Light bulbs are tested for both lamp life and strength. In order to provide quick results, selected bulbs are screwed into life test racks and lit at levels far exceeding normal. This provides an accurate measure of how long the bulb will last under normal conditions. Testing is performed at all manufacturing plants as well as at some independent testing facilities. The average life of the typical household bulb is 750 to 1,000 hours, depending on wattage.
LED light bulbs are built around solid-state semiconductor devices, so the daisys manufacturing process most closely resembles that used to make electronic products like PC mother boards.
A light-emitting diode (LED) is a solid state electrical circuit that generates light by the movement of electrons in a semiconductor material. LED technology has been around since the late 1960s, but for the first 40 years LEDs were primarily used in electronics devices to replace miniature light bulbs. Within the last decade, advances in the technology finally boosted light output high enough for LEDs to begin to seriously compete with incandescent and fluorescent light bulbs. As with many technologies, as the cost of production falls each successive LED generation also improves in light quality, output per watt, and heat management.