A few weeks ago I came across an almost new, Valeo brand, LED headlamp assembly. This one was from a BMW, but as it was a Valeo item, it is probably very similar in design to the headlamps that go in a lot of new cars. When complete in its enclosure there is nothing much to see, really. So, I did what any person would do, I sawed it in half to have a look.
Beyond all the 'Angel Eyes' BMW bits, you eventually get to the main beam unit, pictured below. I should add that the two halves of the outer headlamp assembly are very strongly stuck together with mastic/sealant - these inner parts are not serviceable. You would only see these bits after you had destroyed the outer container.
The main beam unit has five LEDs, three for low beam and two for high beam, I assume. The large heatsink sits inside of the main headlamp enclosure.
Hopefully you can what-is-doing-what in the photos - these pics were a bit rushed. The LEDs lie horizontally on their heatsink and shine into the reflector, to be then turned through 90 degrees, shine past the 'beam cutoff mask' and then through the plastic lens.
Nice, innit?