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Role of Retinal Nerve Fiber Layer Thickness and Optic Disk Measurement by OCT onEarly Diagnosis of Glaucoma 被引量:3
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作者 Zanmei Hua Qiuyun Fang +2 位作者 Xiangyin Sha Ruiming Yang Zuopeng Hong 《Eye Science》 CAS 2015年第1期7-12,共6页
Purpose:.Glaucoma is an eye disease that can lead to irreversible optic nerve damage and cause blindness. Optical coherence tomography.(OCT) allows an early diagnosis of glaucoma by the measurements of the retinal ner... Purpose:.Glaucoma is an eye disease that can lead to irreversible optic nerve damage and cause blindness. Optical coherence tomography.(OCT) allows an early diagnosis of glaucoma by the measurements of the retinal nerve fiber and optic disc parameters.A retrospective study was designed to analyze the effects of the measurement of the retinal nerve fiber layer(RNFL) thickness and the optic disc tomography by spectraldomain OCT on the early diagnosis of suspected glaucoma and primary open angle glaucoma(POAG).Methods:.This was a clinical case-control study. The RNFL thickness around the optic disc and optic disk tomographic parameters of the control(n=51, 98 eyes), suspected glaucoma(n=81,.146 eyes), and POAG groups(n=55, 106 eyes) were measured by OCT. The parameters included superior, inferior, nasal and temporal mean RNFL thickness,.disc area(DA), cup area(CA), rim area(RA), disc volume(DV),cup volume(CV), rim volume(RV), cup / disc area ratio(CA / DA), rim / disc area ratio(RA / DA), cup / disc volume ratio(CV / DV) and rim / disc volume ratio(RV / DV).Results: Superior, nasal, and mean RNFL parameters, DA,CA,RA, DV, CV, CA / DA, RA / DA, CV / DV and RV / DV significantly differed among three groups by single-factorial ANOVA. Inferior and temporal RNFL thickness significantly differed between the control and POAG groups. No significant difference was observed in RV among three groups. In the POAG group,.the maximum area under the ROC curve(AROC) of mean RNFL thickness was 0.845. The maximum AROC of optic disk parameters was RA / DA(0.998), followed by CA / DA(0.997). The AROC of CA, RA, CV, and DV were all > 0.900.Conclusion:.OCT may serve as a useful diagnostic modality in distinguishing suspected glaucoma from POAG. 展开更多
关键词 视神经损伤 厚度控制 早期诊断 青光眼 视网膜 纤维层 华侨城 视盘
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Detection of Influenza Viruses Attached to an Optical Disk
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作者 Takayuki Shima Makoto Fujimaki +4 位作者 Akihiro Yoshida Subash C. B. Gopinath Masashi Kuwahara Yoshimichi Ohki Koichi Awazu 《Journal of Biomaterials and Nanobiotechnology》 2013年第2期145-150,共6页
