In one embodiment, the present invention provides a microlens having very small focal length. The present invention also provides a non-planar microstructure having a covering layer which is slowly oxidizing or substantially free of oxygen. The present invention also provides methods for forming such...http://www.google.com.au/patents/US6365237?utm_source=gb-gplus-sharePatent US6365237 - Method of making non-planar micro-optical structures
