| 摘要 |
PROBLEM TO BE SOLVED: To provide a lighting system in which the amount of light of illumination light can be controlled in high precision by compensating the output-passage of time characteristics of an LED and the output-passage of time characteristics of a photosensor and cost reduction is realized by compensating the above passage of time characteristics without using a timer. SOLUTION: A memory part 6 stores a first table which shows corresponding relations of the passage of time variations of the detection output of the photosensor 5 and the accumulated lighting time of the LED 2 and a second table which shows a correction value of the detection output corresponding to this time. Since a time estimating part 71 estimates the accumulated lighting time by referring to the first table, the output-passage of time characteristics of the LED 2 and the photosensor 52r or the like can be compensated without using a timer, and cost reduction can be realized. Furthermore, since a correction part 72 corrects the detection output using the correction value corresponding to the estimated accumulated lighting time shown by the second table, and feedback controls the LED 2, the passage of time characteristics can be compensated. Therefore, the amount of light of the illumination light can be controlled in high precision. COPYRIGHT: (C)2009,JPO&INPIT |
