Evaluation of visual quality of spherical and aspherical intraocular lenses by Optical Quality Analysis System

AIM： To evaluate the impact of spherical and aspherical intraocular lenses on the postoperative visual quality of age-related cataract patients using Optical Quality Analysis System （OQAS）. METHODS： Seventy-four eyes with age-related cataracts were randomly divided into spherical and aspherical lens implantation groups. Best-corrected visual acuity （BCVA） was measured preoperatively, one day, one week, two weeks, one month and two months after surgery. A biometric systems analysis using the OQAS objective scattering index （OSI） was performed. RESULTS： There were no significant differences in visual acuity （P〉0.05） before and after spherical and aspheric lens implantation. There was a negative linear correction between the OSI value and BCVA （t-=-0.634, P=-0.000）, and positive corrections between the OSI value and the lens LOCUS III value of nucleus color （NC）, nucleus opacity （NO）, cortex （C） and posterior lens capsular （P） （r=0.704, P=0.000; r=0.514, P=0.000; r=0.276, P=0.020; r=0.417, P=-0.000, respectively）. OSI values of spherical vs aspherical lenses were 11.5±3.6 vs 11.8±3.4, 4.1±0.9 vs 3.3±0.8, 3.5±0.9 vs 2.7±0.7, 3.3±0.8 vs 2.6±0.7, 3.2±0.7 vs 2.5±0.8, and 3.2±0.8 vs 2.50.8 before and ld, 1, 2wk, 1 and 2mo after surgery, respectively. All time points varied significantly （P〈0.01） between the two groups. CONCLUSION： Aspherical IOLs does not significantly affect visual acuity compared with spherical IOLs. The OSI value, was significantly lower in the aspherical lens group compared with the spherical lens. This study shows that objective visual quality of aspheric IOLs is better than that of the spherical lens by means of OQAS biological measurement method.

AFM Analysis on Polymer Optical Micro-Resonators: Investigation on Quality Factor Origin

This paper deals with the surface analysis of spherical polymeric optical micro-resonators in order to correlate surface defects with optical characteristics. Atomic force microscopy was used on structures to determine surface quality, which is the main origin of optical scattering losses. Surface morphologies were numerically treated to enable a relevant investigation on surface parameters such as root mean square (RMS) roughness (30.1 +/- 3.0 nm) or correlation length (few microns) necessary to express optical quality factors. A statistical analysis was conducted for calibration of these parameters as a function of cavities’ diameter. Results are in perfect agreement with spectral analyses performed in parallel on others structures. This comparison highlights the main role of scattering losses on quality factor origin.

Optical quality of toric intraocular lens implantation in cataract surgery

AIM: To analyze the optical quality after implantation of toric intraocular lens with optical quality analysis system.METHODS: Fifty-two eyes of forty-four patients with regular corneal astigmatism of at least 1.00 D underwent implantation of Acry Sof toric intraocular lens, including T3 group 19 eyes, T4 group 18 eyes, T5 group 10 eyes,T6 group 5 eyes. Main outcomes evaluated at 3mo of follow-up, included uncorrected distance visual acuity(UDVA), corrected distance visual acuity(CDVA), residual refractive cylinder and intraocular lens(IOL) axis rotation.Objective optical quality were measured using optical quality analysis system(OQAS Ⅱ, Visiometrics, Spain),included the cutoff frequency of modulation transfer function(MTFcutoff), objective scattering index(OSI),Strehl ratio, optical quality analysis system value(OV)100%, OV 20% and OV 9% [the optical quality analysis system(OQAS) values at contrasts of 100%, 20%, and 9%].RESULTS: At 3mo postoperative, the mean UDVA and CDVA was 0.18 ±0.11 and 0.07 ±0.08 log MAR; the mean residual refractive cylinder was 0.50 ±0.29 D; the mean toric IOL axis rotation was 3.62 ±1.76 degrees, the mean MTFcutoff, OSI, Strehl ratio, OV 100%, OV 20% and OV9% were 22.862 ±5.584, 1.80 ±0.84, 0.155 ±0.038, 0.76 ±0.18,0.77±0.19 and 0.78±0.21. The values of UDVA, CDVA, IOL axis rotation, MTFcutoff, OSI, Strehl ratio, OV100%,OV20% and OV9% depending on the power of the cylinder of the implantation were not significantly different(P 】0.05), except the residual refractive cylinder(P 【0.05).CONCLUSION: The optical quality analysis system was useful for characterizing the optical quality of Acry Sof toric IOL implantation. Implantation of an Acry Sof toric IOL is an effective and safe method to correct corneal astigmatism during cataract surgery.

