EDI-T® :
Technological Surprises to Sharpen Cutting
Edges of
The first commercial light-emitting diode (LED) was
introduced in 1962. Since then, the performance of LEDs has been improved
continuously with a breath-taking acceleration of progress in the last
decade, which has resulted in the commercialization of the
super-brightness or academically, high-brightness (HB) LEDs in early
1990s. HB LEDs enjoy various advantages in terms of efficiency, available
emission spectrum, higher power, higher speed, and application methods.
These advances, coupled with the inherent properties of solid-state
devices, ruggedness, low-voltage operation, low-power consumption, high
reliability, longevity, and low cost, have captured HB LEDs into a wide
range of practical applications, from telecommunications, to solid-state
lighting (SSL), to displays. In each case, HB LEDs are increasingly replacing
the conventional technologies.
Nowadays HB LEDs cover the entire visible color spectrum from blue (450~477nm) to red (629~650nm) and achieve impressive levels of emission power and conversion efficiencies. Lamps based on red, green and blue HB LEDs can produce nearly any color, including white light. The white light luminous efficacy of HB LEDs is now more than 30 lm/W (red-orange HB LEDs having achieved 100 lm/W) and exceeds that of traditional fluorescent lamps. They are expected to reach more than 50 lm/W by year 2005, approaching the efficacy of most compact-fluorescent lamps, and to reach 180-200 lm/W by year 2020.
The development of HB LEDs has been enabled by two material systems, AlGaInP (for red, orange, amber & yellow) and AlGaInN (or InGaN) (for blue, green & white). Also, organic LEDs as an emerging solution for display applications have made some very significant progress in the recent years. New approaches like encapsulating semiconductor quantum-dots (nanoparticles approximately one billionth of a meter in size), instead of quantum-well technologies, has also been requesting a revolution in HB LEDs study through nanoscience. Altogether, the revolutionary development of HB LEDs technologies will not only lead to an increased replacement of traditional lamps but also create a whole range of new applications in our daily life. These semiconductor growth technologies have enabled applications where several single to several millions of individual LEDs can be packaged together to be used in high-efficient portable lights, LCD display backlight, full color signs, automotive interior and exterior signaling applications, including traffic signals. However, the most exciting will be ultra-efficient solid-state lighting (SSL) to replace general illumination (made of incandescent and fluorescent lighting), which transforms the illumination industry and saves billions of energy costs!
More information on HB LEDs can be found at FAQs of EDI-T® Battery-Free & Consumption-Free LED Flashlights.