Photo "Hikari no Mi" with a faint smile drawn on the tip of a branch = 18th, Fukushima-ku, Osaka
Light art "Nakanoshima West Winter Story" opens
If you write the contents roughly
This is an annual project in which a light-emitting diode (LED) light is built into a bag that depicts the smiles of children and children, and the trees are decorated and lit. "Smiles" were sent from about 2 people, which is about twice as many.
"Nakanoshima West Winter Story 2020", which decorates various light arts along the Dojima River that flows through Osaka City, will be on the night of the 18th ... → Continue reading
Osaka Nichi-Nichi Newspaper
Wikipedia related words
If there is no explanation, there is no corresponding item on Wikipedia.
Light emitting diode
Light emitting diode(Hakko diode,British: light emitting diode: LED) IsdiodeIs a kind ofForward[Note 1]ToVoltageWhen you addLuminousToSemiconductor elementIs.In the light emission principleElectroluminescence The (EL) effect is used.Also,Organic electroluminescence(OLEDs[Note 2], Organic EL) is also included in the LED for classification.
1962,Nick HolonyakInvented by..At the time of invention, it was only red.1972ToInvented the yellow-green LED.1986,Akasaki IsamuAnd the studentsAmano HiroshiBecomes a blue LED luminescent crystalGallium nitrideWas created for the first time in the world, followed byIn 1989pn junctionThe blue LED was invented.Based on this inventionToyoda GoseiとNichiaAimed at the industrialization of blue LEDs.1993,NTT Physical Science LaboratoryA luminescent substance produced by Takashi MatsuokaIndium gallium nitrideA high-brightness blue LED that can withstand practical use is produced by Nichia Corporation, and Shuji Nakamura won the Nobel Prize in Physics in 2014.
Light emitting diodesemiconductorUsedpn junctionIt is made with a structure called.Luminescence is in thisElectronicHaveEnergyIs done by directly converting to light energy, macroscopicallyheat,motionDoes not require the intervention of.electrodeWith the electrons injected into the semiconductor fromHoleWas differentEnergy band(Conduction bandとValence band), Near the pn junctionBandgapBeyondRejoinTo do.At the time of rejoiningBand gapEnergy almost equivalent to (forbidden band width)LightIs released as.Of the emitted lightwavelengthIs determined by the bandgap of the material, whichInfraredFrom the areaVisible lightregion,UVVarious luminescence can be obtained up to the region, but basically it is a single color and the degree of freedom is low.However, blue, red, green (Three primary colors of lightBy using a combination of light emitting diodes of), all colors (フ ル カ ラ ー) Can be expressed.Also, on the surface of light emitting diodes that emit blue or ultraviolet light.Fluorescent paintBy applyinglight bulbVarious colors etc.Neutral colorLight emitting diodes are also manufactured.
Other commondiodeHas the same polarity asCathodeAgainst (cathode)anodeUse by applying a positive voltage to (anode).Even if you raise the voltage while the voltage is low電流Does not increase and does not emit light.When a certain voltage is exceeded, the current increases rapidly with respect to the voltage rise, and light is emitted according to the amount of current.This voltage is referred to as "forward voltage drop (V).F) ”, But generalsiliconCompared to diodes, light emitting diodes have a higher forward voltage drop.It depends on the emission color, but it is about 1.4V in infrared.About 2.1V for red, orange, yellow, and green.About 3.5V for white and blue.UV LED is the most VFIs high and requires 4.5 to 6V.
The current consumption during light emission is about several mA to 50 mA for indicator lights, but high-power light-emitting diodes with power consumption of several tens of watts are also sold for lighting applications..
When voltage is applied in the opposite directionWithstand voltageIs much lower than a normal silicon diode, usually around -5V.If it exceeds this, it will be destroyed, soRectificationCannot be used for any purpose.
- Wavelength bias
- Fluorescent light,Incandescent lampUnlike many other light sources, the light is biased to a specific wavelength.Therefore, for the corresponding wavelengthPhotochemical reactionOn the contrary, sufficient effect may not be obtained because there is no light of the wavelength required for the brightness.
- As an effective use, depending on the type of light source, it is easy to obtain light that does not contain unnecessary ultraviolet rays or infrared rays, so it is sensitive to ultraviolet rays.Cultural property,artUsed for lighting works and objects that dislike heat irradiation.It also has the effect of promoting the growth of plants that prefer light of a specific wavelength.
- On the contrary, even if it is bright, there is no light of a specific wavelength, so when it is used as lighting, it may hinder the growth of animals and plants.For exampleVitamin DIt is deficient because it does not contain the wavelength required for the production of photosynthesis, and its growth is inhibited because it does not contain the wavelength required for photosynthesis.In particular, in the method of producing white light emission by the three-color LED method, the harmful effect due to the wavelength distribution becomes remarkable.
- There is also a white type that diffuses the wavelength distribution using a phosphor, but even in that case, light with a particularly strong wavelength is distributed in the blue part, which is the original wavelength of the light source.
- Flickering switching speed
- The response of the optical output to changes in the input current is fast, and it is also used for communication, etc. When used for lighting, the maximum amount of light can be obtained at the same time as lighting.
- Because the structure is simplemass productionCan.
- Price is red LED 1 piece 5Yen ――It is cheap as about 10 yen.
- Unlike a light bulbfilamentBecause it does not use, it is lightweight, strong against impact, and has a long life.malfunctionThe frequency of occurrence is also low.
Since the amount of light is basically proportional to the current, the average current is controlled to be constant.High frequency circuitDriven by.The AC power supply is rectified and used.
Current limiting resistor
To pass the current I with the power supply voltage as E, the appropriate resistance value is approximately (EV).F) / I, but the LED forward voltage drop (V)F) Has individual differences, and the voltage applied to the resistor changes, so the current flowing through the actually manufactured product will vary slightly from the value assumed at the time of design.
Resistors also consume power, so power efficiency is not good, but if a constant voltage power supply can be prepared, it will be the simplest and lowest cost circuit.Therefore, it is often used for indicator lamps that do not particularly pursue luminous efficiency.
Constant current drive
Constant current diode (CRD)seriesConnect to, etc.Active elementBy configuring a constant current circuit withAutomobile,bike OfbatteryIt can be used even in an environment where the power supply voltage fluctuates to some extent.
In addition to the forward voltage drop of the LED, the power supply requires the voltage required for the operation of the constant current circuit. CRD requires a voltage of about 5 to 10V for operation, but it can operate at the same level as CRD with a voltage of about 1V.ICIs also used.
The circuit is simple, but like the current limiting resistor, it consumes and absorbs an excessive power supply voltage, resulting in poor power efficiency depending on the power supply voltage.
High frequency drive
It repeats blinking in a short time cycle that human vision cannot recognize, and obtains a constant brightness in appearance.Brightness is the lighting timeDuty ratiochangePulse width modulationCan be adjusted more easily.
The drive circuit has good power efficiency, but the output fluctuates with current and voltage (Ripple)Switching power supplyAnd can be used.Also, by keeping the average output current constant,Dry cellIt is possible to maintain a constant brightness even when the power supply voltage is low or the fluctuation range is large.
The power consumption of the drive circuit is less than that of other drive methods, and most of the input power is consumed by the LED, so the power efficiency is relatively good.However, it is caused by a sudden change in current when the current is interrupted.noiseRadiation goes inside and outside the deviceCauses electromagnetic interferenceIn addition, as the circuit scale increasescostとImplementationThe volume increases.
Knowledge required for use
- The intensity of the emitted light is approximately proportional to the amount of electric current.However, efficiency decreases especially in the large current range.
- Although the amount of heat generated is small, high-power products generate heat accordingly.Since it is sensitive to heat, the need for heat dissipation is higher than that of incandescent bulbs and fluorescent lamps.heatsinkIf heat is not dissipated properly due to such factors, the advantages of light emitting diodes will be lost due to reduced efficiency and shortened life, and smoke will be emitted.IgnitionIt may lead to an accident such as.
- Do not exceed continuous maximum current or instantaneous maximum current.RatingHigh when a current larger than the current is passedbeamIs obtained, but the life is extremely shortened. Some commercial products that use LEDs have high brightness at the expense of life, and some omit the circuit that limits the current in order to keep the price down.