Multi-Modality Medical Image Fusion Based on Wavelet Analysis and Quality Evaluation

Multi-modality medical image fusion has more and more important applications in medical image analysis and understanding. In this paper, we develop and apply a multi-resolution method based on wavelet pyramid to fuse medical images from different modalities such as PET-MRI and CT-MRI. In particular, we evaluate the different fusion results when applying different selection rules and obtain optimum combination of fusion parameters.

Effect of low-degree astigmatism on the objective visual quality

AIM:To evaluate the effect of low-degree astigmatism on objective visual quality through the Optical Quality Analysis System(OQAS).METHODS:This study enrolled 46 participants(aged 23 to 30y,90 eyes)with normal or corrected-to-normal vision.The cylindrical lenses(0,0.5,0.75,1.0,and 1.25 D)were placed at the axial direction(180°,45°,90°,and 135°)in front of the eyes with the best correction to form 16 types of regular low-degree astigmatism.OQAS was used to detect the objective visual quality,recorded as the objective scattering index(OSI),OQAS values at contrasts of 100%,20%,and 9%predictive visual acuity(OV100%,OV20%,and OV9%),modulation transfer function cut-off(MTFcut-off)and Strehl ratio(SR).The mixed effect linear model was used to compare objective visual quality differences between groups and examine associations between astigmatic magnitude and objective visual quality parameters.RESULTS:Apparent negative relationships between the magnitude of low astigmatism and objective visual quality were observed.The increase of OSI per degree of astigmatism at 180°,45°,90°,and 135°axis were 0.38(95%CI:0.35,0.42),0.50(95%CI:0.46,0.53),0.49(95%CI:0.45,0.54)and 0.37(95%CI:0.34,0.41),respectively.The decrease of MTFcut-off per degree of astigmatism at 180°,45°,90°,and 135°axis were-10.30(95%CI:-11.43,-9.16),-12.73(95%CI:-13.62,-11.86),-12.75(95%CI:-13.79,-11.70),and-9.97(95%CI:-10.92,-9.03),respectively.At the same astigmatism degree,OSI at 45°and 90°axis were higher than that at 0°and 135°axis,while MTFcut-off were lower.CONCLUSION:Low astigmatism of only 0.50 D can significantly reduce the objective visual quality.

RESEARCH ON WATER QUALITY TESTS BASED ON OPTICAL WAVEGUIDE SURFACE PLASMON RESONANCE TECHNOLOGY

The water quality testing principle by surface plasmon resonance(SPR)is introduced.Using the scanning mode angular spectral testing and the CCD angular spectral testing,a kind of highresolution,wide-range,and portable optical waveguide SPR angular spectral testing system is studied,the method of improving the testing accuracy is discussed,and a long-life surface plasmon optical waveguide transducer is also proposed.Utilizing the SPR testing system,we contrastively tack some test for several sorts of solution,the results presented that significant differences of SPR peaks observed in different sorts of liquid,which indicated the effectiveness of SPR technology used in water quality testing and analysis.

