Actually, finding more lumens among the lighter weight projectors has gotten tougher. A few years ago, there were a handful of under 2.5 pound conventional projectors. I'm not sure any remain on the market. Manufacturers learned that an extra half to one pound was not an important issue for most shoppers of the lightest projectors, that price, and features were often more important, so there are fewer of the lightest. Now, however, pocket projectors may step into that category, as they achieve fairly respectable brightness from a presentation standpoint.

As you can see, the projector industry started off pretty dim, at least per pound. It continues to deliver more lumens per pound, and per size, but, these relatively new classes of lightweight portable projectors with solid state light soures, while still far dimmer per pound, are improving dramatically, from year to year. For 2010, we've reviewed a 50 lumen model that's definitely a pico sized projector, and it weighs in at 0.5 pounds. I would be impressed if we see a 100 lumen pico (around a half pound) by the end of 2011. see perhaps a 1/2 pound projector with more than 100 lumens... Meantime, the improvement in one year is significant for the pico class of projectors. Note: in fairness, the one pico capable of 50 lumens this year, only can do it on AC, or using the optional external battery. 20 lumens is its max on its standard battery.