Detection of polystyrene beads with a diameter of 100 nm was conducted using an optical disk drive tester equipped with a laser of 405 nm wavelength and an objective lens with a numerical aperture of 0.65. The polysty... Detection of polystyrene beads with a diameter of 100 nm was conducted using an optical disk drive tester equipped with a laser of 405 nm wavelength and an objective lens with a numerical aperture of 0.65. The polystyrene beads were used to mimic the influenza virus. A grooved disk with a (ZnS)85(SiO2)15/SiO2 layered surface structure was used for the detection. The detection of influenza viruses (A/Udorn/307/1972) with Au nanoparticles was also demonstrated using the optical disk drive tester. In this case, a grooved disk with an indium tin oxide (ITO) film was used. The ITO film functioned both to tune the reflectance of the disk and as an electrically conductive layer for scanning electron microscopy. In both cases, the target substances were successfully recognized in a single scan with a high scanning speed of 4.9 m/s. The results indicate that this optical disk system can be used to detect 100 nm scale substances like influenza viruses, which are smaller than the diffraction limit of the system. 展开更多
关键词 INFLUENZA VIRUS POLYSTYRENE BEAD optical disk Laser Reflectance Sensor Safety and Security
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Magneto-optical Disk Material for Improving the Density of Information Storage
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作者 夏红霞 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2001年第2期54-57,共4页
This paper introduces the fundamental principle and features ofmagneto-optical storage technol- ogy, and discuses the trend and aseries of key techniques for increasing the data storage density ofmagneto-opti- cal dis... This paper introduces the fundamental principle and features ofmagneto-optical storage technol- ogy, and discuses the trend and aseries of key techniques for increasing the data storage density ofmagneto-opti- cal disk. The three ways including MO media, recordingmethod and readout method for increasing the disk ca- pacity havebeen discussed. Moreover, the importance with the exchange-coupledeffect between the magnetic layers and recording domain morphology isemphasized. 展开更多
关键词 magneto-optical disk information storage recording density
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Study on Stereometric Parameters of Optic Nerve Head of Normal, Big-cupped Disk and Glaucomatous Eyes Using Heidelberg Retina Tomograph
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作者 Xing liu, Yunlan Ling, Xiaoping Zheng, Jingjing HuangZhongshan Ophthalmic Center, Sun Yat-sen University of Medical Sciences, Guangzhou 510060, China 《眼科学报》 2000年第3期163-167,共5页
Purpose: To investigate the difference of stereometric parameters of optic nerve head between the normal subjects and patients with big-cupped disk and primary open angle glaucoma (POAG).Methods: Twenty-two cases (44 ... Purpose: To investigate the difference of stereometric parameters of optic nerve head between the normal subjects and patients with big-cupped disk and primary open angle glaucoma (POAG).Methods: Twenty-two cases (44 eyes) of normal subjects, 17 cases (34 eyes) of patients with big-cupped disk and 19 cases (37 eyes) of patients with POAG underwent Heidelberg Retina Tomograph (HRT) examination to get topography images and stereometric parameters of optic nerve head.Results: The stereometric parameters of optic nerve head of the normal, patients with big-cupped disk and POAG were 1) disk area (mm2): 1. 