id stringlengths 24 24 | question stringlengths 1 270 | answer stringlengths 1 239 | documents listlengths 1 1 |
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57314c7c05b4da19006bcffe | Who was appointed to the Chief of Staff of the Air Force following Mosley's resignation? | General Norton A. Schwartz | [
"United_States_Air_Force\n\nIn response to the 2007 United States Air Force nuclear weapons incident, Secretary of Defense Robert Gates accepted in June 2009 the resignations of Secretary of the Air Force Michael Wynne and the Chief of Staff of the Air Force General T. Michael Moseley. Moseley's successor, General ... |
57314c7c05b4da19006bcfff | What newspaper reported on Schwartz's dismantlement of the US Air Force's class system? | The Washington Post | [
"United_States_Air_Force\n\nIn response to the 2007 United States Air Force nuclear weapons incident, Secretary of Defense Robert Gates accepted in June 2009 the resignations of Secretary of the Air Force Michael Wynne and the Chief of Staff of the Air Force General T. Michael Moseley. Moseley's successor, General ... |
57314e60a5e9cc1400cdbe49 | What author wrote about the US Air Force egalitarian culture? | Major General Charles J. Dunlap, Jr. | [
"United_States_Air_Force\n\nDaniel L. Magruder, Jr defines USAF culture as a combination of the rigorous application of advanced technology, individualism and progressive airpower theory. Major General Charles J. Dunlap, Jr. adds that the U.S. Air Force's culture also includes an egalitarianism bred from officers p... |
57314e60a5e9cc1400cdbe4a | How does the US Air Force differ from other branches of the military? | an organization in which mostly its officers fought | [
"United_States_Air_Force\n\nDaniel L. Magruder, Jr defines USAF culture as a combination of the rigorous application of advanced technology, individualism and progressive airpower theory. Major General Charles J. Dunlap, Jr. adds that the U.S. Air Force's culture also includes an egalitarianism bred from officers p... |
57314e60a5e9cc1400cdbe4b | How have the enlisted forces of the US Air Force been seen? | primarily a rear echelon support force | [
"United_States_Air_Force\n\nDaniel L. Magruder, Jr defines USAF culture as a combination of the rigorous application of advanced technology, individualism and progressive airpower theory. Major General Charles J. Dunlap, Jr. adds that the U.S. Air Force's culture also includes an egalitarianism bred from officers p... |
57314fe6497a881900248db7 | What is the reason for the shortage of UAV operators in the US Air Force? | Cultural and career issues | [
"United_States_Air_Force\n\nCultural and career issues in the U.S. Air Force have been cited as one of the reasons for the shortfall in needed UAV operators. In spite of an urgent need for UAVs or drones to provide round the clock coverage for American troops during the Iraq War, the USAF did not establish a new ca... |
57314fe6497a881900248db8 | During what war the the USAF establish a new career field for piloting UAVs and drones? | Iraq War | [
"United_States_Air_Force\n\nCultural and career issues in the U.S. Air Force have been cited as one of the reasons for the shortfall in needed UAV operators. In spite of an urgent need for UAVs or drones to provide round the clock coverage for American troops during the Iraq War, the USAF did not establish a new ca... |
57314fe6497a881900248db9 | Why did the USAF change its training methods on UAVs in 2014? | large aircraft losses in training | [
"United_States_Air_Force\n\nCultural and career issues in the U.S. Air Force have been cited as one of the reasons for the shortfall in needed UAV operators. In spite of an urgent need for UAVs or drones to provide round the clock coverage for American troops during the Iraq War, the USAF did not establish a new ca... |
57314fe6497a881900248dba | What branch of the US Military does a cultural divide prevent the US Air Force from adopting their drone protocols? | US Army | [
"United_States_Air_Force\n\nCultural and career issues in the U.S. Air Force have been cited as one of the reasons for the shortfall in needed UAV operators. In spite of an urgent need for UAVs or drones to provide round the clock coverage for American troops during the Iraq War, the USAF did not establish a new ca... |
573156ffe6313a140071ce3a | Where did some of the US Air Force traditions come from? | Royal Air Force | [
"United_States_Air_Force\n\nMany of the U.S. Air Force's formal and informal traditions are an amalgamation of those taken from the Royal Air Force (e.g., dining-ins/mess nights) or the experiences of its predecessor organizations such as the U.S. Army Air Service, U.S. Army Air Corps and the U.S. Army Air Forces. ... |
573156ffe6313a140071ce3b | What traditions does the US Air Force have? | "Friday Name Tags" in flying units | [
"United_States_Air_Force\n\nMany of the U.S. Air Force's formal and informal traditions are an amalgamation of those taken from the Royal Air Force (e.g., dining-ins/mess nights) or the experiences of its predecessor organizations such as the U.S. Army Air Service, U.S. Army Air Corps and the U.S. Army Air Forces. ... |
573156ffe6313a140071ce3c | What organization did the US Air Force adopt "Challenge Coins" from? | U.S. Army | [
