NOTE The difference in prismatic refractive power specified foran eye-protector depends not only on the prismatic refractive powerof each ocular, but also on the position of the optical axis of theocular in relation to the axis of vision, and therefore the shapeof the frame. It is therefore necessary to use replacement ocularsfor which the difference in prismatic power remains within thepermissible tolerance limits for the frame in question.
应采用EN 167:2001中3.2规定的方法，在眼睛的视觉中心测量覆盖双眼的已安装或未安装眼镜的屈光力特性。表3给出了无矫正效果的眼的容许公差。7.1中定义了具有矫正效果的眼睛顶点功率的允许偏差。2.1.1.不允许出现与3级相对应的偏差。
注：为护目镜指定的棱镜折射力的差异不仅取决于每个眼睛的棱镜折射力，还取决于眼睛光轴相对于视觉轴的位置，也取决于框架的形状。有必要使用棱镜功率差保持在所述框架容许公差范围内的替代眼镜。
1.2.1.3 Cover plates盖板
The refractive powers of cover plates shall comply with thetolerances for optical class 1 given in Tables 2 and 3.盖板的折射率应符合表2和表3中给出的光学等级1的公差。
1.2.2 Transmittance透射比
1.2.2.1 Oculars without filtering action无过滤作用的目镜
防护面罩只属于PPE II类产品，需要欧盟公告号机构Notified Body进行Module B形式检验，颁发B证书。那么在申请CE知识分享的过程中，防护面罩需要满足哪些要求呢?下面由上海郜盟知识分享工程师为您专业解读。
Basic, particular and optional requirements.防护面罩CE知识分享基本、特殊和可选要求
所有防护面罩都要满足基本要求。
根据其预期用途，应满足对应的一项或多项特殊要求。
可选要求制造企业可自行选择。
Basic requirements 基本要求
1.1 Field of vision
The size of the field of vision is defined in conjunction with theappropriate head-form described in clause 17 of EN168:2001.
视野大小的定义与EN 168:2001第17条中描述的适当头型相结合。
Eye-protectors shall exhibit a minimum field of vision defined bythe two ellipses in Figure 1 when placed and centered at a distanceof 25 mm from the surface of the eyes of the appropriate head-form.The horizontal axis shall be parallel to and 0,7 mm below theheight of the line connecting the centres of the two eyes.
当将护眼器放置在距离适当头型眼睛表面25mm的中心位置时，应显示如图1中两个椭圆所定义的Zui小视野。横轴应平行于连接两眼中心的线的高度0.7毫米以下。
The horizontal length of the ellipses shall be of 22,0 mm, thevertical width of the ellipses shall be 20,0 mm. The centredistance of the two ellipses shall be d =c + 6 mm, where c is thepupillary distance. The pupillary distance is 64 mm for the mediumhead-form and 54 mm for the small head-form, if not specifieddifferently by the manufacture.
椭圆的水平长度应为22.0毫米，垂直宽度应为20.0毫米。两个椭圆的中心距离应为d =c +6mm，其中c为瞳孔距离。瞳孔距离为64毫米为中等头部形式和54毫米为小头部形式，如果没有指定不同的制造商。
The test shall be carried out in accordance with clause 18 of EN168:2001.
测试应按照EN 168:2001条款18进行。
防护面罩视野要求-CE知识分享-上海郜盟
1.2 Optical requirements光学要求
1.2.1 Spherical, astigmatic and prismatic refractivepowers球面、像散和棱镜折射率
The refractive powers of oculars shall be measured by the referencemethods specified in clause 3 of EN 1 67:2001. This clause refersalso to an optional method for use in specific circumstances; thedetails of this method are given in annex A of EN 1 67:2001. 应采用EN1 67:2001第3条规定的参考方法测量眼睛的屈光力。本条款还提及了在特定情况下使用的可选方法；EN 167:2001附录A中给出了该方法的详细信息
1.2.1.1 Unmounted oculars covering one eye覆盖一只眼睛的未安装眼镜
The refractive power characteristics of unmounted oculars coveringone eye shall be measured by the method specified in 3.1 of EN 167:2001 (non-corrective oculars), and by the methods specified inEN ISO 8980-3 (corrective oculars).
The permissible tolerances for oculars without corrective effectare given in Table 2.
The permissible deviations for the vertex powers of oculars withcorrective effect are specified in EN ISO 8980-1 and EN ISO 8980-2.Oculars that comply with EN ISO 8980-1 and EN ISO 8980-2 shall becategorized as class 1.
For class 2, the deviations in vertex refractions may be 0,06 m -1higher than for class 1.
应采用EN 1 67:2001（非矫正视力）3.1中规定的方法和EN ISO8980-3（矫正视力）中规定的方法测量覆盖一只眼睛的未安装视力的屈光力特性。
表2给出了无矫正效果的眼的容许公差。
EN ISO 8980-1和EN ISO 8980-2中规定了具有矫正效果的目镜顶点功率的允许偏差。符合EN ISO8980-1和EN ISO 8980-2的眼睛应归类为1级。
对于2类，顶点折射的偏差可能比1类高0.06 m-1。
1.2.1.2 Mounted oculars and unmounted oculars covering botheyes安装的目镜和未安装的目镜覆盖双眼
The refractive power characteristics of mounted oculars orunmounted oculars covering both eyes shall be measured by themethod specified in 3.2 of EN 1 67:2001 at the visual center of theocular. The permissible tolerances for oculars without correctiveeffect are given in Table 3. The permissible deviations for vertexpowers of oculars with corrective effect are as defined in 7.1 .2.1.1 . Deviations that would correspond to class 3 shall not bepermitted.
