排序方式: 共有63条查询结果,搜索用时 0 毫秒
51.
在无波形发生器的情况下,利用可变衰减器或整形DANTE脉冲序列的方法可实现选择激发,通过在UNITY-400 NMR谱仪上进行的选择激发实验,比较了这两种方法的适用性,结果表明,整形DANTE脉冲序列的方法,应用灵活,方便,不需要对谱仪的硬件作任何改动,并且选择激发的轮廓更接近于理想的情况,若激发谱宽范围较大(>1000Hz),建议采用快速变换衰减器衰减幅度的方法,若激发谱宽范围较小(<1000H 相似文献
52.
直角棱镜激光衰减器的研究与实验 总被引:1,自引:0,他引:1
本文在分析平面反射和棱镜内光束传输规律的基础上,提出以直角棱镜用做无像差激光衰减器,并在宽、窄He Ne光束条件下,通过对激光光束质量因子M2的测量,验证棱镜反射应用衰减器对光束质量无显著影响。 相似文献
53.
54.
55.
This study proposes a new hybrid Mach-Zehnder interferometric(MZI) sensor based on two core-offset attenuators and an abrupt taper in a single-mode fiber fabricated by a fiber-taper machine and electric arc discharge. When the distance between the two core-offset attenuators is stretched to 4500 μm, significant interference signals are detected with a prominent attenuation peak of ~28 dB. The proposed MZI can be used to measure temperature due to its low refractive index(RI) and strain cross-sensitivity. The temperature sensitivity is 34.95±0.04 and 106.70±0.04 pm/℃ in the temperature ranges of 14-250 and250-1000 ℃, respectively. 相似文献
56.
利用电控改变固液界面湿润角的电润湿微棱镜(EMPs)技术以及双自聚焦透镜组合设计了一类新颖的可调光衰减器,并对该衰减器的衰减性能进行了原理分析和实验测量.理论分析和实验结果表明其具有良好的光衰减控制效应,在不大的电压变化范围(例如135—139V)内即可实现2—60dB的光衰减范围.该器件构思新颖,具有结构简单、容易制作的优点,经过优化后将会在光通信领域得到广泛的应用.缺点是工作电压偏高,需要进一步筛选出介电系数高的物质来作为介电绝缘层材料,以便降低工作电压,达到实际可以使用的目的.
关键词:
微流控光学
电湿效应
可调光衰减器
电润湿微棱镜 相似文献
57.
58.
59.
Low Power-Consumption and High Response Frequency Thermo-Optic Variable Optical Attenuators Based on Silicon-on-Insulator Materials 总被引:1,自引:0,他引:1 下载免费PDF全文
A novel silicon-on-insulator thermo-optic variable optical attenuator with isolated grooves based on a multimode interference coupler principle is fabricated by the inductive coupled plasma etching technology. The maximum fibre-to-fibre insertion loss is lower than 2.2 dB, the dynamic attenuation range is from 0 to 30 dB in the wavelength range 1500-1600nm, and the maximum power consumption is only 140roW. The response frequency of the fabricated variable optical attenuator is about 30kHz. Compared to the variable optical attenuator without isolated grooves, the maximum power consumption decreases more than 220roW, and the response frequency rises are more than 20 kHz. 相似文献
60.