- polarityBecause there isanodeとCathodeDoes not emit light when applied by mistake.In addition, the withstand voltage in the opposite direction is low, and it is easily destroyed.For applications such as wedge balls of automobiles and motorcycles, where the polarity is not known until the polarity is inserted, or where the alternator's alternating current directly enters, there are also those that have a bridge circuit sandwiched between them to make them non-polar.
- ParallelBe careful when connecting..Forward voltage drop (V)F) Has individual differences, and when connected in parallel, the current concentrates only on the element with the lowest forward voltage drop (simply speaking, the voltage at which the current begins to flow).Further heat generation due to current concentrationElectric resistanceAnd VFA vicious cycle occurs in which the value of is reduced and the concentration of current is further promoted.Not only does the amount of light emitted become non-uniform, but if the current exceeds the maximum rating, there is a risk of shortening the life due to overheating and burning.If the element destruction was in open mode, then VFA large amount of current is concentrated on the element with a low value, and the destruction progresses in a chain.When turning on multiple LEDs at the same time, as much as possibleseriesA circuit whose constant current is controlled by a resistor or an active element is set as one unit, and this unit circuit is connected to the power supply in parallel.However, there are some products in which multiple elements are internally connected in parallel..
- Light emitting diodes such as GaNStatic electricity,Surge currentWeak to.
- lensIn the case of a light emitting diode with, of the elementoptical axisThe directions of the light actually emitted do not usually match and are slightly different due to variations in the manufacturing process.
- Since the light is biased to a specific frequency, the light is stronger than the apparent brightness, and the photochemical reaction by the light of the corresponding frequency is promoted.For example, as with other light emitting devices, if you look directly at it,EyeMay have an adverse effect on.This tendency is especially strong for ultraviolet rays and those with high output.
Of the emitted lightwavelength(Color) Ispn junctionOf the material that formsBand gapThe size of is related.For the light emitting diode, a semiconductor material having a band gap corresponding to wavelengths up to near infrared rays, visible light, and ultraviolet rays is used.In general, light emitting diodes have a high probability of emission recombination.Direct transitionWhile type semiconductors are suitable, they are common semiconductor materials.Silicon(Silicon)germaniumな どIndirect transitionIn type semiconductors, light is less likely to be emitted when electrons and holes recombine.However, there are also materials that emit strong light through the level of doped impurities such as GaAsP and GaP, which have long been used for yellow and yellow-green, and are widely used.
By using the following materials, it is possible to produce light emitting diodes of various colors.
- (AlGaAs) --Infrared / Red
- Gallium Arsenide Phosphorus (GaAsP)-Red / Orange / Yellow
- Indium Gallium Nitride (InGaN) /Gallium nitride (GaN) / Aluminum Gallium Nitride (AlGaN)-Orange / Yellow / Green / Blue / Purple / Ultraviolet
- Gallium phosphide (GaP)-red, yellow, green
- Zinc selenide (ZnSe) --Green / Blue
- Aluminum Indium Gallium Phosphorus (AlGaInP)-Orange / Yellow Orange / Yellow / Green
- diamond (C)-Ultraviolet rays
- Zinc oxide (ZnO) --Blue / Purple / Near UV (under development)
- Perovskite semiconductor --Red / Yellow / Green
The following are used as substrates.
- Silicon carbideSubstrate (SiC)-blue
- sapphire(corundum) Substrate (Al2O3) --Blue
- Silicon Substrate (Si) --Blue (Research Stage)
Blue light emitting diode
Blue light emitting diodeGallium nitride Made of (GaN)blueIt is a light emitting diode that emits the light of.Blue LEDIs also written.Japanese chemical company,NichiaThe corporation has a large market share.As another leading company,Toyoda Gosei,Seiwa ElectricThere is. Development of light emitting diodes using GaN-based compounds, followed by blueSemiconductor laserWith the realization of this, semiconductor light emitting devices in the visible light short wavelength region from ultraviolet to pure green have been widely put into practical use.
Light emitting diodes can be driven with low powerlight sourcefor,displayIt was expected to be applied to.RGBbyフ ル カ ラ ーFor displayThree primary colors of light("Red"-绿-tag) Is required to have all the light emitting elements.1980 eraBy the middle of the year, only pure red was in practical use.
At that time, there were some that were sold under the name of "blue diode", but the color waspurplePractical high as pure blueLuminanceThere were no products that produced.AlsoYellowish greenThe color was put into practical use from early on along with red, but as a result, the same GaN-based semiconductor material as blue was required to realize pure green.Practical use of pure green LED has been since the advent of blue LEDIs.For these reasons, it was not possible to realize a full-color display using light emitting diodes.
To realize pure blue light emissionZinc selenide (ZnSe) compounds andSilicon carbide Research using (SiC) has been carried out for a long time, leading to the development of a blue-green-green light emitting diode based on the ZnSe system, and the blue light emitting diode of SiC has been put on the market with a weak emission intensity.However, since then, blue light emitting diodes made of GaN-based compounds have rapidly become widespread, and these material-based technologies are now being diverted to applications such as white light emitting devices and substrates.
Regarding the development of high-brightness blue LEDs using gallium nitride, 1986,Akasaki Isamu,Amano HiroshiSucceeded in producing high-quality, high-purity GaN crystals.Hiroshi Amano proved for the first time that "PN junction", which was considered impossible, is possible. In 1993Shuji NakamuraInvented and put into practical use a high-brightness blue LED ahead of the rest of the world (Ministry of Education, Culture, Sports, Science and Technology 28 White Paper on Science and Technology(See p20 and p28).
2001In August, Nakamura was on duty1993Invented in November (Employee invention) "404 patentI filed a lawsuit against Nichia Corporation, my former employer, and argued over the confirmation of the ownership of the patent to the plaintiff or the consideration for the transfer (Blue LED proceedings).This proceedingCompanyThe court has aroused public interest in the relationship between the inventor and the inventor.Tokyo District CourtThen, he evaluated the consideration for the invention as about 604 billion yen and ordered payment of 200 billion yen.Tokyo High Court ThesettlementThe price of the invention approved by the trial decision was 1 million yen, which is 604/1 of the price of about 100 billion yen.Nichia will pay about 6 million yen including (because the payment of the consideration was delayed anyway).settlementWas established.However, Nakamura was still unconvinced and stayed to point out that "the high court did not read a lot of documents submitted and decided the settlement amount from the beginning. The method of deciding the settlement plan of the high court is not justice." There was also an event of visiting Japan from the United States where I was doing.
2004December, Tohoku UniversityInstitute for Materials Research OfMasashi Kawasaki(Thin film electronic material chemistry) et al.'S research team is cheaperZinc oxideSucceeded in developing a blue light emitting diode using.It is also said to be a reinvention of the blue LED.This result was the same year12/19Attached English scientific journalNature MaterialsIt is announced in (electronic version).It may also replace the high cost gallium nitride.
White light emitting diode
WhiteLEDIs also written.White light is generally all visible lightSpectrumIt is a term that refers to light with continuous intensity over a region (light with a continuous spectrum).Since the light emission obtained by the light emitting diode is limited to a narrow wavelength range, although not as much as that of a laser, it is not possible to generate white light in this sense.However, for multicolored light such as white, it is possible to design the spectrum so that the human eye can recognize the same color even if the spectrum is different.Typically like a TVThree primary colors of lightTo mix orComplementary colorLight that is perceived as white can be generated by mixing the two related colors and designing them to an appropriate intensity ratio.This principle is used in white light emitting diodes, and some concrete methods have been devised.As a result, not only is the diode electrically easy to handle, such as DC drive at low voltage, but it is also highly efficient (low power consumption) as a light source, and its life is longer than that of existing light sources.LED lightingAs a white light emitting diode is used as a light source, it is becoming popular as a solid light source that does not use gas.
Fluorescent material method
A light emitting diode chip that emits light of blue or shorter wavelength is excited by the light of the light emitting diode and emits long wavelength light.Phosphor(Photoluminescence) Is combined.The light emitting diode chip is covered with a phosphor, and when lit, part or all of the light from the light emitting diode chip is absorbed by the phosphor.fluorescenceEmits light of longer wavelengths.If the chip of the light emitting diode emits blue light, the blue light from the chip is mixed with the light of the phosphor and output together.White light can be obtained by adjusting the fluorescence wavelength and the thickness of the phosphor.For this phosphor, for exampleYAGThe system is used.This method has the advantage that white light emission can be achieved with only a single chip and package.