光电容积脉搏波技术在可穿戴医疗设备中的应用及其未来发展

光电容积脉搏波(Photoplethysmography,PPG)技术,作为一种非侵入式的生理参数监测方法,在心率、血氧饱和度以及其他生理指标的实时监测中已广泛应用。随着可穿戴技术的快速发展,PPG技术在医疗设备领域呈现出广阔的应用前景。本文详细讨论了PPG技术的基本原理、在可穿戴医疗设备中的应用现状及面临的挑战,同时探索了技术的未来发展方向。

基于超声-微纳米气泡辅助技术的可变光程水质多参数检测方法研究

针对目前国家标准分析检测水质多参数方法存在的科学与技术问题,提出了一种基于超声-微纳米气泡(US-MNB)辅助技术、连续光谱法和顺序注射分析法(SIA)的可变光程水质多参数检测新方法。设计水质多参数检测系统,通过检测总磷(TP)、化学需氧量(COD)、氨氮(NH_(3)-N)和六价铬(Cr^(6+))四种水质参数,验证了新方法的可行性。系统设计的核心是基于超声与微纳米气泡相结合的消解室以及具有可变光程功能的光谱扫描检测室,可达到快速消解和稳定检测的目的。同时系统基于国家水质检测标准,优化了水质多参数联合检测流程,并利用分光光度法和顺序注射分析技术对四种水质参数的含量进行连续光谱检测。首先,在常温常压下采用US-MNB辅助技术结合强氧化剂对TP进行消解,同时对检测室中NH_(3)-N参数显色反应后的化合物直接进行光谱扫描测定,消解后,再进行TP的测定。同理,消解COD的同时,对检测室中的Cr^(6+)参数显色反应后的化合物直接进行光谱扫描测定,消解后,再进行COD的测定。整个检测过程所用时间大幅降低,可在短时间内自动完成水质多参数的测定,显著地提高了检测的效率。以上述四种水质参数为测定对象,利用最小二乘法构建回归模型,拟合回归方程并计算相关系数,并绘制各参数的浓度-吸光度标准工作曲线。结果表明:TP标准工作曲线拟合系数≥0.9845,且浓度与吸光度成正相关,重复性(RSD)为3.05%~3.62%,加标回收率为97.8%~103.6%;COD标准工作曲线拟合系数≥0.9987,且浓度与吸光度成负相关,重复性(RSD)为2.12%~2.74%,加标回收率为98.7%~104.7%;NH_(3)-N标准工作曲线拟合系数≥0.9953,且浓度与吸光度成正相关,重复性(RSD)为3.41%~3.59%,加标回收率为99.2%~102.4%;Cr^(6+)标准工作曲线拟合系数≥0.9938,且浓度与吸光度成正相关,重复性(RSD)为3.51%~3.92%,加标回收率为98.9%~109.3%。系统可准确测定水样中TP、COD、NH_(3)-N和Cr^(6+)的含量,且具有良好的稳定性与可靠性。基于超声-微纳米气泡辅助技术的可变光程水质多参数检测方法研究,对于拓宽光谱法在水质多参数快速检测领域的应用以及提升检测效率等方面的研究具有重要作用。

大功率LED灯的光学仿真设计

大功率LED灯具作为一种新型的照明产品,光学仿真设计是LED灯具设计过程中关键的环节之一,它能够模拟LED灯具的光学性能、发光特性、照度分布等重要参数,为灯具的优化设计和生产提供后期的指导和检验,有助于提高LED灯具的性能和质量,并促进其市场竞争力的提升。因此,研究目的在于探究大功率LED灯的光学仿真设计,为其质量提升、技术提升和应用推广提供重要支持。首先对大功率LED灯的光学特性进行了理论分析和计算,结合实际生产和应用需求,建立了一套基于光学仿真软件的LED灯光学仿真设计方案。

