LED Lamp

A LED lamp or a Light-Emitting-Diode lamp is a solid-state lamp in which a collection of light-emitting diodes serve as the source of light. Multiple diodes are employed since the individual output the light-emitting diodes are much lower than the incandescent bulbs and fluorescent lamps. Most of the LED lamps are supplied with internal circuits that help them operate from standard AC voltages. LED lamps have longer life and higher efficiency than the convention light bulbs, although the initial costs may be higher.

White light is required for general purposes. Light emitted from LEDs with very small band of wavelengths are naturally colored. The color depends on the composition of the semiconductor used. White light can be created either by mixing light from LEDs of red, green, and blue colors or by using phosphor. The former method employs multiple LED chips each of which emit a different wavelength in proximity which leads to the generation of a broad spectrum of white light. One advantage with this process is that the character of the emitted light can be adjusted controlling the intensities of the LEDs. The other method uses phosphor to convert the short wavelength of a single LED, mostly blue or ultraviolet, into white spectrum. Phosphor absorbs a part of the blue light and the residue emits in the form of a wide spectrum of white light.

LED lamps generally comprise of clusters of LEDs along with driver electronics, optics and a heat sink. To serve as a light source, a number of LEDs needs to be integrated into a lamp form to merge the illuminating effects. Arrangement of white LEDs is not essential for color balance, as is the case of color LEDs for creating equivalent brightness.

LED lamps are used both for general and special purpose lighting. LEDs offer multiple colors without any need for filters – perfect for situations requiring colored lighting. Unlike the white light source, colored LEDs do not require generating all colors and then filter a portion of the visible energy, thus improving the energy efficiency. White-light LED lamps are preferred for their long lifespan and relatively lower rate of energy consumption. The compactness of the LED sources provides flexibility in designing lighting fixtures. And good control over the distribution of light with small reflectors or lenses the light can be controlled and uniformly distributed. Vibration and shock-resistant LED lamps can produce an extensive range of colors using color-mixing principles.