激光辐射对人眼的危害 中英版

激光辐射对人眼的危害 中英版 激光辐射对人眼的危害TheharmsofLaserradiationtohumaneyes 由于激光的特性，可使能量在空间和时间上高度集中。通过眼的 屈光介质聚焦在视网膜上形成影像，104,105;激光单色性好，在眼 底的色差小。上述特点致使极低的激光能量照射即可引起眼角膜或视 网膜的损伤。 Becausethecharacteristicoflaser,itcanmakeenergyhighlyconcentratedinspaceandintime.Throughtheeye’ srefractingmediathatfocusingonretinatoformanimage,thentheincidentenergydensityonretinacanincrease104, 105thantheincidentenergydensityoncornea;Themonochromaticityoflaserisgood,andthechromaticaberrationissmallontheocularfundus.Theabovefeaturescancausethedamageofcorneaorretinabyverylowlaserradiation. 不同波长激光眼损伤部位 Theinjuredpartofeyesbydifferentwavelengthlasers. 波长分区WavelengthDivision紫外激光 波长范围(nm)WavelengthRange(nm)180-400 主要损伤部位MianInjuredPart角膜、晶状体Cornea,lens视网膜、 脉络膜Retina,choroid视网膜、脉络膜、晶状体Retina,choroid,lens UVlaser 可见激光 ——————————————————————————————————————————————— Visiblelaser 近红外激光 400-700 Near-infraredlaser 中、远红外激光mid-infraredlaser,farinfraredlaser 700-1400 1400-106 角膜cornea 眼底对几种激光的有效吸收率 Theeffectiveabsorptivityofseverallasersbyocularfundus. 波长(nm) 介质透过率 有效吸收率 激光器Laser钕激光Neodymiumlaser红宝石Ruby氩离子Argonion TransmissionEffectivewavelength absorptivity(%) (nm)media(%)absorptivity(%) 吸收率(%) 106412425.04 694.4488-514 5670 ——————————————————————————————————————————————— 9680 53.756 倍频 Frequency doubling Nd:YAG 包括视网膜色素上皮和脉络膜的吸收 Includingtheabsorption/absorptivityofretinochromeepitheliumandchoroid. 激光损伤事故的主要症状 Themainsymptomofinjuryaccidentbylaser. 事故发生时，多数受伤者感到眼前突然闪光，继而出现一个不同 颜色、不同大小的光斑或暗影，个别人眼部有冲击感，与此同时，视 力出现不同程度的下降，重者短时间内不能分清眼前物体，有的伤后 出现数小时的目弦及畏光。 Whentheaccidenthappens,mostofwoundedpersonsfeelthatflashsuddenlyappearbeforetheireyes,thenappearafaculaorshadowofdifferentcolouranddifferentsize,fewpeoplefeelsimpactoneyes.Atthesametime,theirvisiondeclineindifferentdegrees.Severecasescannotseeobjectsbeforetheireyesclearly,somepeopleappearsdizzyandphotophobiaformanyhoursafterinjured. ——————————————————————————————————————————————— 激光眼事故损伤照射统计 Thestatisticsofeyes’injuryaccidentbylaserradiation.受伤人数 Numberof injured people 1损伤眼次Numberofinjuryoneyes1532748865激光器Laser发射 方式Radiationpattern超短脉冲波长wavelength(nm)Nd:YAGUtrashort pulse 巨脉冲1064 Nd:YAGGiant pulse 巨脉冲10642324 Nd:YAPGiant pulse106411 红宝石长脉冲 Longpulse 巨脉冲694.41112 染料Giant pulse560,59033 Ar+连续continuous488,514.511 He-Cd 不详 ——————————————————————————————————————————————— unknown 合计 summation连续continuous不详unknown441.6不详unknown11444547 数据摘自《激光辐射伤医学防护》 Datatakenfrom 《Laserradiationinjuryprotectioninmedicine》 原因与教训 Reasonandlesson 一、工作中未采取眼防护措施 1.Withoutadoptingeyesprotectivemeasuresduringworking. 二、缺乏安全的工作环境 2.Lackofsecurityworkingatmosphere. 