Optical reading apparatus and method of reading data

摘要

This apparatus having an optical head ( 15 -FIG. 1 )) for reading data stored in an optical carrier ( 1 ) comprises: a light source constituted by a first laser ( 50 ) or master laser for illuminating said carrier, an optical mounting ( 58 ) for directing the reflected light from said carrier to a detection branch ( 65 ) in which a non-linear optical element ( 80 ) is placed. This non-linear optical element ( 80 ) improves the signal to noise ratio by its non-linear characteristic before detection by the usual detector ( 75 ). The invention can be used for DVD players and/or recorders.