About LEDS Strip,you may know
About LEDS Strip,you may know
Miniature These are mostly single-die LEDs used as indicators, and they come in various-sizes from 2 mm to 8 mm, through-hole and surface mount packages. They are usually simple in design, not requiring any separate cooling body. Typical current ratings ranges from around 1 mA to above 20 mA. The small scale sets a natural upper boundary on power consumption due to heat caused by the high current density and need for heat sinking. where to buy cheap LED Strip? Lightereryday is a good choice.
Mid-range Medium power LEDs are often through-hole mounted and used when an output of a few lumen is needed. They sometimes have the diode mounted to four leads (two cathode leads, two anode leads) for better heat conduction and carry an integrated lens. An example of this is the Superflux package, from Philips Lumileds.
These LEDs are most commonly used in light panels, emergency lighting and automotive tail-lights. Due to the larger amount of metal in the LED, they are able to handle higher currents (around 100 mA). The higher current allows for the higher light output required for tail-lights and emergency lighting High power High power LEDs (HPLED) can be driven at currents from hundreds of mA to more than an ampere, compared with the tens of mA for other LEDs. Some can emit over a thousand lumens.
Since overheating is destructive, the HPLEDs must be mounted on a heat sink to allow for heat dissipation. If the heat from a HPLED is not removed, the device will fail in seconds. One HPLED can often replace an incandescent bulb in a torch, or be set in an array to form a powerful LED lamp.
Some well-known HPLEDs in this category are the Lumileds Rebel Led, Osram Opto Semiconductors Golden Dragon and Cree X-lamp.
As of September 2009 some HPLEDs manufactured by Cree Inc. now exceed 105 lm/W (e.g. the XLamp XP-G LED chip emitting Cool White light) and are being sold in lamps intended to replace incandescent, halogen, and even fluorescent lights, as LEDs grow more cost competitive.
LEDs have been developed by Seoul Semiconductor that can operate on AC power without the need for a DC converter. For each half cycle, part of the LED emits light and part is dark, and this is reversed during the next half cycle.
The efficacy of this type of HPLED is typically 40 lm/W. A large number of LED elements in series may be able to operate directly from line voltage. In 2009 Seoul Semiconductor released a high DC voltage capable of being driven from AC power with a simple controlling circuit.
The low power dissipation of these LEDs affords them more flexibility than the original AC LED design. recommend directory: Waterproof IP68 Aluminum Shell SMD 5050 LED Light Bar.
In an organic light emitting diode (OLED), the electroluminescent material comprising the emissive layer of the diode is an organic compound. The organic material is electrically conductive due to the delocalization of pi electrons caused by conjugation over all or part of the molecule, and the material therefore functions as an organic semiconductor.
The organic materials can be small organic molecules in a crystalline phase, or polymers. The potential advantages of OLEDs include thin, low cost displays with a low driving voltage, wide viewing angle and high contrast and colour gamut. Polymer LEDs have the added benefit of printable and flexible displays.
OLEDs have been used to make visual displays for portable electronic devices such as cellphones, digital cameras, and MP3 players while possible future uses include lighting and televisions.
A new method developed by Michael Bowers, a graduate student at Vanderbilt University in Nashville, involves coating a blue LED with quantum dots that glow white in response to the blue light from the LED. This method emits a warm, yellowish-white light similar to that made by incandescent bulbs. Quantum dots are semiconductor nanocrystals that possess unique optical properties.Their emission color can be tuned from the visible throughout the infrared spectrum.
This allows quantum dot LEDs to create almost any color on the CIE diagram. This provides more color options and better color rendering than white LEDs. Quantum dot LEDs are available in the same package types as traditional phosphor based LEDs.
In September 2009 Nanoco Group announced that it has signed a joint development agreement with a major Japanese electronics company under which it will design and develop quantum dots for use in light emitting diodes (LEDs) in liquid crystal display (LCD) televisions.recommend directory: 57cm 30LEDS SMD5050 LED Light Bar. Something about LEDS Strip Cowboy and Native American Decor In Your Abode and Patio South Africa For Travellers A Midsummer's Night Dream Setting Bridesmaid jewelry customs from different countries Iconic Attractions to Visit on Your Mauritius Honeymoon Tour Starting a PhD in Australia as an International student Bangladesh vs South Africa, ICC Cricket World Cup 2011, Live Score Card Check your tyres before you holiday trip Saving money while studying in Australia, a guide for Australians and International students Himachal holiday packages: true glory of nature International students: one of Australia's biggest exports Safety in Australia following attacks on Indian students