In the 1970 's, the first gap, gaasp, red, yellow, green, low luminous efficiency led has been applied to indicators, numbers and text display.
From this led began to enter a variety of application areas, including aerospace, aircraft, automobiles, industrial applications, communications, consumer products, etc., throughout the national economy departments and households. By 1996 the world's sales of LEDs had reached billions of dollars. Although for many years led has been limited by color and luminous efficiency, but because Gap and gaasp led has long life, high reliability, low working current, and TTL, CMOS digital circuits compatible with many advantages and thus has been the user's green squint. In the last 10 years, high brightness and full color has been the frontier subject of the research of LED materials and devices technology. Ultra-high Brightness (UHB) refers to the luminous intensity of up to or exceeding 100MCD led, also known as Candela (CD)-grade LED.
The development of high brightness A1GAINP and InGaN LED is very rapid, and it has reached the performance level that conventional materials gaa1as, gaasp and Gap can not achieve. 1991 Japan Toshiba and the United States HP Company developed into ingaa1p 620nm Orange ultra-high brightness led,1992 years ingaa1p590nm yellow ultra-high brightness led utility. In the same year, Toshiba developed ingaa1p 573NM Yellow-green ultra-high brightness led, the method to light up to 2CD. 1994 Japan Asia Company developed into a InGaN 450nm blue (green) color Ultra high brightness led. At this point, the color display of the three primary colors required red, green, blue and orange, yellow, a variety of color LED has reached the candela level of luminous intensity, the realization of ultra-high brightness, full-color, so that the outdoor full-color display of light-emitting tube to become a reality. China Development led started in the 70 's, the industry appeared in the 80 's. The country has about 100 enterprises, 95% of the manufacturers are engaged in the production of back-road packaging, the required tube core almost all imported from abroad. Through several "five-year Plan" of technical renovation, technical research, the introduction of foreign advanced equipment and some key technologies, so that China led production technology has stepped forward.