实现给定能量比离散光斑阵列的自由曲面分束器

Freeform lenses are used as freeform surface beam splitters to generate discrete spot arrays with arbitrary energy proportions. According to the law of conservation of energy, the incident beam is divided into a series of subregions corresponding to the spot array. For each subarea, variable separation is used to acquire the ray map between the input beam within the subarea and the corresponding spot. Further, a least squares method is used to construct the freeform surface following the ray map. Two design examples are provided to demonstrate the capabilities of freeform beam splitters: one could generate a Gaussian spot array with an equal energy proportion and the other could generate a square top-hat spot array with a predefined non-uniform energy proportion. Both freeform beam splitters exhibit light output ratios of over 89% considering Fresnel losses.