The existence of a blue light emitting diode was indispensable for the realization of a white light emitting diode that emits light recognized as white.This is because light emitted by a phosphor does not produce light having a wavelength shorter than the light received by the phosphor, so that a red or green LED lacks a short wavelength component and is not recognized as white.With the development of the phosphor method, white light emitting diodes, which are solid light sources, have become widespread in earnest.
Pseudo white light emitting diode
It is the mainstream of current white light emitting diodes, and is generally bluish yellow.Pseudo whiteIt is called a light emitting diode.By combining a phosphor that fluoresces yellow, which is a wavelength with high luminosity, and a blue light emitting diode, a white light emitting diode that is visually very bright is realized.Nichia, which manufactures blue light emitting diodes, is good at this method because it is originally a manufacturer of phosphors.Toyoda Gosei also uses the same method.The white light emitting diode produced by this method is considered to be the world's first white light emitting diode.The realization of the pseudo-white light-emitting diode was modest because it was after the announcement of the blue light-emitting diode, which had a worldwide impact, but it was big news in the industry.
Pseudo white light emitting diode is very expensiveLamp efficiency The feature is that the (lm / W) value can be obtained.The reason isLuminosity factorIs related, and it is realized by combining the yellow of the phosphor whose spectrum is concentrated on the wavelength with high luminosity factor and the blue of the light emitting diode.Generally, humanretinaIs a cell tissue that identifies the intensity and color of light inConeHas high spectral sensitivity at yellow-green wavelengths (around 555 nm) (high luminosity factor).Therefore, if the emission of the phosphor is concentrated on the spectrum of this yellow-green wavelength, a person feels bright for the energy, and a white light emitting diode that is visually very bright can be realized. For white light emitting diodes exceeding 100 lm / W, in order to realize a pseudo white light emitting diode with high lamp efficiency,Total luminous fluxThe optimization has been made in consideration of the luminosity factor so as to increase the energy efficiency with respect to.The physical energy efficiency indicates the amount of physical energy.Radiant fluxIs calculated by dividing by the input power (watt), so it can be increased by increasing the light (number of photons) that can be extracted as light, but that alone is not highly efficient for luminosity factor. There may be a lot of light.In order to increase the lamp efficiency, it is necessary to obtain a spectrum that is physically efficient and suitable for luminosity factor.
In exchange for this, a pseudo-white light emitting diode designed with priority given to lamp efficiencyColor renderingIs likely to decrease.Generally, the average color rendering index (Ra) of a pseudo white light emitting diode is about 76.General fluorescent lamp It falls between (Ra67) and a three-wavelength fluorescent lamp (85).However, since the current color rendering index is based on incandescent lamps and fluorescent lamps, the color rendering index tends to be evaluated lower than the visual impression in the case of a light source having a steep spectrum such as a light emitting diode. ..For this reason, there is an argument to review the evaluation method so that the average color rendering index is higher for the light source having the above-mentioned characteristics..
High color rendering white light emitting diode
Blue light emitting diode and yellowPhosphorThe white light in the combination of the above has a low color rendering property because there are few spectral components of green and red.Luminous efficiency (lm / W) decreases when trying to improve color rendering by mixing non-yellow phosphors to improve the poor color development of red and crimson.[Note 3]..This is because even if a lot of red phosphors are mixed and a lot of light energy is generated in the red region, the human eye in this regionLuminosity factorBecause it is lowLamp efficiencyThe reason is that the above evaluation is low (above).In addition, it is difficult to accurately align the proportions of blue light that is transmitted and output, and there is a drawback that individual differences in color temperature during manufacturing are large.
In recent years, progress has been made in these points in terms of phosphors and emission wavelengths.For phosphors,Independent administrative agencyNational Institute for Materials ScienceSucceeded in developing a β-sialone phosphor, and it was said that the use of this would provide a significant improvement in lamp efficiency and solve the problem of red and crimson color development. It was confirmed that lowering the lamp efficiency is a physical limit and cannot be improved.In terms of emission wavelength, purple- UVLight emitting diodes have been developed (however, purple light emitting diodes have a problem of luminosity function that makes them look dark because they are close to the ultraviolet region).As a result, white light emitting diodes that emit multiple colors by excitation with purple light or ultraviolet light to improve color rendering properties have also appeared, as with fluorescent lamps..
White light emission by 3-color LED method
As another method for realizing white light emission, there is also a method of obtaining white as one light emitting source by using a chip of a red, green, and blue light emitting diode, which is the three primary colors of light...Since this method can obtain an arbitrary color by adjusting the amount of light of each LED, it is used as a light emitting element of a large image display device or a color electric bulletin board.However, it is not suitable for lighting.When considering the use as lighting, the phosphor method has a spectrum with a certain width, while the three-color LED method has only three sharp peaks of red, green, and blue, and yellow andcyanThe spectrum of is largely missing. Even if the white light emitted by the three-color LED system looks white, it is far from the white light of natural light (sunlight), so the hue of the object illuminated by it will be different from that of sunlight.Explain why the shades of illuminated objects look different.
Of the visible light
- An object that reflects red and green light and absorbs others
- An object that reflects only yellow light and absorbs others
Suppose there was.The light of the sun and incandescent bulbs contains visible light of all wavelengths, so below that, 1 reflects red and green light, stimulating the red and green cones of the retina and appearing yellow. In 2, yellow light is reflected, and the light stimulates both the red and green cones of the retina and appears yellow.In other words, both look yellow.However, when illuminated by a mixture of the three primary colors of light, 1 reflects red and green light and looks yellow, but 2 is absorbed by the object and looks black in theory.In reality, there is no object that reflects only yellow light and does not reflect any other light, so it is not so extreme that what should be yellow looks black, but the colors look a little different.Fluorescent lightThen, in order to solve this problem, there are 5 color emission and 7 color emission, but the color rendering property is still one step away from incandescent lamp.
This method requires three chips, and it is difficult to obtain a uniform emission color that does not depend on the viewing angle.Furthermore, since the voltage required by each chip is different, three lighting circuits are required.However, there is an advantage that the problem that the phosphor is deteriorated by heat generated from the chip of the light emitting diode can be avoided.Further, when it is used for display such as a liquid crystal backlight, it has an advantage that it has only three components of red, green, and blue, and it is possible to obtain a vivid display color with high color purity.
The basic structure of the light emitting diode is a pn junction, but in reality, in order to increase the luminous efficiencyDouble heterojunctionStructure and structure are used, technicallySemiconductor laserThere are many things in common with.As a manufacturing method, on the substrateChemical vapor deposition methodByfilmA method of stacking is used.Also,Perovskite semiconductorThen, it can be manufactured by a printing technique such as an inkjet.Further, like the semiconductor laser, there are a surface emitting type and an end surface emitting type.
The simplest structure consists of a transparent resin part containing a light emitting part and two terminals.Those with built-in multicolor LEDs have three or more terminals.
Gallium resource problem
indiumCompare withgalliumResources are not tight.However, the production area is mainlyChugoku,Eur-lex.europa.eu eur-lex.europa.eu,ウクライナPolitical ubiquitous and peculiar to these countriesCountry riskFrom this point of view, there is growing concern that semiconductor materials are too dependent on gallium.For this reason zinc oxide and silicon,Silicon carbideThere is an urgent need to realize a practical blue light emitting diode using such materials.
Low consumptionelectricityIt is used in many electronic devices due to its long life and small size.Especially,Mobile phoneIt can be said that it is adopted by making full use of its characteristics such as button lighting.In addition, there is also a structure that can produce a plurality of colors with one element.The color can be changed according to the operation mode of the device, contributing to the miniaturization of the device.
Initially, the brightness was low, so it was limited to indoor applications such as operation indicators for electronic devices, but after the red and yellow-green high-brightness types were put into practical use, they could be used outdoors.light bulbChange to formulaElectronic bulletin boardAdopted in, and even in the stationDeparture markIt came to be used for.
