A headlight for a vehicle operating in accordance with a projection principle has a reflector, a light source, a lens through which a light emitted by the light source and reflected by the reflector passes, at least partially light-permeable element which at least partially surrounds the lens at least over a part of its periphery and is provided locally with optical profiles so that the light emitted by the light source and not engaged by the reflector passes through the element and is collected by the element, the light reflected by the reflector and passing through the lens forming an upper bright-dark limit, and at least one additional light source which produces a limiting light and is arranged so that the light emitted by the at least additional light source at least partially passes through the element.

Light-transparent lens structures typically formed of conventional synthetic acrylic resins and intended for use as lenses in a lensed fluorescent troffer or similar lighting fixture, the lens structures of the invention are characterized by repeating patterns of conical or pyramidal depressions formed in the lens with upper portions or apices thereof being inverted. The lens structures of the invention preserve the angular relationships of lens material to air interfaces of conventional conical lens patterns, for example, and further preserve angular beam shaping capabilities while substantially reducing the amount of material needed to form the lens structures per se.

A lenticular lens containing a multiplicity of multi-sided lenticules useful with reflector lamps provides improved light distribution by having the lenticules oriented to avoid parallelism with a projected light image and distributed in a plurality of zones or bands concentric about said optical center. The size and light-spreading ability of the lenticules in each zone is selected to provide the desired light distribution. Parallelism is avoided by having the lenticules arrayed in a plurality of wedge-shaped sections circumferentially arranged in a circle around the optical center of the lens and extending through the zones with the lenticules in each section arrayed in a uniform, close-packed hexagonal array of parallel rows with the longitudinal axis of one of the rows being radially aligned with respect to the optical center of the lens, so that none of the sides of the lenticules are parallel to the light source image projected off the reflector.

An infrared heat lamp has a reflector body closed by a lens and having a source of infrared radiation positioned within the body. The lens has a plurality of lenticules formed thereon to provide substantially uniform radiant intensity within a 50.degree. cone on a planar surface spaced from the lens, the radiant intensity varying as the inverse of (cos .beta.).sup.2. In a preferred embodiment all of the lenticules have a parabolic shape.

Primary light from primary light source (LED) is supplied toward a light an input face of an light control member. The light input face is provided with a plurality of projections for light input promotion. Each projection is composed of a generally spherical top portion and tapered column-like portion. Height of each projection may greater than a distance as far as an adjacent projection. An light output face of the light control member may be provided with of a plurality of projections having a function of causing an inner incident light to be deflected as to approach a frontal direction on being emitted, or may be formed of a roughened surface. A light flux control member may be interposed between the primary light source and the light control member.