Leds: The Light of the hereafter

Light Emitting Diodes (Leds), “semiconductors that emit light when zapped with [positive polarity] electricity,”[1] are on the verge of taking over the commercial and consumer sectors of the lighting industry. With greater efficiency, longer beneficial lives, and their “clean” nature, Leds are the future of light, pushing customary incandescent and fluorescent bulbs toward extinction. Only the higher output costs for Leds has extended the existence of customary bulbs.

History

High Intensity Flashlight

When viewing the history of customary bulbs, the higher costs linked with producing Leds is not an insurmountable hurdle to overcome. The incandescent bulb lingered for about 70 years before supplanting “candles, oil lanterns, and gas lamps” as the main source of lighting.[2] When the first crude incandescent bulb was created in 1809 by Humphrey Davy, an English chemist, using two charcoal strips to furnish light, it remained impractical. Later when the first true incandescent bulb was created by Warren De la Rue in 1820, utilizing a platinum filament to furnish light, it was too high-priced for commercial use. Only when Thomas Edison created an incandescent bulb utilizing a carbonized filament within a vacuum in 1879, did the incandescent bulb become practical and affordable for consumer use.

Leds: The Light of the hereafter

Although considered relatively novel, the opinion for Leds first arose in 1907 when Henry Joseph Round used a piece of Silicone Carbide (SiC) to emit a dim, yellow light. This was followed by experiments conducted by Bernhard Gudden and Robert Wichard Pohl in Germany during the late 1920s, in which they used “phosphor materials made from Zinc Sulphide (ZnS) [treated] with Copper (Cu)” to furnish dim light.[3] However, during this time, a major obstacle existed, in that many of these early Leds could not function efficiently at room temperature. Instead, they needed to be submerged in liquid nitrogen (N) for optimal performance.

This led to British and American experiments in the 1950s that used Gallium Arsenide (GaAs) as a substitute for Zinc Sulphide (ZnS) and the creation of an Led that produced invisible, infrared light at room temperature. These Leds immediately found use in photoelectric, sensing applications. The first “visible spectrum” Led, producing “red” light was created in 1962 by Nick Holonyak, Jr. (b. 1928) of the general electric enterprise who used Gallium Arsenide Phosphide (GaAsP) in place of Gallium Arsenide (GaAs). Once in existence, they were quickly adopted for use as indicator lights.

Before long these red Leds were producing brighter light and even orange-colored electroluminescence when Gallium Phosphide (GaP) substrates were used. By the mid 1970s, Gallium Phoshide (GaP) itself along with dual Gallium Phosphide (GaP) substrates were being used to furnish red, green, and yellow light. This ushered in the trend “towards [Led use in] more practical applications” such as calculators, digital watches and test equipment, since these vast colors addressed the fact that “the human eye is most responsive to yellow-green light.”[4]

However, rapid growth in the Led industry did not begin until the 1980s when Gallium Aluminium Arsenides (GaAias) were developed, providing “superbright” Leds (10x brighter than Leds in use at the time) – “first in red, then yellow and… green,” which also required less voltage providing energy savings. [5] This led to the opinion of the first Led flashlight, in 1984.

Then in parallel with emerging laser diode technology, which focused on maximizing light output, the first “ultrabright” Leds were created in the early 1990s through the use of Indium Gallium Aluminium Phosphide (InGaAip) led in part by Toshiba’s creation of an Led that “reflected 90% or more of the generated light…” In addition, during this same period, it was discovered that separate colors, including “white” (although a “true” white light was only recently produced through the use of an organic Led (Oled) by Cambridge Display Technology, in the U.K.) could be produced through “adjustments in the size of the energy band gap” when Indium Gallium Aluminium Phosphide (InGaAip) was used, much in part because of the work of Shuji Nakamura of Nichia Corporation, who industrialized the world’s first blue Led in 1993.[6] Today, this technology is used to furnish Leds that even emit “exotic colors” such as pink, purple and aqua as well as “genuine ultra-violet ‘black’ light.[7]

A vital milestone was reached in 1997 when it became cost efficient to furnish “high brightness” Leds in which the intensity (benefits) exceeded the linked costs to furnish it.
In conjunction with this milestone, newer technology is emerging that will likely reduce costs even further (and improve lighting) – the introduction of measure dots or puny crystals ([8]

Advantages

The advantages of adopting Leds to supply sole source lighting for every application are significant. Leds emit virtually no heat (wasted energy) and are “in fact… cool to the touch” unlike incandescent light bulbs. They are also more durable (encased in a hardened shell and defiant to vibration and shocks) than and last up to 50 times longer than customary incandescent and fluorescent bulbs ( some can be used for up to 10 years), and they “use a greater proportion of the electricity flowing through them” translating into “savings for consumers.” [9] agreeing to the U.S. Division of Energy, “widespread adoption of Leds could cut U.S. consumption of electricity for lighting by 29%”[10] since they wish less energy to function and by their nature, reduce the estimate of air conditioning needed to keep areas cool and comfortable.

