From the Desk of David Pogue - The New World of Pocket Projectors
here's a review of the 3M and Aiptek pocket projectors.
The 3M Micro Professional Projector MPro110 costs about $300 online, much less than the Optoma ($430). It's about the same size (2 x .9 x 4.5 inches), but it's not quite as bright; it tops out at about six feet from your "screen," casting an image about 40 inches diagonally. And whereas the Optoma projector has a tiny, feeble built-in speaker, the 3M has none at all. If you plan to use it for movies, you'll also have to plan to connect headphones or speakers.
The biggest difference, though, is the intended video source. The Optoma projector is aimed almost exclusively at iPods, iPhones and other smartphones that can play video, along with video sources that have RCA cables--the red/white/yellow cable set--like camcorders, DVD players, game consoles, digital cameras and other sources.
But you can't connect it to a laptop (for spur-of-the-boardroom PowerPoint presentations, for example).
The 3M projector, on the other hand, is the only micro projector so far that accepts a standard laptop video signal (it has a VGA connector). On one hand, it may seem a little silly to use a micro projector for a laptop; in the end, the projected image isn't all THAT much larger than the laptop's own screen. Still, it can make the difference between showing your slides to three people and showing them to eight people.
The 3M also accepts input from RCA cables, just like the Optoma.
Some iPod models can use the 3M projector successfully using the Apple iPod Dock, transmitting both stills and videos. 3M says that the projector can accommodate only the still photos from an iPhone, not videos, but I couldn't get the iPhone to project anything at all. (The Optoma projects iPhone videos effortlessly--but not photos.)
The 3M's battery lasts 40 to 60 minutes, compared with 90 minutes on the Optoma.
The Aiptek PocketCinema V10 takes yet a third approach. Whereas the Optoma seems made in heaven for iPods and iPhones (and comes with the proper cable), and the 3M is a better bet for laptops, the Aiptek has a slot for a memory card, and, more intriguingly, 1 gigabyte of built-in storage.
In other words, you can carry this thing around without any other equipment at all, preloaded, ready to make your elevator pitch at any time, without having to connect or set up anything. (You do have to convert your pictures and movies to the projector's preferred formats, which can be headachey.)
Connecting a laptop is pretty much hopeless unless it has either RCA or S-Video connectors, both of which are rare on laptops these days, or a VGA-to-RCA adapter. (Once again, any video source with RCA cables will work.)
The PocketCinema ($300) is bigger than the other projectors (4.9 x 2.1 x 0.9), but it's the only one with a decent speaker, a remote and a tripod. (Maximum image and distance: 42-inch image, 5 feet away.)