| 摘要 |
<p>In the headlamp, light reflected from an incandescent or arc source (10) at the nearer focus (FR) of the uniformly elliptical central reflector (21) converges at the outer focus (FS), located at the focal plane (PF) of the lens (40). The lamp front is closed by a plain glass (50). While the outer reflecting zones (22a,22b) also reflect convergently in vertical planes, horizontally reflected rays cross the optical axis (Ox) progressively further forward (h(yc)) as the reflection point lies further out (yc). The beam appears at the focal plane as a bright central spot with lateral extensions of approximately uniform height. To produce cut-off, a vertical mask (30), with a top edge not extending higher than the optical axis (Ox), is fixed at the focal plane (PF).</p> |
