Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!rutgers!cmcl2!rocky8!cucard!ccnysci!sukenick From: sukenick@ccnysci.UUCP (George Sukenick) Newsgroups: sci.electronics Subject: Re: Looking for Blue LEDs (Found!) Keywords: correction Message-ID: <891@ccnysci.UUCP> Date: 26 Sep 88 17:00:51 GMT References: <1182@nmtsun.nmt.edu> <44300009@uxe.cso.uiuc.edu> Reply-To: sukenick@ccnysci.UUCP (George Sukenick) Organization: City College of New York Lines: 20 >Doublers are not inefficient. [60-90%] [expensive ca. $2700] >They do need large powers (say 50 watts to get 60% efficiency). >Multiphoton absorption is to be avoided like the plague - if it happens, >the crystal EXPLODES! Whoops, $2700 down the drain! >These things work on nonlinear index of refraction, not absorption. Absolutely right! Thanks for the correction. I had said 'absorption' when it should have been about 'virtual levels' and I had forgotten about phase matching (which brings efficiency up) (Its been a while since Yariv and Born & Wolf....) I hope that no one blew up anything on my account :-)