995± 0. 501, 2. 407±0. 661 and 2. 248±0.498; 2) cup area (mm2): 0.573±0.264, 1. 095±0. 673 and 1. 340±0. 516; 3) cup/disk ratio: 0. 25±0. 095, 0. 428±0. 176 and 0. 589±0.195; 4) rim area (mm2): 1.461±0.328, 1.312±0.418 and 0. 905± 0.409; 5)cup volume (mm3): 0. 108±0. 073, 0. 347±0. 346 and 0. 550 ±0. 394; 6) rim volume (mm3): 0. 421±0. 111, 0. 378±0. 225 and 0. 224±0. 189; 7) mean cup 展开更多
关键词 青光眼 视网膜图 视乳头杯 视神经乳头
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基于ReSE-AG-Net的青光眼视盘视杯分割方法
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作者 李豪杰 郭子洋 +2 位作者 刘伟志 罗益 曹秒 《长春理工大学学报(自然科学版)》 2024年第4期115-121,共7页
分割视盘视杯是诊断青光眼的主要依据,因此提出了一种基于改进U-Net网络的青光眼视盘视杯分割方法,称为ReSE-AG-Net。并将ReSE-AG-Net、U-Net、M-Net、CE-Net和CDED-Net分别在Drishti-GS1数据集和RIM-ONE-R3数据集上进行测试,对得到分... 分割视盘视杯是诊断青光眼的主要依据,因此提出了一种基于改进U-Net网络的青光眼视盘视杯分割方法,称为ReSE-AG-Net。并将ReSE-AG-Net、U-Net、M-Net、CE-Net和CDED-Net分别在Drishti-GS1数据集和RIM-ONE-R3数据集上进行测试,对得到分割后的视盘视杯的Dice系数和IoU进行对比。实验结果表明,在Drishti-GS1数据集上,分割视盘的Dice系数和IoU分别是0.989 1和0.959 0,分割视杯的Dice系数和IoU分别是0.931 0和0.871 0,在RIMONE-R3数据集上,分割视盘的Dice系数和IoU分别是0.978 9和0.958 7,分割视杯的Dice系数和IoU分别是0.863 7和0.760 1,对比U-Net模型和现有的分割模型均有一定的提升,证明了该方法的可行性。 展开更多
关键词 青光眼 视盘视杯分割 U-Net ReSE-AG-Net
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近视病人青光眼诊断的研究进展
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作者 卫水娟 杨继红 《安徽医药》 CAS 2024年第10期1912-1917,共6页
近视是青光眼发病的高危因素,且研究表明近视程度越高,患青光眼的可能性就越大。近视病人青光眼诊断是一个特殊问题,这可能因为早期青光眼与近视的表现相似,所以许多近视病人因青光眼而使视力受到损害,但未引起临床医生考虑青光眼的可... 近视是青光眼发病的高危因素,且研究表明近视程度越高,患青光眼的可能性就越大。近视病人青光眼诊断是一个特殊问题,这可能因为早期青光眼与近视的表现相似,所以许多近视病人因青光眼而使视力受到损害,但未引起临床医生考虑青光眼的可能性。近年来随着眼科影像技术的发展,尤其是光学相干断层扫描与共焦激光眼底扫描红外成像及无赤光眼底照相技术的结合、光学相干断层扫描离散傅里叶变换分析与视野的结合,光学相干断层扫描血流成像的快速革新,临床医生可以从多方面了解近视与青光眼的发生发展,为早期诊断近视眼青光眼,及时干预治疗,从而为提高近视病人的视觉生活质量提供坚实的基础。 展开更多
关键词 近视 青光眼 诊断 光学相干断层扫描 视盘
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基于CD/DVD光盘的光波衍射研究
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作者 侯其哲 谢植鑫 +4 位作者 叶志杰 陈鑫伟 巢家乐 曾逼立 邹少辉 《韶关学院学报》 2024年第3期40-46,共7页
白炽灯光入射在CD/DVD光盘会呈现随着角度轻微变化发生相应变化的彩色线.基于CD/DVD光盘的制造工艺,利用MATLAB软件对衍射规律进行理论分析,使用分光计实验观察白炽灯照射下CD/DVD光盘呈现出彩色线的衍射现象,验证不同入射角、衍射角、... 白炽灯光入射在CD/DVD光盘会呈现随着角度轻微变化发生相应变化的彩色线.基于CD/DVD光盘的制造工艺,利用MATLAB软件对衍射规律进行理论分析,使用分光计实验观察白炽灯照射下CD/DVD光盘呈现出彩色线的衍射现象,验证不同入射角、衍射角、水平偏转角与波长的关系,获得不同条件下的衍射图案.为光学和材料科学等多个学科领域以及数字储存技术的发展提供新的思路和方向. 展开更多
关键词 光盘 分光计 光栅常数 衍射图案
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关于光盘上出现彩色线的实验研究
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作者 潘国柱 赵宗耀 +1 位作者 赵子言 吴克跃 《皖西学院学报》 2024年第2期110-114,共5页
为了探究光盘(CD或DVD)的光栅衍射规律,以2023年全国大学生物理学术竞赛“色彩线”这一题为例,从理论与实验两方面研究光盘在有无刻录、不同的刻录方式、不同的光路入射角度等条件下衍射条纹颜色的变化情况,探究光盘上光栅衍射规律。结... 为了探究光盘(CD或DVD)的光栅衍射规律,以2023年全国大学生物理学术竞赛“色彩线”这一题为例,从理论与实验两方面研究光盘在有无刻录、不同的刻录方式、不同的光路入射角度等条件下衍射条纹颜色的变化情况,探究光盘上光栅衍射规律。结果表明:光盘上衍射条纹颜色与光盘结构、入射光角度和光盘倾角有关。该研究对新型光盘材料和技术的开发有着一定的理论和实践意义。 展开更多
关键词 光盘 彩色线 光栅衍射
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EFFECTS OF SPUTTERING CONDITIONS OF Tb Fe Co MAGNETO OPTICAL FILM ON KERRR OTATION
