fig.…”