Optical Engineering + Applications最新文献_第7页

Investigating the impact of ghost images on the accuracy of modulation transfer function measurement using knife-edge method 研究了虚像对刀口法测量调制传递函数精度的影响

Optical Engineering + Applications Pub Date : 2023-10-04 DOI: 10.1117/12.2676634

D. Ryu, Seonghui Kim, S. Seong, Hyunju Seo, Y. Youk, Goeun Kim, Shinwook Kim, Jeeyeon Yoon, Deog Gyu Lee, H. Heo

{"title":"Investigating the impact of ghost images on the accuracy of modulation transfer function measurement using knife-edge method","authors":"D. Ryu, Seonghui Kim, S. Seong, Hyunju Seo, Y. Youk, Goeun Kim, Shinwook Kim, Jeeyeon Yoon, Deog Gyu Lee, H. Heo","doi":"10.1117/12.2676634","DOIUrl":"https://doi.org/10.1117/12.2676634","url":null,"abstract":"In this study, we investigated the impact of ghost images on the modulation transfer function (MTF) of a Korsch-type telescope using nonsequential ray-tracing simulations and the experimental measurements of the knife-edge method with a collimator and light source targets. Our findings showed that ghost images introduce a directional bias into the edge spread function depending on the field position, which affects the line spread function and MTF. Furthermore, our measurement results demonstrated that ghost images can significantly affect the MTF on the edge field of the green channel. The ghost-to-signal ratio in the multispectral (MS) green channel was approximately 2.5%, which is approximately 0.25% higher than that in the panchromatic channel. To estimate the impact of ghost images in the MS green channel, we performed a parametric analysis using a nonsequential ray-tracing simulation, exploring potential strategies, such as adjusting the window thickness, the distance between the detector and the window, the transmittance of the window surface, and the reflectance of the detector surface. By comparing the positions and intensities of the ghost images obtained from the simulations with those measured experimentally, we identified the simulation input parameters that best reproduced the measured results. Our study provides valuable insight into the importance of managing ghost images when designing and operating Korsch-type telescopes to achieve the optimal image quality.","PeriodicalId":434863,"journal":{"name":"Optical Engineering + Applications","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131387732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Neural network analog of the ICP algorithm 神经网络模拟的ICP算法

Optical Engineering + Applications Pub Date : 2023-10-04 DOI: 10.1117/12.2676383

S.Yu. Leonov, A. Vasilyev, A. Makovetskii, Egor Gordionok, V. Kober

{"title":"Neural network analog of the ICP algorithm","authors":"S.Yu. Leonov, A. Vasilyev, A. Makovetskii, Egor Gordionok, V. Kober","doi":"10.1117/12.2676383","DOIUrl":"https://doi.org/10.1117/12.2676383","url":null,"abstract":"The paper deals with the problem of overlapping two point-data clouds. Traditionally, iterative or variational methods are used to solve such problems. However, these methods are ineffective to solve tasks with a large number of points in the clouds or in the cases of task series with real-time cloud mapping. For those tasks, it is more appropriate to use neural network technique and deep learning methods. The overlap of point-data clouds is understood as finding the displacement vector between them and the rotation matrix of the clouds relative to each other. First of all, point-data clouds are reduced to the zero displacement by means of some transformation. To find the rotation matrix for transformed clouds the authors proposed a simple neural network implementation of the ICP algorithm. This implementation consists of two stages substantially formed by neural networks. At the first stage, a two-layer probabilistic network acts as a metric classifier. The first layer of the probabilistic network is composed of radial-basis elements – Gaussians. The Gaussian activation function makes it possible to identify the output of the first layer with the probability showing the proximity of the points of the superimposed clouds. The second layer of this network is competitive. As a result of the probabilistic network, the points of these two clouds are ranked according to the degree of proximity. The point-data clouds sorted by proximity are sent to the second single-layer neural network. On the second stage, the rotation matrix is calculated using the learning procedure according to the Hebb rule. In the case of small point clouds (less than 10 thousand points), it is more appropriate to use a pseudo-inverse rule (calculations using a pseudoinverse Penrose-Moore matrix) based on the Hebb rule. At the output of the second stage, the rotation matrix is obtained, with which we can easily calculate the displacement vector of the original point clouds. The approbation of the proposed point-data cloud overlap method showed a good match on samples from the ModelNet40 database.","PeriodicalId":434863,"journal":{"name":"Optical Engineering + Applications","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114164465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Hopping discrete cosine transform 跳频离散余弦变换

