法国推出新防雾镜片 帮助眼镜保持清晰

Whether slaving over a hot stove or simply stepping outside on a cold day, those who wear spectacles have long experienced the frustration of fogged-up lenses.

But such steamy moments – which usually happen when lenses are colder or warmer than the air around them – could be wiped out with the invention of non-fogging glasses.

The lenses are coated on either side with a material that is extra-attractive to water. Their inventors say this means that when condensation gathers, it becomes an invisible film rather than fog, leaving the lenses clear.

The Optifog lenses were designed by Essilor, the French firm that created the world's first varifocals in 1959.

It believes the new lenses, priced from around ?200 depending on type and prescription, will be of most benefit to cooks, sports enthusiasts such as runners and cyclists, and medics who wear face masks.

The lenses are available in single vision, varifocal and sun-lens forms. They need to be sprayed with a chemical solution every week to keep the fog-repellent surface working.

The solution costs about ?5 a bottle and around four will be needed for the two-year lifetime of the lenses, which have just gone on sale.据英国《每日邮报》11月30日报道，无论是在热气腾腾的炉灶前忙碌，还是仅仅在寒冷的天气里走出屋门，戴眼镜的人都经历过镜片起雾的困扰。

但是随着防雾眼镜的发明，这种水汽蒙蒙的时刻——通常是由于镜片本身比周围空气温度低或者高——将会彻底终结。

镜片的两边都涂上了一种吸水能力特别强的材料。发明者说，这意味着当冷凝的水汽聚集在一起时，会形成一层不可见的薄膜，而不是雾气，镜片依然会很清晰。

这款名为“Optifog”的防雾镜片是由法国依视路公司设计的，这家公司曾在1959年推出世界首款变焦距镜片。

基于它的特征和材料，这种新的镜片售价大约在200英镑左右，人们认为它将会非常有利于厨师、运动爱好者，比如爱跑步或是骑自行车的人，以及那些戴口罩工作的医务人员。

这种镜片有单光、变焦、太阳镜三种形式，使用时需要每周在镜面上喷洒一种化学溶剂，才能保持防雾表面持续有效。

溶剂售价大约每瓶5英镑，镜片使用两年约需要四瓶，该溶剂已经开始在市面上销售。