The invention contemplates a method for making a disposable element adapted for selective placement in the path of laser beam delivery to the cornea. The element carries a membrane of uniform thickness which is opaque to the laser-beam and which is subject to ablation when exposed to the laser ...http://www.google.co.uk/patents/US5807379?utm_source=gb-gplus-sharePatent US5807379 - Ophthalmic method and apparatus for laser surgery of the cornea