"United_States_Air_Force\n\nMany of the U.S. Air Force's formal and informal traditions are an amalgamation of those taken from the Royal Air Force (e.g., dining-ins/mess nights) or the experiences of its predecessor organizations such as the U.S. Army Air Service, U.S. Army Air Corps and the U.S. Army Air Forces. ... |
573156ffe6313a140071ce3d | What does the roof stomp tradition signify in the US Air Force? | welcome a new commander or to commemorate another event, such as a retirement | [
"United_States_Air_Force\n\nMany of the U.S. Air Force's formal and informal traditions are an amalgamation of those taken from the Royal Air Force (e.g., dining-ins/mess nights) or the experiences of its predecessor organizations such as the U.S. Army Air Service, U.S. Army Air Corps and the U.S. Army Air Forces. ... |
573158b9e6313a140071ce56 | What was a recent US Air Force recruiting slogan? | "No One Comes Close" | [
"United_States_Air_Force\n\nThe United States Air Force has had numerous recruiting slogans including \"No One Comes Close\" and Uno Ab Alto (\"One From On High\"). For many years, the U.S. Air Force used \"Aim High\" as its recruiting slogan; more recently, they have used \"Cross into the Blue\", \"We've been wait... |
573158b9e6313a140071ce57 | What does the USAF slogan Uno Ab Alto mean? | "One From On High" | [
"United_States_Air_Force\n\nThe United States Air Force has had numerous recruiting slogans including \"No One Comes Close\" and Uno Ab Alto (\"One From On High\"). For many years, the U.S. Air Force used \"Aim High\" as its recruiting slogan; more recently, they have used \"Cross into the Blue\", \"We've been wait... |
573158b9e6313a140071ce58 | What is the most recent US Air Force recruitment slogan in October 2010? | "Aim high" followed with the response, "Fly-Fight-Win" | [
"United_States_Air_Force\n\nThe United States Air Force has had numerous recruiting slogans including \"No One Comes Close\" and Uno Ab Alto (\"One From On High\"). For many years, the U.S. Air Force used \"Aim High\" as its recruiting slogan; more recently, they have used \"Cross into the Blue\", \"We've been wait... |
573158b9e6313a140071ce59 | Where can individual each USAF wing, group or squadrons individual motto be found? | wing, group, or squadron websites | [
"United_States_Air_Force\n\nThe United States Air Force has had numerous recruiting slogans including \"No One Comes Close\" and Uno Ab Alto (\"One From On High\"). For many years, the U.S. Air Force used \"Aim High\" as its recruiting slogan; more recently, they have used \"Cross into the Blue\", \"We've been wait... |
5730c0c0396df9190009631e | What type of atmosphere can LED lighting be used? | environmental | [
"Light-emitting_diode\n\nRecent developments in LEDs permit them to be used in environmental and task lighting. LEDs have many advantages over incandescent light sources including lower energy consumption, longer lifetime, improved physical robustness, smaller size, and faster switching. Light-emitting diodes are n... |
5730c0c0396df9190009631f | What is an advantage to using LED lighting over the normal light sources? | longer lifetime | [
"Light-emitting_diode\n\nRecent developments in LEDs permit them to be used in environmental and task lighting. LEDs have many advantages over incandescent light sources including lower energy consumption, longer lifetime, improved physical robustness, smaller size, and faster switching. Light-emitting diodes are n... |
5730c0c0396df91900096320 | What does LED stand for? | Light-emitting diodes | [
"Light-emitting_diode\n\nRecent developments in LEDs permit them to be used in environmental and task lighting. LEDs have many advantages over incandescent light sources including lower energy consumption, longer lifetime, improved physical robustness, smaller size, and faster switching. Light-emitting diodes are n... |
5730c0c0396df91900096321 | Why are some people hesitant to use LED lighting? | more expensive | [
"Light-emitting_diode\n\nRecent developments in LEDs permit them to be used in environmental and task lighting. LEDs have many advantages over incandescent light sources including lower energy consumption, longer lifetime, improved physical robustness, smaller size, and faster switching. Light-emitting diodes are n... |
5730c0c0396df91900096322 | What is a popular use for LED lighting? | traffic signals | [
"Light-emitting_diode\n\nRecent developments in LEDs permit them to be used in environmental and task lighting. LEDs have many advantages over incandescent light sources including lower energy consumption, longer lifetime, improved physical robustness, smaller size, and faster switching. Light-emitting diodes are n... |
5730c1d7069b531400832311 | LED lighting is the end result of what phenomenon? | Electroluminescence | [
"Light-emitting_diode\n\nElectroluminescence 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. Soviet inventor Oleg Losev reported creation of the first LED in 1927. His research was distributed in Soviet,... |
5730c1d7069b531400832312 | When was Electroluminescence discovered? | 1907 | [
"Light-emitting_diode\n\nElectroluminescence 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. Soviet inventor Oleg Losev reported creation of the first LED in 1927. His research was distributed in Soviet,... |
5730c1d7069b531400832313 | What was the nationality of the man who discovered Electroluminescence? | British | [
