High-strained InGaAs/InGaAsP multiple quantum wells (MQWs) distributed feedback (DFB) lasers, fabricated using metal organic chemical vapor deposition, are presented at 1.82 \mu m with a high side-mode-suppression ratio of 49.53 dB. The current- and temp
We propose a novel methodology based on the projector-camera (ProCam) system to address the photometric compensation issue for the projection display on the patterned screen.The patterned screen is treated as the combination of a perfect white screen and
A kind of fiber-optic sensor for simultaneous measurement of refractive index of surrounding medium, temperature and strain is described. Based on core diameter mismatch, a multimode-single mode-multimode (MSM) structure is presented. It is demonstrated t
给出了脉冲展宽/压缩比与线性啁啾量之间的关系式,然后通过对放大过程中脉冲宽度和啁啾量变化情况的分析,得到了啁啾脉冲放大后最窄脉冲宽度的解析表达式。与实际报道的实验的比较表明该理论是简明而极其有效的。
基于S波片和双延迟器的偏振特性, 提出了一种矢量光场的生成及偏振调控方法, 该方法能够将标量高斯光束转换为偏振态分布可调谐的矢量光束。结合Stokes-Mueller矩阵算法, 建立了矢量光场偏振调控的数学模型, 并仿真计算出标量高斯光束经过S波片和双延迟器(包括双1/4波片和双1/2波片两种情况)后的偏振态空间分布。讨论了双延迟器相对旋转时光场偏振分布的演化规律及机理, 实验结果与数值仿真结果相互吻合, 表明该方法可以实现对标量相干光场的复杂偏振调控, 验证了理论分析的正确性和该方法的可行性。
The finite-difference time-domain method was employed to calculate light extraction efficiency of thin-film flip-chip InGaN/GaN quantum well light-emitting diodes (LEDs) with TiO2 microsphere arrays. The extraction efficiency for LEDs with microsphere arr
We demonstrate an all-fiber, high-power, and high stability ultrafast laser source operating at 1563 nm. A highly stable, self-starting carbon nanotube (CNT) mode-locked femtosecond fiber laser is used as the seed source. The amplifier stage uses a fiber
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