Little Screen, Big Picture
Cell phones and personal digital assistants get smaller each year, but greater portability comes at a price. The devices’ shrunken screens make information hard to read-and even harder to share with others. V. Michael Bove Jr. and Wilfrido Sierra at MIT’s Media Lab are developing a miniature laser projector to make handheld devices easier on the eyes. The projector consists of an array of semiconductor lasers spaced micrometers apart, approximately one laser per pixel. A tiny mirror mounted above the array rotates to sweep the beams up and down while their intensities are varied, reproducing text and simple images. With the touch of a button, a cell phone could project its postage-stamp-sized display as an image up to a meter diagonal on a conference room wall. The compact, low-power lasers won’t take up much room and won’t squander battery life. Bove expects the projectors to appear in phones in two to five years.