The shape of Leds also provides lighting benefits when compared to that of customary bulbs. Unlike incandescent and fluorescent bulbs, Leds do not wish the use of an external reflector to procure and direct their light. In addition, “Leds light up very quickly… achiev[ing] full glow in approximately 0.01 seconds – 10 times faster than” customary bulbs.[11]

Leds also furnish no ultra-violet output, which can damage fabrics, unlike customary bulbs; they are light-weight, ecologically friendly, and can furnish separate colors (without the use of color filters) based on the estimate of power provided to each customary color ensuring that electricity is not wasted. The Massachusetts produce of Technology (Nano Structures Lab) is presently conducting explore that could lead to the creation of an Led “where both color and intensity (brightness) can be set electronically.”[12]

Uses and the Future

As Leds gain a greater measure of the lighting market, they are currently used in a range of devices and applications fluctuating from traffic control devices (e.g. Traffic lights, which comprise the single signal expedient that changes colors from green to yellow to red), barrier lights, hazard signs, message displays (e.g. Times Square, New York, commodities and news message boards, scoreboards), cellphones, televisions, large video screens used at sporting and other outdoor events (e.g. Miami Dolphins end-zone screen), calculators, digital clocks and watches, flashlights (including models for which 60 seconds of by hand winding provides one-hour of light, eliminating the need to stockpile fresh batteries for emergencies), Christmas lights, airport runway lights, buoy lights, and automotive applications (e.g. Indicator lights as well as head lights and signal lights in some vehicles; driver’s of the new 2006 Ford Mustang can even convert the color (125 separate varieties) of their “Led-laden dashboard by using the ‘MyColor’ feature”[13]).

In fact the automotive industry plans to replace all bulbs with Leds by 2010, while efforts are currently underway to replace all traffic signals with Led devices. At the same time, plans are in place to at last use Leds to light streets as well as much of the Third World and other areas “with no means of electricity” since “solar expensed batteries” can power Leds for the period of each night. [14]

In addition, “Phillips Electronics is developing remote-controlled Led room lighting [while] Boeing Corp. Plans to use Led’s throughout the interior of its new 787 Dreamliner commercial jet.”[15]

With the promise that Leds hold, it is likely that someday they will supply illumination for houses and offices, X-Ray capabilities for the medical field, power computer monitors, as well as an assortment of other devices and applications. The possibilities are endless. However, before Leds can supplant the customary bulb, “designers and advocates of the technology must overcome… the usual obstacles to mainstream shop adoption: Industry-accepted standards must be industrialized and costs must be reduced.”[16] Currently costs are coming down and some clubs are absorbing towards these industry standards (e.g. Phillips Electronics is working on Led bulbs that can screw into existing light sockets, while besthomeledlighting.com already offers Led screwable bulbs -- one consisting of 70 Leds that emits a "warm white color similar to the light from an incandescent bulb"[17] using only 3 Watts of energy and an additional one Led bulb that indubitably changes colors when lit). With these efforts along with the adoption, exploitation, and output of Led technology by growing numbers of companies, it is determined that Leds will become the sole source of lighting rendering customary incandescent and fluorescent bulbs extinct. In short, Leds are the light of the future, a light that will benefit not only consumers but also industry and the Earth in general.
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[1]Evan Ramstad and Kathryn Kranshold. Changing the Light Bulb. The Wall road Journal. June 8, 2006. B1.

[2]The History of the Light Bulb. 9 June 2006. http://invsee.asu.edu/Modules/lightbulb/meathist.htm

[3]A brief history of the Light Emitting Diode (Led). Wavicle Ltd. 2002-2006. 9 June 2006. http://www.wavicle.biz/led_history.html

[4]The History of Led Technology. Marktech Optoelectronics. 2006. 8 June 2006. [http://www.marktechopto.com/Engineering%20Services/leds-drivers-displays-driver-technical-]
articles-detailed/leds-drivers-displays-driver-technical-articles-history.cfm

[5]A brief history of the Light Emitting Diode (Led). Wavicle Ltd. 2002-2006. 9 June 2006. http://www.wavicle.biz/led_history.html

[6]The History of Led Technology. Marktech Optoelectronics. 2006. 8 June 2006. [http://www.marktechopto.com/Engineering%20Services/leds-drivers-displays-driver-technical-]
articles-detailed/leds-drivers-displays-driver-technical-articles-history.cfm