Optical Engineering + Applications Pub Date : 2023-10-04 DOI: 10.1117/12.2677172

V. Kober, J. González-Fraga, A. Kober

引用次数: 0

Remote physiological monitoring of neck blood vessels 颈部血管的远程生理监测

Optical Engineering + Applications Pub Date : 2023-10-04 DOI: 10.1117/12.2680679

Meiyun Cao, Gennadi Saiko, T. Burton, A. Douplik

{"title":"Remote physiological monitoring of neck blood vessels","authors":"Meiyun Cao, Gennadi Saiko, T. Burton, A. Douplik","doi":"10.1117/12.2680679","DOIUrl":"https://doi.org/10.1117/12.2680679","url":null,"abstract":"Cardiovascular disease (CVD) is a leading cause of death globally. Current CVD diagnostic tests fail to predict early cardiovascular events and assess the risk of developing early CVD. Researchers are actively looking for biomarkers for CVD prediction, such as blood pressure, arterial stiffness, and pulse wave velocity (PWV). Several population-based clinical studies suggest increased PWV is associated with increased CVD mortality. In this study, we propose using a high-speed camera to study PWV as a biomarker of CVD with remote photoplethysmography (rPPG). We selected a reference signal based on distinct features, including peak and modulation depth variations, and used correlation to find the relationship between the local signals and the reference signal. The results revealed areas on the neck that positively and negatively correlated with selected reference signals, possibly representing the distribution of the significant neck vessels: carotid artery and jugular vein, which implies the feasibility of the remote estimation of local PWV using a high-speed camera, thereby expanding the potential applications of rPPG used for PWV estimation and assisted the CVD diagnosis.","PeriodicalId":434863,"journal":{"name":"Optical Engineering + Applications","volume":"167 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132460046","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigating timing jitter on a free-space high-bandwidth data communication link with seasonal weather variations 研究随季节天气变化的自由空间高带宽数据通信链路的时序抖动

Optical Engineering + Applications Pub Date : 2023-10-03 DOI: 10.1117/12.2678122

Vijit Bedi, V. Nikulin, Ka. Soderberg, L. Wessing, P. Ricci, Din Islam, William F. Lipe, Robert J. Dimeo, Christine A. Mathers, John W. Heinig

{"title":"Investigating timing jitter on a free-space high-bandwidth data communication link with seasonal weather variations","authors":"Vijit Bedi, V. Nikulin, Ka. Soderberg, L. Wessing, P. Ricci, Din Islam, William F. Lipe, Robert J. Dimeo, Christine A. Mathers, John W. Heinig","doi":"10.1117/12.2678122","DOIUrl":"https://doi.org/10.1117/12.2678122","url":null,"abstract":"Free-space optical communication (FSOC) holds unmatched potential for high bandwidth and secure communications while minimizing size, weight, and power (SWAP). However, the effects of atmospheric scintillations on high bandwidth signals limits data link performance by degrading OSNR (Optical signal-to-noise ratio) and Q-factor. A critical component due to which a communication signal quality deteriorates is timing jitter. Jitter may be due to timing of the data signal or it may be due to the amplitude variations in the data bit stream as it propagates through free-space. As the data bandwidth increases, these effects become more significant. A small-time deviation in a lower data rate signal which would be tolerable or be above a receiver sensitivity, turns into an intolerable signal at higher data rates as jitter increases. The total jitter (TJ) can be further broken down to deterministic jitter (DJ) and random jitter (RJ). These may help understand signal behavior and the root cause of degradation in a FSOC or any data communication link. Thus, for a system to achieve desired BER (bit-error-rate and bit-error-ratio), an in-depth analysis of jitter by investigating each of the subclass of both timing jitters, DJ and RJ, would be extremely helpful and enhance the robustness of the link. In this paper, we report in-depth jitter analysis from a FSOC data link at 10 Gbps propagating at 1550 nm.","PeriodicalId":434863,"journal":{"name":"Optical Engineering + Applications","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114879645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Minimized transient wavelength and power variations on the DFBLDs for 200Mbit/s DPS phase shift keying 最小的瞬态波长和功率变化的dfbld的200Mbit/s DPS相移键控

