What are 1st & 2nd generation of Laser Eye Surgery?

The first generation of laser eye surgery was initially called PRK or LASEK.The laser is applied directly to the surface of the eye.This results in quite an amount of discomfort and watering and a slow visual recovery.For that reason,a second generation of laser eye surgery called LASIK was developed.The first step is to create a flap on the surface of cornea which is peeled open.The second step is to use a laser to sculpt the glasses prescription into the cornea,thereby correcting the vision.The flap is then placed back & vision recovers rapidly within 24 hrs with minimal discomfort & only mild watering from the eye.