"Light-emitting_diode\n\nElectroluminescence 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. Soviet inventor Oleg Losev reported creation of the first LED in 1927. His research was distributed in Soviet,... |
5730c1d7069b531400832314 | What type of detector did H.J. Round use to help him in his discovery? | cat's-whisker | [
"Light-emitting_diode\n\nElectroluminescence 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. Soviet inventor Oleg Losev reported creation of the first LED in 1927. His research was distributed in Soviet,... |
5730c1d7069b531400832315 | Who is the Soviet man that created the first LED? | Oleg Losev | [
"Light-emitting_diode\n\nElectroluminescence 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. Soviet inventor Oleg Losev reported creation of the first LED in 1927. His research was distributed in Soviet,... |
5730c3e8f6cb411900e24474 | What year was it discovered that early LED instruments could be used for non-radio communication? | 1957 | [
"Light-emitting_diode\n\nIn 1957, Braunstein further demonstrated that the rudimentary devices could be used for non-radio communication across a short distance. As noted by Kroemer Braunstein\".. had set up a simple optical communications link: Music emerging from a record player was used via suitable electronics ... |
5730c3e8f6cb411900e24475 | Who discovered non-radio uses for early LED devices? | Kroemer Braunstein | [
"Light-emitting_diode\n\nIn 1957, Braunstein further demonstrated that the rudimentary devices could be used for non-radio communication across a short distance. As noted by Kroemer Braunstein\".. had set up a simple optical communications link: Music emerging from a record player was used via suitable electronics ... |
5730c3e8f6cb411900e24476 | The current in non-radio communication had to go through what type of component? | a GaAs diode | [
"Light-emitting_diode\n\nIn 1957, Braunstein further demonstrated that the rudimentary devices could be used for non-radio communication across a short distance. As noted by Kroemer Braunstein\".. had set up a simple optical communications link: Music emerging from a record player was used via suitable electronics ... |
5730c3e8f6cb411900e24477 | What other component was needed to detect the first current of a non-radio signal? | a PbS diode | [
"Light-emitting_diode\n\nIn 1957, Braunstein further demonstrated that the rudimentary devices could be used for non-radio communication across a short distance. As noted by Kroemer Braunstein\".. had set up a simple optical communications link: Music emerging from a record player was used via suitable electronics ... |
5730c3e8f6cb411900e24478 | What final device was needed to hear the signal from the initial GaAs diode? | audio amplifier | [
"Light-emitting_diode\n\nIn 1957, Braunstein further demonstrated that the rudimentary devices could be used for non-radio communication across a short distance. As noted by Kroemer Braunstein\".. had set up a simple optical communications link: Music emerging from a record player was used via suitable electronics ... |
5730c541f6cb411900e2447e | In what state what near-infrared light emission discovered? | Texas | [
"Light-emitting_diode\n\nIn September 1961, while working at Texas Instruments in Dallas, Texas, James R. Biard and Gary Pittman discovered near-infrared (900 nm) light emission from a tunnel diode they had constructed on a GaAs substrate. By October 1961, they had demonstrated efficient light emission and signal c... |
5730c541f6cb411900e2447f | What type of diode was used to help discover near-infrared light emission? | tunnel | [
"Light-emitting_diode\n\nIn September 1961, while working at Texas Instruments in Dallas, Texas, James R. Biard and Gary Pittman discovered near-infrared (900 nm) light emission from a tunnel diode they had constructed on a GaAs substrate. By October 1961, they had demonstrated efficient light emission and signal c... |
5730c541f6cb411900e24480 | In what year was the patent filed for the Semiconductor Radiant Diode? | 1962 | [
"Light-emitting_diode\n\nIn September 1961, while working at Texas Instruments in Dallas, Texas, James R. Biard and Gary Pittman discovered near-infrared (900 nm) light emission from a tunnel diode they had constructed on a GaAs substrate. By October 1961, they had demonstrated efficient light emission and signal c... |
5730c541f6cb411900e24481 | What was the first practical LED? | GaAs infrared (IR) light-emitting diode | [
"Light-emitting_diode\n\nIn September 1961, while working at Texas Instruments in Dallas, Texas, James R. Biard and Gary Pittman discovered near-infrared (900 nm) light emission from a tunnel diode they had constructed on a GaAs substrate. By October 1961, they had demonstrated efficient light emission and signal c... |
5730c541f6cb411900e24482 | The two inventors of the first practical diode were employed by what famous company? | Texas Instruments (TI) | [
"Light-emitting_diode\n\nIn September 1961, while working at Texas Instruments in Dallas, Texas, James R. Biard and Gary Pittman discovered near-infrared (900 nm) light emission from a tunnel diode they had constructed on a GaAs substrate. By October 1961, they had demonstrated efficient light emission and signal c... |
5730c6cbf6cb411900e24488 | At what global company was the first visible-spectrum LED developed? | General Electric Company | [