三、思想麻痹 3.Slackeningofvigilance. 四、激光器误触发 4.Laserfalsetriggering. 五、在激光临床眼科治疗中，未能严格控制治疗能量 5.Whenunderclinicalophthalmologylasertreatment,itcannotstrictlycontro lthecuringenergy. 长期在激光操作环境中工作者眼睛受到长期的影响。在操作和使——————————————————————————————————————————————— 用激光器时，即使没有直接被激光照射，造成伤害事故的发生。可是 激光器所放出的射线通过其他物体或者墙壁等产生的微量反射，长期 在这种环境中工作的人群，白内障的发病率极高。 Workingunderoperatinglaserenvironmentforlongtime,theeyesofoperatorwillhavelongtermeffect.Whenoperatingandusinglaser,eventhereisnoinjuryaccidenthappensbylaserradiationdirectly,buttheraysemittedbylasercancausemicroreflectionthroughotherobjectsorwalls,peoplewhoworkinglongtermunderthisenvironmentwillcausehighincidenceofcataract. 典型脉冲激光器危害类别 Typicalharmclassificationofpulsinglaser 波长范围 Wavelength range脉宽Impulse1classwidth2class4class激光器Laser 四倍频 180,400nmquadruple frequencyns58.0uJ?10J/cm2,10J/cm2 Nd:YAG倍频frequency 400,700nmmultiplication Nd:YAG ?85mJ/cm2 红宝石ruby ——————————————————————————————————————————————— ms ?0.4uJ ,0.4uJ?3.1/cm2 染料可调谐Tunabledye 700,1mm Nd:YAG us ?0.2uJ ,0.2uJ ,0.31J/cm2 ,0.42J/cm2 ,3.1J/cm2 ns ?0.2uJ ,0.2uJ ,85mJ/cm2 ns?2uJ,2uJ?0.42J/cm2 ErLaserCO2 nsns ?8.0mJ?80uJ ,8.0mJ,80uJ ,10J/cm2,10J/cm2 ——————————————————————————————————————————————— 几种典型激光源人眼防护所要求的最低光密度值 Theminimumopticaldensityvalueofsometypicallasinglightemitterthat protectinghumaneyesrequired.发射方式Radiationpattern巨脉冲Giantpulse连续continuous 连续continuous 连续continuous Nd:YAG 连续continuousLongpulseGiantpulse CO2 连续continuous 5W 1.8×10-3W/cm2 4.1 100mJ 5.0×107J/cm2 6.0 输出功率/能量deliveredpower/energy 照射限值Irradiatelimitvalue 光密度opticaldensity 激光器Laser倍频frequencymultiplication Nd:YAGCusmoke ——————————————————————————————————————————————— Ar+5W50mW 1.8×10-3W/cm21.8×10-3W/cm2 4.12.1 80mW400mJ100mJ 9.6×10-3W/cm25.0×10-6J/cm25.0×10-6J/cm2 4.65.65.0 80W5.6×10-1W/cm22.9 激光防护镜的选择 随着激光技术在军事、民用领域的广泛应用，激光防护技术越来 越受到人们的重视，激光防护材料的种类日益增多。从防护原理来看， 目前激光防护材料可分为三大类:一是基于线性光学原理的激光防护， 它包括吸收型、反射型和吸收/反射复合型;二是基于非线性光学原 理的激光防护，它主要利用三阶非线性光学效应，包括非线性吸收、 非线性折射、非线性散射和非线性反射;三是基于相变原理的激光防 护。 Asthelasertechnologyiswidelyusedinmilitaryandcivilianareas,peoplespaymoreandmoreattentiontothelaserprotectiontechnology,andthetypesofmaterialstomakelaserprotectionalsoincrease.Now,therearethreetypesoflaserprotectionmaterialsfromthepointofviewoftheprotectionprinciple:first,thelaserprotectionbasedonthelinearoptics,whichcontainstheabsorption-type,thereflection-type,andtheabsorption-reflection-type.Second,thelase——————————————————————————————————————————————— r protectionbasedonthenonlinearoptics,which’sprincipleisthird-ordernonli nearopticaleffect,anditincludesnonlinearabsorption,nonlinearrefraction,nonlinearscattering,andnonlinearreflection.Third,laserprotectionbasedonthephasetransitiontheory. 