Optical Engineering + Applications Pub Date : 2023-10-03 DOI: 10.1117/12.2675471

You-Cheng Lin, Kuan Hu, Chih-Hsien Cheng, G. Lin

引用次数: 0

Undetected photon interference measurements on a silicon chip 在硅片上未被探测到的光子干涉测量

Optical Engineering + Applications Pub Date : 2023-10-03 DOI: 10.1117/12.2676372

Chiara Michelini, S. Signorini, V. Pruneri, Lorenzo Pavesi

{"title":"Undetected photon interference measurements on a silicon chip","authors":"Chiara Michelini, S. Signorini, V. Pruneri, Lorenzo Pavesi","doi":"10.1117/12.2676372","DOIUrl":"https://doi.org/10.1117/12.2676372","url":null,"abstract":"Interference measurements with undetected photons employ entangled photon pairs in order to overcome classical limitations in measurement sensitivity. With the undetected photon technique, one photon (signal) interacts with an object, and the signature of the interaction is stored in its entangled counterpart (idler): the interacting photon remains undetected, while the detection is performed on the photon that did not interact with the object. While the signal photon can be chosen in any spectral region suitable for the interaction, the idler photon is generated in a spectral region where detectors are efficient, scalable, and cheap. To date, the configurations proposed are in bulk setups. In this work, we propose a novel configuration on an integrated device, with the advantages of the reduced dimension, the lower cost and the robustness to alignment. In our experiment, we pumped a silicon-on-silica integrated circuit with a classical beam at a wavelength of 1.568 μm. Via intermodal spontaneous four-wave mixing, we generated highly non-degenerate time-energy entangled signal and idler photons at 1.99 μm and 1.29 μm, respectively. As we have integrated two identical sources of entangled photons in series, the photon pairs generated in the two sources are indistinguishable, and controlling the phase of the pump beam and the phase of the signal photons after the first nonlinear source, we observed interference patterns with 24% maximum visibility in the idler photon counts. We successfully measured the dephasing induced on the signal photons by measuring only the idler ones.","PeriodicalId":434863,"journal":{"name":"Optical Engineering + Applications","volume":"122 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122333842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

CsPbBr3 perovskite single crystals for X- and γ-radiation detectors 用于X和γ辐射探测器的CsPbBr3钙钛矿单晶

Optical Engineering + Applications Pub Date : 2023-10-03 DOI: 10.1117/12.2676107

V. Skliarchuk, P. Fochuk, O. Kopach, A. Bolotnikov, R. James

引用次数: 0

Integrated photonics based on nonlinear optical scattering 基于非线性光散射的集成光子学

Optical Engineering + Applications Pub Date : 2023-10-03 DOI: 10.1117/12.2680372

A. C. Amaro de Faria Júnior

引用次数: 0

Machine learning for optical turbulence prediction in geographically similar regions 地理相似区域光学湍流预测的机器学习

Optical Engineering + Applications Pub Date : 2023-10-03 DOI: 10.1117/12.2681468

Bethany Campbell, K. McBryde, Erich Walter, Kyle R. Drexler

引用次数: 0