"Light-emitting_diode\n\nThe first visible-spectrum (red) LED was developed in 1962 by Nick Holonyak, Jr., while working at General Electric Company. Holonyak first reported his LED in the journal Applied Physics Letters on the December 1, 1962. M. George Craford, a former graduate student of Holonyak, invented the... |
5730c6cbf6cb411900e24489 | What GE employee developed the visible-spectrum LED? | Nick Holonyak, Jr. | [
"Light-emitting_diode\n\nThe first visible-spectrum (red) LED was developed in 1962 by Nick Holonyak, Jr., while working at General Electric Company. Holonyak first reported his LED in the journal Applied Physics Letters on the December 1, 1962. M. George Craford, a former graduate student of Holonyak, invented the... |
5730c6cbf6cb411900e2448a | What color is associated with the visible-spectrum LED? | red | [
"Light-emitting_diode\n\nThe first visible-spectrum (red) LED was developed in 1962 by Nick Holonyak, Jr., while working at General Electric Company. Holonyak first reported his LED in the journal Applied Physics Letters on the December 1, 1962. M. George Craford, a former graduate student of Holonyak, invented the... |
5730c6cbf6cb411900e2448b | What color LED was later created in 1972? | yellow | [
"Light-emitting_diode\n\nThe first visible-spectrum (red) LED was developed in 1962 by Nick Holonyak, Jr., while working at General Electric Company. Holonyak first reported his LED in the journal Applied Physics Letters on the December 1, 1962. M. George Craford, a former graduate student of Holonyak, invented the... |
5730c6cbf6cb411900e2448c | What graduate student of Holonyak created the yellow LED? | M. George Craford | [
"Light-emitting_diode\n\nThe first visible-spectrum (red) LED was developed in 1962 by Nick Holonyak, Jr., while working at General Electric Company. Holonyak first reported his LED in the journal Applied Physics Letters on the December 1, 1962. M. George Craford, a former graduate student of Holonyak, invented the... |
5730c888aca1c71400fe5ab7 | What was the first commercial uses of LEDs? | replacements for incandescent and neon indicator lamps | [
"Light-emitting_diode\n\nThe first commercial LEDs were commonly used as replacements for incandescent and neon indicator lamps, and in seven-segment displays, first in expensive equipment such as laboratory and electronics test equipment, then later in such appliances as TVs, radios, telephones, calculators, as we... |
5730c888aca1c71400fe5ab8 | How much did the early LEDs cost? | US$200 per unit | [
"Light-emitting_diode\n\nThe first commercial LEDs were commonly used as replacements for incandescent and neon indicator lamps, and in seven-segment displays, first in expensive equipment such as laboratory and electronics test equipment, then later in such appliances as TVs, radios, telephones, calculators, as we... |
5730c888aca1c71400fe5ab9 | What was one use of early LED light in products? | calculators | [
"Light-emitting_diode\n\nThe first commercial LEDs were commonly used as replacements for incandescent and neon indicator lamps, and in seven-segment displays, first in expensive equipment such as laboratory and electronics test equipment, then later in such appliances as TVs, radios, telephones, calculators, as we... |
5730c888aca1c71400fe5aba | What modern company introduced LEDs in 1968? | Hewlett Packard (HP) | [
"Light-emitting_diode\n\nThe first commercial LEDs were commonly used as replacements for incandescent and neon indicator lamps, and in seven-segment displays, first in expensive equipment such as laboratory and electronics test equipment, then later in such appliances as TVs, radios, telephones, calculators, as we... |
5730c888aca1c71400fe5abb | In what decade were production costs greatly reduced for LEDs to enable successful commercial uses? | 1970s | [
"Light-emitting_diode\n\nThe first commercial LEDs were commonly used as replacements for incandescent and neon indicator lamps, and in seven-segment displays, first in expensive equipment such as laboratory and electronics test equipment, then later in such appliances as TVs, radios, telephones, calculators, as we... |
5730f39205b4da19006bcc7e | What color LED was demonstrated in 1994? | blue | [
"Light-emitting_diode\n\nThe first high-brightness blue LED was demonstrated by Shuji Nakamura of Nichia Corporation in 1994 and was based on InGaN. In parallel, Isamu Akasaki and Hiroshi Amano in Nagoya were working on developing the important GaN nucleation on sapphire substrates and the demonstration of p-type d... |
5730f39205b4da19006bcc7f | Who demonstrated the first blue LED? | Shuji Nakamura | [
"Light-emitting_diode\n\nThe first high-brightness blue LED was demonstrated by Shuji Nakamura of Nichia Corporation in 1994 and was based on InGaN. In parallel, Isamu Akasaki and Hiroshi Amano in Nagoya were working on developing the important GaN nucleation on sapphire substrates and the demonstration of p-type d... |
5730f39205b4da19006bcc80 | What did Nakamura, Akasaki, and Amano receive for their work? | 2014 Nobel prize in physics | [
"Light-emitting_diode\n\nThe first high-brightness blue LED was demonstrated by Shuji Nakamura of Nichia Corporation in 1994 and was based on InGaN. In parallel, Isamu Akasaki and Hiroshi Amano in Nagoya were working on developing the important GaN nucleation on sapphire substrates and the demonstration of p-type d... |
5730f39205b4da19006bcc81 | Who investigated the efficiency of high-brightness LED at Cardiff University in 1995? | Alberto Barbieri | [
