----- Original Message ----- From: David VanHorn > >A sheet of white paper over a 8mm hole will do fine. Take medium heavy > >paper (90+g). Cover the outside with a microscope slide if you are > >paranoid (ordinary glass stops most dangerous UV). > > Indeed, despite claims of glasses manufacturers to the contrary. Um... don't a LOT of glasses use plastic lenses? Does that change anything? I can't say much for the UV that penetrates the atmosphere, but the manual for my UV EPROM eraser says that most glass does not let the specific UV erasing light spectrum needed to erase chips, that's why the eraser bulbs need quartz for the "glass" material. So at the very least, the erasing part of the spectrum will be blocked. Where can I look up info about ordinary glass (or plastic) blocking _all_ the nasty UV? Jeff -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body