Lexington-based QD Vision,Inc.,a spinoff of MIT,has developed Quantum LightTM Optic and the lamp is termed a quantum LED(QLED),to produce both lamps and downlighting fixtures that emulate the warm colors of an incandescent bulb but provide much greater light power and lamp life-time.The mechanism behind this extraordinary development is the redistribution of color by means of"quantum dots".The ability to tune the color of a quantum dot offers a way to redistribute the harsh LED light by placing a specially designed layer of quantum dots in front of the LED lamp thereby effectively transforming a portion of the overly abundant LED blue light into a warmer red light.The overall effect of the quantum dots is to produce illumination that is much closer to natural light.
This ability to redistribute color using a quantum dot is extraordinary.The fact that the conversion efficiency from turning blue light into red,or orange,or yellow is almost one-hundred percent was the final breakthrough.The light power of the LED is retained,only its color is changed.QD Vision uses this mechanism to manufacture a quantum dot thin-film-plate optic that is placed over the LED(refer to photo).The QDVision Optic uses photoluminescence to achieve QLED performance.Photoluminescence occurs when incident light excites the quantum dot to emit.However,quantum dots can also be excited electrically(electroluminescence)and this characteristic opens up another realm of marketing possibilities.In fact,the company was recently awarded a 1.38 million dollar contract by the U.S.Department of Defense to develop specialized devices based on electroluminescent quantum dots.QD Vision's achievement in quantum dot nanotechnology has led to the creation of a more natural light that requires less power.In addition,the color of the light is precisely tunable.This breakthrough has opened the door to new possibilities in energy conservation.