"Light-emitting_diode\n\nThe first high-brightness blue LED was demonstrated by Shuji Nakamura of Nichia Corporation in 1994 and was based on InGaN. In parallel, Isamu Akasaki and Hiroshi Amano in Nagoya were working on developing the important GaN nucleation on sapphire substrates and the demonstration of p-type d... |
5730f39205b4da19006bcc82 | What substance did Barbieri use in his work with high-brightness LED? | indium tin oxide | [
"Light-emitting_diode\n\nThe first high-brightness blue LED was demonstrated by Shuji Nakamura of Nichia Corporation in 1994 and was based on InGaN. In parallel, Isamu Akasaki and Hiroshi Amano in Nagoya were working on developing the important GaN nucleation on sapphire substrates and the demonstration of p-type d... |
5730f4c0497a881900248aad | What LED quickly followed the blue LEDs? | white | [
"Light-emitting_diode\n\nThe attainment of high efficiency in blue LEDs was quickly followed by the development of the first white LED. In this device a Y\n3Al\n5O\n12:Ce (known as \"YAG\") phosphor coating on the emitter absorbs some of the blue emission and produces yellow light through fluorescence. The combinat... |
5730f4c0497a881900248aaf | What does the YAG phosphor coating produce? | yellow light | [
"Light-emitting_diode\n\nThe attainment of high efficiency in blue LEDs was quickly followed by the development of the first white LED. In this device a Y\n3Al\n5O\n12:Ce (known as \"YAG\") phosphor coating on the emitter absorbs some of the blue emission and produces yellow light through fluorescence. The combinat... |
5730f7c9e6313a140071cb0c | What converts absorbed light energy into an electric current? | P-N junction | [
"Light-emitting_diode\n\nA P-N junction can convert absorbed light energy into a proportional electric current. The same process is reversed here (i.e. the P-N junction emits light when electrical energy is applied to it). This phenomenon is generally called electroluminescence, which can be defined as the emission... |
5730f7c9e6313a140071cb0d | What is the phenomenon where a P-N junction emits light when an electrical current is applied to it? | electroluminescence | [
"Light-emitting_diode\n\nA P-N junction can convert absorbed light energy into a proportional electric current. The same process is reversed here (i.e. the P-N junction emits light when electrical energy is applied to it). This phenomenon is generally called electroluminescence, which can be defined as the emission... |
5730f7c9e6313a140071cb0e | Where are the free electrons located in the production of electroluminescence? | the conduction band | [
"Light-emitting_diode\n\nA P-N junction can convert absorbed light energy into a proportional electric current. The same process is reversed here (i.e. the P-N junction emits light when electrical energy is applied to it). This phenomenon is generally called electroluminescence, which can be defined as the emission... |
5730f7c9e6313a140071cb0f | Whose energy levels are lower than the electrons in the electroluminescence process? | holes existing in the P-region | [
"Light-emitting_diode\n\nA P-N junction can convert absorbed light energy into a proportional electric current. The same process is reversed here (i.e. the P-N junction emits light when electrical energy is applied to it). This phenomenon is generally called electroluminescence, which can be defined as the emission... |
5730f7c9e6313a140071cb10 | Why is some energy in the electroluminescence process emitted as heat and light? | to recombine the electrons and the holes | [
"Light-emitting_diode\n\nA P-N junction can convert absorbed light energy into a proportional electric current. The same process is reversed here (i.e. the P-N junction emits light when electrical energy is applied to it). This phenomenon is generally called electroluminescence, which can be defined as the emission... |
5730f8caa5e9cc1400cdbb55 | In what year was a new type of blue LED produced? | 2003 | [
"Light-emitting_diode\n\nIn September 2003, a new type of blue LED was demonstrated by Cree that consumes 24 mW at 20 milliamperes (mA). This produced a commercially packaged white light giving 65 lm/W at 20 mA, becoming the brightest white LED commercially available at the time, and more than four times as efficie... |
5730f8caa5e9cc1400cdbb56 | Who demonstrated in 2003 the new type of blue LED? | Cree | [
"Light-emitting_diode\n\nIn September 2003, a new type of blue LED was demonstrated by Cree that consumes 24 mW at 20 milliamperes (mA). This produced a commercially packaged white light giving 65 lm/W at 20 mA, becoming the brightest white LED commercially available at the time, and more than four times as efficie... |
5730f8caa5e9cc1400cdbb57 | How much more efficient as standard incandescents was the white LED commercially available in 2003? | four times | [
"Light-emitting_diode\n\nIn September 2003, a new type of blue LED was demonstrated by Cree that consumes 24 mW at 20 milliamperes (mA). This produced a commercially packaged white light giving 65 lm/W at 20 mA, becoming the brightest white LED commercially available at the time, and more than four times as efficie... |
5730f8caa5e9cc1400cdbb58 | What is the typical operating current for high-power LEDs? | 350 mA | [
