针对目前常见广义椭偏仪变角结构多采用双电机驱动,且存在结构复杂、变角后光路存在偏离等问题,论文提出一种单电机驱动广义椭偏仪新的变角结构。该结构采用固定起偏臂,利用同步齿轮传动单电机驱动方式使载物台和检偏臂同步旋转,实现椭偏仪多角度测量。在传统卧式结构广义椭偏仪变角结构基础上,设置样品载物台和检偏臂1∶2同步传动,并通过Inventor运动仿真验证了本结构的可行性。论文提出的单电机驱动变角结构变角后不仅维持了变角前后的准直,而且其整体结构简单,极大地优化了椭偏仪变角的复杂度,在广义椭偏仪工程化进程中有比较重要的应用价值。
This paper presents a surface plasmon resonance (SPR) sensor based on a flattened plastic optical fiber (POF) for refractive index (RI) sensing. The flattened POF is fabricated by mechanical hot pressing. Afterwards, a thin film of Ag and Au is first deposited on one side of the flat surface to excite the SPR effect. The results show that the flattened POF-based SPR probe coated with the Au film has a sharper SPR peak and a narrower peak width than the probe coated with Ag film. To improve the SPR effect, two flat surfaces of the flattened POF are coated with metal film (Ag and Au). It was found that the sensor showed better RI sensing performance compared to the sensor with only one flat surface coated with metal film. For the flattened POF with two flat surfaces coated with Ag film, achieving the highest RI sensitivity of 2507 nm/RIU in the RI range of 1.33–1.39. The proposed sensor is a low-cost solution for RI measurement with potential applications in the medical and biochemical fields.
针对目前双伺服电机控制补偿器旋转的椭偏测量技术中电机同步旋转控制复杂,且探测器同步信号触发采集困难、长时间运行稳定性差等缺点.提出一种基于单电机驱动的双相位补偿器旋转结构以及控制方法.该结构中与伺服电机连接的同步齿轮的直径比为5∶3,不同的齿轮直径是为实现对双旋转补偿器的差速控制,结合双旋转补偿器椭偏测量理论,实现样品的多维度信息获取;且基于控制理论设计伺服电机驱动电路和信号触发采集电路,完成相关硬件方面设计.最终实现系统在长时间运行过程中补偿器转速稳定可控,一次测量可得穆勒矩阵16个参数,为椭偏测量样品各维度信息提供理论依据及技术支撑.
交换机在医院信息管理系统中中占有重要的地位,其最主要的功能就是转发数据,能在黑客攻击和病毒侵扰下,保持其高效的数据转发速率.其次,交换机作为整个网络的核心,具有访问和存取网络信息的用户进行区分和权限控制,再次交换机还能在配合其他网络安全设备的前提下,对非授权访问和网络攻击进行监控和阻止.可见交换机的正常运转直接影响到医院数据信息的安全使用,笔者就交换机常见工作故障及其对策以及交换机实用日常维护三方面加以分析和讨论.