激光辐射对人眼的危害--中英版.doc

激光辐射对人眼的危害The harms of Laser radiation to human eyes

　　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，而使视网膜上的能量密度较角膜上入射能量密度提高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。
Because the characteristic of laser, it can make energy highly concentrated in space and in time. Through the eye’s refracting media that focusing on retina to form an image, then the incident energy density on retina can increase 104～105 than the incident energy density on cornea; The monochromaticity of laser is good, and the chromatic aberration is small on the ocular fundus. The above features can cause the damage of cornea or retina by very low laser radiation.

不同波长激光眼损伤部位The injured part of eyes by different wavelength lasers.

波长分区
Wavelength Division
波长范围(nm)
Wavelength Range(nm)
主要损伤部位
Mian Injured Part
紫外激光
UV laser
180-400
角膜、晶状体
Cornea, lens
可见激光
Visible laser
400-700
视网膜、脉络膜
Retina, choroid
近红外激光
Near-infrared laser
700-1400
视网膜、脉络膜、晶状体Retina, choroid, lens
中、远红外激光
mid-infrared laser, far infrared laser
1400-106
角膜
cornea

眼底对几种激光的有效吸收率
The effective absorptivity of several lasers by ocular fundus.

激光器
Laser
波长(nm)
wavelength
(nm)
吸收率(%)
absorptivity(%)
介质透过率Transmission media(%)
有效吸收率Effective absorptivity(%)
钕激光Neodymium laser
1064
12
42
5.04
红宝石
Ruby
694.4
56
96
53.7
氩离子
Argon ion
488-514
70
80
56
倍频
Frequency doubling Nd:YAG
532
74
88
65

包括视网膜色素上皮和脉络膜的吸收
Including the absorption/absorptivity of retinochrome epithelium and choroid.

激光损伤事故的主要症状
The main symptom of injury accident by laser.

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。
When the accident happens, most of wounded persons feel that flash suddenly appear before their eyes, then appear a facula or shadow of different colour and different size, few people feels impact on eyes. At the same time, their vision decline in different degrees. Severe cases can not see objects before their eyes clearly, some people appears dizzy and photophobia for many hours after injured.

激光眼事故损伤照射统计
The statistics of eyes’injury accident by laser radiation.

激光器
Laser
发射方式
Radiation pattern
波长
wavelength（nm）
受伤人数
Number of injured people
损伤眼次
Number of injury on eyes
Nd：YAG
超短脉冲
Utrashort pulse
1064
1
1
Nd：YAG
巨脉冲
Giant pulse
1064
23
24
Nd：YAP
巨脉冲
Giant pulse
1064
1
1
红宝石
长脉冲
Long pulse
694.4
11
12
染料
巨脉冲
Giant pulse
560～590
3
3
Ar+
连续
continuous
488～514.5
1
1
He-Cd
连续
continuous
441.6
1
1
不详
unknown
不详
unknown
不详
unknown
4
4
合计
summation

45
47
数据摘自《激光辐射伤医学防护》
Data taken from
《Laser radiation injury protection in medicine》

原因与教训
Reason and lesson

一、 工作中未采取眼防护措施
1. Without adopting eyes protective measures during working.
二、 缺乏安全的工作环境
2. Lack of security working atmosphere.
三、 思想麻痹
3. Slackening of vigilance.
四、 激光器误触发
4. Laser false triggering.
五、 在激光临床眼科治疗中，未能严格控制治疗能量
5. When under clinical ophthalmology laser treatment, it can not strictly control the curing energy.

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。
Working under operating laser environment for long time, the eyes of operator will have long term effect. When operating and using laser, even there is no injury accident happens by laser radiation directly, but the rays emitted by laser can cause micro reflection through other objects or walls, people who working long term under this environment will cause high incidence of cataract.

