The subject of the present invention is a solid material in the form of a microperforated sheet transparent to light of wavelengths in the visible and infrared, characterized in that the mean distance between two immediately neighbouring perforations is at least 5, and preferably 7 .mu.m, and is so over...http://www.google.fr/patents/US6120875?utm_source=gb-gplus-shareBrevet US6120875 - Transparent micro perforated material and preparation process
Transparent micro perforated material and preparation process
