One-hundred-and-thirty years ago, Thomas Edison completed the first successful sustained test of the incandescent light bulb. With some incremental improvements along the way, Edison's basic technology has lit the world ever since. This is about to change. We are on the cusp of a semiconductor-based lighting revolution that will ultimately replace Edison's bulbs with a far more energy-efficient lighting solution. Solid state LED lighting will eventually replace almost all of the hundreds of billions of incandescent and fluorescent lights in use around the world today. In fact, as a step along this path, President Obama last June unveiled new, stricter lighting standards that will support the phasing out of incandescent bulbs (which already are banned in parts of Europe).
To understand just how revolutionary LED light bulbs are as well as why they are still expensive, it is instructive to look at how they are manufactured and to compare this to the manufacture of incandescent light bulbs. This article explores how incandescent light bulbs are made and then contrasts that process with a description of the typical manufacturing process for LED light bulbs.
So, let's begin by taking a look at how traditional incandescent light bulbs are manufactured. You will find that this is a classic example of an automated industrial process refined in over a century of experience.
While individual incandescent light bulb types differ in size and wattage, all of them have the three basic parts: the filament, the bulb, and the base. The filament is made of tungsten. While very fragile, tungsten filaments can withstand temperatures of 4,500 degrees Fahrenheit and above.
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USB Plug Clip-on 3 LED Light Lamp for Laptop