典型脉冲激光器危害类别
Typical harm classification of pulsing laser

波长范围
Wavelength range
激光器
Laser
脉宽
Impulse width
1 class
2 class
4 class
180～400nm
四倍频quadruple frequency Nd:YAG
ns
58.0uJ
≤10J/cm2
＞10J/cm2
400～700nm
倍频frequency multiplication Nd:YAG
ns
≤0.2uJ
＞0.2uJ
＞85mJ/cm2

≤85mJ/cm2

红宝石
ruby
ms
≤0.4uJ
＞0.4uJ
＞3.1J/cm2

≤3.1/cm2

染料可调谐
Tunable dye
us
≤0.2uJ
＞0.2uJ
＞0.31J/cm2
700～1mm
Nd:YAG
ns
≤2uJ
＞2uJ
＞0.42J/cm2

≤0.42J/cm2

Er Laser
ns
≤8.0mJ
＞8.0mJ
＞10J/cm2

CO2
ns
≤80uJ
＞80uJ
＞10J/cm2

几种典型激光源人眼防护所要求的最低光密度值
The minimum optical density value of some typical lasing light emitter that protecting human eyes required.

激光器
Laser
发射方式
Radiation pattern
输出功率/能量
delivered power/energy
照射限值
Irradiate limit value
光密度
optical density
倍频frequency multiplication Nd：YAG
巨脉冲
Giant pulse
100 mJ
5.0×107J/cm2
6.0
Cu smoke
连续continuous
5 W
1.8×10-3W/cm2
4.1
Ar+
连续continuous
5 W
1.8×10-3W/cm2
4.1

连续continuous
50 mW
1.8×10-3W/cm2
2.1
Nd：YAG
连续continuous
80 mW
9.6×10-3W/cm2
4.6

Long pulse
400 mJ
5.0×10-6J/cm2
5.6

Giant pulse
100 mJ
5.0×10-6J/cm2
5.0
CO2
连续
continuous
80 W
5.6×10-1W/cm2
2.9

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。
As the laser technology is widely used in military and civilian areas, peoples pay more and more attention to the laser protection technology, and the types of materials to make laser protection also increase. Now, there are three types of laser protection materials from the point of view of the protection principle: first, the laser protection based on the linear optics, which contains the absorption-type, the reflection-type, and the absorption-reflection-type. Second, the laser protection based on the nonlinear optics, which’s principle is third-order nonlinear optical effect, and it includes nonlinear absorption, nonlinear refraction, nonlinear scattering, and nonlinear reflection. Third, laser protection based on the phase transition theory.
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题，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。
The laser has many characteristics, such as exceeding direction, extreme monochromaticity, and good coherence, which cause the laser used widely in military, industrial and medical areas. But, these laser’s characteristics also make it become a threat to the human’s body, like the eyes. Eyes are the most sensitive organ in our body, the energy density of light focused by our eyes will increase by 105 times the non-focused light, so the low dose exposure could damage our retinal seriously, and it lead to vision loss and even blindness. How to do some effectively laser protection has become a great concern in the world, and many countries have enacted the relevant laser protection standards. In 1962, US had made a number of irradiating laser safety limits, and now there are some compulsive standards about laser safety in China: CJB-2408-95 laser protective eyewear protective performance test methods, GJB-1762-93 physical protection requirements for laser protective eyewear, JB/T 5524-91 lab laser safety rules.

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/T 5524-91 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。
There are many kinds of laser goggles, and there are lots of differences within each others, such as different materials, different principles, and different applications. So if the laser needs to be protected effectively, the laser goggles must be selected according to the specific requirements. When we choose the laser goggle, the first step is to define the maximum irradiance or the maximum exposure according to the peak output power, beam diameter, pulse time, and other parameters of the laser, and then we will define the minimum optical density according to the wavelength and the maximum permissible radiation of exposure time. In conclusion, the conditions of choosing suitable laser goggles include:
1. the maximum irradiance Hmax(J/m2) or the maximum exposure Emax(W/m2)
2. the wavelength
3. the minimum optical density Dmin under a corresponding wavelength
4. the heterogeneity, asymmetry, and incident angle effect of the goggle
5. the capability of anti-laser radiation
6. the visible light transmittance
7. the structure and shape