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High power light emitting diodes (LEDs) continue to increase in output flux with the best III‐nitride based devices today emitting over 150 lm of white, cyan, or green light. The key design features of such products will be covered with special emphasis on power packaging, flip‐chip device design, and phosphor coating technology. The high‐flux performance of these devices is enabling many new applications for LEDs. Two of the most interesting of these applications are LCD display backlighting and vehicle forward lighting. The advantages of LEDs over competing lighting technologies will be covered in detail.

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By using red, green, and blue (RGB) light emitting diodes (LEDs) instead of cold cathode fluorescent lamps in edge lit LCD backlights brightness and color performance (gamut) of LCD displays can be improved considerably. However: the design of an RGB-LED backlight and electronic control need special attention: the colors of the separate LEDs need to be mixed well to obtain a good spatial color uniformity while a good balance between the red, green and blue levels has to be maintained to stabilize the white point. Additional features of an RGB-LED backlight solution are: dynamic white point control (tune color point of backlight to LCD and/or displayed material), large dimming range, long lifetime, ruggedness, and the absence of mercury.

A novel LED light source, “Luxeon Direct”, has been integrated into a highly efficient direct backlight. This concept incorporates one of the latest LEDs released by Lumileds™. This direct backlight approach integrates side emitting LEDs with a highly reflective cavity placed behind the LCD. Prior to this method it has been very difficult to use high power red, green and blue (RGB) LEDs in a direct backlight design due to the high color and brightness uniformity requirements. In this paper a method will be demonstrated that can achieve excellent backlight performance using an indirect illumination approach with high power LEDs.