红外与激光工程
2021, 50(1): 20211004
Author Affiliations
Abstract
1 School of Electronic Engineering, Beijing University of Posts and Telecommunications, Beijing 100876, China
2 School of Information, Beijing University of Technology, Beijing 100124, China
3 Institute of Laser Engineering, Beijing University of Technology, Beijing 100124, China
Flexible light-emitting diodes (LEDs) are highly desired for wearable devices, flexible displays, robotics, biomedicine, etc. Traditionally, the transfer process of an ultrathin wafer of about 10–30 μm to a flexible substrate is utilized. However, the yield is low, and it is not applicable to thick GaN LED chips with a 100 μm sapphire substrate. In this paper, transferable LED chips utilized the mature LED manufacture technique are developed, which possesses the advantage of high yield. The flexible LED array demonstrates good electrical and optical performance.
Journal of Semiconductors
2020, 41(3): 032302
Author Affiliations
Abstract
1 School of Electronic Engineering, State Key Laboratory for Information Photonics and Optical Communications, Beijing Key Laboratory of Work Safety Intelligent Monitoring, Beijing University of Posts and Telecommunications, Beijing 100876, China
2 School of Information, Beijing University of Technology, Beijing 100124, China
3 Institute of Laser Engineering, Beijing University of Technology, Beijing 100124, China
Broadband and omnidirectional antireflection coating is generally an effective way to improve solar cell efficiency, because the destructive interference between the reflected and incident light can maximize the light transmission into the absorption layer. In this paper, we report the incident quantum efficiency ηin, not incident energy or power, as the evaluation function by the ant colony algorithm optimization method, which is a swarm-based optimization method. Also, SPCTRL2 is proposed to be incorporated for accurate optimization because the solar irradiance on a receiver plane is dependent on position, season, and time. Cities of Quito, Beijing and Moscow are selected for two- and three-layer antireflective coating optimization over λ = [300, 1100] nm and θ = [0°, 90°]. The ηin increases by 0.26%, 1.37% and 4.24% for the above 3 cities, respectively, compared with that calculated by other rigorous optimization algorithms methods, which is further verified by the effect of position and time dependent solar spectrum on the antireflective coating design.
Journal of Semiconductors
2019, 40(3): 032702
1 北京工业大学 信息学部, 北京 100124
2 北京邮电大学 电子工程学院 信息光子学与光通信国家重点实验室, 北京 100876
对Si基PIN光电探测器的电场隔离结构进行了研究, 讨论了电场隔离结构的作用以及其与暗电流的关系, 并进行了仿真模拟与测试分析。电场隔离结构主要将有源区和边缘隔离从而降低暗电流, 结合仿真模拟结果和实验测试结果, 分析得到电场隔离结构主要降低与周长有关的暗电流, 对于小尺寸器件作用更明显。
Si基光电探测器 电场隔离结构 暗电流 Si photodetector isolation ring leakage current
Author Affiliations
Abstract
1 Photonic Device Research Laboratory, College of Electronic Information and Control Engineering, Beijing University of Technology, Beijing 100124, China
2 College of Physics and Electronic Information, Gannan Normal University, Ganzhou 341000, China
Two-dimensional apodized grating couplers are proposed with grating grooves realized by a series of nano-rectangles, with the feasibility of digital tailoring the equivalent refractive index of each groove in order to obtain the Gaussian output diffractive mode in order to enhance the coupling efficiency to the optical fiber. According to the requirement of leakage factor distribution for a Gaussian output profile, the corresponding effective refractive index of the grating groove, duty cycle, and period are designed according to the equivalent medium theory. The peak coupling efficiency of 93.1% at 1550 nm and 3 dB bandwidth of 82 nm are achieved.
050.2770 Gratings 050.6624 Subwavelength structures 050.2065 Effective medium theory Chinese Optics Letters
2015, 13(5): 050501
1 湖南航天远望测控技术有限公司, 湖南 长沙 410205
2 中国航天科工集团7801研究所, 湖南 长沙 410205
介绍了温度场和应力引起光纤陀螺误差的机理, 通过对光纤陀螺的结构细分, 采用不同材料分别建立有限元模型, 进行模态分析、热应力分析和瞬态温度分析, 选取具有代表性的新型材料铍铝合金和因瓦合金与传统铝合金进行对比。结果表明, 铍铝合金可以提高光纤陀螺的固有频率, 同时提高光纤陀螺的温度性能, 因瓦合金可以大幅度降低光纤陀螺光纤线圈的应力变化, 将光纤陀螺结构细分, 进行材料优选, 可以显著提高光纤陀螺的温度性能和动态输出精度, 并得到试验论证。
光纤陀螺 有限元 结构材料 温度性能 动态性能 fiber optic gyroscope(FOG) finite element structural materials temperature performance dynamic output precision