激光具有方向性强、单色性好、相干性好等特点，使得它在军事、 工业及医疗等领域都有着广泛的应用。但正是激光的这些特点对人体 也构成了极大的威胁。眼睛是人体对激光最敏感的器官，由于眼对光 的聚焦作用可使视网膜上能量密度增高105倍，因此低剂量照射就可 引起视网膜的严重损伤而导致视力下降直至失明。如何进行有效的激 光防护，成为人们极为关注的问，各国相应地制定了激光防护标准。 早在1962年美国就提出了一些激光安全辐照限。 Thelaserhasmanycharacteristics,suchasexceedingdirection,extrememonochromaticity,andgoodcoherence,whichcausethelaserusedwidelyinmilitary,industrialandmedicalareas.But,theselaser’scharacteristicsalsomakeitbecomeathreattothehuman’sbody,liketheeyes.Eyesarethemostsensitiveorganinourbody,theenergydensityoflightfocusedbyoureyeswillincreaseby105timesthenon-focusedlight,sothelowdoseexposurecoulddamageourretinalseriously,anditleadtovisionlossandevenblindness.Howtodosomeeffectivelylaserprotectionhasbecomeagreatconcernintheworld,andmanycountries——————————————————————————————————————————————— haveenactedtherelevantlaserprotectionstandards.In1962,UShadmadeanumberofirradiatinglasersafetylimits,andnowtherearesomecompulsivestandardsaboutlasersafetyinChina:CJB-2408-95laserprotectiveeyewearprotectiveperformancetestmethods,GJB-1762-93physicalprotectionrequirementsforlaserprotectiveeyewear,JB/T5524-91lablasersafetyrules. 现在我国使用关于激光安全的强制标准有: CJB-2408-95激光防护眼镜防护性能测试方法 GJB-1762-93激光防护眼镜生理卫生防护要求 JB/T5524-91实验室激光安全规则 激光防护镜有多种类型，所用材料不同，原理各异，应用场合也 不同。因此，要提供对激光有效防护，必须按具体使用要求对激光防 护镜进行合理的选择。选择防护镜时，首先根据所用激光器的最大输 出功率(或能量)、光束直径、脉冲时间等参数确定激光输出最大辐 照度或最大辐照量。而后，按相应波长和照射时间的最大允许辐照量 (眼照射限值)确定眼镜所需最小光密度值，并据此选取合适防护镜。 选择的具体条件主要有: 1、最大辐照量Hmax(J/m2)或最大辐照度Emax(W/m2); 2、特定的防护波长; 3、在相应防护波长的所需最小光密度值Dmin; 4、防护镜片的非均匀性、非对称性、入射光角度效应等; 5、抗激光辐射能力; 6、可见光透过率; ——————————————————————————————————————————————— 7、结构和外形。 Therearemanykindsoflasergoggles,andtherearelotsofdifferenceswithineachothers,suchasdifferentmaterials,differentprinciples,anddifferentapplications.Soifthelaserneedstobeprotectedeffectively,thelasergogglesmustbeselectedaccordingtothespecificrequirements.Whenwechoosethelasergoggle,thefirststepistodefinethemaximumirradianceorthemaximumexposureaccordingtothepeakoutputpower,beamdiameter,pulsetime,andotherparametersofthelaser,andthenwewilldefinetheminimumopticaldensityaccordingtothewavelengthandthemaximumpermissibleradiationofexposuretime.Inconclusion,theconditionsofchoosingsuitablelasergogglesinclude: 1.themaximumirradianceHmax(J/m2)orthemaximumexposureEmax(W/m2) 2.thewavelength 3.theminimumopticaldensityDminunderacorrespondingwavelength 4.theheterogeneity,asymmetry,andincidentangleeffectofthegoggle 5.thecapabilityofanti-laserradiation 6.thevisiblelighttransmittance 7.thestructureandshape ———————————————————————————————————————————————