Author Affiliations
Abstract
1 School of Electronic and Information Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China
2 International Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
3 Shenzhen Vivolight Medical Device & Technology Co., Ltd., Shenzhen 518055, China
4 State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an 710119, China
5 Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
6 Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong, China
Current gradient-index (GRIN) lens based proximal-driven intracoronary optical coherence tomography (ICOCT) probes consist of a spacer and a GRIN lens with large gradient constant. This design provides great flexibility to control beam profiles, but the spacer length should be well controlled to obtain desired beam profiles and thus it sets an obstacle in mass catheter fabrication. Besides, although GRIN lens with large gradient constant can provide tight focus spot, it has short depth of focus and fast-expanded beam which leads to poor lateral resolution for deep tissue. In this paper, a type of spacer-removed probe is demonstrated with a small gradient constant GRIN lens. This design simplifies the fabrication process and is suitable for mass production. The output beam of the catheter is a narrow nearly collimated light beam, referred to as pencil beam here. The full width at half maximum beam size varies from 35.1 μm to 75.3 μm in air over 3-mm range. Probe design principles are elaborated with probe/catheter fabrication and performance test. The in vivo imaging of the catheter was verified by a clinical ICOCT system. Those results prove that this novel pencil-beam scanning catheter is potentially a good choice for ICOCT systems.
optical coherence tomography endoscopic imaging intravascular imaging fiber optics imaging 
Opto-Electronic Advances
2022, 5(3): 200050
作者单位
摘要
哈尔滨工业大学深圳研究生院, 广东 深圳 518055
三次谐波产生(THG)与三光子参量下转换(TPDC)由于频率跨度大,相位匹配条件很难实现。波导模式色散是有效补偿材料色散的工具。但是THG或TPDC的非线性极化强度为奇函数,如果模场分布存在正负分布,则奇函数几乎为0。提出非对称等离子体沟道波导设计,沟道中引入高阶非线性有机材料(DDMEBT)。晶体硅(Si)在沟道底部以破坏波导的对称性。金属包层采用损耗较小的银(Ag)。通过设计波导几何参数,在基频(FF)零阶模式和第三次诣波(TH)一阶模式间获得了有效的相位匹配条件(PMC),相应THG或TPPC的重叠积分远高于对称波导情况。
非线性光学 参量下转换 等离子体沟道波导 相位匹配 模式色散 
光学学报
2015, 35(s1): s119002
Author Affiliations
Abstract
Department of Electronic and Information Engineering, Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055, China
A novel closed-form expression for average capacity is derived for free-space optical (FSO) links over Gamma-Gamma turbulence channels by considering the effect of misalignment (pointing errors). The simulation results show that the average capacity of the FSO links can be analyzed with the effects of atmospheric turbulence condition, beam width, detector size, jitter variable, and transmitted optical power. Meanwhile, the results are further provided to verify the accuracy of our mathematical analysis. This work is useful for the FSO designer.
自由空间光通信 大气湍流 Gamma-Gamma分布 平均容量 瞄准误差 010.1300 Atmospheric propagation 010.1330 Atmospheric turbulence 060.4510 Optical communications 
Chinese Optics Letters
2010, 8(6): 537
作者单位
摘要
1 哈尔滨工业大学 深圳研究生院电子与信息工程学科部,广东 深圳 518055
2 哈尔滨工业大学 可调谐(气体)激光技术国家级重点实验室,黑龙江 哈尔滨 150001
利用非线性偏振旋转效应可在能量对称的非线性光纤环镜中获得强度相关损耗输出,具有该特性的非线性光纤环镜可作为强度均衡器来抑制室温条件下的掺铒光纤中的模式竞争。对这种环镜在多波长掺铒光纤激光器中的应用进行了研究,分析了入射偏振态和环镜内双折射对非线性光纤环镜输出特性的影响,研究了激光腔内光场的偏振条件以及对多波长激光系统的作用,并在L波段获得了3 dB范围内13条波长输出,波长间隔为1 nm,单波长半个小时内的功率波动小于0.6 dB。通过调整非线性光纤环镜引入的强度相关损耗的大小可以控制多波长的数目和频谱位置。
光纤光学 激光器 非线性偏振旋转 非线性光纤环镜 多波长 
光学学报
2010, 30(3): 787
作者单位
摘要
哈尔滨工业大学深圳研究生院激光信息技术研究中心, 广东 深圳 518055
自由空间光通信(FSO)在开放的大气链路中传输光信号, 不可避免地会受到大气扰动和背景光噪声的影响, 导致系统的可靠性降低。为了抑制大气扰动等对FSO系统造成的不利影响, 提出一种新的光信号调制方式——圆偏振位移键控(CPOLSK)。该调制方式利用圆偏振光的两种旋光状态进行数据的传送, 接收端结合差分方法进行光信号接收。给出了CPOLSK的装置模型, 并对其性能进行了分析。与目前广泛采用的开关键控(OOK)、脉冲位置调制(PPM)方式相比, CPOLSK很好地抑制了背景光噪声的影响, 同时对光电探测器内部噪声也有一定的抑制效果。
光通信 自由空间光通信 大气扰动信道 偏振位移键控 误码率 
光学学报
2008, 28(s2): 223

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