| 摘要 |
<p>548,133. Vehicle lamps. BRITISH THOMSONHOUSTON CO., Ltd. (General Electric Co.). Nov. 7, 1941, No. 14381. [Casses 39 (ii), 75 (ii) and 75 (iv] In a vehicle headlamp comprising a light source mounted in definite optical relation to a reflector fitted at its mouth with a lens formed on one surface with vertically spaced horizontally extending prisms the emission of upwardly directed rays is prevented by a shield adjacent the light source and by an opaque covering on the base of the prisms. Fig. 2 shows a headlamp of the type described in Specifications 515,091 and 526,924 comprising a pressed glass paraboloidal reflector 11 and a lens 12 fused together at their. peripheries and enclosing a linear coil filament 13 supported at the focus of the reflector by leading-in wires 16 hermetically sealed in metal cups 19 fused to the glass. A shield 27 consisting. of a semi-circular plate or a quadrant of a sphere is mounted near the light source on an arm welded to one of the leading-in wires 16. The lens 12 is provided on its inner surface with vertically extending flutes 23 to spread the light rays horizontally and with horizontally extending prisms 24 to refract the rays vertically, the bases 25 of the prisms being coated with graphite, oxidized copper, silica, or aluminium or other opaque non-reflecting materials 26. The reflector surface adjacent the leading-in wires is preferably left free of reflecting material and the shield 27 is preferably coated with a dull black non-reflecting ceramic material. In another construction the headlamp is fitted a small sealed bulb containing a filament, the front portion of the upper half of the bulb being coated with opaque material.</p> |
