Fast compressed sensing spectral measurement with adaptive gradient multiscale resolution

We propose a fast, adaptive multiscale resolution spectral measurement method based on compressed sensing. The method can apply variable measurement resolution over the entire spectral range to reduce the measurement time by over 75% compared to a global high-resolution measurement. Mimicking the characteristics of the human retina system, the resolution distribution follows the principle of gradually decreasing. The system allows the spectral peaks of interest to be captured dynamically or to b...     

弱光条件下的高分辨光谱测量

提出了一种基于数字微镜器件(DMD)和光电倍 增管(PMT)的弱光高分辨光谱测量 的新方法。 首先,利用基于小尺寸狭缝的分光光路将被测光光谱成像到DMD上,然后DMD微镜阵列按列依 次翻转 将光谱分波段投射到PMT点探测器上,最终实现对光谱的分时扫描测量。进行了与CCD光 谱仪的对 比实验以及不同弱光条件下的测试实验,并对系统的信噪比(SNR)特性进行了实验测试。实验结果表明,光谱测 量系统的谱分辨率高达0.23nm,灵敏度可达4.6pW以下,系统的信噪比(SNR)特性比较理想。相对于传 统的光谱 测量方法,本文方法具有成本低、易于实现且性能稳定等优点,在弱光高分辨光谱测量领域 具有较大的潜在应用价值。     

带压力保护的PID流量控制器

工业生产中的流量控制一般采用通用的PID控制器,这种方式的缺点是在控制流量的同时无法控制压力。为了能在控制流量的同时保证压力在允许的范围内,设计了一款带压力保护的流量控制器。该控制器同时采集流量和压力信号,当压力在允许范围内时,进行正常的流量控制。而当压力超标时,降低流量,从而降低压力,以保护设备。详细阐述了控制器的接口电路,并给出了PID算法和控制策略。     

Design and realization of high precision FBG rain gauge based on triangle cantilever beam and its performance research

A novel fiber Bragg grating (FBG) rain gauge is proposed in this paper to achieve high precision rainfall measurement. One core sensitive FBG, a temperature compensation FBG and a mechanical transition system construct this novel FBG rain gauge. Sensing principle of this FBG rain gauge is explained in detail, and its theoretical calculation model is also established, which shows that the relationship between center wavelength of sensitive FBG and external rainfall has very good linearity. To verify its detection performance, the calibration experiment on one prototype of this FBG rain gauge is carried out. After experiment data analysis, the detection precision of this FBG rain gauge is 15.4 μm which is almost two orders of magnitude higher than that of the existing rainfall measurement device. The experimental data confirm that this FBG rain gauge can achieve rainfall measurement with high precision.     

压缩感知光谱测量局部哈达玛矩阵的构造与性能

针对压缩感知光谱测量中随机矩阵作为测量矩阵无法获得高质量重建精度问题,提出了一种测量矩阵构造的新方法。介绍了局部哈达玛矩阵的构造方法,以随机测量矩阵为比较对象,通过仿真实验对局部哈达玛矩阵在压缩感知光谱测量中的性能进行分析。实验结果表明,相对于随机矩阵,新型局部哈达玛矩阵下的重建光谱与原始光谱重合度大大提高,在100%采样率时,定量指标MSE为3.2,实现了光谱的精确重建,25%采样率的MSE指标水平已经与随机矩阵100%采样率时相当,局部哈达玛矩阵可以有效的改善光谱重建的精度;光谱重建时间大约缩短到1/3,系统具有更好的信噪比特性。     

基于飞秒激光制备的光纤Fabry-Perot折射率传感器

在对光纤Fabry-Perot(F-P)传感器多光束干 涉原理仿真分析的基础上,利用波长为800nm的飞秒 激光脉冲在普通单模光纤(SMF)上制备微型传感器,并对其折射率响应性能进行了实验测试 。理论分析表明,在低、高折射率区域,F-P传感器的反射谱对比度随着折射率的增加分别 呈现先降低后增加的趋势(折射率高低分界点1．457)。飞秒激光 的制备方法通过计算机控制腔长等可以进行参数可选择的微型光纤F-P传感器的制作。利用 制备的传感器对一系列不同折 射率的溶液进行了折射率响应测试实验,测试结果表明,传感器反射谱对比度对低折射率物 质(折射率小于 1.457)的灵敏度为27.65dB/RI,对高折射 率 物质(折射率大于1.457)的灵敏度为3.50dB /RI,且均具有良好的线性响应。     

Compressive imaging based on multi-scale modulation and reconstruction in spatial frequency domain

Imaging quality is a critical component of compressive imaging in real applications. In this study, we propose a compressive imaging method based on multi-scale modulation and reconstruction in the spatial frequency domain. Theoretical analysis and simulation show the relation between the measurement matrix resolution and compressive sensing(CS)imaging quality. The matrix design is improved to provide multi-scale modulations, followed by individual reconstruction of images of different spatial frequencies. Compared with traditional single-scale CS imaging, the multi-scale method provides high quality imaging in both high and low frequencies, and effectively decreases the overall reconstruction error.Experimental results confirm the feasibility of this technique, especially at low sampling rate. The method may thus be helpful in promoting the implementation of compressive imaging in real applications.