A directly addressed monolithic LED array as a projection source

Light-emitting-diode arrays have been fabricated and demonstrated by several groups in a variety of applications in which structured illumination is desired, such as direct-view displays and fluorescence detection. State-of-the-art LEDs can achieve a high optical power density, exceeding 40 W/cm(2). This allows the use of such LEDs, if patterned into an array, as a light and pattern source for projection displays. As a proof of principle, a projection source using a monolithically integrated patterned LED array at a power density of 0.69 W/cm(2), a source brightness of 21,000,000 cd/m(2), and a projected brightness of 100,000 cd/m(2) is reported. It is shown that an improved version of such a display would allow significantly better power consumption and overall system efficiency than permitted by current projection-display concepts.