Quantum Dot Hybrid OLED That Emits Warm White Light Without Sacrificing Efficiency

Organic Light Emitting Diode Produces More Attractive Light at Low Cost

Blue and green emitters in this organic light emitting diode (OLED) produce the attractive, warm, white light - similar to an incandescent bulb's - desired by consumers, without sacrificing energy efficiency. Quantum dots dispersed in a microlens array give the hybrid OLED enhanced optical properties. OLEDs may soon replace traditional incandescent lighting technologies since they last longer and are more efficient, less expensive to manufacture and better for the environment. Though traditional LEDs are more efficient, they cannot produce the attractive white light associated with inefficient incandescent bulbs, leaving consumers reluctant to switch. OLEDs have both the efficiency of LEDs, and the ability to produce the warm, white light preferred by consumers. Researchers at the University of Florida have improved on existing OLEDs by adding quantum dots that help convert the light from the blue and green emitters to the warm white light. Hundreds of millions of dollars have been invested in OLED lighting technologies around the world. The OLED lighting market is forecast to reach $1.5 billion by 2015 and $6.3 billion by 2017, with 75 percent of revenues in 2017 coming from commercial and industrial buildings.

Application

Highly efficient hybrid OLEDs with enhanced optical characteristics, which will enable the development of next-generation OLED lighting panels

Advantages

• Contains blue and green emitters, increasing luminous power efficiency
• Features quantum dots that down convert the blue and green light to produce a desired combination of wavelengths, resulting in the pleasant warm white light associated with incandescent light bulbs
• Includes microlens arrays on the light exiting surface to enhance light extraction, offering higher efficiency at lower operating costs
• Compatible with roll-to-roll manufacturing processes for OLED panels, removing a barrier to market entry

Technology

Researchers at the University of Florida have discovered that using hybrid blue-green organic LEDs, in conjunction with microlens arrays containing down conversion quantum dots dispersed in a transparent polymer, produces warm white light with a high degree of efficacy. Quantum Dots down-convert a portion of the emitted light to higher wave lengths, and the microlens arrays increase light extraction. The combination of these two advancements creates bright, warm white light. Improvements in brightness, color rendering, and color temperature result in superior performance characteristics over existing LED technologies that will allow for the development of high-performance, low-cost lighting panels.