Since high-intensity blue and green, and white light-emitting diodes that apply them have become availableArenaVision etc.フ ル カ ラ ーLarge sizedisplay, As an alternative to light bulbs懐 中 电灯,traffic lights,AutomotiveTurn signal,Brake lamp, It is also used for various types of lighting.Especially when used for a brake lamp, the time lag between pressing the brake pedal and turning it on is shorter than that of a light bulb, which improves safety.2006Used Japan's first ultra-bright LEDHeadlightBut,JR Tokai Series 313 trainWas adopted by.2012Opened in NovemberTokyo Sky TreeThen, all the night lighting is done by LED.
Although the life of the light emitting diode itself is long, depending on the purpose of use, the decrease in luminous flux may accelerate due to deterioration of the resin, and when the luminous flux drops to the extent that LED replacement is required.substrateLarge scale including exchange ofmaintenanceWill be a future issue.In railway vehicles, we are trying to extend the life of the display device with fine control, such as turning off the side display when the side display reaches a certain speed while driving, from the idea that it should serve as a destination display at the station. There are also things..In many cases, the front display before and after knitting remains as it is.By the way, the side display isDot matrixDue to the control method of, it is difficult to visually recognize the displayed characters even if they continue to be displayed during high-speed movement.
Color blindnessIt may be difficult to distinguish the color of the light emitting diode.For example, the red, orange, yellow, yellow-green, and green LEDs look the same for people with color blindness of type 1 and type 2.traffictraffic lightsIn the above, green is changed to blue-green so that color vision deficiency can be identified, but measures for people with color vision deficiency other than traffic lights are required.
Rail and road since the 2000s when light emitting diode manufacturing costs began to fallTraffic lightsThe use in is also expanding.Energy ConservationAnd highly durable.Also,Incandescent light bulbIn the conventional method, which expresses colors by combining a color lens with a lens, sunlight enters the lamp to make the lens look bright and difficult to distinguish from the actual lighting location.This is called a pseudo lighting phenomenon.In a traffic light using a light emitting diode, the lens itself is colorless, and if the light emitting diode is not lit, it is colorless, so the pseudo lighting phenomenon is prevented.Sun lightIt is said that it is not easily affected by such factors.
In addition, there is a projector type that places an aggregate of high-brightness LEDs in the center and spreads the LED light evenly over the entire lens with a colorless and translucent reflector, and an element type that mounts multiple small elements on the entire surface. is there.
- drive recorder
- As with all LED lighting, not just traffic lights, it is really "lit" in the past.Incandescent light bulbUnlike LED lighting, it "blinks so fast that it cannot be followed by the human eye" to express lighting.In most cases, the blinking cycle is 60Hz in western Japan and 50Hz in eastern Japan.Normal video is 30 FPS, especially because it is just half of the cycle in western Japandrive recorder OfRecordingThe cycle in which the frame and LED are off is completelySyncIf this happens, there is a problem that all the signals appear to be off in the recorded recording.In order to prevent this, models that record by slightly shifting the recording frame rate of the drive recorder from the blinking cycle of the traffic light have come to be sold.
- Color problem
- Depending on the color, it may be difficult for people with color vision deficiency to see it, so various measures and research are being conducted.
- Snowy area problems
- SnowfallIn some regions, on the lighting surface of LED traffic lightssnowThere is a problem that the signal cannot be seen due to the adhesion.Previously it was melted by the heat generated by an incandescent light bulbSnow accretionHowever, this is because LEDs that generate less heat do not melt and accumulate.As measures against snow accretion, there are "flat type" where the lighting surface is flat and tilted downward, "snow accretion prevention mounting type" where the lighting surface is covered with a transparent capsule type hood, and the lighting surface. There is a "heater-mounted type" equipped with a heater.
Electric bulletin board / large video equipment
Of stationDeparture information display board,空港Conventional departure information boards, etc.Inverted flap typeAnd subtitles insteadRailway car,bus OfDestination display,Taxi(Super sign) etc.SceneInstead, it became popular.It is still sometimes called the LED rollsign.
The first LED display to appear was a three-color display system of red, yellow-green, and orange (orange is based on red and yellow-green LEDs).The third orange color is expressed by the red LED and the yellow-green LED, and it is also commonly called the "three-color LED method".However, since two-color LEDs are actually used, "two-color LEDs" are used in industrial products.Also called (2C-LED)[Source required]..In addition, it is different from the "three-color LED method" that uses three-color LEDs of red, blue, and green with white LEDs.
After that, those equipped with white LEDs, single colors of red, blue, green, and two-color mixed colorsyellow-cyan-マ ゼ ン タ, What is said to be a multi-color LED that displays a total of 7 colors of white in a three-color mixture, and all colors can be displayed with high-brightness red, blue, and green LEDs.フ ル カ ラ ーLED ones have also appeared.Full-color LEDs are becoming mainstream in recent years.Route buses do not have as many display types as railways and do not require many colors, so it was a method that mainly used orange, which does not interfere with traffic while using "3-color LEDs", but in recent years, full-color LEDs have been used. There are some examples of adopting it.
Conventionally, for large-scale vision light emitting elementsCRT,VFD OfThree primary colors of lightElements were used, but with the advancement of blue LEDs, LEDs have been used instead.Compared to other methods, the cost and brightness are superior, and it is becoming more widespread.
LED products such as LED modules are becoming more widespread in store signboards as well, instead of conventional FL fluorescent tubes.The size and weight of signboards and signs have been reduced, and there are few failures and the cost is excellent.
LCD display backlight
The white light emitted by the cold-cathode tubeColor filterColor obtained by transmitting with"Red"-绿-tag), The light emitted by the RGB 3-color light emitting diode has higher color purity.for that reason,Liquid crystal display OfBacklightLight sourceCold cathode tubeBy replacing the color with a light emitting diode, the color reproduction range can be greatly expanded.It also consumes less power.For this reason, it is now commonplace to use LEDs as a liquid crystal backlight source.However, low-cost and highly efficient pseudo-white LEDs are often used, and in this case, the color reproduction range is inferior to that of the wide color gamut type cold cathode fluorescent lamp.In addition, since LEDs are used, unevenness is likely to occur when trying to irradiate a large area.
As an LED backlight for large displays,2004In 11 monthSonyMore liquid crystaltv set"QUALIAIt was put into practical use.It became more popular from 2008, and each manufacturer began to adopt mainly high-end models.LED tvIs generally an LCD TV equipped with an LED backlight. As of 2011, the price is getting lower and it may be adopted by lower models.Area drive compatible models have the advantage that the contrast, which is a weak point of the liquid crystal display, can be greatly expanded by area drive that turns off the LED backlight only in the dark part of the image.In addition, LCD TVs with reduced thickness called ultra-thin,laptopThe LED backlight is also an important factor in making the product thinner.In addition, the edge-type display equipped with an LED backlight consumes less power than a CCFL (fluorescent tube) TV due to the characteristics of the LED.
To be precise, the term "LED display" used to refer to the above-mentioned "LED TV" and all liquid crystal displays equipped with LED backlights.MisuseIs.The backlight of the LCD TV is for emitting light, not for displaying images.Because.LuminouselementSee below for "LED displays" that use LEDs.
Micro LED display
A display that uses ultra-small LEDs as the light emitting element.Compared to liquid crystal displays and displays using organic electroluminescence, it is said to be superior in terms of image quality and longevity.While it is often used in the above-mentioned large-scale visions and street advertisements, it has not been developed much in displays for general household use due to the problem of its implementation cost.
In addition, Sony said,Crystal LED DisplayDeveloped.
For various lighting
With the development of white LEDs that can realize energy saving, high brightness and long life, energy consumption accompanied by heat generation is large.light bulbIt is expected as a new indoor / outdoor lighting material instead (LED lighting).Since the design and light color can be adjusted, more flexible lighting is possible.Currently, products with performance that replaces existing lighting are on the market, such as flashlights, passenger car lamps, light bulb type lighting, spotlights, nightlights, side lighting, etc.Street light,Road lightingProducts using LEDs are appearing one after another.According to a report released in 2011 by the Institute of Energy Economics, Japan, incandescent lamps throughout JapanFluorescent lightIt is estimated that 1 billion kilowatts can be saved per hour as a power saving potential when all of the above are replaced with LED lighting.This is equivalent to about 922% of Japan's total electricity consumption,Nuclear power plant13 units.
