| 摘要 |
<p>Self-heat-generating adjusting type heating sources (7) are provided near light sources (6) and light reflecting layers (8 and 9) are provided between the light sources (6) and the heating sources (7). Therefore, the heating sources (7) do not thermally run away, because no temperature detecting means nor control circuit is required for controlling the heating sources (7). In addition, the quantity of light intercepted by the heating sources (7) is reduced, because light emitted from the light sources (6) is reflected by the reflecting layers (8 and 9).</p> |
