Incandescent Lighting | The invention of the incandescent light bulb has a history spanning from the early 1800s. Until that time, available light sources consisted of candles, oil lanterns, and gas lamps. In 1809, an English chemist, Humphrey Davy, started the journey to the invention of a practical incandescent light source. He used a high power battery to induce current between two charcoal strips. The current flowing through the two charcoal strips produced an intense incandescent light, creating the first arc lamp.
In 1820, Warren De la Rue made the first known attempt to produce an incandescent light bulb. He enclosed a platinum coil in an evacuated tube and passed an electric current through it. The design was based on the concept that the high melting point of platinum would allow it to operate at high temperatures and that the evacuated chamber would contain less gas particles to react with the platinum, improving its longevity. Although it was an efficient design, the cost of the platinum made it impractical for commercial use.
The History of Lighting
Fluorescent Lighting | Fluorescent lighting was invented, albeit crude was invented circa 1840's. All the major features of fluorescent lighting were in place at the end of the 1920s. Decades of invention and development had provided the key components of fluorescent lamps: economically manufactured glass tubing, inert gases for filling the tubes, electrical ballasts, long-lasting electrodes, mercury vapor as a source of luminescence, effective means of producing a reliable electrical discharge, and
fluorescent coatings that could be energized
by ultraviolet light. At this point, intensive
development was more important than basic
research.
In 1934, Arthur Compton, a renowned physicist
and GE consultant, reported to the GE lamp
department on successful experiments with
fluorescent lighting at General Electric Co., Ltd.
in Great Britain (unrelated to General Electric in
the United States).
High Intensity Discharge Lighting | The basic technology for the gas-discharge lamp has existed for over 300 years, and these same principals also guided innovations in other lighting types such as fluorescent and neon.
The invention of the gas-discharge lamp is generally creditedto Francis Hauksbee, an English scientist, who first demonstrated the technology in 1705. At the time, the lamp was filled with air, but it was later discovered that the light output could be increased by filling the lamp with noble gases, such as neon, xenon, argon, or krypton. Modern HID technology has further increased light output through experimentation in gas mixtures and improved electrodes, but the functional basics of the high-intensity discharge lamp remain the same.
Induction Lighting | Nikola Tesla demonstrated wired and wireless transfer of power to electrodeless fluorescent and incandescent lamps in his lectures and articles in the 1890s, and subsequently patented a system of light and power distribution on those principles. In the lecture before the AIEE, May 20, 1891, titled Experiments with Alternating Currents of Very High Frequency and Their Application to Methods of Artificial Illumination [1] and US patent 454622, among many other references in the technical and popular press are found countless records for Tesla's priority in this field. A suit filed by Tesla against J. J. Thomson for priority on the patent was subsequently granted in Tesla's favor. As of 2011, the transcripts of the case languish in archives, awaiting processing, and eventual publishing. Noting the diagrams in Tesla's lectures and patents, a striking similarity of construction to electrodeless lamps that are available on the market currently is readily apparent. Further, a statement in 1929 by Tesla, published in The World:
"Surely, my system is more important than the incandescent lamp, which is but one of the known electric illuminating devices and admittedly not the best. Although greatly improved through chemical and metallurgical advances and skill of artisans it is still inefficient, and the glaring filament emits hurtful rays responsible for millions of bald heads and spoiled eyes. In my opinion,
it will soon be superseded by the electrodeless
vacuum tube which I brought out thirty-eight years
ago, a lamp much more economical and yielding a
light of indescribable beauty and softness."
Light Emitting Diode (LED) | Electroluminescence as a phenomenon was discovered in 1907 by the British experimenter H. J. Round of Marconi Labs, using a crystal
of silicon carbide and a cat's-whisker detector. In 1961 American experimenters Robert Biard and Gary Pittman, working at Texas Instruments, found that GaAs emitted infrared radiation when electric current was applied and received the patent for the infrared LED. The first practical visible-spectrum (red) LED was developed in 1962 by Nick Holonyak, Jr., while working at General Electric Company. Holonyak first reported this breakthrough in the journal Applied Physics Letters on the 1st December 1962. Holonyak is seen as the "father of the light-emitting diode".
A light-emitting diode (LED) is a semiconductor light source. LEDs are used as indicator lamps in many devices and are increasingly used for other lighting. Appearing as practical electronic components in 1962, early LEDs emitted low-intensity red light, but modern versions are available across the visible, ultraviolet, and infrared wavelengths, with very high brightness. When a light-emitting diode is forward-biased (switched on), electrons are able to recombine with electron holes within the device, releasing energy in the form of photons. This effect is called electroluminescence and the color of the light (corresponding to the energy of the photon) is determined by the energy gap of the semiconductor.