矿用无源灰分仪在同忻煤矿井下的应用实践

针对同忻煤矿在线监测井下毛煤灰分的应用需求,基于灰分与煤的天然放射性呈正相关的原理,通过采用高射线透过率材料的隔爆型矿用射线探测器、由隔离变压器供电的光纤通讯分析仪表以及由内外屏蔽实现低本底水平的环境屏蔽体,完成了井下矿用无源灰分仪的设计,并将之应用于同忻煤矿井下毛煤的灰分监测。实践表明:矿用无源灰分仪应用效果良好,测量值与人工化验值的均方根误差低于1.26%;利用灰分监测数据指导井下采煤生产,使毛煤年平均灰分下降了0.76个百分点,达到了从源头加强煤质管控的目的。

Atmospheric aerosol pollution across China:a spatiotemporal analysis of satellite-based aerosol optical depth during 2000–2016

Increasing attention has been paid to the deterioration of air quality in China during the past decade.This study presents the spatiotemporal variations of aerosol concentration across China during 2000–2016 using aerosol optical depth(AOD)from the atmospheric product of Moderate Resolution Imaging Spectroradiometer.Percentile thresholds are applied to define AOD days with different loadings.Temporally,aerosol concentration has increased since 2000 and reached the highest level in 2011;then it has declined from 2011 to 2016.Seasonally,aerosol concentration is the highest in summer and the lowest in winter.Spatially,North China and Sichuan Basin are featured by high aerosol concentration with increasing trends in North China and decreasing trends in Sichuan Basin.North,Southeast and Southwest China have been through increasing days with low AOD loading;however,Northeast China has experienced increasing days with high AOD loading.It is likely that air quality influenced by aerosols has notably improved over North China in spring and summer,over Southwest and Southeast China in autumn,but has degraded over Northeast China in autumn.

SMILE与EVO-ICL植入术矫正中度近视的短期视觉质量观察

目的:探讨飞秒激光小切口角膜基质透镜取出术(SMILE)与中央孔型有晶状体眼后房型人工晶状体(EVO-ICL)植入术矫正中度近视术后短期视觉质量表现。方法:前瞻性对照研究。选取2021-04/2022-02在潍坊眼科医院行SMILE和EVO-ICL植入术的中度近视患者51例51眼,根据手术方式分为SMILE组(30例30眼)和EVO-ICL组(21例21眼)。分别于术前、术后1wk,1、3mo观察两组患者视力[裸眼远视力(UDVA)、矫正远视力(CDVA)]、屈光度[等效球镜度(SE)]及双通道客观视觉质量分析系统(OQASⅡ)相关参数的变化,并填写视觉质量(QoV)调查问卷。结果:术后3mo,SMILE组和EVO-ICL组安全性指数(术后CDVA/术前CDVA)分别为1.20(1.00,1.20)和1.20(1.00,1.38),有效性指数(术后UDVA/术前CDVA)分别为1.00(1.00,1.20)和1.00(1.00,1.20);SE在±0.50D以内的比例分别为87%和100%。SMILE组术后客观散射指数(OSI)值增加,术后1wk,1mo调制传递函数截止频率(MTF cutoff)、对比度视力(VA)100%、VA20%及术后各时间点斯特列尔比(SR)、VA9%均较术前降低(均P<0.05);EVO-ICL组术后各时间点OSI、MTF cutoff、SR、VA与术前相比均无差异(均P>0.05)。SMILE和EVO-ICL植入术后最常见的视觉症状分别为视觉朦胧和光晕。结论:SMILE和EVO-ICL植入术矫正中度近视术后短期均有良好的安全性、有效性及可预测性,两种手术术后均有视觉症状的发生,但患者总体满意度高,且EVO-ICL植入术后具有更好的客观视觉质量表现。

