The highest luminous efficiency of the world's brightest white LED

CITIZEN electronics has developed a series of successful 245lm CL-L100 light beams per LED module in the world's brightest white light-emitting diode (LED)". Output 245lm power consumption of 3.5W, luminous efficiency of 70lm/W. "Fluorescent lamp with the same luminous efficiency".

If ten of this white LED connected with 12V drive voltage, power consumption of 35W can output beam 2450lm. This value is equivalent to 60% of the power consumption of the car halogen lamp brightness of the beam of 1.6 times. CITIZEN electronics is scheduled to start production in 2006, will be used for lighting equipment, LCD panel backlight, car headlights, etc.. CITIZEN plans to increase luminous efficiency to 90lm/W by the end of 2006. If we can further improve the luminous efficiency, the production stage of the white LED luminous efficiency, will reach a high performance fluorescent lamp and HID lamp level.

The installation area of LED module are elongated 4mm * 40MM, the thickness of only 0.75mm. Therefore, the module can be arranged in a longitudinal direction to obtain a linear light source, such as a fluorescent lamp and a cold cathode fluorescent tube (CCFL). If the horizontal arrangement module, can get planar light source. If the module is arranged in a circular shape, the same shape as the current automobile lamp can be obtained.

The development of white LED by the blue LED chip and yellow phosphor material, in order to obtain high brightness, CITIZEN electronics installed 24 blue chip in the LED module. In addition, the bottom plate of the mounting chip is irradiated by the phosphor material with high luminous efficiency, and the emitted light is effectively emitted to the outside of the module. In order to reduce the temperature rise and reduce the luminous efficiency under the high drive power of the 3.5W, CITIZEN has used the copper material with good thermal conductivity. Including the chip, including the module thermal resistance of 6K/W, only for the company's supply of 60lm products 1/5. The blue LED chip purchased from Nichia chemical industries.

In order to be able to connect a plurality of simple white LED, white LED with screw connection. White LED is made of parts made of anisotropic conductive material. When connecting 10 white LED, the resistance of the screw part (a total of 20) is about 0.5.

CITIZEN electronics plans in "Nikkei Electronics" held on June 24th technical seminar "white LED 2005" on the development of white LED is introduced in detail. Source: Lighting Engineer Community