| 摘要 |
PURPOSE:To detect precisely an amount of light without influencing a picture image by preparing in opposition to each other derectors that derect an amount of light on a light emitting part for control of an illumination lamp. CONSTITUTION:An illumination lamp 1 constitutes a light emitting part 8 for control together with a light emitting part for illumination and a remaining filament 3a. A reflecting plate 9 is prepared around the illumination lamp. At the front part opposing the emitting part 8 a temperature huse 11 is provided as a detector. The temperature huse is connected with a power source 12 in series with the lamp 1, detects temperature at the time of emission of the lamp 11 to permit one to know the amount of light, and when emitting abonomally, a current is interrupted. In stead of the temperature huse a photosensitive element is prepared, with this element the power source 12 may be controlled to permit an amount of light to be controlled. |
