Design of a freeform lens array based on an adjustable Cartesian candela distribution

This is the authors' abstract. We don't add key points for this paper.

Light-emitting diode (LED) modules can be flexibly disassembled and assembled and have inherent advantages in large-area lighting applications. In this paper, an efficient method is proposed to design an LED freeform lens array for direct lighting based on an adjustable Cartesian candela distribution. The Cartesian gradient candela distribution (CGCD) is adjusted and determined through the initialized design of a single freeform lens and a diffuser plate. The layout of the LED lens array can then be optimized by controlling the semi-angle of the light intensity distribution (SALI). A design example shows that the uniformity of the lens array increases by 11.63% through only a two-round iterative optimization. Both the simulation and experimental results are discussed to verify the proposed design. The freeform lens array is expected to expand the applications of mini- or micro-LED devices.