光程差分析系统和三维眼前节分析诊断系统综合分析屈光性白内障手术术后视觉质量的风险因素

目的:探讨光程差分析系统(OPD-ScanⅢ)和三维眼前节分析诊断系统(Pentacam)综合分析屈光性白内障手术术后视觉质量的风险因素。方法:纳入中山爱尔眼科医院2020年4月至2022年4月200例白内障患者进行前瞻性研究。所有患者均接受屈光性白内障手术治疗,于术前、术后1个月、术后3个月,测量所有患者视力恢复情况;通过OPD-ScanⅢ检查测量所有患者全眼总高阶像差;通过Pentacam检查患者角膜曲率、全角膜高阶像差。于术后3个月,采用视功能与生存质量调查问卷(NEI-VFQ-25)评估患者视觉质量。结果:术后1个月、术后3个月时患者裸眼视力、矫正视力均较术前提高,且术后3个月高于术后1个月,差异有统计学意义(P<0.05);经过屈光性白内障手术,患者总高阶像差、全角膜高阶像差较术前升高,Km较术前下降,差异有统计学意义(P<0.05);经多元线性回归分析,结果显示,总高阶像差高、全角膜高阶像差高是影响屈光性白内障手术术后视觉质量的风险因素。结论:总高阶像差高、全角膜高阶像差高是影响屈光性白内障手术术后视觉质量的风险因素,可于术前通过OPD-ScanⅢ和Pentacam精确评估患者高阶像差,减少高阶像差升高幅度,提高术后视觉质量。

T-PRK与SMILE矫正低度近视的视觉质量观察

目的:观察经上皮准分子激光角膜切削术(T-PRK)与飞秒激光小切口角膜基质透镜取出术(SMILE)矫正低度近视的角膜像差变化及视觉质量特点。方法:前瞻性队列研究。选取2021-04/2022-04于潍坊眼科医院行T-PRK手术32例32眼及SMILE手术45例45眼的低度近视患者,比较两组术后裸眼视力(UCVA)、最佳矫正视力(BCVA)、等效球镜(SE)、角膜高阶像差(HOAs)及客观视觉质量。结果:所有患者均顺利完成手术,未见感染等并发症。术后3mo,T-PRK组与SMILE组的安全指数分别为1.13±0.16和1.16±0.17(P=0.48),有效指数分别为1.10±0.20和1.15±0.18(P=0.27)。T-PRK组和SMILE组UCVA(LogMAR)≤0的占比分别为94%和98%。两组残余SE在±0.50D内的占比分别为88%和87%。两组患者HOAs和球差均显著升高(P≤0.01),且两组间增加量无差异(P=0.31、0.89)。两组患者水平彗差、水平三叶草、垂直三叶草均无显著性变化(P>0.05)。SMILE组垂直彗差显著升高(P<0.001),而T-PRK组无显著性变化(P>0.05),且SMILE组的增加量明显大于T-PRK组(P<0.001)。两组间OSI、MTF_(cut off)、SR、VA100%、VA20%、VA9%比较均未见差异(P>0.05)。结论:T-PRK与SMILE矫正低度近视均有良好的安全性、有效性和视觉质量,SMILE手术与T-PRK手术相比诱导更多的垂直彗差。

