摘要 |
PROBLEM TO BE SOLVED: To limit the occurrence of fogging in a portion for adversely affecting the light distribution of a front lens by gradually increasing the thickness of the design face portion of the front lens from a part in which the level of temperature increase caused by heat generated by a bulb in a lamp room to a portion in which the level of its temperature increase is small. SOLUTION: A front lens 9 is one transmitted by an irradiating light and this lens is composed of a design face portion 9b positioned in an external surface being attached to a vehicle so as to be visible and a sealing leg portion 9a provided in the peripheral edge of this design face portion 9b for the purpose of being fitted in a fitting groove 8a formed in the peripheral edge of the opening part of a lamp body 8 and normally invisible because of its position behind a car body. When the design portion 9b of the front lens 9 is suddenly cooled during raining or washing, although a temperature is lowered in the inner surface side of the lens 9, since the thickness T2 of the surface part 9b of the lens 9 in a portion (region B) in which the level of a temperature increase caused by head generated by the bulb 19 of a sub lamp 5 (6) is small is thicker compared with the thickness T1 of a region A portion, dew condensation is easily generated starting from the part of the leg part 9a. |