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作者 X.Y.Zhang , Z.N.Liu , J.Yi and Z.W.Chen Dept.of Materials Eng.,Southwest Jiaotong University,Chengdu 610031 ,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1999年第4期630-632,共3页
In the practical magneto opticaldisk productionline,alloysputteringtargetisalwaysusedtosputter recording film , whileinlaid targetisrarely used .In ourlaboratory,a seriesof al loy targets forsputtering magneto- opti... In the practical magneto opticaldisk productionline,alloysputteringtargetisalwaysusedtosputter recording film , whileinlaid targetisrarely used .In ourlaboratory,a seriesof al loy targets forsputtering magneto- optical recording film were prepared and theeffect ofcomposition andsputtering parameterson magneto opticalpropertiesarestudied . Thesputter ing rateof Al,Siand Tb Fe Co( Mo) undertheconditionsof differentsputtering powerandN2 Argasflux weredetermined and baseontheresults,a variablecomposition andthickness of SiNcan beobtained by meansof regulating sputtering power and gasflux, kindsof Mosputtering filmsareobtained under differentsputtering power and gasflux, and Kerrloop lineofthese magneto opticalfilmsare measuredto acquiretheir propertiessuch as Kerrrota tion,then ,theeffectofsputteringtechnology on Kerrrotationisdiscussed . 展开更多
关键词 MAGNETO optical disk FILM MAGNETO optical material
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Optical coherence tomography in optic disc drusen
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作者 J.Alexander Fraser Lulu L.C.D.Bursztyn 《Annals of Eye Science》 2020年第1期22-34,共13页
Optic disc drusen (ODD) are hyaline deposits in the optic nerve head, occurring in approximately 2% of the population. ODD may be superficial and visible, or buried and either invisible or seen only as elevation of th... Optic disc drusen (ODD) are hyaline deposits in the optic nerve head, occurring in approximately 2% of the population. ODD may be superficial and visible, or buried and either invisible or seen only as elevation of the optic disc, mimicking optic disc edema. Advanced optic nerve imaging, including optical coherence tomography (OCT) can be used to diagnose and characterize ODD with very high resolution. Enhanced depth imaging (EDI-OCT) in particular has emerged as the optimal modality to directly visualize ODD. This modality has led to a greater ability to differentiate ODD from optic disc edema and prevent misdiagnosis or invasive testing. We review the characteristic findings of ODD on OCT, their distinguishing features, and the use of OCT as a biomarker in the neuro-ophthalmic assessment of ODD. 展开更多
关键词 DRUSEN optic disk TOMOGRAPHY optical coherence
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Structure and Magneto-Optical Characteristic Study of Optical Multilayer Thin Films
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作者 YANGCheng-tao 《Journal of Electronic Science and Technology of China》 2005年第1期94-95,共2页
关键词 multiplayer soft x-ray REFLECTIVITY SUPERLATTICE magneto-optical disk