"Light-emitting_diode\n\nIn September 2003, a new type of blue LED was demonstrated by Cree that consumes 24 mW at 20 milliamperes (mA). This produced a commercially packaged white light giving 65 lm/W at 20 mA, becoming the brightest white LED commercially available at the time, and more than four times as efficie... |
5730fa4b05b4da19006bccae | What is a symptom of LED failure? | loss of efficiency | [
"Light-emitting_diode\n\nThe most common symptom of LED (and diode laser) failure is the gradual lowering of light output and loss of efficiency. Sudden failures, although rare, can also occur. Early red LEDs were notable for their short service life. With the development of high-power LEDs the devices are subjecte... |
5730fa4b05b4da19006bccaf | What is rare in LED lighting? | Sudden failures | [
"Light-emitting_diode\n\nThe most common symptom of LED (and diode laser) failure is the gradual lowering of light output and loss of efficiency. Sudden failures, although rare, can also occur. Early red LEDs were notable for their short service life. With the development of high-power LEDs the devices are subjecte... |
5730fa4b05b4da19006bccb0 | What was notable in early red LEDs? | their short service life | [
"Light-emitting_diode\n\nThe most common symptom of LED (and diode laser) failure is the gradual lowering of light output and loss of efficiency. Sudden failures, although rare, can also occur. Early red LEDs were notable for their short service life. With the development of high-power LEDs the devices are subjecte... |
5730fa4b05b4da19006bccb1 | What could cause early light-output degradation in LEDs? | higher junction temperatures | [
"Light-emitting_diode\n\nThe most common symptom of LED (and diode laser) failure is the gradual lowering of light output and loss of efficiency. Sudden failures, although rare, can also occur. Early red LEDs were notable for their short service life. With the development of high-power LEDs the devices are subjecte... |
5730fa4b05b4da19006bccb2 | What is a classification used in LED lighting to describe how much usefulness it will receive? | L70 or L50 | [
"Light-emitting_diode\n\nThe most common symptom of LED (and diode laser) failure is the gradual lowering of light output and loss of efficiency. Sudden failures, although rare, can also occur. Early red LEDs were notable for their short service life. With the development of high-power LEDs the devices are subjecte... |
5730fb1b05b4da19006bccb8 | LED efficacy is inversely proportional to what? | operating temperature | [
"Light-emitting_diode\n\nSince LED efficacy is inversely proportional to operating temperature, LED technology is well suited for supermarket freezer lighting. Because LEDs produce less waste heat than incandescent lamps, their use in freezers can save on refrigeration costs as well. However, they may be more susce... |
5730fb1b05b4da19006bccb9 | Where is LED lighting very well suited? | supermarket freezer | [
"Light-emitting_diode\n\nSince LED efficacy is inversely proportional to operating temperature, LED technology is well suited for supermarket freezer lighting. Because LEDs produce less waste heat than incandescent lamps, their use in freezers can save on refrigeration costs as well. However, they may be more susce... |
5730fb1b05b4da19006bccba | LEDs produce less waste heat than what other device? | incandescent lamps | [
"Light-emitting_diode\n\nSince LED efficacy is inversely proportional to operating temperature, LED technology is well suited for supermarket freezer lighting. Because LEDs produce less waste heat than incandescent lamps, their use in freezers can save on refrigeration costs as well. However, they may be more susce... |
5730fb1b05b4da19006bccbb | What is LED lighting more susceptible to than incandescent light? | frost | [
"Light-emitting_diode\n\nSince LED efficacy is inversely proportional to operating temperature, LED technology is well suited for supermarket freezer lighting. Because LEDs produce less waste heat than incandescent lamps, their use in freezers can save on refrigeration costs as well. However, they may be more susce... |
5731085e497a881900248b1b | The first blue-violet LED was developed at what University? | Stanford | [
"Light-emitting_diode\n\nThe first blue-violet LED using magnesium-doped gallium nitride was made at Stanford University in 1972 by Herb Maruska and Wally Rhines, doctoral students in materials science and engineering. At the time Maruska was on leave from RCA Laboratories, where he collaborated with Jacques Pankov... |
5731085e497a881900248b1c | When was the first blue-violet LED developed? | 1972 | [
"Light-emitting_diode\n\nThe first blue-violet LED using magnesium-doped gallium nitride was made at Stanford University in 1972 by Herb Maruska and Wally Rhines, doctoral students in materials science and engineering. At the time Maruska was on leave from RCA Laboratories, where he collaborated with Jacques Pankov... |
5731085e497a881900248b1d | What students developed the first blue-violet LED? | Herb Maruska and Wally Rhines | [
"Light-emitting_diode\n\nThe first blue-violet LED using magnesium-doped gallium nitride was made at Stanford University in 1972 by Herb Maruska and Wally Rhines, doctoral students in materials science and engineering. At the time Maruska was on leave from RCA Laboratories, where he collaborated with Jacques Pankov... |
5731085e497a881900248b1e | What substance helped demonstrate the first blue electroluminescence? | zinc-doped gallium nitride | [