The price of "LED bulbs" that can be attached to the sockets of incandescent bulbs, mainly E26 and E17, has dropped significantly due to competition between companies.Considering product life and power consumption, "LED bulbs" are said to be cheaper than incandescent bulbs and compact fluorescent bulbs, but they are still young products and have a nominal life. As, 40000 hours sung by each manufacturerThere are almost no cases where the number of individuals has reached the limit, and it is unknown how the repeated lighting and extinguishing and continuous lighting affect the deterioration related to the lifespan.
Brightness and irradiation range differ depending on the model number of the "LED bulb".There are a wide variety of types, such as those that claim to be closer to a light bulb, those that claim a wide light distribution, and those that claim only downward.Among them, 12 manufacturers said that the brightness was inappropriately displayed (good misidentification) if it was brighter than the actual brightness.Against20126,Consumer Affairs Agency Freebie display methodMeasures order based onWas done.As a result, there was a movement to create a brightness standard for "LED light bulbs," and the Japan Light Bulb Industry Association, an industry group, determined how many watts of light bulbs would correspond to when replaced with light bulbs. Lumen) was unified as a standard for brightness display...As a result, each member company's light bulb product had to match the standard lumen and the actual lumen, which can be displayed as the equivalent of several watts of the light bulb, and improper labeling was eliminated.However, the products of non-member companies are often sold via the Internet, and there are still many cases where inappropriate labeling continues.
A straight tube fluorescent lamp (FL40W type, etc.) with the same shape and mouthpiece (T8: G13) has also been released, and with the drop in LED chip prices, a slight cost advantage is emerging.However, unlike "LED bulbs", which have a sharp drop in price and a large difference in power consumption from light bulbs, straight tube fluorescent lamp type LEDs originally compete with low power consumption fluorescent lamps, resulting in a difference in power consumption. There are few, and the price is high.There are two types of covers, transparent and milky white. It is appropriate to choose transparent if you want to emphasize the illuminance directly underneath, and milky white if you want a wide irradiation angle (some have a maximum of 2 degrees).Since a single LED element cannot obtain a sufficient luminous flux as a lighting device, multiple LED elements are used according to the purpose of use to ensure illuminance. It is not uncommon for products to use more than 310 LED elements.However, since the weight is heavier than that of fluorescent lamps, there is a risk that the socket cannot withstand the weight and falls, and there are many types in which it is necessary to remove the ballast of the fluorescent lamp fixture.Therefore, major Japanese manufacturers are developing LED units for the fixtures themselves.
As with straight tube fluorescent lamps, ceiling lights that use round fluorescent lamps have a small difference in power consumption and are expensive due to competition with low power consumption fluorescent lamps.
Surface mount There are examples of lighting fixtures that use (SMD) type LEDs, which are called "SMD lights" and are sold in different ways, but they are essentially the same as LEDs.
As a light source for automobile lights, it started in the late 2000s.tail lampBegan to be used as a light source for.Tail lamps are frequently used because they are used to warn the following vehicle of brake operation and to appeal the existence of the vehicle when driving at night, and while the life is short due to sudden power supply and heat generation, the lamp burnout is likely to lead to an accident Therefore, long-life LEDs are suitable.Incandescent lighting takes a long time to generate heat, which causes a time lag from braking to lighting, which can be one of the causes of accidents, but LEDs have a very small time lag.
Initially, there was no example of using LEDs for headlights due to insufficient light, but the 2007th generation released in May 5.LS600hToKoito ManufacturingIs equipped with the world's first LED headlamp (for applications other than railways) jointly developed by Nichia Corporation... The LED headlamps of the LS600h did not have enough light with one LED lamp, and three LED lamps were used as low beams.After that, the amount of light per LED lamp increased, and the third generation released in 1Lexus ISNow you can use it as a low beam with one LED lamp. LED headlamps consume less power and have more light than HID., Is being adopted by each automobile manufacturer.
オ ー ト バ イKo-zaru cubs (made by CK Design) have been using it for blinkers, tail lamps, and stop lamps since 2003.Since it is a small motorcycle, the battery loading capacity is limited, so it was adopted from the viewpoint of power consumption.This is the first case in Japan.While verifying the recent improvement in LED performance, we are researching the application of LEDs to headlights.[Who?]..Honda announced on March 2014, 3, and released it on the 14th of the same month as the first general commercial motorcycle to be installed.CB1300It was officially adopted from the 54 model of Super Bol d'Or (model SC2014).
Around 2020, many LED lights are on the market as so-called after-parts for both automobiles and motorcycles.these are
- The lamp housing remains the same and takes the form of a conversion kit from traditional incandescent bulbs and HID lamps.
- Whole lamp housingASSYWhat to replace.So-calledEuro tailIt also has a strong side as a dress-up part due to changes to the design that incorporates the latest trends.
- It takes the form of a general-purpose assembly that does not specify the vehicle type.Fog lights for motorcycles and additions,DRL,High mount stop lampEtc. can be seen.
There is a form called.
BicycleThe LED penetration rate of lamps is very high compared to that of automobiles.Since the force of pedaling to move the generator is directly linked to the ride comfort, the use of LEDs with low power consumption provides a light ride comfort.In addition, since the power consumption is low, the load due to lighting is greatly reduced by using a non-contact type generator.In addition, even if it is battery-powered, it has the advantage that the battery lasts longer because it consumes less power.CheapILight carLight bulbs are still the mainstream in such cases,HubDynamoOf expressionAuto lightHas been widely adopted in.In addition, it is often applied to recognition lights and tail lights that are conscious of visibility from other bicycles and automobiles, rather than serving as headlights.
As a lighting fixture for stage production
Stage lighting fixtures equipped with high-brightness LEDs are on sale from manufacturers.By installing high-brightness LEDs of red, green, blue, (amber, cyan, lime) and 3 to 6 colors, the following advantages can be obtained compared to stage lighting using general filaments.
- Power consumption is overwhelmingly low.
- Many colors can be expressed with one lighting.Gradation is also possible with seamless switching.
These are gradually changing from the stage lighting of halogenated incandescent light bulbs, and are being put to practical use in concerts and live performances including the stage.
Solar lights for garten
Lamps that use solar panels and rechargeable batteries have become widespread, and each home improvement store has a dedicated sales floor.
Photosensitive light source inside an electrophotographic printer
Common as an electrophotographic printerLaser printerIt is,laserYou can change the light output directly,liquid crystalLight whose intensity is modulated by a shutter is reflected by a rotating (polygon mirror).scanningBy doing so, scanning lines are created on the photosensitive drum.High precision is required for the optical system, and it is necessary to secure a running distance of a certain level or more due to the structure, and it is difficult to reduce the size and price of the printer.
The solution was to use an LED array head.LED printerIs.Thousands-tens of thousands of finely processed LEDs arranged in a straight line[Note 4], Photosensitive writing is performed with the LED corresponding to 1 dot 1 dot of the latent image on the photosensitive drum.The mechanical drive system (polygon mirror) is no longer required, and the optical system requires only a simple condensing lens to improve reliability, reduce costs, and reduce the size of equipment.However, the main scanning resolution is limited by the degree of integration of the head, it is necessary to correct variations between elements, and because the drum and LED array are very close, scattered toner adheres and the quality stability of the output is lacking. It also has drawbacks.
Light source for optical communication
Taking advantage of the characteristic that the optical output responds at high speed to changes in the drive current, infrared rays for home appliances, etc.リ モ コ ン,TOSlinkStarting withOptical fiberCommunication signal transmitter, alsoPhoto couplerInfrared LEDs are widely used as the internal light source.
Light source for sensor
Infrared light emitting LED detects the presence or absence of an object in combination with a phototransistor or the like.Photo-interrupterIt is used as a component of a photo reflector or the like.
Light source for model making / modification
modelSmall size that was once used as a lighting light source for price reductionlight bulbHas come to be used as an alternative to.Due to the limitation of light color, it was mainly used for red light in the past, but with the development of yellow and white LEDs, headlights and indoorsFluorescent lightIt is also possible to reproduce the white light of.Furthermore, with regard to the reproduction of incandescent lamps, the development of light bulb color (pale orange) LEDs has made it possible to reproduce the actual light color even in places that were difficult with actual light bulbs due to size and heat generation.In particular, the space for incorporating the lighting mechanism is limited, and the membersABS,polystyreneIn some cases, it was disadvantageous in terms of heat generation of the light bulb, such as being made of resin.N gaugeCentered onRailway modelIn the case of, the shift from the normal lens type to the chip type greatly contributed to the reproduction of the actual feeling by downsizing the structure, which made it possible to commercialize the vehicle model that was difficult to commercialize due to the headlight structure of the actual vehicle in the past. It was realized.In terms of cost, even if it is more expensive than using conventional light bulbs, it has been welcomed by users due to the realization of a realistic model, and although the consumption as a field is small, it is adopted prior to use in practical lighting equipment. Has been done.Other model applications include detail-up parts for car models.Four wheel drive miniTamiya genuine custom parts forThere are LED kits for remodeling.
