How to improve the light efficiency of low-power LED lights? It was always a big challenge for LED lighting industry. Recently, researchers from MIT have created a new conversion device that can let LEDs generate more optical energy even higher than electrical energy they consumed. In other word, this new conversion device can increase the current light efficiency of LEDs to more than 100%. This invention made low-power LED lights emitting highly brightness light become feasible.
The working principle of LEDs is converting electrical energy into optical energy (emit light). Currently, a large number of experts and scientists are applying themselves to finding effective methods to create highly bright but more efficient LED lamps. One of the biggest obstacles to that is increasing the power consumption will lead to the reduction of light efficiency. According to the explanation of researchers from MIT, instead of increase the power consumption, they decline the input voltage dramatically. By calculation, when input voltage is cut into half, the power consuming will be dropped by 4 times. Simultaneously, the light efficiency will stably increase by 2 times. It is cleared that the dropping of power consumption will giving rise to the light efficiency.
During the tests, researchers dropped the consuming power to only 30pW, but measured the optical energy as high as 69pW, which gave out a light efficiency of 230%. When external voltage is applied on LEDs, holes and electrons within LEDs will be combined to generate photons. However, this combination occurred with a certain possibility. Unlike other researchers, scientists from MIT did not concentrated on this point to attempt to increase the light efficiency by raising this possibility. Instead, they made use of the tiny amount of heat caused by atomic lattice vibrations within equipments to generate more electrical energy.
This heat-utilized light-emitting method can cool down the working temperature of LEDs during the operation, which can also be considerate as a part of the cooling section. Under ambient conditions, this kind of cooling may have ignorable effects and very little practicality. It may probably be used in designing of heat-free lamps. When used as a heat pump, the device can contribute to solid-state cooling applications, like generators.