[7]A brief history of the Light Emitting Diode (Led). Wavicle Ltd. 2002-2006. 9 June 2006. http://www.wavicle.biz/led_history.html

[8] Joab Jackson. Accidental Find to Signal “Lights Out” for Incandescent Bulbs? National Geographic.com. 1 November 2005. 9 June 2006. http://news.nationalgeographic.com/news/2005/11/1101_051101_quantum_lightbulb.html

[9]Joab Jackson. Accidental Find to Signal “Lights Out” for Incandescent Bulbs? National Geographic.com. 1 November 2005. 9 June 2006. http://news.nationalgeographic.com/news/2005/11/1101_051101_quantum_lightbulb_2.html

[10]Joab Jackson. Accidental Find to Signal “Lights Out” for Incandescent Bulbs? National Geographic.com. 1 November 2005. 9 June 2006. http://news.nationalgeographic.com/news/2005/11/1101_051101_quantum_lightbulb_2.html

[11]Light-emitting diode. Wikipedia.com. 2006. 9 June 2006. http://en.wikipedia.org/wiki/Leds

[12]A brief history of Led lighting. 9 June 2006. [http://216.239.51.104/search?q=cache:ach2mPa9iP0J:www.artisticlicence.com/]
app%2520notes/appnote022.pdf+A+Brief+History+of+Led+Lighting&hl=en&gl=us&ct=clnk&cd=3

[13]Evan Ramstad and Kathryn Kranshold. Changing the Light Bulb. The Wall road Journal. June 8, 2006. B6.

[14]A brief history of the Light Emitting Diode (Led). Wavicle Ltd. 2002-2006. 9 June 2006. http://www.wavicle.biz/led_history.html

[15]Evan Ramstad and Kathryn Kranshold. Changing the Light Bulb. The Wall road Journal. June 8, 2006. B6.

[16]Joe Knisley. Understanding Led Technology. Ec&M. 1 April 2002. 8 June 2006. http://www.ecmweb.com/mag/electric_understanding_led_technology/

[17]70-Led Light Bulb, White Large Globe. 10 June 2006. [http://www.besthomeledlighting.com/product/G32-120-E27-70-W]
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Sources:

A brief history of Led lighting. 9 June 2006. [http://216.239.51.104/search?q=cache:ach2mPa9iP0J:www.artisticlicence.com/app%2520notes/appnote022.pdf]
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A brief history of the Light Emitting Diode (Led). Wavicle Ltd. 2002-2006. 9 June 2006. http://www.wavicle.biz/led_history.html

Cameron Walker. Green Christmas: Tips for an Eco-Friendly Holiday.Changing the Light Bulb. The Wall road Journal. June 8, 2006.

Joab Jackson. Accidental Find to Signal “Lights Out” for Incandescent Bulbs? National Geographic.com. 1 November 2005. 9 June 2006. http://news.nationalgeographic.com/news/2005/11/1101_051101_quantum_lightbulb.html

Joe Knisley. Understanding Led Technology. Ec&M. 1 April 2002. 8 June 2006. http://www.ecmweb.com/mag/electric_understanding_led_technology/

Led Light Bulbs. 10 June 2006. http://www.besthomeledlighting.com/all_led_bulbs?gclid=CnmA2KkdvYucft1qGgodRqn7qA

Light-emitting diode. Wikipedia.com. 2006. 9 June 2006. http://en.wikipedia.org/wiki/Leds

Mary Bellis. The Inventions of Thomas Edison. About, Inc. A Part of The New York Times Company. 2006. 9 June 2006. http://inventors.about.com/library/inventors/bledison.htm

The History of Led Technology. Marktech Optoelectronics. 2006. 8 June 2006. [http://www.marktechopto.com/Engineering%20Services/leds-drivers-displays-driver-]
technical-articles-detailed/leds-drivers-displays-driver-technical-articles-history.cfm

The History of the Light Bulb. 9 June 2006. http://invsee.asu.edu/Modules/lightbulb/meathist.htm

Leds: The Light of the hereafter

Consumer's Guide To Four beloved Self-Defense Products

Self-defense products have in case,granted a nonlethal alternative to deadly force since man was created. The right to self-defense has been nearby forever. Yes man has created deadly ways to defend himself but many people like a nonlethal alternative for personal security and personal safety. Sticks and stones were nearby a lot earlier than handguns.

If you trace the history of pepper spray, for example, the origins go back thousands of years. Even the history of stun devices is hundreds of years old. Tasers, on the other hand, are relatively new. In this record we will retell four beloved self-defense products and discuss their pros and cons so you can make an informed decision as to which one you might want to have.

