Rene - Visible spectrum opacity/reflectance is not necessarily representative of properties at IR or UV wavelengths. Each material will exhibit some relatively unique absorption/reflection properties throughout the 'optical' EM spectrum. For example, polycarbonate is transparent or translucent in the visible spectrum, but in some IR acts as a bandstop filter and can provide a degree of eye protection.
It could be that the only differences are the color additives in the molding materials. It could be that some dies have a premold before they're final package molded (though this seems unlikely), or might have some other IR opaque film applied before molding. Could be the color additive itself helps block some unwanted group of frequencies. Regards, Peter L. Tarver, PE [email protected] > From: Rene Charton/Twn/TUV > Sent: Thursday, June 01, 2006 1:31 AM > > On the other hand, > would the white interior of a white opto-coupler not provide > additional > reflection to the light generated by the diode, > and thus enhance the sensitivity? > (for circuits that are built into a black enclosure? ) > > Rgds > > Rene Charton > CONFIDENTIALITY This e-mail message and any attachments thereto, is intended only for use by the addressee(s) named herein and may contain legally privileged and/or confidential information. If you are not the intended recipient of this e-mail message, you are hereby notified that any dissemination, distribution or copying of this e-mail message, and any attachments thereto, is strictly prohibited. If you have received this e-mail message in error, please immediately notify the sender and permanently delete the original and any copies of this email and any prints thereof. ABSENT AN EXPRESS STATEMENT TO THE CONTRARY HEREINABOVE, THIS E-MAIL IS NOT INTENDED AS A SUBSTITUTE FOR A WRITING. Notwithstanding the Uniform Electronic Transactions Act or the applicability of any other law of similar substance and effect, absent an express statement to the contrary hereinabove, this e-mail message its contents, and any attachments hereto are not intended to represent an offer or acceptance to enter into a contract and are not otherwise intended to bind the sender, Sanmina-SCI Corporation (or any of its subsidiaries), or any other person or entity. _____________________________________________________________________________ Scanned by Sanmina-SCI eShield _______ _____________________________________________________________________ - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas [email protected] Mike Cantwell [email protected] For policy questions, send mail to: Jim Bacher: [email protected] David Heald: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
