You still need a cooling fan with an LED for equivalent lumens. It's just that it vents out the back. There are projectors out now with this. You sometimes see them in storefronts projecting cutout images onto streets etc. I've seen one at a show. Kind of cool, but low-grade optics for projecting illustrations, not fine detailed slides. The white balance would likely need an intermediary. It's the optics of slide projection that are the difficult part.
Originally Posted by ME Super