Cho Hanlyun, Jeong Heonyeong, Yang Younghwan, Badloe Trevon, Rho Junsuk
Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea.
Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea.
Nanomaterials (Basel). 2022 Jan 1;12(1):153. doi: 10.3390/nano12010153.
In this work, we present metalenses (MLs) designed to enhance the luminous intensity of incoherent light-emitting diodes (LEDs) within the detection angles of 0° and 10°. The detection angle of 0° refers to the center of the LED. Because the light emitted from LEDs is incoherent and expressed as a surface light source, they are numerically described as a set of point sources and calculated using incoherent summation. The titanium dioxide (TiO) and amorphous silicon (a-Si) nanohole meta-atoms are designed; however, the full 2π phase coverage is not reached. Nevertheless, because the phase modulation at the edge of the ML is important, an ML is successfully designed. The typical phase profile of the ML enhances the luminous intensity at the center, and the phase profile is modified to increase the luminous intensity in the target detection angle region. Far field simulations are conducted to calculate the luminous intensity after 25 m of propagation. We demonstrate an enhancement of the luminous intensity at the center by 8551% and 2115% using TiO and a-Si MLs, respectively. Meanwhile, the TiO and a-Si MLs with the modified phase profiles enhance the luminous intensity within the detection angle of 10° by 263% and 30%, respectively.
在这项工作中，我们展示了用于在0°至10°检测角度范围内增强非相干发光二极管（LED）发光强度的超透镜（ML）。0°的检测角度指的是LED的中心。由于LED发出的光是非相干的，且表示为面光源，因此它们在数值上被描述为一组点光源，并使用非相干求和进行计算。设计了二氧化钛（TiO）和非晶硅（a-Si）纳米孔元原子；然而，并未实现完整的2π相位覆盖。尽管如此，由于ML边缘的相位调制很重要，因此成功设计了一种ML。ML的典型相位分布增强了中心处的发光强度，并且对相位分布进行了修改，以增加目标检测角度区域内的发光强度。进行了远场模拟，以计算传播25米后的发光强度。我们分别使用TiO和a-Si ML证明了中心处的发光强度增强了8551%和2115%。同时，具有修改后相位分布的TiO和a-Si ML在10°检测角度范围内分别将发光强度提高了263%和30%。
