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Old 08-17-2011, 12:20 PM   #1
hgt2y7lkt
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Default 劣质眼镜易引发散光

眼镜已成为许多人生活中不可缺少的一部分,目前眼镜市场已具有一定规模,但尚未完全规范化,市面上仍有许多 劣质眼镜被出售给消费者。所以消费者选购眼镜一定要慎重。

一般来说,劣质眼镜由地下工厂无证生产,设备简陋,成本很低,所以价格特别低廉。在镜片材料方面,劣质眼镜 树脂基质不纯,可引起视物变形或眩晕。色散效应大,易致视疲劳。内部有不良应力存在,抗冲击能力差,易碎。 透光率低,光度分布不均匀。折射率达不到其宣传的标准,150-5858-0503,夸大镜片的超薄程度。另外,不能防紫外线或只能防止少量的紫外线。

同时,在镜片表面处理,劣质品表面处理不好,无加硬防花功能。镀膜技术差,易脱膜。膜层达不到要求,减反射 能力低,无防水、防污、防雾等特殊功能。

在镜架材料方面,劣质眼镜金属冶炼工艺差,纯度低,含杂质多,甚至可能含有对头部有害的放射性元素,比重较 大,对鼻梁压迫作用强,加湿器批发价格,不利于青少年儿童鼻梁部发育。弹性差,质脆易断裂。表面光泽和色泽差,耐腐蚀性差,易生锈,易变色。另外 也有对皮肤刺激大、易致过敏,质软、易变形等。

对于镜架加工工艺,劣质眼镜表面粗糙不平,颜色灰暗。电镀技术不佳,易脱色。电焊技术差,焊点 不牢,光波炉价格,易脱焊。铰链和螺纹易损坏。

劣质眼镜在装配上也达不到国家质量标准。双眼镜片光心一高一低,偏左或偏右,瞳距不准确,散光轴位不准确等 ,均会造成不合适的棱镜效应,影响正常视觉功能。
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