近日，刊登在美国《国家科学院院刊》上的一项研究宣称，科研人员复制了萤火虫发光器官的结构，设计出新型的被称为发光二极管（LED）的小型高效灯具，从而增加了其光传播能力。
昆虫表皮的纳米材料能帮助它们有效地控制光偏振、构造色彩以及光学指数，并且这些材料主要用于管理射入光。此外，诸如萤火虫“灯笼”之类的生物性发光器官，在同异性交流时，会发出强光信号。
韩国科学技术院生物与脑工程学部的Jae-Jun Kim及其同事注意到有效的光传播在萤火虫的性交流过程中发挥关键作用。他们用电子显微镜研究了萤火虫发光器官的结构，发现萤火虫的发光器官由一个反射层、一个发光层和一个透明外层组成。而且重要的是，与腹部的其他部分不同，发光器的外层结构成行、有序排列，就像农田中的农作物那样。
Kim研究小组从萤火虫身上获得了灵感，设计并制造出了一系列新型LED，它们由反射杯、发光的LED芯片和外层有微小的、高度有序结构花纹的透明镜头组成。
测试表明，与平滑的镜头不同，这种有花纹的透镜在全范围可见光波长上能更好地对光进行传导——甚至可以与昂贵的抗反射镀层相媲美。同时，能够最有效地穿过这种经过改造的透镜的光波长符合萤火虫生物冷光的中心波长。
作者提出，这些研究结果能够帮助促进电视、照相手机、汽车以及医学和家庭照明用高功率LED的低成本透镜的开发。(生物谷Bioon.com)
DOI:10.1073/pnas.1213331109
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Biologically inspired LED lens from cuticular nanostructures of firefly lantern
Jae-Jun Kima, Youngseop Leea, Ha Gon Kimb, Ki-Ju Choic, Hee-Seok Kweonc, Seongchong Parkd, and Ki-Hun Jeonga,1
Cuticular nanostructures found in insects effectively manage light for light polarization, structural color, or optical index matching within an ultrathin natural scale. These nanostructures are mainly dedicated to manage incoming light and recently inspired many imaging and display applications. A bioluminescent organ, such as a firefly lantern, helps to out-couple light from the body in a highly efficient fashion for delivering strong optical signals in sexual communication. However, the cuticular nanostructures, except the light-producing reactions, have not been well investigated for physical principles and engineering biomimetics. Here we report a unique observation of high-transmission nanostructures on a firefly lantern and its biological inspiration for highly efficient LED illumination. Both numerical and experimental results clearly reveal high transmission through the nanostructures inspired from the lantern cuticle. The nanostructures on an LED lens surface were fabricated by using a large-area nanotemplating and reconfigurable nanomolding with heat-induced shear thinning. The biologically inspired LED lens, distinct from a smooth surface lens, substantially increases light transmission over visible ranges, comparable to conventional antireflection coating. This biological inspiration can offer new opportunities for increasing the light extraction efficiency of high-power LED packages.
