In a lighting apparatus which illuminates light ray from an illumination light source through a light distribution lens onto an illuminated surface, an inner surface of the light distribution lens is formed as continuous surface to receive incident ray in the perpendicular direction, and an outer surface of the lens for refracting outgoing ray is formed based on the equations which are made in consideration of the illuminance on the illuminated surface, thereby uniform illuminance is obtained on the illuminated surface.
A display has a member irradiated by a surface light source device comprising a light diffusion member and emission device. The emission device is provided with a light flux control member having a recess and light control emission face which is configurated so as to satisfy Conditions 1 and 2 in a range at least covering a half-intensity-angular-range. Light emitting element(s) may be sealed. Condition 1 is that relation .theta.5/.theta.1>1 is satisfied except for light emitted from a light emitting element toward within an angular-neighbourhood of a standard optical axis of the emission device, and Condition 2 is that value of .theta.5/.theta.1 decreases gradually according to increasing of .theta.1, where .theta.1 is an emission angle of any light at being emitted from the light emitting element, and .theta.5 is an emission angle of that light of .theta.1 at then being emitted from the light control emission face of the light flux control member.
A light projection apparatus for projecting an illuminated line onto a surface which comprises a light source for emitting a light beam and a light beam deflection lens which is adapted to receive the emitted light beam and project a work light beam which will be visible as a straight line on the surface, the light deflection lens is configured so that the visible line on the surface is of generally equal illumination along its entire length. The light beam deflection lens preferably comprises an optical lens which is adapted to refract and reflect the emitted light beam.
A condenser lens for a projection system optimizes the amount of overall brightness directed toward an aperture and the uniformity of illumination at the aperture. The lens, when placed in the projection system, has a marginal ray which starts at the center of the light source, passes through the edge of the condenser lens, and intersects the region to be illuminated at or near its edge. The lens further has a relative zonal ray height which is selected based on the distance from the light source to the aperture. The condensing lens system is particularly useful in the construction of overhead projectors.
A reduced package depth low profile headlamp includes a light source emitting light in an elongated shape with a length longer than a width. The length forms a predetermined angle with respect to the horizontal axis to generate light within predetermined a cutoff. A converging lens receiving light from the light source has an optical axis. The lens has a spherical inner surface with a center and an elliptical outer surface having a first and second focal point. The light source is positioned substantially on the optical axis so that the light source is substantially at the center of the spherical inner surface and the first focal point of the elliptical outer surface is substantially coincident with the center of the spherical inner surface.
A display case having lenses mounted in the case that distribute or direct light emitted by fluorescent tubes located near the ends of display shelves toward the shelves in order to provide a more uniform light distribution along the length of the shelves. The lenses facilitate the illumination of items placed on the shelves near the front and middle of the shelves. Light-directing portions of the lenses distribute or direct light emitted from the fluorescent tubes located inside the lenses toward the display case shelves.
