Ad
related to: high power led physics calculator
Search results
Results From The WOW.Com Content Network
Typical LED package including thermal management design Thermal animation of a high powered A19 sized LED light bulb, created using high resolution computational fluid dynamics (CFD) analysis software, showing temperature contoured LED heat sink and flow trajectories Thermal animation of a high power density industrial PAR 64 LED downlight heat sink design, created using high resolution CFD ...
Cree's XLamp XM-L LEDs, commercially available in 2011, produce 100 lm/W at their full power of 10 W, and up to 160 lm/W at around 2 W input power. In 2012, Cree announced a white LED giving 254 lm/W, [10] and 303 lm/W in March 2014. [11] Practical general lighting needs high-power LEDs, of one watt or more.
This is the ratio between the total luminous flux emitted by a device and the total amount of input power (electrical, etc.) it consumes. The luminous efficacy of the source is a measure of the efficiency of the device with the output adjusted to account for the spectral response curve (the luminosity function).
High-power LEDs (HP-LEDs) or high-output LEDs (HO-LEDs) 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. [50] [51] LED power densities up to 300 W/cm 2 have been achieved. Since overheating is destructive, the HP-LEDs must be mounted on a ...
Mathematically, for the spectral power distribution of a radiant exitance or irradiance one may write: =where M(λ) is the spectral irradiance (or exitance) of the light (SI units: W/m 2 = kg·m −1 ·s −3); Φ is the radiant flux of the source (SI unit: watt, W); A is the area over which the radiant flux is integrated (SI unit: square meter, m 2); and λ is the wavelength (SI unit: meter, m).
In photometry, luminous flux or luminous power [citation needed] is the measure of the perceived power of light. It differs from radiant flux , the measure of the total power of electromagnetic radiation (including infrared , ultraviolet , and visible light), in that luminous flux is adjusted to reflect the varying sensitivity of the human eye ...
An active constant current source is commonly used for high power LEDs, stabilizing light output over a wide range of input voltages which might increase the useful life of batteries. Active constant current is typically regulated using a depletion-mode MOSFET (metal–oxide–semiconductor field-effect transistor), which is the simplest ...
Efficiency of power plants, world total, 2008. Energy conversion efficiency (η) is the ratio between the useful output of an energy conversion machine and the input, in energy terms. The input, as well as the useful output may be chemical, electric power, mechanical work, light (radiation), or heat. The resulting value, η (eta), ranges ...