A vehicle headlamp has a reflector provided with a reflective area lying on a surface defined by rotating an ellipse about an axis which passes through the inner focus of the ellipse and which is inclined an acute angle (1.degree.-2.degree.) to the focal axis of the ellipse. A shielded filament for producing an inclined cut-off line to the beam is used and is orientated in the opposite sense to that in which it is orientated in a conventional headlamp for producing an inclined cut-off. To produce a Z-beam pattern, lensing at the front of the reflector splits the area of the basic beam pattern immediately below a horizontal portion of the cut-off line into parts which define upper and lower, mutually laterally displaced horizontal cut-off portions in the required Z-beam pattern. The lensing also utilizes a part-circular cut-off portion of the basic beam produced by the reflector and bulb to define an inclined portion of the Z-beam and depress and/or shifts other portions of the basic beam to reinforce other portions of the Z-beam. For U.S. lighting regulations, lensing at the front of the reflector has a first region which raises a portion of the beam defining the substantially horizontal portion of the opposite side, inclined cut-off; a second region which laterally shifts larger, substantially horizontal images spaced below the inclined portion of the opposite side-inclined cut-off so as to augment the images raised by the first region; a third region which deviates downwardly and laterally shifts those larger inclined images which are disposed above said larger substantially horizontal images to further augment the images raised by the first region; and a fourth region which spreads smaller images disposed outwardly of said horizontal and inclined larger images and also compresses in height the portion of the basic beam pattern made up of these smaller images.
A low beam headlamp for motor vehicles includes an objective made of pressed glass whose one side is formed as aspheric partial surfaces of identical or different aspherity. The partial surfaces are staggered in the direction parallel to the optical axis of the objective and the resulting step has rounded edges. The aspheric partial surfaces adjust light distribution to achieve a desired quality of the light-dark boundary zone projected on the driveway, and provide corrected color fringes of the passing light beam.
The optic axis of a vehicle headlight comprises a reflector, an incandescent helix and a convergent lens. The reflection surface of the reflector is parabolic in the horizontal midplane section and is elliptical in vertical median section. A narrow band of light spreading out laterally is thus produced without supplementary optical components, particularly the diffusion disk or dispersion lens. A sharp light-to-dark boundary is obtained by a diaphragm having an effective straight edge 18 located below the outer ellipse focus, which is coincident with that one of the principal foci of the converging lens which is the nearer to the reflector.
A structure is provided for headlamps for vehicles, having a light source, a reflector, and a front lens in which the lens is slanted with respect to a vertical direction of a vehicle body, a rear surface of the lens is formed with a prism zone for forming a light diffusion zone on a light distribution pattern of a given screen and another prism zone for forming a hot zone on the distribution pattern, and the reflector is formed with a first reflecting surface which corresponds optically to the light diffusion zone forming prism zone and diffuses light beams emitted from the light source in a horizontal cross section with respect to an optical axis of the light source and reflects the light beams of the light source substantially in parallel to the optical axis in a vertical cross section and with a remaining reflecting surface substantially in the form of a paraboloid of revolution. Consequently, both ends of the light distribution pattern in the horizontal direction neither droop nor rise.
A vehicular headlamp in which the radial beam of radiated light is continuously adjustable between a first position and a second position. Semi-cylindrical lamp shields surround a lamp. The lamp shields are attached to gears which operate to rotate the lamp shields radially about the lamp. An actuator is attached to the gears, such the actuator can turn the gears in order to rotate the lamp shields. The actuator is controlled by a circuit which prevents over-rotation. The actuator may move in very small increments, such that the lamp shields may be continuously adjustable between the first position and the second position. The lamp shields are thus continuously adjustable to vary the projected radial beam of the headlamp.
A headlight has a parabolic shaped reflector (8) with an incandescent lamp whose filament (13) is defocussed, or approximately at a focus point for distribution, by the reflector. A light-transmissive shield (4) has upper and lower zones (1 and 2) with prism-like optical devices (5 and 6) thereon which are respectively positioned above and below a horizontal middle plane of the reflector. Both zones are bordered by a vertical middle plane of the headlight. The upper zone extends to an oncoming traffic side while the lower zone extends to the other side and its upper edge is approximately bordered by the horizontal middle portion of the reflector. In this connection, the prism-like optical devices are arranged so that light beams passing therethrough are diverted to a partial area (100, 200) of a light figure of the headlight which, on a driving side, is at a higher level than on the oncoming traffic side.