As a substitute for electronic flashes and reflectors
With a camera (similar to a digital camera), the exposure is exposed when shooting in the dark, close-up shooting, or portrait shooting.LatitudeIn the sense of aligningElectronic flash(Flash) andReflectorIn general flash photography, the light is applied instantaneously, so it is difficult for the photographer or subject to imagine the finish of the photograph.The reflector has a natural lighting effect, but has the disadvantage that it is bulky and difficult to transport when moving.The photo lightIncandescent light bulbSince many of them use the above principle, the heat radiation for the lighting efficiency is large, and there are many cases where the subject is not preferable as a lighting fixture when the subject dislikes heat.Also, the equipment that you carry for shooting outside the studio is virtuallyClip-on flashLimited to. The LED array type light can be driven by a battery, can obtain the necessary and sufficient amount of light as an illumination light source, and can be used for a relatively long time, so it is expected to be widely used as a lighting fixture for photography in the future. ..
2013Since around that time, LED lights for photography, in which white LEDs are laid out in an array, have become widespread as lighting fixtures mainly on the Internet, with China as the country of origin.
As a substitute for candles and lights
ろ う そ くLED lighting fixtures that resemble are also manufactured and sold.burnWithout worrying about火災There is a merit that the risk of is low.In combination with sensors and computers, surroundingssoundTo sense and move the light,WindTechnology has also been developed to reproduce the flicker of flames caused by.
As a substitute for other electronic components
As a substitute for Zener diodes
Commonly used as a reference voltage source in electronic circuitsZener diode TheAvalanche surrenderBecause it uses the phenomenon, the output voltage is slightlynoiseWill be generated.NormallyFilter circuitDesigned to sufficiently attenuate noise,Operational amplifierThere are cases where LEDs driven with a constant current are used in pursuit of a "reference voltage source that does not generate noise in the first place", such as when assembling discretely.
As a substitute for small signal diodes
Water can be sterilized by emitting deep ultraviolet rays..
- ^ The current that flows when a forward voltage is applied to a circuit element that has a directional current flow, such as a diode.
- ^ British: organic light-LED diodes
- ^ Toshiba (high color rendering) In the example of beautiful color540lm / 8.8W = 63lm / WThe lamp efficiency of the high color rendering LED is not so high.
- ^ Thousands to tens of thousands can be lined up in one process like ordinary semiconductor processing.
- ^ “The life and times of the LED — a 100-year history”. The Optoelectronics Research Center, University of Southampton. (April 2007) 2012/9/4Browse.
- ^ US Patent 3293513, "Semiconductor Radiant Diode", James R. Biard and Gary Pittman, Filed on Aug. 8th, 1962, Issued on Dec. 20th, 1966.
- ^ “Inventor of Long-Lasting, Low-Heat Light Source Awarded $ 500,000 Lemelson-MIT Prize for Invention”. Massachusetts Institute of Technology. Washington, DC. (April 2004, 4) 2011/12/21Browse. [Broken link]
- ^ The story that follows Edison: GE engineer Nick Holonyak's LED invention 50 years ago(GE imagination at work / Original (English): Published August 2012, 8)
- ^ Blue LED proceedings, full settlement Toyoda Gosei Co., Ltd., Nichia Corporation
- ^ Nichia NV3W470A
- ^ Nichia LED Technical Data (PDF)
- ^ Z-Power LED P7 Series --Seoul Semiconductor Co., Ltd.
- ^ ""Angry at the rotten judiciary" Professor Nakamura returns to Japan and criticizes”. Kyodo News (January 2005, 1). Retrieved January 12, 2012.
- ^ 3 Nobel Prize in Physics for 2014 Japanese nippon.com October 2014, 10
- ^ Why Blue LEDs Deserve Nobel Prize WIRED October 2014, 10
- ^ "<Research Part 2> Research on color rendering index evaluation methods for lighting light sources (including LEDs)”. Japan Color Research Institute. 2015/10/19Browse.
- ^ "Toyoda Gosei / News / Press Release "Development and Sales of High Color Rendering High Power White LED Lamps"”. Toyoda Gosei Co., Ltd. (October 2003, 10). Retrieved January 7, 2012.
- ^ Product example
- ^ JR West Japan 221 seriesな ど
- ^ Structure and how to make a liquid crystal display
- ^ "Following LCD and OLED !? What is the third new generation TV "Micro LED"? --Price.com Magazine”(Japanese). kakaku.com. 2019/6/2Browse.
- ^ "Succeeded in developing the world's first 1.1-inch QVGA high-brightness LED display | 2009 | News Release Information | OKI Data”. Oki Data Corporation (November 2009, 11). Retrieved January 26, 2012.
- ^ http://eneken.ieej.or.jp/data/3862.pdf
- ^ Example Panasonic LED bulb
- ^ (PDF)
- ^ (PDF)
- ^ (PDF)
- ^ (PDF)
- ^ Next-generation headlights will be LEDs! All About
- ^ The LED headlamps of the new "Lexus IS" are the 4th generation, and the power consumption is less than half that of the 1st generation.
- ^ Product example (Tamiya genuine):GP.384 N-03 / T-03 Bumperless LED (red) unit
In the past, there were products with only LEDs (Red: No.081 Green: No.224), but as of March 2017, they are out of print.
- ^ LED lighting that fluctuates in the wind Reproduces the atmosphere of Japanese candles Developed by Kanagawa Institute of Technology, etc."Nikkei" evening edition March 2018, 3 (page 31)
- ^ Sankei News [Sterilizing water] Deep UV LED "Future Light"
- 10000 isComposite numberAnddivisor The 1, 2, 4, 5, 8, 10, 16, 20, 25, 40, 50, 80, 100, 125, 200, 250, 400, 500, 625, 1000, 1250, 2000, 2500, 5000, 10000.
- 100 thSquare numberIs. The previous one is 1, the next is10201.
- 10000 = (2 x 50)2
- 10000 = (4 x 25)2
- 10000 = (5 x 20)2
- The sum of two numbers separated without changing the order of their own numberssquareIs the 7th number to be itself. The previous one is 1 and the next one is 9801. (Online Integer Sequence DictionarySequence of A102766)
- = 10000 104
- 10 th4 multiplier(Double square number). The previous one6561,next14641. (Online Integer Sequence DictionarySequence of A000583)
- n = 4 10n When you see the value of1000,next100000.
- 10000 = (2 x 5)4
- 10000 = 10 × 103
- 1 = 0.0001
- 1538 thHarshad numberIs. The previous one was 1 and the next was 9990.
- There are two numbers where the sum of divisors is 10000. (2, 8743) This is the 9481th number that can be represented by two sums of divisors. The previous one is 2, the next is 455.
Other things related to 10000
- 10000'sprefix : Milia(Greek language）
- JapaneseThen, when expressing a large number, every 10000 timesnumeralchangeManshinIs used.
- Betting ticket
- It is used to mean "there are many".
- 2018Current,Bank of Japan notesThe maximum amount ofXNUMX yen bill.
- At the railway company10000 seriesMany companies own vehicles of the type.
- In Japan and other countries, 10000 is the unit delimiter. Ten thousand,Billion,Trillion,Kyoto,垓, …… (→Numeral system）
- (10000 / 1) is 1 yarn()
- 10000m race,10000 metersBothAthleticsOne of the events.
- 10000 m² = 1 ha
- 10000 cm2 = 1 m²
- J League(J1)10000 goals in total TheGamba Osaka OfMaeda MasafumiWas achieved.
- Asteroid numberNo. 10000小 惑星Is named after the Greek word 10000MyriostosIt is named.