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糖尿病患者视盘周围血流和视网膜神经纤维层厚度变化及相关性分析 被引量:1
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作者 罗莎 王月 封利霞 《临床眼科杂志》 2023年第4期299-304,共6页
目的观察无糖尿病视网膜病变的2型糖尿病患者(NDR)及增生型糖尿病视网膜病变(PDR)治疗后的视盘周围血流密度和神经纤维层(pRNFL)厚度变化并进行相关性分析。方法回顾性病例对照研究。选取确诊为PDR(IV或V期)并治疗后稳定3个月的患者25例... 目的观察无糖尿病视网膜病变的2型糖尿病患者(NDR)及增生型糖尿病视网膜病变(PDR)治疗后的视盘周围血流密度和神经纤维层(pRNFL)厚度变化并进行相关性分析。方法回顾性病例对照研究。选取确诊为PDR(IV或V期)并治疗后稳定3个月的患者25例(25只眼)、NDR患者38例(38只眼),同期纳入年龄匹配的健康成年人24例(24只眼)作为对照组。受检者均行相干光层析血管成像术(OCTA)检查,将视盘周围分为颞侧上方(TU)、上方颞侧(ST)、上方鼻侧(SN)、鼻侧上方(NU)、鼻侧下方(NL)、下方鼻侧(IN)、下方颞侧(IT)、颞侧下方(TL)8个象限,观察三组在不同区域视盘旁放射状毛细血管网(RPC)血流密度和pRNFL厚度的差异,运用Spearman相关分析两者之间的相关性。结果与正常对照组比较,NDR组盘周整体、上半侧、下半侧以及TU象限RPC血流密度降低(P<0.05),而PDR组在各区域的RPC血流密度均进一步减少(P<0.05)。NDR组与对照组在各区域pRNFL厚度差异均无统计学意义(P>0.05),PDR组IN、IT和ST象限pRNFL厚度均小于对照组且IT和ST象限pRNFL厚度小于NDR组(P<0.05)。PDR组SN和IN象限pRNFL厚度和RPC血流密度呈高度正相关(r=0.743、0.719,P<0.001),NDR组鼻侧象限(NU和NL)pRNFL厚度和RPC血流密度呈中度正相关(r=0.658、0.672,P<0.001)。结论OCTA在糖尿病视神经微循环形态评价中具有重要价值。糖尿病患者未发生DR时视盘周围微循环改变可能早于神经纤维的损害,以颞侧上方最为显著。当病情发展至PDR时,pRNFL明显变薄且视盘旁RPC血流密度进一步减少,两者密切相关。 展开更多
关键词 糖尿病视网膜病变 相干光层析成像术 视盘 局部血流 视网膜神经纤维层厚度
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基于支持向量机的眼底图像视盘定位算法 被引量:1
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作者 吴晔 李成辉 姚骏 《工业控制计算机》 2023年第2期98-99,101,共3页
视盘定位是计算机辅助诊断中处理眼底图像的重要步骤。为了准确、稳健地确定视盘的位置,提出了一种基于支持向量机(SVM)的视盘定位算法。根据眼底图像中亮区域的结构和强度特征,训练支持向量机分类器识别亮区域。在这些候选区域的基础... 视盘定位是计算机辅助诊断中处理眼底图像的重要步骤。为了准确、稳健地确定视盘的位置,提出了一种基于支持向量机(SVM)的视盘定位算法。根据眼底图像中亮区域的结构和强度特征,训练支持向量机分类器识别亮区域。在这些候选区域的基础上创建一个凸包来定位视盘的中心。与文献中的视盘定位方法相比,由于机器学习算法的应用提高了亮区域的分类精度,该方法能够以更高的精度定位视盘中心。测试了三个共259张图像的公共数据集,以评估性能。该方法对DRIVE数据集、DIARETDB0数据集和DIARETDB1数据集的准确率分别为100%、96.9%、97.8%。 展开更多
关键词 视盘定位 支持向量机 亮区域 凸包
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眼胶质淋巴系统及相关眼病研究进展
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作者 祝光宇 程雨欣 路雪婧 《中国全科医学》 CAS 北大核心 2023年第26期3330-3334,共5页
最近发现的眼胶质淋巴系统更新了临床对眼内循环的认知,其是一个由神经胶质细胞终足上水通道蛋白4(AQP4)驱动并依赖视网膜动、静脉周围间隙的房水-组织液交换系统,最终起到将β淀粉样蛋白等神经毒性物质排出眼外的作用。本文综述了眼胶... 最近发现的眼胶质淋巴系统更新了临床对眼内循环的认知,其是一个由神经胶质细胞终足上水通道蛋白4(AQP4)驱动并依赖视网膜动、静脉周围间隙的房水-组织液交换系统,最终起到将β淀粉样蛋白等神经毒性物质排出眼外的作用。本文综述了眼胶质淋巴系统的组成和功能,描述了生理状态下该系统具体的循环路径及其在青光眼、视盘水肿、Terson综合征(TS)等疾病过程中的障碍机制,并提出未来可确定眼胶质淋巴系统具体调控环节,针对具体环节改善该系统的功能,如利用中药多靶点、多途径的优势促进眼内代谢废物的清除,这将有机会为青光眼等诸多眼病和一些中枢神经系统疾病的治疗带来希望。 展开更多
关键词 神经胶细胞类淋巴系统 眼胶质淋巴系统 青光眼 视盘水肿 TERSON综合征 综述
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Aggregation-induced emission (AIE) luminescent materials boosting optical storage into the new era of petabit-level capacity
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作者 Siwei Zhang Pengfei Zhang Ben Zhong Tang 《Aggregate》 EI CAS 2024年第3期1-3,共3页
