Nd: YAG laser for a Biolaser-1 ophthalmic system

摘要

An ophthalmic surgical instrument is presented. It contains a specific Q-switch YAG:Nd laser, an optical stereomicroscope, two red output laser diodes and a digital system for optical processing of the microscope images. As Q-switch, a Cr~(4+): YAG crystal is used. It works in monopulse or double pulse regime. Four red spots mark the optical object plane. The laser beam is sent in the central part, between the four spots and is focused at 150 microns behind the optical plane to reduce the risk of pitting the lens when performing posterior capsulotomies. In order to obtain eleven different energy levels in the (2/10)mJ domain, eleven attenuators are used. The laser ophthalmic system must fulfill many precautions. The energy level, the pulse length and the used attenuators must have such values to eliminate every undesired effect in the medical applications. This instrument has an important application in posterior capsulotomies and posterior membranectomies.