An integer between 10001 and 19999
An integer between 10001 and 11000
- 10007 - Safety prime
- 10033 --Serial program by videoLonelygirlfifteenFictitious character
- 10061 - Sophie Germain prime
- 10079 --Safe prime,Super prime
- 10080 - Advanced composite number
- 10091 -Sophie Germain prime
- 10103 -Safety prime
- 10163 --Sophie Germain prime and safe prime (29th)
- 10201 - PalindromeSquare number.. What N > 2 Against N SystemEven if it is written as 10201, 10201 is always a palindromic square number. this is To hold
- 10206 - Five-sided pyramid
- 10223 - Sierpinski problemAtSeventeen or BustThe smallest of the 6 numbers discovered by the project
- 10253 -Sophie Germain prime
- 10271 -Sophie Germain prime
- 10301 - Decimal systemInPalindrome
- 10313 -Sophie Germain prime
- 10331 -Sophie Germain prime
- 10333 - HexagramPrime number
- 10343 -Safety prime
- 10404 = 1022 , What N > 4 Against N SystemEven if it is written as 10404, 10404 is alwaysSquare numberBecomes To hold
- 10416 - Number of quadrangular pyramids
- 10425 - 
- 10430 - Weird number
- 10463 -Safety prime
- 10501 --Palindromic primes in decimal
- 10529 -Sophie Germain prime
- 10559 -Safety prime, super prime
- 10570 --Wird number
- 10585 - Carmichael number
- 10589 -Sophie Germain prime, super prime
- 10601 --Palindromic prime
- 10607 -Safety prime
- 10609 - Tribonacci number, What N > 9 Against N Even if it is written as 10609 in base, 10609 is always a square number. To hold
- 10613 -Sophie Germain prime
- 10646 - ISO 10646
- 10660 - Number of triangular pyramids
- 10667 -Safety prime
- 10671 - Tetra Natch number
- 10691 -Sophie Germain prime
- 10709 -Sophie Germain prime
- 10733 -Sophie Germain prime
- 10744 - Fraternity(10744, 10856)
- 10781 -Sophie Germain prime
- 10792 --Wird number
- 10799 --Sophie Germain prime and safe prime (30th)
- 10816 = 1042
- 10837 --Prime number of six-pointed stars
- 10856 --Amicable numbers (10744, 10856)
- 10883 --Sophie Germain prime and safe prime (31th)
- 10887 --70 from the beginning素 数 Of和
- 10946 - Fibonacci number,Markov number
- 10989 ――The number that is reversed when multiplied by 9(10989 x 9 = 98901)
- 10990 --Wird number
An integer between 11001 and 12000
- 11003 -Safety prime
- 11025 = 1052 = 13 + 23 + 33 +… + 143 , The sum of the cubes of integers from 1 to 14
- 11171 -Sophie Germain prime
- 11279 -Safety prime
- 11311 --Palindromic primes in decimal
- 11321 -Sophie Germain prime
- 11353 - HexagramPrime number
- 11368 -Five-sided pyramid number
- 11369 -Sophie Germain prime, super prime
- 11393 -Sophie Germain prime
- 11410 --Wird number
- 11411 --Palindromic primes in decimal
- 11423 -Safety prime
- 11440 -Number of pyramids
- 11471 -Sophie Germain prime
- 11480 -Number of triangular pyramids
- 11483 -Safety prime
- 11519 -Sophie Germain prime
- 11549 -Sophie Germain prime
- 11579 -Sophie Germain prime
- 11664 = 1082, 24× 36,Prime factorizationShape 2i × 3j , The previous one is 1, the next is 10368.
- 11690 --Wird number
- 11699 --Sophie Germain prime and safe prime (32th)
- 11726 -Octahedron number
- 11783 -Sophie Germain prime
- 11801 -Sophie Germain prime
- 11807 -Safety prime
- 11813 -Sophie Germain prime
- 11826 --In decimal, its square does not use 2Pandigital numberMinimum number to be(118262 = 139854276)
- 11831 -Sophie Germain prime
- 11909 -Sophie Germain prime, super prime
An integer between 12001 and 13000
- 12011 -Sophie Germain prime
- 12041 -Sophie Germain prime
- 12101 -Sophie Germain prime
- 12107 -Safety prime
- 12110 --Wird number
- 12119 -Sophie Germain prime
- 12203 --Sophie Germain prime and safe prime (33rd), super prime
- 12227 -Safety prime
- 12263 --Sophie Germain prime and safe prime (34th)
- 12285 --Amicable numbers (12285, 14595)
- 12287 - 
- 12321 = 1112, Palindromic square number.. What N > 3 Against N SystemEven if it is written as 12321 by, 12321 is always a palindromic square number. this is Because it holds.
- 12329 -Sophie Germain prime
- 12341 -Number of triangular pyramids
- 12347 -Safety prime
- 12421 --Palindromic primes in decimal, Super prime
- 12527 -Safety prime
- 12529 -Number of pyramids
- 12530 --Wird number
- 12539 -Safety prime
- 12615 -Five-sided pyramid number
- 12647 -Safety prime, super prime
- 12653 -Sophie Germain prime
- 12659 -Safety prime
- 12670 --Wird number
- 12671 -Sophie Germain prime
- 12718 -Sum of 75 prime numbers from the beginning
- 12721 --Palindromic primes in decimal
- 12726 - Ruth-Aaron Pair
- 12758 --Maximum number that cannot be represented as the sum of different cubes
- 12769 = 1132, What N > 7 Against N SystemEven if it is written as 12769 by, 12769 is always a palindromic square number. this is Because it holds.
- 12791 -Sophie Germain prime
- 12821 --Sophie Germain prime, palindromic prime in decimal
- 12899 --Sophie Germain prime and safe prime (35th)
- 12923 -Sophie Germain prime
- 12959 -Sophie Germain prime
- 12983 -Safety prime
An integer between 13001 and 14000
- 13001 --Sophie Germain prime number, 13thQuadruplet prime (13001, 13003, 13007, 13009)
- 13043 -Safety prime
- 13049 -Sophie Germain prime
- 13103 -Safety prime
- 13127 -Safety prime
- 13131 -Octahedron number
- 13163 -Safety prime
- 13229 -Sophie Germain prime
- 13244 -Number of triangular pyramids
- 13313 -Sophie Germain prime
- 13331 --Palindromic primes in decimal, Super prime
- 13370 --Wird number
- 13451 -Sophie Germain prime
- 13463 -Sophie Germain prime
- 13510 --Wird number
- 13523 -Safety prime
- 13553 -Sophie Germain prime
- 13579 - odd numberThe number of lines side by side.
- 13619 -Sophie Germain prime
- 13649 -Sophie Germain prime, super prime
- 13685 -Number of pyramids
- 13763 -Sophie Germain prime
- 13790 --Wird number
- 13799 -Safety prime
- 13831 --Palindromic primes in decimal
- 13860 - Pell number
- 13883 -Sophie Germain prime
- 13901 -Sophie Germain prime
- 13913 -Sophie Germain prime
- 13930 --Wird number
- 13931 --Palindromic primes in decimal
- 13950 -Five-sided pyramid number
- 13967 -Safety prime
An integer between 14001 and 15000
- 14009 -Sophie Germain prime
- 14081 -Sophie Germain prime
- 14087 -Safety prime
- 14153 -Sophie Germain prime
- 14159 --Sophie Germain prime and safe prime (36th)
- 14190 -Number of triangular pyramids
- 14200 - n = 12n-Queen problemNumber of solutions
- 14207 -Safety prime
- 14243 -Safety prime
- 14249 -Sophie Germain prime
- 14303 --Sophie Germain prime and safe prime (37th)
- 14321 -Sophie Germain prime
- 14341 --Palindromic primes in decimal
- 14387 -Safety prime
- 14400 = 1202 = 13 + 23 + 33 +… + 153, The sum of the cubes of integers from 1 to 15
- 14423 -Safety prime
- 14489 -Sophie Germain prime
- 14561 -Sophie Germain prime
- 14621 -Sophie Germain prime
- 14641 = 114 ,Quartet = 1212, Palindromic square number, What N > 6 Against N Even if it is written as 14641 in the base system, 14641 is always a fourth power. this is To hold
- 14644 -Octahedron number
- 14669 -Sophie Germain prime
- 14697 -Sum of 80 prime numbers from the beginning
- 14699 --Sophie Germain prime and safe prime (38th)
- 14701 --Markov number
- 14741 --Sophie Germain prime, palindromic prime in decimal
- 14770 --Wird number
- 14783 -Sophie Germain prime, super prime
- 14595 --Amicable numbers (12285, 14595)
- 14831 -Sophie Germain prime
- 14867 -Safety prime
- 14879 -Sophie Germain prime
- 14884 = 1222, Any N > 8 N Even if 14884 is written in base, this 14884 is always a square number. that is Because
- 14910 -Number of pyramids
- 14939 -Sophie Germain prime
An integer between 15001 and 16000
- 15083 -Safety prime
- 15101 -Sophie Germain prime
- 15120 -Advanced composite number
- 15127 - Lyca number
- 15161 -Sophie Germain prime
- 15173 -Sophie Germain prime
- 15180 -Number of triangular pyramids
- 15233 -Sophie Germain prime
- 15269 -Sophie Germain prime
- 15287 -Safety prime
- 15299 -Safety prime
- 15376 -Five-sided pyramid number
- 15383 -Safety prime
- 15387 - Zeiser number
- 15401 -Sophie Germain prime
- 15451 --Palindromic primes in decimal
- 15511 - Motzkin number
- 15551 --Palindromic primes in decimal
- 15569 -Sophie Germain prime
- 15610 --Wird number
- 15625 = 56 = 253 = 1252 , Sixth power, Cube . twenty fournWhen I saw it3125Next is 78125.n6When I saw it4096Next is 46656.