The recording of information stands as the most significant milestone in human civilization.Historically,the recording and storage of information have undergone a technological evolution from paintings to carvings,scri... The recording of information stands as the most significant milestone in human civilization.Historically,the recording and storage of information have undergone a technological evolution from paintings to carvings,scribing,and digitization.The invention of optical compact discs(CDs)was one of the major landmarks in digital information technology.Over the past half-century,scientists have endeavored to enhance optical storage capacity by improving both optical systems and optical storage materials,as shown in Scheme 1.In terms of commercial products,the storage capacity has increased from 700 MB(CDs)to 27 GB(Blu-ray discs)by optimizing the optical system based on the same optical storage medium(polycarbonate).To surpass the conventional optical diffraction limit,the optical systems have evolved from traditional lasers to nonlinear two-photon absorption(TPA)and stimulated emission depletion(STED),which has minified the laser spot size from microns to approximately tens of nanometers,marking a remarkable achievement. 展开更多
关键词 aggregation-induced EMISSION optical STORAGE super disk
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Rastall gravity:accretion disk image in the context of radiation fields and visual transformations compared to Reissner-Nordström black hole
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作者 黄宇翔 郭森 +3 位作者 梁宇 崔宇昊 蒋青权 林恺 《Chinese Physics C》 SCIE CAS CSCD 2024年第4期174-182,共9页
In this study,we investigated the astronomical implications of Rastall gravity,particularly its behavior amidst a radiation field compared to Reissner-Nordström(RN)black holes.We found a crucial correlation betwe... In this study,we investigated the astronomical implications of Rastall gravity,particularly its behavior amidst a radiation field compared to Reissner-Nordström(RN)black holes.We found a crucial correlation between the dynamics of the accretion disk and the parameters Q and Nr,which properly reflect the influence of spacetime metrics on the disk’s appearance.Elevated electric charge Q causes contraction in the disk’s orbit due to enhanced gravitational effects,while higher Nr values lead to outward expansion,influenced by the attributes of the radiation field.Interestingly,the charged black holes surrounded by radiation fields exhibit distinct visual disparities from RN black holes.Brightness decreases and expansion occurs within the innermost stable circular orbit of the accretion disk with rising Nr values.Our study also reveals the process by which the accretion disk transitions from a conventional disk-like structure to a hat-like form at different observation angles,with the redshift effect gradually intensifying.Moreover,the results of the considered Rastall gravity radiation field are consistent with the constraints of the gravitational lensing of the host galaxy on Rastall gravity parameters,thereby enhancing the consistency between theoretical predictions and actual observations. 展开更多
关键词 Rastall theory optical appearance thin accretion disk
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Large aperture disk standing-wave unstable resonator with intra-cavity adaptive correction
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作者 于益 易家玉 +7 位作者 徐浏 尚建力 吴晶 童立新 高清松 唐淳 张卫 陈磊 《Chinese Optics Letters》 SCIE EI CAS CSCD 2024年第5期57-61,共5页
