| 20090251882 | LIGHT-EMITTING DIODE ILLUMINATION STRUCTURES - Illumination device embodiments are provided which include a transparent bulb that carries at least one phosphor. A redirector is positioned within the bulb and at least one light-emitting diode (LED) is positioned over the redirector to be energized and emit light that excites the phosphor. The redirector helps to diffuse the resultant mix of LED-emitted light and phosphor-emitted light that issues from the device. The redirector also provides a heat path away from the LEDs. In a device embodiment, LEDS form first and second diode groups that have emission peaks in different regions. Selectively energizing these groups alters the color temperature of the device's light. Energizing both groups and varying currents of each group also alters the color temperature of the device's light. In other device embodiments, the redirector has a portion outside the bulb which may also define protuberances that enhance heat radiation. In yet other device embodiments, each LED may have an associated phosphor. Some embodiments may be further enhanced by the further addition of a phosphor to the bulb. | 10-08-2009 |
