To illustrate the characteristics of white LEDs, first look at the status of the light source used. Incandescent and tungsten halogen lamps have a luminous efficacy of 12 to 24 lumens per watt; fluorescent lamps and HID lamps have a luminous efficacy of 50 to 120 lumens per watt. For white LEDs: In 1998, the efficacy of white LEDs was only 5 lumens per watt. By 1999, it had reached 15 lumens per watt. This indicator is similar to general household incandescent lamps. In 2000, the efficacy of white LEDs was similar. It has reached 25 lumens per watt, which is similar to a tungsten halogen lamp. Some companies predict that by 2005, the luminous efficacy of LEDs can reach 50 lumens / watt, by 2015, the luminous efficacy of LEDs is expected to reach 150 ~ 200 lumens / watt. At that time, the working current of the white LED can reach the ampere level. It can be seen that the development of lighting sources for white LED writers will become a possible reality.
Incandescent lamps and tungsten halogen lamps for general lighting are cheap, but the light efficiency is low (the thermal effect of the lamp is white and power consumption), the life is short, and the maintenance workload is large, but if the white LED is used for illumination, not only the light effect is high, but also the life is long. Long (continuous working time of 10,000 hours or more), almost no maintenance.
LED light source has the advantages of using low-voltage power supply, low energy consumption, strong applicability, high stability, short response time, no pollution to the environment, multi-color illumination, etc. Although the price is more expensive than existing lighting equipment, it is still considered to be Inevitably replace existing lighting devices.