"Light-emitting_diode\n\nThe first blue-violet LED using magnesium-doped gallium nitride was made at Stanford University in 1972 by Herb Maruska and Wally Rhines, doctoral students in materials science and engineering. At the time Maruska was on leave from RCA Laboratories, where he collaborated with Jacques Pankov... |
57310d75497a881900248b47 | In what decade were breakthroughs made that brought in the modern era of GaN-based optoelectronic devices? | 1980s | [
"Light-emitting_diode\n\nIn the late 1980s, key breakthroughs in GaN epitaxial growth and p-type doping ushered in the modern era of GaN-based optoelectronic devices. Building upon this foundation, Dr. Moustakas at Boston University patented a method for producing high-brightness blue LEDs using a new two-step proc... |
57310d75497a881900248b48 | Who first patented a method to produce high-brightness blue LEDs? | Shuji Nakamura | [
"Light-emitting_diode\n\nIn the late 1980s, key breakthroughs in GaN epitaxial growth and p-type doping ushered in the modern era of GaN-based optoelectronic devices. Building upon this foundation, Dr. Moustakas at Boston University patented a method for producing high-brightness blue LEDs using a new two-step proc... |
57310d75497a881900248b49 | Who first invented a method to produce high-brightness blue LEDs? | Dr. Moustakas | [
"Light-emitting_diode\n\nIn the late 1980s, key breakthroughs in GaN epitaxial growth and p-type doping ushered in the modern era of GaN-based optoelectronic devices. Building upon this foundation, Dr. Moustakas at Boston University patented a method for producing high-brightness blue LEDs using a new two-step proc... |
57310d75497a881900248b4a | What technology was made possible by high-power blue light sources? | BlueRay | [
"Light-emitting_diode\n\nIn the late 1980s, key breakthroughs in GaN epitaxial growth and p-type doping ushered in the modern era of GaN-based optoelectronic devices. Building upon this foundation, Dr. Moustakas at Boston University patented a method for producing high-brightness blue LEDs using a new two-step proc... |
57310d75497a881900248b4b | What is one modern gadget that benefits from high-power blue LED lighting? | tablets | [
"Light-emitting_diode\n\nIn the late 1980s, key breakthroughs in GaN epitaxial growth and p-type doping ushered in the modern era of GaN-based optoelectronic devices. Building upon this foundation, Dr. Moustakas at Boston University patented a method for producing high-brightness blue LEDs using a new two-step proc... |
573111b1e6313a140071cbe2 | What Nobel Prize did Nakamura, Amano, and Akasaki receive in 2014? | Physics | [
"Light-emitting_diode\n\nNakamura was awarded the 2006 Millennium Technology Prize for his invention. Nakamura, Hiroshi Amano and Isamu Akasaki were awarded the Nobel Prize in Physics in 2014 for the invention of the blue LED. In 2015, a US court ruled that three companies (i.e. the litigants who had not previously... |
573111b1e6313a140071cbe3 | What award did Nakamura receive in 2006 for his invention? | Millennium Technology Prize | [
"Light-emitting_diode\n\nNakamura was awarded the 2006 Millennium Technology Prize for his invention. Nakamura, Hiroshi Amano and Isamu Akasaki were awarded the Nobel Prize in Physics in 2014 for the invention of the blue LED. In 2015, a US court ruled that three companies (i.e. the litigants who had not previously... |
573111b1e6313a140071cbe4 | How many companies did a judge say infringed on Dr. Moustakas's prior blue light patent in 2015? | three | [
"Light-emitting_diode\n\nNakamura was awarded the 2006 Millennium Technology Prize for his invention. Nakamura, Hiroshi Amano and Isamu Akasaki were awarded the Nobel Prize in Physics in 2014 for the invention of the blue LED. In 2015, a US court ruled that three companies (i.e. the litigants who had not previously... |
573111b1e6313a140071cbe5 | What was the fine given to the three companies? | not less than 13 million USD | [
"Light-emitting_diode\n\nNakamura was awarded the 2006 Millennium Technology Prize for his invention. Nakamura, Hiroshi Amano and Isamu Akasaki were awarded the Nobel Prize in Physics in 2014 for the invention of the blue LED. In 2015, a US court ruled that three companies (i.e. the litigants who had not previously... |
573112cae6313a140071cbf0 | What are cladding layers? | active region consisting of one or more InGaN quantum wells sandwiched between thicker layers of GaN | [
"Light-emitting_diode\n\nBy the late 1990s, blue LEDs became widely available. They have an active region consisting of one or more InGaN quantum wells sandwiched between thicker layers of GaN, called cladding layers. By varying the relative In/Ga fraction in the InGaN quantum wells, the light emission can in theor... |
573112cae6313a140071cbf1 | How can light emission be varied from violet to amber? | By varying the relative In/Ga fraction in the InGaN quantum wells | [
"Light-emitting_diode\n\nBy the late 1990s, blue LEDs became widely available. They have an active region consisting of one or more InGaN quantum wells sandwiched between thicker layers of GaN, called cladding layers. By varying the relative In/Ga fraction in the InGaN quantum wells, the light emission can in theor... |
573112cae6313a140071cbf2 | What does AlGaN stand for? | Aluminium gallium nitride | [
