基于双金属和FP干涉结构的光纤温度传感器

为了提高现有光纤温度传感器的灵敏度和测温范围,提出了一种基于双金属和法布里—珀罗(FP)干涉结构的传光型光纤温度传感器。以双金属片作为感温元件,利用部分反射镜和双金属片作为上、下表面,构成FP腔,采用调频激光干涉原理测量感温元件受热产生的FP腔腔长变化量,实现对温度的传感。实验结果表明:制成的光纤温度传感器的腔长变化量与温度呈较好的线性关系,线性度为99.96%,温度测量灵敏度达到了3885nm/℃,重复性高。

Surface Plasmon Interference Lithography Assisted by a Fabry-Perot Cavity Composed of Subwavelength Metal Grating and Thin Metal Film

A surface plasmon interference lithography assisted by a Fabry-Perot （F-P） cavity composed of subwavelength metal gratings and a thin metal fihn is proposed to fabricate high-quality nanopatterns. The calculated results indicate that uniform straight interference fringes with high contrast and high electric-field intensity are formed in the resist under the F-P cavity. The analyses of spatial frequency spectra illuminate the physical mechanism of the formation for the interference fringes. The influence of the F-P cavity spacing is discussed in detail. Moreover, the error analyses reveal that all parameters except the metal grating period in this scheme can bear large tolerances for the device fabrication.

非本征型FP干涉光纤传感器的膜片性能研究

针对膜片材料参数对膜片形变式非本征型法布里—珀罗(FP)干涉光纤传感器性能的影响,研究了石英玻璃和单晶硅(100)膜片非本征FP干涉光纤传感器,用于中低压环境的测量。选定膜片材料有效半径425~500μm,厚度10~30μm,通过MATLAB对不同材料的膜片进行仿真分析,研究了石英玻璃和单晶硅(100)膜片的主要参数有效半径、厚度对灵敏度与动态压力信号频率响应的影响。仿真结果表明:石英玻璃和单晶硅(100)都有比较适中的灵敏度和响应频率,在膜片有效半径和厚度相同的情况下,石英玻璃的灵敏度要高于单晶硅(100)的,而单晶硅(100)的频率响应高于石英玻璃。通过激光焊接石英玻璃膜片的FP干涉传感器,有效半径为500μm,厚度为30μm时,压力灵敏度的实测结果为5.77 nm/kPa,与仿真结果基本吻合。

Effective transmittance of Fabry–Perot cavity under non-parallel beam incidence

The Fabry–Perot(FP) resonant cavity is widely used in laser and spectroscopic measurements due to its unique interference transfer function(ITF). In the ideal case of parallel incident light, the ITF of the FP resonant cavity can be expressed by the Airy function. However, in reality, it is difficult to achieve perfect parallelism with collimated beams. In this article, a theoretical model is established for non-parallel light incidence, which assumes that the non-parallel incident light is a cone-shaped beam, and the cone angle is used to quantify the non-parallelism of the beam. The transmittance function of the FP resonant cavity under non-parallel light incidence is derived. The accuracy of the model is experimentally verified. Based on this model, the effects of divergence angle, tilt angle and FP cavity parameters(reflectivity, cavity length)on the ITF are studied. The reasons for the decrease in peak value, broadening and asymmetry of the interference peak under non-parallel light incidence are explained. It is suggested that a fine balance between the interference peak and the collimation effect of the incident light should be considered in the design and application of FP resonant cavities, especially for tilted applications such as angle-scanned spectroscopy. The research results of this article have certain significance for the design and application of FP resonant cavities.

基于FPGA的可调谐光纤激光器频率锁定控制电路

根据PDH(Pound-Drever-Hall)稳频技术原理设计了基于FPGA的可调谐光纤激光器频率锁定控制电路,利用Matlab/Simulink建立频率误差信号解调电路模型,仿真结果表明能够输出频率误差信号。以FPGA为核心控制A/D采集光电探测器探测的信号,结合DDS(Direct Digital Synthesizer)技术在FPGA内部实现混频和低通滤波的功能,实验结果与仿真结果相符,能够解调出光纤激光器输出激光的频率锁定误差信号。根据此误差信号调节反馈电压,改变受压电陶瓷调谐的有源相移光纤光栅峰值谐振波长,实现对激光器的频率锁定,为光纤激光器稳频系统的集成化奠定了基础。

基于FP增长算法的红外抗干扰评估指标简约方法

针对红外抗干扰评估指标体系存在的冗余现象和缺乏合理性的特点,从红外导引头的固有属性、抗干扰性能指标以及导弹战技性能指标3个角度构建红外抗干扰综合评估指标,通过红外抗干扰实验仿真平台,设置相应干扰量,获取海量数据并对其进行预处理;再利用数据挖掘中的FP增长关联规则算法,对数据进行挖掘分析,得出干扰量与指标之间的关联规则;然后通过这些关联规则的强弱对指标进行简约,去除了冗余项仅保留了核心指标;最后采用BP神经网络对简约后的指标进行了有效性检验,结果验证方法下获取的抗干扰指标更为简洁、高效。

