Mini projectors were originally battery powered. However, today, we are more likely to see a mini projector with an external battery pack to run off of both external AC power and battery. The original successful mini projector, the Mitsubishi PK20, dates back to about 2006. This projector was used by missionaries for church work.
Missionaries would travel to lots of villages in developing countries, and because they were never sure if they would have a power source for their presentations, they needed battery powered projectors.
So we have seen some changes. Most Mini projectors today are now sporting 100+ lumens, therefore requiring AC power. But then again, they also have the capability of doing small group presentations of rather reasonable quality, which the smaller, dimmer pico projectors can’t yet claim.