区域折射型与衍射折射型多焦点人工晶状体植入术后患者视力与视觉质量对比研究

目的对比分析白内障患者植入区域折射型多焦点人工晶状体(SBL-3)与衍射折射型多焦点人工晶状体(Zeiss809)后的视力和视觉质量。方法选取2016年5月至2017年6月在我院就诊的白内障患者80例100眼,其中39例50眼植入SBL-3(SBL组),41例50眼植入Zeiss809(Zeiss组)。术前两组患者性别、年龄、眼轴长度和角膜曲率等差异均无统计学意义(均为P>0.05)。术后3个月观察指标包括患者裸眼远、中、近视力,绘制术眼离焦曲线,检测患者客观视觉质量的客观散射指数(OSI)、调制传递函数截止频率(MTFcutoff)、斯特列尔比(SR),进行主观视觉质量问卷调查。结果术后两组患者术眼情况稳定,无高眼压及并发症出现。SBL组和Zeiss组患者术后3个月的裸眼远视力均较术前明显提高,差异均有统计学意义(均为P<0.01)。术后两组患者间裸眼近视力、远视力差异均无统计学意义(均为P>0.05);SBL组患者较Zeiss组裸眼中视力更好,差异有统计学意义(P=0.04)。离焦曲线图显示SBL组在-1.50 D(70 cm)处裸眼中视力较Zeiss组好。两组患者术后OSI、MTFcutoff和SR均较术前明显改善,差异均有统计学意义(均为P<0.05)。术后3个月SBL组与Zeiss组OSI、MTFcutoff和SR差异均无统计学意义(均为P>0.05)。术后3个月SBL组和Zeiss组分别有3眼及4眼发生夜间光晕,两组间发生率差异无统计学意义(P>0.05)。结论区域折射型多焦点人工晶状体和衍射折射型多焦点人工晶状体植入均能给白内障患者术后提供较为满意的视力。两种人工晶状体植入后患者视觉质量均明显改善。

光纤反射型传感器用于水中铅的测定

研究了一种将二甲酚橙固定在上海717阴离子交换树脂上作为试剂相的光导纤维反射型传感器。铅离子与固定在阴离子交换树脂上的二甲酚橙的络合反应,使试剂相光反射强度发生了很大的变化,从而使溶液中的铅离子得以测定。传感器具有较高的灵敏度和良好的选择性,已成功用于水中铅的检测。

BaTiO_3晶体薄膜PLD法生长工艺参量研究

采用脉冲激光沉积方法在单晶MgO基片上外延生长了BaTiO3晶体薄膜.为改善薄膜的结晶质量和表面粗糙度,研究并优化了生长工艺中生长温度和激光能量两个参量,并对薄膜样片实行原位退火.找到了BaTiO3薄膜在优先方向上的结晶效果,分析了结晶质量对生长温度的依赖关系和不同激光能量对结晶薄膜的表面粗糙度的影响.利用X射线衍射仪测定结晶效果与特性,原子力显微镜表征BaTiO3薄膜的结晶表面形貌与粗糙度.测试结果表明,在c轴取向生长BaTiO3薄膜,在(001)和(002)方向上都出现强度很高的尖锐衍射峰,具有较好的结晶质量和较小的表面粗糙度,原子力显微镜测定出薄膜的表面粗糙度为0.563nm.

双通道视觉质量系统评估不同方位白内障透明角膜切口手术疗效

目的探讨不同方位白内障透明角膜切口手术疗效以及双通道视觉质量分析系统在白内障手术前后视觉质量评估中的应用。方法收集白内障超声乳化联合囊内人工晶状体植入术患者共64例64眼,根据术中透明角膜切口的位置分为A组(透明角膜切口位于双眼颞侧)和B组(采用正上方透明角膜切口)。所有入选病例均行标准对数视力评估,双通道视觉质量分析系统检测。比较两组视力、MTF截止空间频率(MTF cut-off)、斯特列尔比值(strehl ratio,SR)、客观散射指数(objective scattering index,OSI)值及对比度为100%、20%、9%时的OQAS值(OQAS value,OV100%、OV20%和OV9%)。结果所有患者术后1d、1周裸眼视力及最佳矫正视力均逐渐上升,较术前差异均有统计学意义(P<0.05),1周后视力逐渐趋于稳定;其中A组术后1d、1周裸眼视力及最佳矫正视力均高于同时间点B组患者,差异均有统计学意义(均为P<0.05)。术后1个月及3个月两组间裸眼视力及最佳矫正视力无明显差异(P>0.05)。术后1d及1周两组患者OSI值均较术前逐渐下降,各时间点比较差异均有统计学意义(均为P<0.05),其中A组术后1d(2.81±0.89)及1周(1.98±0.73)OSI值明显低于B组术后1d(3.46±1.17)及1周(2.61±1.20)(均为P<0.05)。两组患者术后1个月及3个月与术后1周比较OSI值均无明显差异(均为P>0.05)。术后1d、1周、1个月及3个月两组患者OV9%值均较术前逐渐上升,各时间点比较差异均有统计学意义(均为P<0.05),其中A组术后1d(0.29±0.09)、1周(0.33±0.12)、1个月(0.37±0.14)及3个月(0.42±0.17)均明显高于B组术后1d(0.24±0.10)、1周(0.27±0.09)、1个月(0.31±0.09)及3个月(0.34±0.14)(均为P<0.05);所有患者术后各时间点MTF值、SR值、OV100%值、OV20%值与术前比较差异均无统计学意义(均为P>0.05)。结论白内障术中采用颞侧角膜切口,术后眼内散射小,视力恢复快,视觉质量高,远期效果有待进一步研究。双通道视觉质量分析系统能进一步量化视觉质量参数,在视觉质量评估方面具有一定优势。

