| 摘要 |
PROBLEM TO BE SOLVED: To provide an illumination device that has an improved illumination device having at least two lamps positioned with in focus of a hollow mirror used as a reflector, and that has such a high operation certainty that the changeover at the time of a lamp failure can be done without any actual delay in time and without changing drastically the illumination range. SOLUTION: At least two hollow mirrors 2, 3 are arranged along a common optical axis 4 which has common light-emission direction, and at least one of there hollow mirrors is structured as a ring-shaped reflector 3. The hollow mirror has plural focuses 6, 8 arranged on the optical axis with an interval from each other, and with in each of these focuses 6, 8 each of lamps 5, 7 as an illumination means is arranged. |
