| 摘要 |
PROBLEM TO BE SOLVED: To provide a lighting device that can more greatly prevent variation of luminescent color when the intensity of emitted light is controlled by pulse width modulation as compared with a case where no lighting control is performed.SOLUTION: A lighting device has a power supply unit 2 for supplying first driving energy to a first light emission element 11 and supplying second driving energy to a second light emission element 21, and a controller 3 capable of individually controlling the first driving energy supplied from the power supply unit 2 to a first light emission unit 10 and the second driving energy supplied from the power supply unit 2 to a second light emission unit 20. Light emission intensities of the first light emission unit 10 and the second light emission unit 20 obtained when the first light emission unit 10 and the second light emission unit 20 are made to emit light for the same driving time are measured while varying the driving time to obtain a measurement result. When the light emission intensity of the first light emission unit 10 is normalized by the light emission intensity of the second light emission unit 20, the light emission intensity of the first light emission unit 10 trends to increase as the driving time is shorter. The controller 3 controls so that the integrated value of the first driving energy is relatively lower than the integrated value of the second driving energy.SELECTED DRAWING: Figure 2 |
