| 摘要 |
PROBLEM TO BE SOLVED: To extend the life of a first light source and to enhance the relative color rendering property of a second light source without increasing the amount of work needed for lamp replacement. SOLUTION: This lighting system has a white LED 2 having a relatively good color rendering property and a relatively short life and a yellow LED 3 having a relatively poor color rendering property and a relatively long life, and a life extension means (sensor device 5) is provided for extending the life of the white LED 2. Thus, the life of the white LED 2 of relatively good color rendering property and short life can be extended by the life extension means, so the life of the white LED 2 can be prolonged. This eliminates a difference in life between the white LED 2 and the yellow LED 3, so the number of times of lamp replacement can be reduced to half as much as is necessary if the white LED 2 and the yellow LED 3 are simply mixed, and the labor and cost required for lamp replacement can also be reduced. The lighting system can improve the color rendering property, as compared with other lighting system such that illumination is provided solely by the yellow LED 3 of relatively poor color rendering property and long life. |