Investigations and prospects of Fabry-Perot antennas:a review

Fabry-Perot(FP)antennas have characteristics of planar structures combined with high gain,and they have been widely used in wireless communications.With the progress of ongoing research,FP antennas have achieved various capabilities,but many of them are still under development,such as lowprofile,wideband,circular polarization,multi-band,low-radar cross section(RCS)and reconfigurable features.This paper discusses the theoretical analysis methods and research progress of FP antennas,and explains the realization methods of different features of FP antennas.In order to indicate different technologies for realizing various capabilities,the key technologies and features of some of the latest designs are described.Finally,the research situation and prospects of FP antennas are summarized to guide their research directions in the future.

Mesa Diaphragm-Based Fabry-Perot Optical MEMS Pressure Sensor

An optical micro electron mechanical system （MEMS） pressure sensor with a mesa membrane is presented. The operating principle of the MEMS pressure sensor is expatiated by the Fabry-Perot （F-P） interference and the relation between deflection and pressure is analyzed. Both the mechanical model of the mesa structure diaphragm and the signal averaging effect is validated by simulation, which declares that the mesa structure diaphragm is superior to the planar one on the parallelism and can reduce the signal averaging effect. Experimental results demonstrate that the mesa structure sensor has a reasonable linearity and sensitivity.

基于频率选择表面的太赫兹FP干涉滤光片设计

在太赫兹频段,为解决FP干涉滤光片反射率低、适用频率范围小及角度稳定性差的问题,设计了一种新的太赫兹频率选择表面结构。首先进行了仿真分析,确定了结构的硅片厚度和金属网栅层数,并对参数进行了优化。然后对该结构的传输特性和角度稳定性进行了仿真,该结构在入射倾斜角0°~45°范围内具有较好的稳定性,最后加工出滤光片实物,对仿真结果的准确性进行验证。在太赫兹波垂直入射的情况下,实物测量结果与仿真结果基本吻合,在1.34~2.34 THz频率范围内,反射率和透射率分别为91.0%~98.4%和0.7%~8.0%,满足FP干涉滤光片高反射率、低透射率要求。

FP传感器双峰级次腔长解调算法

在应用双峰法解调光纤法布里-珀罗(Fabry-Perot, FP)传感器时,由于难以准确判断干涉级次,而导致解调腔长误差明显过大。为了应对这种问题,提出一种双峰级次腔长解调算法。该算法通过跟踪传感器反射光谱中相距最远的两个波峰准确判断出所选波峰的干涉级次,然后根据单峰法精确解算出绝对腔长。由于有效消除了双峰法的干涉级次模糊,腔长解算精度显著提高。对腔长30—100μm的FP传感器进行了仿真分析和验证实验。仿真解调误差小于0.7 nm,实验误差小于1.4 nm,解调误差远小于双峰法。

Fabry-Perot interference and piezo-phototronic effect enhanced flexible MoS_(2) photodetector

Flexible photodetectors(PDs)are indispensable components for next-generation wearable electronics.Recently,two-dimensional(2D)materials have been implemented as functional flexible optoelectronic devices due to their characteristics of atomically thin layers,excellent flexibility,and strain sensitivity.In this work,we developed a flexible photodetector based on MoS_(2)/NiO heterojunction,and Fabry-Perot(F-P)and piezo-phototronic effect have been employed to enhance the responsivity(R)and external quantum efficiency(EQE)of the devices.The F-P effect is utilized to improve the optical absorption of the MoS_(2),resulting in an enhancement in the photoluminescence(PL)of monolayer MoS_(2) and the EQE of the photodetector by 30 and 130 times,respectively.The flexible photodetector exhibits an ultrahigh detectivity(D*)of 2.6×10^(14) Jones,which is the highest value ever reported for flexible MoS_(2) PDs.The piezo-potential of monolayer MoS_(2) decreases the valence band offset at the interface of MoS_(2)/NiO,which increases the transfer efficiency of the photon-generated carriers significantly.Under 1.17%tensile strain,the R of the flexible photodetector can be enhanced by 271%.This research may provide a universal strategy for the design and performance optimization of 2D materials heterostructures for flexible optoelectronics.

