Projectors have been the de facto method for displaying slideshows and other presentations to small, medium and large audiences. But projectors tend to be bulky, expensive and notoriously difficult to operate. The pico projector
seeks to put an end to all of that by packaging a full featured projector
into a device that’s about the size of a deck of cards. Traveling businesspeople around the world will rejoice once they hear about this convenient new technology. Read on to learn how pico projectors work.
Digital Light Processing (DLP) Projectors
DLP uses one small mirror for each pixel and a light source projecting onto it. The color in the picture is achieved using a color wheel in between the light source and the mirror which rotates between red, blue, and green color filters. The advantage of DLP is its size. DLP projectors can be made incredibly small, thanks to the microscopic mirrors it uses. However, some DLP projectors may create a “rainbow effect
” around the edges of the images it projects. Interestingly, the rainbow effect is actually an optical illusion that is perceived more dramatically by some people than others. Either way, the rainbow effect is mostly an issue with video and occurs less with static images, such as spreadsheets and graphs. DLP pico projectors can be powered by batteries or an AC adapter.
Liquid Crystal on Silicon (LCoS)
This technology works in a similar manner to DLP, but LCoS uses liquid crystal
matrices to filter out certain wavelengths of light. In LCoS all of the colors are delivered simultaneously from three separate chips so there is no danger of the rainbow effect, even at high resolutios. The drawbacks of an LCoS pico projector is that it typically has a lower contrast ratio than a comparable DLP pico projector and is usually a bit larger in size. LCoS does not have as high of a contrast ratio as DLP. Also, unlike DLP, LCoS can’t be made as small. Most LCoS projectors require an AC adapter for power.
Laser Beam Splitting (LBS)
This technology uses three different lasers to project each of the colors. An optic combines the three lasers into one and then a mirror guides the laser. The mirror actually targets each pixel individually and as long as a refresh rate of 60 hertz or greater is used the scanning is not noticeable. LBS uses the least power of the three. LBS pico projectors excel with their excellent color saturation, contrast and brightness and can deliver sharp images without the need for focusing and adjusting. LBS pico projectors also tend to have higher resolutions than DLP and LCoS. Of course, all of these advantages come at a price—you’ll pay much more for an LBS pico projector.
Pico projectors can be small and inexpensive with DLP, but sometimes brightness is sacrificed and rainbow effect can be a problem. LCoS can allow for a higher resolution and no worry about rainbow effect, although it can’t be as small as the other projectors. It is also a little more pricey, but gives a better brightness overall. LBS is arguably the best technology for projectors but has the highest cost. Overall, pico projectors hold much promise and are bound to improve in performance while coming down in price.