Application Of Light-emitting Diode
1. LED Display
Since the mid 1980s, there has been a monochrome and multi-color display, initially a text screen or moving painted. The early 90, the development of computer technology and integrated circuit technology, LED display video technology to achieve, television images directly on the screen, especially in the mid-90, Blue and green ultra-high brightness led development and rapid production, so that the application of outdoor screen greatly expanded, the area of 100-300m ranged. At present, the LED display in stadiums, squares, venues and even streets, shopping malls have been widely used, the United States Times Square on the Nasdaq full color is most famous, The screen area is 120 feet x90 feet, equivalent to 1005m, made from 19 million super bright blue, green and red LEDs. In addition, in the Securities market screen, bank exchange rate screen, interest rate screen and other applications also accounted for a large proportion, recently in the expressway, The information screen of elevated road also has a great development. The application of light-emitting diode in this field has been scaled up to form a new industry and can expect more stable growth.
2. Traffic lights
Beacon Lamp using LED as light source for many years, the current work is to improve and improve. Road traffic lights have made great progress in recent years, technology development faster, rapid application development, China currently has 40,000 sets of orders per year, California in the United States in the last year with the LED traffic lights replaced 50,000 sets of traditional light source lights, according to the use of effect, long life, save power and maintenance-free effect is obvious. At present, the LED peak wavelength is red 630nm, yellow 590nm, Green 505nm. The problem that should be noted is that the driving current should not be too large, otherwise the high temperature conditions in the summer sun will affect the life of the LED.
Recently, it has been successfully used as the LED airport special light signal for the airfield as beacon, projection light and omni-direction lamp. Multi-party reflection effect is very good. It has independent intellectual property rights, approved two patents, good reliability, save electricity, maintenance-free, can be extended to a variety of airports, replacing the old lights have been used for decades, Not only the brightness is high, and because the LED light color purity is good, particularly distinct, easy to signal recognition [1].
Railway lights because of the variety series, the requirements of light intensity and perspective is also different, is being intensified in the development, is expected to gradually develop successfully and put into application, from the quantitative point of view, is also a considerable market.
3. Automobile lamp
Ultra-bright LED can be made into a car brake lights, taillights and directional lights, can also be used for instrument lighting and car lighting, it in vibration resistance, power saving and long life than incandescent lamp has a clear advantage. Used as a brake light, it has a response time of 60ns, much shorter than the 140ms of the incandescent lamp, and travels on a typical freeway, will increase the safe distance of 4-6m.
4. LCD backlight
LED as a liquid crystal display backlight, it can not only as green, red, blue, white, can also be used as color backlight, many products have entered the production and application stage. Recently, the LCD screen on the mobile phone to make back light source, improve the product grade, the effect is very good. 8 Blue, 24 green, The backlight of 15in (1in≈2.5cm) LCD screen made of 32 red luxeonled can reach 120W, $number lm, Brightness 18000nits ($literal). 22 LCD backlight is also made, only the 6mm thick, not only the color mixing effect is good, The color index also reaches more than 80. At present, the large-scale backlight is in the development stage, but the potential is great.
5. Lighting
As the brightness of the light-emitting diode increases and the price drops, coupled with long life, energy-saving, drive and control is simpler than neon, not only can flicker, but also can change color, so with ultra-high brightness led made of monochrome, multi-color and even discoloration of the light-emitting column with other shapes of colored light units, decorative tall buildings, bridges, Streets and squares and other landscape works very well, showing a faction of colorful, starlight flashing and streamer splendor of the scene. There are many units to produce LED light beam up to more than million meters, lantern tens of thousands of, is being gradually promoted, it is estimated that will gradually expand the formation of a separate industry.