- 15641, 15643, 15647, 15649 ――14th prime quadruplet
- 15647 -Safety prime
- 15683 -Safety prime
- 15731, 15733, 15737, 15739 ――15th prime quadruplet
- 15767 -Safety prime
- 15773 -Sophie Germain prime
- 15791 -Sophie Germain prime
- 15803 --Sophie Germain prime and safe prime (39th)
- 15841 --Carmichael number
- 15890 --Wird number
- 15923 -Sophie Germain prime
An integer between 16001 and 17000
- 16001 -Sophie Germain prime
- 16030 --Wird number
- 16061 --Palindromic primes in decimal
- 16061, 16063, 16067, 16069 ――16th prime quadruplet
- 16091 -Sophie Germain prime
- 16127 - Emmap
- 16139 -Safety prime
- 16187 -Safety prime
- 16206 -Number of pyramids
- 16223 -Safety prime
- 16253 -Sophie Germain prime
- 16269 -Octahedron number
- 16301 -Sophie Germain prime
- 16310 --Wird number
- 16361 --Palindromic primes in decimal
- 16384 = 214 
- 16421 -Sophie Germain prime
- 16447 - Friedman number (-1 + 64 + 47)
- 16487 -Safety prime
- 16493 -Sophie Germain prime
- 16547 -Safety prime
- 16553 -Sophie Germain prime
- 16561 --Palindromic primes in decimal
- 16661 --Palindromic primes in decimal
- 16673 -Sophie Germain prime
- 16730 --Wird number
- 16796 - Catalan number
- 16807 = 75 
- 16811 -Sophie Germain prime
- 16823 -Sophie Germain prime
- 16840 -Sum of 85 prime numbers from the beginning
- 16843 -The smallestWolstenholme prime
- 16870 --Wird number
- 16883 -Sophie Germain prime
- 16896 -Five-sided pyramid number
- 16900 <p>2019<p>2, What N > 9 Against N SystemEven if it is written as 16900, 16900 is always a square number. this is To hold
- 16931 -Sophie Germain prime
An integer between 17001 and 18000
- 17027 -Safety prime
- 17159 -Sophie Germain prime
- 17163 --Maximum number that is not the sum of the squares of different prime numbers
- 17183 -Sophie Germain prime
- 17272 --Wird number
- 17291 -Sophie Germain prime
- 17296 --Amicable numbers (17296, 18416)
- 17327 -Safety prime
- 17333 -Sophie Germain prime
- 17344 --First definitionCapreca number
- 17351 -Sophie Germain prime
- 17387 -Safety prime
- 17471 --Palindromic primes in decimal
- 17483 -Safety prime
- 17570 --Wird number
- 17575 -Number of pyramids
- 17576 = 263
- 17579 -Sophie Germain prime
- 17669 -Sophie Germain prime
- 17681 -Sophie Germain prime
- 17711 -Fibonacci number
- 17903 -Safety prime
- 17939 --Sophie Germain prime and safe prime (40th)
- 17971 --Palindromic primes in decimal
- 17981 -Sophie Germain prime
- 17990 --Wird number
An integer between 18001 and 19000
- 18010 -Octahedron number
- 18041 --Sophie Germain prime, 17th prime quadruplet (18041, 18043, 18047, 18049)
- 18059 -Safety prime
- 18119 -Safety prime
- 18131 -Sophie Germain prime
- 18149 -Sophie Germain prime
- 18181 --Palindromic primes in decimal
- 18191 -Sophie Germain prime
- 18225 = 1352 , Friedman number (81 x 225)
- 18233 -Sophie Germain prime
- 18341 -Sophie Germain prime
- 18410 --Wird number
- 18416 --Amicable numbers (17296, 18416)
- 18443 --Sophie Germain prime and safe prime (41th)
- 18461 -Sophie Germain prime
- 18481 --Palindromic primes in decimal
- 18496 = 13 + 23 + 33 +… + 163 , The sum of the cubes of integers from 1 to 16
- 18513 -Five-sided pyramid number
- 18587 -Safety prime
- 18600 - Harmonic number
- 18620 --Harmonic number
- 18731 -Sophie Germain prime
- 18743 -Safety prime
- 18773 -Sophie Germain prime
- 18803 -Sophie Germain prime
- 18830 --Wird number
- 18839 -Safety prime
- 18899 -Sophie Germain prime
- 18911, 18913, 18917, 18919 ――18th prime quadruplet
- 18947 -Safety prime
- 18959 -Safety prime
- 18970 --Wird number
An integer between 19001 and 19999
- 19019 -Number of pyramids
- 19079 -Safety prime
- 19113 -Sum of 90 prime numbers from the beginning
- 19163 -Sophie Germain prime
- 19259 -Safety prime
- 19301 -Sophie Germain prime
- 19319 -Sophie Germain prime
- 19373 -Sophie Germain prime
- 19379 -Safety prime
- 19390 --Wird number
- 19391 --Sophie Germain prime, palindromic prime in decimal
- 19421, 19423, 19427, 19429 ――19th prime quadruplet
- 19433 -Sophie Germain prime
- 19513 --Tribonatch number
- 19553 -Sophie Germain prime
- 19559 -Sophie Germain prime
- 19583 -Safety prime
- 19600 = 1402, Tetrahedral number
- 19609 - Prime gapIs the smallest prime number greater than 50 (19661-19609 = 52)
- 19661 -Sophie Germain prime
- 19670 --Wird number
- 19683 = 39 = 273 , Cube number .Ternary systemAt 1000000000(3),NonaryAt 30000(9).
- 19709 -Sophie Germain prime
- 19751 -Sophie Germain prime
- 19871 -Octahedron number
- 19889 -Sophie Germain prime
- 19891 --Palindromic primes in decimal
- 19913 -Sophie Germain prime
- 19919 -Sophie Germain prime
- 19991 --Sophie Germain prime, palindromic prime in decimal
- ^ a b c A002779
- ^ a b c d e f g A002411
- ^ a b c d e f g h i j k l m n o p q r s t u v A002385
- ^ a b c A083577
- ^ a b c d e f g h A000330
- ^ a b c d e f A005900
- ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab A006037
- ^ a b A002997
- ^ a b A000073
- ^ a b c d e f A000292
- ^ A000078
- ^ a b c d e f A063990
- ^ a b A000045
- ^ a b A002559
- ^ A001232
- ^ a b c A000537
- ^ A071519
- ^ A055010
- ^ A000129
- ^ A000583
- ^ A001020
- ^ A051015
- ^ A001006
- ^ A000351
- ^ A001014
- ^ a b A000578
- ^ A000079
- ^ A000108
- ^ A000584
- ^ A000420
- ^ Higgins, Peter (2008). Number Story: From Counting to Cryptography. New York: Copernicus. P. 61. ISBN 978-1-84800-000-1
- ^ A006886
- ^ Higgins, ibid.
- ^ a b A001599
- ^ A000244
- ^ A001017