The M2 relies on an LED RGBB light source designed to deliver a bright color image from a compact package. Due to its light source, the M2 can deliver 500 ANSI Lumens of brightness and reproduce 125% of the Rec.709 color gamut.
There is a theory the LED light sources also make images look brighter than measured ANSI Lumen brightness. ViewSonic states projector can output "1,200 LED lumens" because it should look as bright as a 1200 lumens lamp-based projector.
The light source also makes the projector essentially maintenance-free, and offers over 30,000 hours of use. That is the equivalent of almost 3.5 years of 24/7 use, so it should be very sufficient for the average user. Along with minimal maintenance, lamp-free projection is more environmentally friendly than other options, as there is no mercury used in the manufacturing process, and the projector will consume less power than a typical LCD TV.