The effect of the reduction of intensity noise by electronic feedback on the frequency stability of a GaAlAs laser is investigated. Only a small increase (approximately 30%) in stability was observed because the intensity and frequency noise were found to be not completely correlated. The technique described can also be used to estimate the coherence function gamma2 between the various noise properties of the laser's emission without using a correlator.
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http://dx.doi.org/10.1364/ao.22.000310 | DOI Listing |
Anal Chem
January 2025
School of Electrical Engineering, Yanshan University, Qinhuangdao 066004, China.
As breath nitric oxide (NO) is a biomarker of respiratory inflammation, reliable techniques for the online detection of ppb-level NO in exhaled breath are essential for the noninvasive diagnosis of respiratory inflammation. Here, we report a breath NO sensor based on the multiperiodic spectral reconstruction neural network. First, a spectral reconstruction method that transforms a spectrum from the wavelength domain to the intensity domain is proposed to remove noise and interference signals from the spectrum.
View Article and Find Full Text PDFAcross the scientific realm, we find ourselves subtracting or dividing stochastic signals. For instance, consider a stochastic realization, $x$, generated from the addition or multiplication of two stochastic signals $a$ and $b$, namely $x=a+b$ or $x = ab$. For the $x=a+b$ example, $a$ can be fluorescence background and $b$ the signal of interest whose statistics are to be learned from the measured $x$.
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View Article and Find Full Text PDFFor indirect time-of-flight (iToF) cameras, we proposed a modeling approach focused on addressing random error. Our model characterizes random error comprehensively by detailing the propagation of error introduced by signal light, ambient light, and dark noise through phase calculation and system correction processes. This framework leverages correlations between incident light and tap responses to quantify noise impacts accurately.
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