"Light-emitting_diode\n\nBy the late 1990s, blue LEDs became widely available. They have an active region consisting of one or more InGaN quantum wells sandwiched between thicker layers of GaN, called cladding layers. By varying the relative In/Ga fraction in the InGaN quantum wells, the light emission can in theor... |
573112cae6313a140071cbf3 | What LEDs are more efficient when produced from the InGaN/GaN systems than without? | Green | [
"Light-emitting_diode\n\nBy the late 1990s, blue LEDs became widely available. They have an active region consisting of one or more InGaN quantum wells sandwiched between thicker layers of GaN, called cladding layers. By varying the relative In/Ga fraction in the InGaN quantum wells, the light emission can in theor... |
573113d805b4da19006bcd56 | What substance does nitrides contain? | aluminium | [
"Light-emitting_diode\n\nWith nitrides containing aluminium, most often AlGaN and AlGaInN, even shorter wavelengths are achievable. Ultraviolet LEDs in a range of wavelengths are becoming available on the market. Near-UV emitters at wavelengths around 375–395 nm are already cheap and often encountered, for example,... |
573113d805b4da19006bcd57 | What sort of LEDs are becoming more available on the market? | Ultraviolet | [
"Light-emitting_diode\n\nWith nitrides containing aluminium, most often AlGaN and AlGaInN, even shorter wavelengths are achievable. Ultraviolet LEDs in a range of wavelengths are becoming available on the market. Near-UV emitters at wavelengths around 375–395 nm are already cheap and often encountered, for example,... |
573113d805b4da19006bcd58 | What is the range of wavelengths for cheap UV LEDs? | 375–395 nm | [
"Light-emitting_diode\n\nWith nitrides containing aluminium, most often AlGaN and AlGaInN, even shorter wavelengths are achievable. Ultraviolet LEDs in a range of wavelengths are becoming available on the market. Near-UV emitters at wavelengths around 375–395 nm are already cheap and often encountered, for example,... |
573113d805b4da19006bcd59 | Shorter wavelength diodes provide wavelengths as low as what? | 240 nm | [
"Light-emitting_diode\n\nWith nitrides containing aluminium, most often AlGaN and AlGaInN, even shorter wavelengths are achievable. Ultraviolet LEDs in a range of wavelengths are becoming available on the market. Near-UV emitters at wavelengths around 375–395 nm are already cheap and often encountered, for example,... |
573113d805b4da19006bcd5a | What UV wavelengths are found in sterilization devices? | 250–270 nm | [
"Light-emitting_diode\n\nWith nitrides containing aluminium, most often AlGaN and AlGaInN, even shorter wavelengths are achievable. Ultraviolet LEDs in a range of wavelengths are becoming available on the market. Near-UV emitters at wavelengths around 375–395 nm are already cheap and often encountered, for example,... |
5731151605b4da19006bcd74 | What colors are used to form white light? | red, green, and blue | [
"Light-emitting_diode\n\nWhite light can be formed by mixing differently colored lights; the most common method is to use red, green, and blue (RGB). Hence the method is called multi-color white LEDs (sometimes referred to as RGB LEDs). Because these need electronic circuits to control the blending and diffusion of... |
5731151605b4da19006bcd75 | What is the method called that mixes red, green, and blue colors to form white light? | multi-color white LEDs | [
"Light-emitting_diode\n\nWhite light can be formed by mixing differently colored lights; the most common method is to use red, green, and blue (RGB). Hence the method is called multi-color white LEDs (sometimes referred to as RGB LEDs). Because these need electronic circuits to control the blending and diffusion of... |
5731151605b4da19006bcd76 | What does the multi-color white LED method need to produce the end result? | electronic circuits | [
"Light-emitting_diode\n\nWhite light can be formed by mixing differently colored lights; the most common method is to use red, green, and blue (RGB). Hence the method is called multi-color white LEDs (sometimes referred to as RGB LEDs). Because these need electronic circuits to control the blending and diffusion of... |
5731151605b4da19006bcd77 | What is another name to reference the multi-color white LED method? | RGB LEDs | [
"Light-emitting_diode\n\nWhite light can be formed by mixing differently colored lights; the most common method is to use red, green, and blue (RGB). Hence the method is called multi-color white LEDs (sometimes referred to as RGB LEDs). Because these need electronic circuits to control the blending and diffusion of... |
5731162005b4da19006bcd7c | What is one type of multi-color white LED? | tetrachromatic | [
"Light-emitting_diode\n\nThere are several types of multi-color white LEDs: di-, tri-, and tetrachromatic white LEDs. Several key factors that play among these different methods, include color stability, color rendering capability, and luminous efficacy. Often, higher efficiency will mean lower color rendering, pre... |
5731162005b4da19006bcd7d | What is a factor that may be different in the various types of multi-color white LEDs? | luminous efficacy | [
"Light-emitting_diode\n\nThere are several types of multi-color white LEDs: di-, tri-, and tetrachromatic white LEDs. Several key factors that play among these different methods, include color stability, color rendering capability, and luminous efficacy. Often, higher efficiency will mean lower color rendering, pre... |
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