多处理器固定优先级算法的可调度性分析

针对多处理器实时调度中的固定优先级(FP)调度算法,提出了一种改进的可调度性判定方法。引入Baruah的最早截止期优先(EDF)窗口分析框架,将高优先级任务带入作业的最大数量限定为m-1(m为处理器个数),进而对任务的干涉上界进行重新界定,并由此得到一个更加紧密的可调度性判定充分条件。仿真实验结果表明,该方法增加了通过判定任务集的数量,体现出更优的可调度判定性能。

Using Brillouin fiber-optic ring laser to provide base station with uplink optical carrier in a 10 GHz radio over fiber system

In this paper, a 10 GHz radio over fiber system is analyzed. The Brillouin fiber-optic ring laser is used in the center station （CS） to suppress the optical carrier for the modulation depth enhancement. Simultaneously, the Stockes wave induced by the Brillouin amplification injects and locks the Fabry-Perot （FP） laser to output a signal-mode optical source, which works as the uplink optical carrier.

法布里—珀罗干涉仪在现代光学中的应用

十九世纪未由法布里和珀罗研制出了多光束干涉仪,简称E—P干涉仪。由于它在近代物理和现代物理中具有非常重要的应用价值,因此在国内外的光学教材中都进行了专门论述,并详细地介绍了它的应用。它的特殊价值在于:它是一种分辨本领极高的光谱仪器,可精确地比较各光谱线的波长,用于光谱线超精细结构的研究;其次它还是现代激光器的谐振腔;以及在光学仪器中作为干涉滤光片。

Compact and high-efficient wavelength demultiplexing coupler based on high-index dielectric nanoantennas

Wavelength demultiplexing waveguide couplers have important applications in integrated nanophotonic devices. Two of the most important indicators of the quality of a wavelength demultiplexing coupler are coupling efficiency and splitting ratio. In this study, we utilize two asymmetric high-index dielectric nanoantennas directly positioned on top of a silicon-on insulator waveguide to realize a compact wavelength demultiplexing coupler in a communication band, which is based on the interference of the waveguide modes coupled by the two nanoantennas. We add a Au substrate for further increasing the coupling efficiency. This has constructive and destructive influences on the antenna＇s in-coupling efficiency owing to the Fabry-Perot（FP） resonance in the SiO2 layer. Therefore, we can realize a wavelength demultiplexing coupler with compact size and high coupling efficiency. This coupler has widespread applications in the areas of wavelength filters,on-chip signal processing, and integrated nanophotonic circuits.

A novel time-to-live countdown scheme based on asymmetric Mach-Zehnder interferometer and Fabry-Perot semiconductor optical amplifier

We propose a novel optical time-to-live （TTL） processing scheme using asymmetric Mech-Zehnder inter-ferometer （AMZI） and Fabry-Perot semiconductor optical amplifier （FP-SOA）. AMZI transfers M TTL pulses into M-1 pulses and two residual pulses with 6-dB power difference. FP-SOA enhances the power difference between the M - 1 pulses to the residual pulses to more than 10 dB. A numerical model is established for verifying the feasibility of this scheme.

改善全彩LED显示屏对比度的选择性滤光片设计方法

环境杂散光会显著降低LED显示屏的对比度,本文提出在全彩屏前增加一个干涉滤光片的方法,选择性地透过RGB三色光,杂散光却被反射,从而提高显示屏的对比度。文章提出了RGB发射峰的数学模型和滤光片设计的评价函数,给出了详尽的设计方法、步骤和一个例子的设计结果。

基于重叠写入啁啾光栅的Fabry-Perot腔的研究

以两段重叠写入的啁啾光栅作为反射面,构成光纤光栅Fabry-Perot(FP)腔。分别采用施加应力法和移动相位掩模板法,在同一段光纤中重叠写入啁啾光栅形成FP腔。使用啁啾量为1nm的相位掩模板进行实验,两种方法曝光后的重叠啁啾光栅都可以形成明显梳状透射光谱。使用移动相位掩模板法,透射光谱的自由光谱范围(FSR)可达0.6 nm。以耦合模理论为基础,用龙格库塔迭代法进行仿真,重叠写入啁啾量为3 nm的啁啾光栅后可形成FSR超过1.3 nm的梳状透射光谱。试验及仿真表明重叠写入啁啾光栅用作FP腔滤波器的可行性,为FP腔的研究提供了新方向。

All-Optical Switching Using Fabry-Perot Laser Diodes (Invited paper)

In this paper, we investigate all-optical packet switching using a multi-wavelength mutual injection-locked Fabry-Perot laser diode. We observe error-free packet-switching of a 10 Gb/s signal with an extinction ratio of 16.9.

A Tunable Dual-Wavelength Fiber Ring Laser with a Fabry-Perot Laser Diode in an External Injection Seeding Scheme

A tunable dual-wavelength fiber ring laser with a Fabry-Perot laser diode is proposed and demonstrated. The dual-wavelength outputs have the optical side-mode-suppression-ratio (SMSR) over 31 dB. The wavelength tuning range can be up to 9 run.