视觉质量分析系统(OQAS-Ⅱ)在青少年人群中测量重复性研究

目的评估双通道视觉质量分析系统(optical quality analysis system,OQAS)-Ⅱ测量青少年近视人群视觉质量的重复性。方法采用前瞻性研究。于2013年5月至10月在天津医科大学眼科医院近视防控门诊就诊的患者中随机选取8~16(12.03±2.56)岁32例(32只右眼,男16名,女16名)患者为研究对象,屈光度为-1.00^-5.75(-3.77±1.78)D,散光度数为(-0.45±0.57)D。每位患者使用OQAS-Ⅱ检测3次,检查间隔5 min,由同一位有经验的检查者完成操作。OQAS-Ⅱ检查包括:调制传递函数(modulation transfer function,MTF)截止频率、客观散射系数(objective scatter index,OSI)、不同对比度下OQAS-Ⅱ值(OV100%、OV20%、OV9%)。测量视觉质量时统一使用4.0 mm瞳孔直径。统计分析使用SPSS 22.0软件,可重复性统计学指标评估使用:组内标准差Sw、组内变异系数CVw、组内相关系数ICC、重复性系数CR、相对重复性RR。ICC使用双侧混合作用模型。结果 3次测量的MTF截止频率为(30.97±12.49)c·d-1,OSI为0.80±0.82,OV100%为1.03±0.30,OV20%为1.04±0.33,OV9%为1.11±0.36。重复性检验的参数分别为:ICC:MTF截止频率为0.96 c·d-1,OSI为0.97,OV100%为0.94,OV20%为0.94,OV9%为0.93;CVw:MTF截止频率为0.08 c·d-1,OSI为0.18,OV100%为0.08,OV20%为0.08,OV9%为0.09;CR:MTF截止频率为6.83 c·d-1,OSI为0.39,OV100%为0.21,OV20%为0.23,OV9%为0.26;RR:MTF截止频率为0.22 c·d-1,OSI为0.49,OV100%为0.21,OV20%为0.22,OV9%为0.24。结论 OQAS-Ⅱ对于青少年近视人群视觉质量检测的重复性良好,适合用于临床评估青少年的视觉质量。

轴向温差对空间遥感器光学系统成像质量的影响

利用有限元分析计算了轴向温差对主、次镜面形的影响,对光学系统成像质量进行了评价。用PATRAN软件建立有限元模型,用NASTRAN/NT有限元分析软件完成温度场的分析计算。用Zernike多项式曲面拟合系数表示轴向温差对主、次镜面形的影响,通过ZEMAX软件分析对光学系统成像质量的影响,实现了热分析与光学分析的接口。结果表明:轴向温差不仅使光学系统产生像面位移—离焦,而且将产生各种像差,降低光学系统的成像质量,所以在调焦的同时,必须采取温控措施。最后给出了轴向温差具体的温控指标,主镜的轴向温差为0.8℃,次镜为1.0℃,主、次镜之间为3.0℃。