Isn't the physical gap between transmitter and receptor very small and don't these devices use a narrow band of infrared?
I suspect package colour has nothing to do with optical performance or at best it's swamped by operating temperature effects. ====================================== Ralph McDiarmid, AScT Compliance Engineering Group Xantrex Technology Inc. From: [email protected] [mailto:[email protected]] On Behalf Of Powell, Doug Sent: Thursday, June 01, 2006 11:38 AM To: [email protected] Subject: RE: Why are some optocouplers white and some black? I have one bit of information to add to the mix. A co-worker, who is more an old-timer than I, recalls that when the translucency problem was solved it was during VDE approvals at some company whose name he does not recall. The story goes that, as proof that the problem was fixed they started using white bodies for the ICs instead of black. If true, it sounds a little like an advertising trick. If there are any opto-folks on this discussion group I would like to hear your perspective. Doug Powell, Staff Engineer Corporate Compliance Dept. Advanced Energy Industries Inc. From: Powell, Doug [mailto:[email protected]] Sent: Wednesday, May 31, 2006 11:03 AM To: [email protected] Subject: Why are some optocouplers white and some black? This is obviously a trivia question but I think is related to product safety. My recollection is that early on, some manufacturers designated white body optocouplers as the only type that had certain attributes, like agency approvals. It would seem that a white body would be more translucent and you risk falsely triggering the transistor. -Doug Doug Powell Advanced Energy Industries Inc. Fort Collins, Colorado USA - 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 - 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 - 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