An unstable resonator with seven large aperture ceramic disks and intra-cavity adaptive correction is presented.The composite ceramic disks with absorption rings were adopted to suppress amplified spontaneous emission... An unstable resonator with seven large aperture ceramic disks and intra-cavity adaptive correction is presented.The composite ceramic disks with absorption rings were adopted to suppress amplified spontaneous emission.An intra-cavity aberration non-conjugate correction based on round-trip wavefront and relaxation iteration was applied in the resonator.After tilt and defocus were corrected in turn,an average output power of 4.5 kW was obtained.The corresponding beam quality factorβwas 19.5.After tilt,defocus,and high order aberrations were corrected,the average output power was increased to 5.4 kW,and the beam quality factorβwas improved to 6.8. 展开更多
关键词 Nd:YAG disk unstable resonator intra-cavity adaptive optics composite ceramic
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高速公路通信光缆单盘测试的重要性分析
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作者 周智龙 《现代传输》 2023年第4期67-70,共4页
光缆线路工程是光纤通信的基础设施,其工程施工质量的好坏将直接影响光纤通信系统的性能。施工敷设前对进场的光缆原材料及连接器等附件进行检验是保证施工质量的前提。单盘光缆运输到施工现场在穿缆敷设之前,应进行必要的光缆单盘测试... 光缆线路工程是光纤通信的基础设施,其工程施工质量的好坏将直接影响光纤通信系统的性能。施工敷设前对进场的光缆原材料及连接器等附件进行检验是保证施工质量的前提。单盘光缆运输到施工现场在穿缆敷设之前,应进行必要的光缆单盘测试。光缆单盘测试内容包括对运输到施工点的整盘光缆及连接器件的规格型式和数量进行核对检查,对外观质量进行检查,对光纤特性质量进行测量检查。通过以上检测可以确认光缆及其连接器材的规格、光缆的质量是否满足设计文件或合同的有关规定要求。光缆质量的检查主要是对光纤衰减系数的测量、光缆长度的复测及对光纤背向散射曲线(OTDR曲线)的观察,通过上述几个指标的测试,可以准确的判断运输到施工现场的光缆是否满足设计文件的要求,对后续的施工进度及施工质量起到积极的作用。 展开更多
关键词 光缆线路 光缆敷设 单盘测试 OTDR 光纤衰减
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聚碳酸酯光学性能应用及改进研究进展 被引量:24
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作者 李复生 魏东炜 +2 位作者 崔金华 殷金柱 宋光复 《塑料》 CAS CSCD 2003年第3期65-69,共5页
概述了光学级聚碳酸酯结构与光学性能的关系和其在光学领域的应用,对其光学异向性产生的原因进行了讨论,并对改善聚碳酸酯光学异向性的途径进行了归纳,通过采用共聚、共混方法可使聚碳酸酯的双折射得到有效的降低。
关键词 聚碳酸酯 光学性能 应用 改进 研究进展 光盘盘基 双折射 共聚
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超高度近视超声乳化白内障吸出术后黄斑区光学相干断层扫描改变 被引量:14
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作者 许莉 刘建巨 +4 位作者 张红 谢芳 宋甄 施展 刘平 《国际眼科杂志》 CAS 2009年第1期52-54,共3页
目的:观察超高度近视患者超声乳化白内障吸出术后黄斑区光学相干断层扫描(optical coherence tomography,OCT)的改变。方法:眼轴≥27mm,屈光度>-10.00D的超高度近视患者27例和单纯老年性白内障患者30例,白内障超声乳化吸出术前及术后... 目的:观察超高度近视患者超声乳化白内障吸出术后黄斑区光学相干断层扫描(optical coherence tomography,OCT)的改变。方法:眼轴≥27mm,屈光度>-10.00D的超高度近视患者27例和单纯老年性白内障患者30例,白内障超声乳化吸出术前及术后1,3mo的黄斑区OCT检查,对比观察手术眼黄斑区OCT图象的变化。结果:超高度近视患者术前及术后1mo黄斑区中心凹神经纤维层的厚度分别是:133±24μm和173±32μm两者比较,差异有统计学意义(t=2.648,P<0.01),术后3mo黄斑区中心凹神经纤维层的厚度138±30μm,与术后1mo的神经纤维层的厚度相比,差异有统计学意义(t=2.794,P<0.01),与术前的神经纤维层的厚度相比,差异无统计学意义(t=1.246)。视网膜厚度的增加与术后视力呈负相关(r=-0.56)。术后OCT检查还发现,黄斑区的全层裂孔1例,视网膜牵拉1例,黄斑区出血1例,黄斑区神经纤维层撕裂1例。单纯老年性白内障超声乳化吸出术前及术后1mo的神经纤维层厚度分别是:147±5μm和149±5μm,两者比较,差异无统计学意义(t=1.0416),术后3mo黄斑区中心凹神经纤维层的厚度150±5μm,与术前及术后1mo的视网膜厚度相比,差异无统计学意义(t=1.034和t=1.316)。结论:超高度近视患者术后1mo大部分发生黄斑区水肿,视网膜厚度明显增加,且视网膜厚度的增加与视力呈负相关。部分患者出现黄斑区的全层裂孔,视网膜牵拉,黄斑区出血,黄斑区神经纤维层撕裂。3mo左右,大部分患者黄斑区水肿消退,并与术前相比无明显差异。 展开更多
关键词 超高度近视 超声乳化吸出 黄斑区 光学相干断 层扫描
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