kicad-developers team mailing list archive

[Cirilo Bernardo <cirilo_bernardo@xxxxxxxxx>]

----- Original Message -----

> From: Dick Hollenbeck <dick@xxxxxxxxxxx>
> To: KiCad Developers <kicad-developers@xxxxxxxxxxxxxxxxxxx>
> Cc: 
> Sent: Tuesday, June 11, 2013 6:37 AM
> Subject: [Kicad-developers] SMT LEDs on board back side,
	but showing through a hole
> 
> 
> http://electronicdesign.com/boards/smt-leds-emit-light-through-holes
> 
> Is there another way to do this with SMT without using this special product?
> 
> Do SMT LEDS light on their backside?  If show, could a person not use a normal 
> SMT LED for
> this and simply put a NPTH in the middle of the two pads?
> 
> Thanks,
> 
> Dick
> 


SMT LEDs generally do not emit light behind them; there is usually a reflector of some sort (remember the rather obvious reflectors in the large clear encapulated thru-hole LEDs).   For a better picture; have a look at some datasheets from Osram (top-emitting and bottom-emitting LEDs; there are images revealing some details of the encapsulation):

http://catalog.osram-os.com/catalogue/catalogue.do?favOid=000000000002e87f00030023&act=showBookmark


http://catalog.osram-os.com/catalogue/catalogue.do?favOid=000000000001f73300070023&act=showBookmark


- Cirilo