High Intensity Flashlight

Pepper Spray

Consumer's Guide To Four beloved Self-Defense Products

We'll start with the most widely used nonlethal product for self defense-pepper sprays. They use the resin of a very hot pepper as the basis for the main ingredient, oleoresin capsicum. The usual attentiveness is 10%, but some manufacturers use as much as 18% concentration. The main way that defensive sprays are judged is in the part of hotness or Scoville heat units or Shu's.

Most have Scoville heat units in the 2 million range. Wildfire brand claims to have 3 million Scoville heat units. The type of pepper spray used by a lot of police agencies is the Fox brand and it has 5.3 million Shu's production it the hottest in the marketplace. A haberno pepper, one of the hottest in the world, by comparison, has practically 200,000 Shu's.

What makes pepper spray so productive as a self-defense item for personal security and personal safety, is the fact that it can disable an assailant for up to 45 minutes by creating, first of all intense pain, then tearing of the eyes so badly that they may end up shutting. Then there's difficulty breathing, coughing and choking. These symptoms go away at last but if you can't see and you can't breathe, assaulting someone becomes problematic.

Law promulgation agencies and forces units have used pepper sprays for decades for crowd control and criminal apprehension. They are widely recognized as one of the most productive deterrents against dog attacks and bear attacks. The Usps started issuing pepper sprays to their letter carriers over 30 years ago to defend against dog attacks. The Fbi started using pepper sprays for their Swat teams in the 1990s.

Most pepper sprays have a range of 6 to 12 feet. Pepper gels, because they hold up good in wind conditions, have a longer range of up to 18 to 20 feet. The Mace pepper gun has a range of up to 25 feet. Some bear pepper sprays have a range up to 30 feet.

The main negative of pepper sprays is that when they are used outside they are field to wind conditions and even a 10 mile an hour wind can blow a spray off course. Pepper sprays come in distinct disbursement methods, the most coarse being a spray. But there is also a gel, foam and a pepper ball which shoots out of a gun. Some police agencies such as Swat teams even have pepper grenades that they use for extra situations.

Defensive sprays can be disguised as distinct products. The most coarse of which is a lipstick dispenser, but there is also a beloved perfume dispenser that has a pepper spray inside.

They are an inexpensive and productive first-line defense for civilians' personal security and personal safety. Pepper sprays can range in price from as limited as .95 up to for a bear pepper spray. Pepper sprays are, on average, close to 90% effective. Some cities and states have restrictions on pepper sprays

Stun Devices

Stun devices were first created shortly after the battery was patented. Farmers developed the cattle prod to move their cattle along without harming them. It was only a matter of time before the forces and law promulgation saw the possible as a nonlethal way to control suspects.

Stun devices use an electrical charge that comes from probes on one end of the device. The electricity from the charge causes the muscles to over work very rapidly depleting the body of all blood sugars that are needed for energy. Stun devices use high voltage and low amperage to disable an assailant for up to 10 minutes. The electrical charge also disrupts neurological impulses that control muscle movement causing the assailant to lose his balance.

Stun devices vary in price from nearby up to as high as depending on the voltage and the features. They are, on average, close to 90% effective. Some cities and states have restrictions on stun
devices. A disadvantage to a stun gadget that many don't like is the fact that ist has to be physically applied to an assailant.

Another type of stun gadget is the taser. It is used by well over 12,000 law promulgation agencies in the United States and in at least eight foreign countries. It is nearly 100% productive with more stopping power than a 9 mm handgun. Civilian models can stop an assailant up to 15 feet away Tasers use low voltage and high amperage to override the central nervous system. Tasers start at 0 and need a police background check before the product can be activated.

Panic Alarms

Panic alarms, or personal alarms as some call them, are small hand-held devices that emit a loud sound when activated. They are inexpensive and very productive at drawing attentiveness to your situation and have the possible of scaring an assailant away because of the loud noise. The 120 db Keychain Panic Alarm is a great example of one. Some panic alarms are five dollars or less.

Batons

Batons are used by law promulgation officers for criminal apprehension purposes. In the hands of a trained professional a baton can be a very productive self-defense tool. The most coarse type ready for civilians is the telescoping or expandable steel baton that goes from as limited as 8 inches up to as much as 26 inches. A well-placed attack with a steel baton can break bones or as at absolute minimum impose a great deal of pain. A steel baton can cost in the neighborhood of -.

When it comes to self-defense products for personal security and personal security, consumers have many choices. These are four of the most coarse and beloved products used for nonlethal self-defense.

Consumer's Guide To Four beloved Self-Defense Products