| abstract |
Low profile, side-emitting LEDs (10) are described, where all light is efficiently emitted within a relatively narrow angle generally parallel to the surface of the light- generating active layer (14). The LEDs enable the creation of very thin backlights for backlighting an LCD. In one embodiment, the LED is a flip chip with the n and p electrodes (18) on the same side of the LED, and the LED is mounted electrode-side down on a submount (22). A reflector (34) is provided on the top surface of the LED so that light impinging on the reflector is reflected back toward the active layer (14) and eventually exits through a side surface of the LED. A waveguide layer (30) and/or one or more phosphors layers are deposed between the semiconductor layers (12, 14, 16) and the reflector for increasing the side emission area for increased efficiency. Side-emitting LEDs with a thickness of between 0.2-0.4 mm can be created. |