法國推出新防霧鏡片 幫助眼鏡保持清晰
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.據英國《每日郵報》11月30日報道，無論是在熱氣騰騰的爐竈前忙碌，還是僅僅在寒冷的天氣裏走出屋門，戴眼鏡的人都經歷過鏡片起霧的困擾。
但是隨着防霧眼鏡的發明，這種水汽濛濛的時刻——通常是由於鏡片本身比周圍空氣溫度低或者高——將會徹底終結。
鏡片的兩邊都塗上了一種吸水能力特別強的材料。發明者說，這意味着當冷凝的水汽聚集在一起時，會形成一層不可見的薄膜，而不是霧氣，鏡片依然會很清晰。
這款名爲“Optifog”的防霧鏡片是由法國依視路公司設計的，這家公司曾在1959年推出世界首款變焦距鏡片。
基於它的特徵和材料，這種新的鏡片售價大約在200英鎊左右，人們認爲它將會非常有利於廚師、運動愛好者，比如愛跑步或是騎自行車的人，以及那些戴口罩工作的醫務人員。
這種鏡片有單光、變焦、太陽鏡三種形式，使用時需要每週在鏡面上噴灑一種化學溶劑，才能保持防霧表面持續有效。
溶劑售價大約每瓶5英鎊，鏡片使用兩年約需要四瓶，該溶劑已經開始在市面上銷售。
