Having recently covered the Edison Menlo Park Museum Light Bulb Memorial
("You Buy its little Brother for a Dime"), a natural follow on is a look at the Edison Tech Center in Schenectady, New York...
The Edison Tech Center is a unique multi-department, dynamic, hands-on workshop that turns the technological revolution into an experience and transforms the historic giants of technology into "virtual" teachers and motivators. Our facility provides access to samples of technology spanning over 130 years. Participants of all ages can see how things work, and learn about the engineering pioneers who helped improve our world.
From an extensive website system, taking lighting alone, a menu page leads on to separate sites for all sorts of lighting, their development, how they work, and their advantages and disadvantages:
incandescents, arc lamps, fluorescents, LEDs and more...
In turn then, a good presentation of íncandescent lighting through the ages, with photographs, videos, documents...
Bamboo is good for pandas... and light bulbs!
Joseph Swan and Thomas Edison independently hit success by making a bulb that would last a reasonable number of hours.
Swan used carbonized paper to create his early filaments.
Edison first used carbonized sewing thread as a filament, he managed to get it inside a vacuum. This made his first practical lightbulb. He used carbonized sewing threads until 1880. Then he used paper bristol board. (Carbonized paper) This move increased lamp life to 600 hours.
Bamboo brings great improvements:
1883: As the story goes Edison was using a fan on a hot day, he unwound fine bamboo on a fold-out oriental fan. He carbonized it and tested it as a filament. He send assistants to Japan to find the type of bamboo that was used in that fan. They found it and imported the filaments.
The first bamboo filaments had a square shape because they were cut from larger pieces using a certain process. He electroplated the bamboo directly to the lead in wires to avoid the high cost of platinum clamps. Later he used carbon paste to adhere the bamboo to the lead in wires.
Edison continued to use bamboo filaments until the creation of General Electric in 1892...
Halogen incandescents have their own site...
The halogen lamp has a tungsten filament similar to the standard incandescent lamp, however the lamp is much smaller for the same wattage, and contains a halogen gas in the bulb. The halogen is important in that is stops the blackening and slows the thinning of the tungsten filament. This lengthens the life of the bulb and allows the tungsten to safely reach higher temperatures (therefore makes more light). The bulb must be able to stand higher temperatures so fused quartz is often used instead of normal silica glass.
Not forgetting flashbulbs...
The traditional flashbulb is another type of incandescent lightbulb. Early flash bulbs used a aluminum, zirconium, or magnesium filament or aluminum foil. Current was passed through the material and it glowed. The melting and boiling point of aluminum, magnesium or zirconium is so low that the lamp would vaporize the metal, which further intensified the brightness. Early lamps would last one flash and had to be replaced. Early flashbulbs often had an Edison type screw in thread like a regular lightbulb. Later lamps could last a few flashes. Later on disposable flash bulb arrays were developed to allow many flashes without switching bulbs.
Modern flashbulbs found on most cameras are no longer incandescent bulbs. They are tiny xenon arc tubes. An electric arc is formed through xenon gas. These have the great advantage of being reusable. They have the disadvantage of being a shorter duration than incandescent flash bulbs. This means they have to be more precisely timed.
Finishing with a threatening but perhaps also hopeful note...
The future of incandescent lamps:
The Incandescent lamp has been in the average household for more than 120 years. In the last decade a major initiative to develop more (energy) efficient lightbulbs has replaced much of the world's bulbs with compact fluorescents.
There has been significant resistance to bans on the incandescent bulb...
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