Are there several kinds of LED now? A few years back they all looked like this:
(http://www.djtechtools.com/wp-content/uploads/2009/08/300px-LED_Labelled.svg.png)
But more and more seem to have some kind of EL thing going on in the middle, these tend to be superbright jobbies?
(http://www.ultraleds.co.uk/images/u1110off.jpg)
the way they work is the same, but the component packaging is a little different.