Thursday, September 26, 2013

Led lamps and theory



LED light emitting structure and principle Many experts have most of a century ago, the semiconductor material can establish light with the basic knowledge, the initial commercial diode earned in 1960. LED is a English light emitting diode (LED) acronym, with its basic structure works as a area of electroluminescent semiconductor materials, included into a wire rack, thereafter sealed with epoxy resin around, protect the interior core wire effect, so LED's seismic performance. The core including the light-emitting diode may be a p-type semiconductor and n-type semiconductor chip formed inside the p-type semiconductor and n-type semiconductor you will find a transition between, the pn junction. Using semiconductor materials, PN junction, the injection of minority carrier and majority carrier recombination over time to here we are at those to the species of light energy released, which convert light energy towards a utility source. PN junction reverse voltage, minority carrier injection is, it isn't necessarily light. This using of principle of injection electroluminescence diodes called LEDs produced, known as LED. Should it be in condition right after the positive (that ends utilizing a positive voltage), current flows among the cathode LED anode, the semiconductor crystal surrounding the issue from a ultraviolet to infrared light of diverse colors of intensity and current.

2, LED light characteristics 1. Voltage: LED using low-voltage energy, power voltage between 6-24V, vary in keeping with product, so that it is safer than using hollywood energy, people who public. 2. Effectiveness: eating of high efficiency than incandescent light with 80% reduction 3. Applicability: small, miniscule print of each one LED unit is 3-5mm square, it is typically fabricated into various shapes while using the devices, and volatile environment for 4. Stability: 100,000 hours, lights fades to 50% on the initial 5. Response time: the incandescent millisecond response time, Led lighting nanosecond response time 6. Across the environmental pollution: no harmful metal mercury 7. Color: you might modify the current color, light-emitting diodes by chemical modification ways to easily adjust this content band structure and band gap, to achieve in multi-color light orange red Huanglv Lan. Similar to the small current should the red LED, making the current increase, becomes orange, yellow, after which you can to green

8. Price: LED's are costly, as compared to incandescent lamps, some LED's price around the price which has an incandescent lamp rather, each signal usually require of the previous 300 to 500 diodes. 3, monochromatic LED types and history The original use of principles of semiconductor PN junction light-emitting LED light source crafted from 60 entered early Twentieth century. Martial arts could be used GaAsP, hair red ( p = 650nm), the drive current of 20 mA, the luminous flux of just some lumens per thousand, the related luminous efficiency around 0.1 lumens / watt. Mid-70s, enhancing popular features of In and N, to earn green LED ( p = 555nm), yellow ( p = 590nm) and orange ( p = 610nm), optical efficiency is furthermore increased to just one lumen / watt. To the early 80s, appeared from the LED light GaAlAs build the red LED light efficiency of 10 lumens / watt. The primary 90s, hair, red and yellow of GaAlInP and hair green, blue GaInN developed two new materials to make LED light effect was greatly improved. In 2000, hmo's includes LED in red and orange zone ( p = 615nm) light efficiency to 100 lm / W, which made saving money LED in the area ( p = 530nm) light efficiency can reach 50 lm / watts. Fourth, the effective use of monochromatic LED Initially used as instruments of instruction LED light source, then numerous light-colored LED in traffic lights and larger screens with the trusted and produced good economic and social benefits. To 12-inch red traffic lights, for example, are already employed for the states extended life, low-light 140-watt incandescent effective because light, celebrate 2000 Lumens of white. The red filter, the optical reduction in 90%, only 200 lumens of red light. Making the fresh design, Lumileds has utilized a red LED light source 18, including circuit losses, together with a total power 14 watts of can create similar effect. Automotive Led lamps can also be important components of light application. In 1987, China come to install high car brake lights, LED response as fast (nanosecond), are often as soon as possible and so the trailing vehicle drivers know that driving performance and reducing rear-end accident. In addition, Led lighting around the outdoor red, green, blue full-color display, mini flashlight key ring have been completely elements of application. Fifth, improvement white LED For general lighting, the white light that people need. 1998 white light LED developed. This is a GaN LED chip and yttrium aluminum garnet (YAG) made package together. GaN chip of blue ( p = 465nm, Wd = 30nm), produced from high-temperature sintering of YAG phosphor containing Ce3 + excited right this moment blue light following yellow emission peak 550nm. Blue LED substrate established with the reflective cavity bowl, cover along with a comprehensive forensics education YAG thin layer of resin, about 200-500nm. Issued blue LED substrate partially phosphor absorbed, but a majority of blue when mixed with yellow phosphor issued, may be too white. Now, for any InGaN / YAG white LED, YAG phosphor by changing mit composition and adjust the thickness of your phosphor layer, available colors and color temperature 3500-10000K white. about author: I am a competent editor from International Trade Community, and my job is actually to push a cost-free traffic generation online trade platform. http://www.xpshou.com/ have lots of the info on ribbon dog collars , live koi fish the pet visit!

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