Wednesday, September 25, 2013

LED lights and theory



LED light emitting structure and principle It has been most century ago, the semiconductor material can establish light along with the basic knowledge, the best commercial diode earned in 1960. LED may be a English light emitting diode (LED) acronym, along with its basic structure is actually a part of electroluminescent semiconductor materials, included into a wire rack, following sealed with epoxy resin around, protect the inner core wire effect, so LED's seismic performance. The core maybe there light-emitting diode may be a p-type semiconductor and n-type semiconductor chip formed on the p-type semiconductor and n-type semiconductor there is a transition between, the pn junction. Using semiconductor materials, PN junction, the injection of minority carrier and majority carrier recombination overall to here we are at the criminals to the sort of light energy released, which convert light energy directly into a source. PN junction reverse voltage, minority carrier injection is very, it is not necessarily necessarily light. This utilization of principle of injection electroluminescence diodes called LEDs produced, called LED. If at all in condition when the positive (that ends by using a positive voltage), current flows belonging to the cathode LED anode, the semiconductor crystal to the issue from the ultraviolet to infrared light of several colors of intensity and current.

2, LED light characteristics 1. Voltage: LED using low-voltage energy, power voltage between 6-24V, vary according to product, that makes it safer than using hollywood energy, folks that public. 2. Effectiveness: utilization of high efficiency than incandescent light with 80% reduction 3. Applicability: small, small type associated with 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% within the initial 5. Response time: the incandescent millisecond response time, Led lamps nanosecond response time 6. On the environmental pollution: no harmful metal mercury 7. Color: you could potentially change the current color, light-emitting diodes by chemical modification methods to easily adjust your content band structure and band gap, to achieve multi-color light orange red Huanglv Lan. Including the small current when the red LED, along with the current increase, evolves into orange, yellow, after which it to green

8. Price: LED's are pricey, as compared with incandescent lamps, a small number of LED's price within the price utilising an incandescent lamp rather, each signal usually require belonging to the previous 300 to 500 diodes. 3, monochromatic LED types and history The main making use of principles of semiconductor PN junction light-emitting LED source of light constructed from 60 entered early Last century. The fabric are going to be used GaAsP, hair red ( p = 650nm), the drive current of 20 mA, the luminous flux of a few lumens per thousand, the related luminous efficiency around 0.1 lumens / watt. Mid-70s, enhancing attributes of In and N, to earn green LED ( p = 555nm), yellow ( p = 590nm) and orange ( p = 610nm), optical efficiency is in addition increased to 1 lumen / watt. For that early 80s, appeared in the LED light source GaAlAs make the red LED light efficiency of 10 lumens / watt. The very first 90s, hair, red and yellow of GaAlInP and hair green, blue GaInN developed two new mats 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 community ( p = 530nm) light efficiency can reach 50 lm / watts. Fourth, the utilization of monochromatic LED Initially used as instruments of instruction LED source of light, then numerous light-colored LED in traffic lights and greater screens in the trusted and produced good economic and social benefits. To 12-inch red traffic lights, as an example, have been put to use for the us . extended life, low-light 140-watt incandescent effective because light, it creates 2000 Lumens of white. The red filter, the optical loss of 90%, only 200 lumens of sore point. Considering the fresh design, Lumileds has utilized a red LED light 18, including circuit losses, with a total power of 14 watts of can create similar effect. Automotive Led lamps are likewise important issues with light application. In 1987, China continue to install high car brake lights, LED response as quicly (nanosecond), are frequently early so the trailing vehicle drivers be aware that driving performance and reducing rear-end accident. On top of that, Led lighting in the outdoor red, green, blue full-color display, mini flashlight key ring have been completely parts of application. Fifth, improvement white LED For general lighting, the white light that folks need. 1998 white light LED developed. This is often 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 at this moment blue light following yellow emission peak 550nm. Blue LED substrate established during the reflective cavity bowl, cover that features a comprehensive forensics education YAG thin layer of resin, about 200-500nm. Issued blue LED substrate partially phosphor absorbed, however, some blue when put together with yellow phosphor issued, will be too white. Now, for that InGaN / YAG white LED, YAG phosphor by changing mit composition and adjust the thickness of this phosphor layer, available colors and color temperature 3500-10000K white. about author: I'm a competent editor from International Trade Community, and my jobs are actually to push a cost-free marketing strategy online trade platform. http://www.xpshou.com/ have many of the information of ribbon dog collars , live koi fish thanks for visiting visit!

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