| 摘要 |
The invention relates to a vehicle headlamp with a suitable polymeric casing (4) surrounding from all sides a free-surface reflector (5) integrated into the casing (4), preferentially of oval shape with a typical thermal load density P more than 0,6 W/cm2 and a reflecting layer made of thin-layer aluminium, fitted with a mineral or polymeric transparent cover glass (3) on the front side and a bulb (1) as a light source with a glowing filament (2), installed at the reflector's (5) central position. It is foreseen according to the invention, that the ratio between the distance of the reflector (5) from the glowing filament (2) of the bulb (1) and the thermal load density amounts to more than 17 mm cm2/W. Further, the reflector (5) is typically thinner on the face between the means (71) and (72) for connection of the reflector (5) with the control assembly and above the bulb (1) than on the remaining reflector's faces. Besides, the reflector's (5) shell is made of an amorphous thermoplast with a glass transition temperature Tg greater than 210 degrees Celsius. |
