Abstract: A backlighting device for display panels operating on the edge lighting method that comprises a light conducting plate made of a light-transmissive material, a layer of light-diffusing material that partly covers one major surface of the light conducting plate, and a light diffusing/reflecting plate that covers the thus covered area of the light conducting plate. The light conducting plate is provided on its exit face with a film that is coarser grained on the exit face than on the entrance face (the side closer to the light conducting plate) and which, when provided on the exit face of the light conducting plate, will increase the luminance of light issuing from the exit face of the light conducting plate. This backlighting device produces satisfactory luminance and can be used as a high-performance model that achieves a high efficiency of power to luminance conversion at least in the direction of the line normal to the exit face.

Abstract: The invention provides an intermediate screen for a signal light, the screen being of the type constituted by a plate for passing a flux of light, and including a set of light-deflecting grooves on at least one of its faces, the grooves being essentially concentric and each being defined by two faces of essentially rectilinear profile and of given angles of inclination relative to the normal to the plate. For at least one subset of adjacent grooves, the angles of inclination of the faces defining each groove vary from one groove to another and are such that the sum of said angles is constant.

Abstract: In an illuminating instrument, a reflector is composed of a combination of two ellipses whose respective optical axes are spaced from each other in a cross-sectional plane containing an optical axis of an illuminating optical system. A light source has its center located between the optical axes of the respective ellipses. A condenser is arranged at an opening of the reflector.

Abstract: A lighting device for use with vehicles comprises an outer lens attached to the front opening of a housing, an inner lens located inside the outer lens at the front opening of the housing, and a transparent sheet interposed between the outer and inner lenses and smoke-treated on its outer surface. The device further comprises light sources located inside the inner lens, engaging pins made integral to the outer or inner lens, and engaged holes formed in the transparent sheet and engaged with the engaging pins of the outer or inner lens.

Abstract: A task light panel for use with a light source for illuminating a work surface. The panel comprises an upper surface having a plurality of transverse grooves formed thereon and a lower surface having a plurality of longitudinal grooves formed thereon. The transverse and longitudinal grooves are substantially perpendicular to each other and are adapted to distribute light from the light source onto the work surface, reduce glare or veiling reflections from the work surface, and block direct viewing of the light source by an individual using the work surface.

Abstract: A task light panel for use with a light source for illuminating a work surface. The panel comprises an upper surface having a plurality of transverse grooves formed thereon and a lower surface having a plurality of longitudinal grooves formed thereon. The transverse and longitudinal grooves are substantially perpendicular to each other and are adapted to distribute light from the light source onto the work surface, reduce glare or veiling reflections from the work surface, and block direct viewing of the light source by an individual using the work surface.

Abstract: A vehicular number plate including luminous characters of the type comprising a number plate having a plurality of chracter portions punched therefrom to which a plate molded of a transparent or translucent synthetic resin is adhesively secured and illuminating bulbs for illuminating the character portions, wherein a light scattering plate having a number of quadrangular pyramid-shaped light scattering projections formed thereon is interposed between the number plate and the illuminating bulbs in an area corresponding to positions where the illuminating bulbs are disposed. Each of the quadrangular pyramid-shaped projections has an apex angle which is determined in the range of 90.degree. to 160.degree.. The illuminating bulbs may be replaced with a single fluorescent lamp. In this case, the light scatteering plate includes a receiving portion in which the fluorescent lamp is received and a light scattering portion extending from the receiving portion while having a gradually reduced thickness.

Abstract: An illuminating optical device of the type in which light from a light source is made incident on a condenser lens through a fly-eye lens a light transmitting object to be illuminated is disposed between the condenser lens and a projection optical system. The degree of surface finish of the emergence surface of the fly-eye lens is made lower than that of the incident surface.

Abstract: A refractive lens member for use with a luminaire is constructed to minimize high angle glare. The grid comprises a plurality of lenses which are interconnected by a rib structure to form a pattern of lenses in a network grid, with the lenses all lying substantially in the same plane. Each individual lens has a flat circular light incident surface and each lens has a substantially convex, spherical section light emergent surface. The rib structure is made of the same material as the lenses and may be integrally formed with the lenses to form the network grid. The rib structure is constructed to cooperate with the lenses to which prevent light at angles outside a pre-established range arrives on the light incident side surfaces from exiting from the light emergent surfaces of said lenses.

Abstract: According to the invention clear and yellow transparent zones are provided on the surface of a light diffusing element associated with a headlamp for a moving vehicle. The light emitted from the lamp has the characteristics of both white and yellow light. High intensity white light provides satisfactory illumination for highway driving, while the yellow light emitted penetrates fog, dust and/or smoke better than the ordinary white light. The benefits of both light are realized with a single lamp. The coloration of the light diffusing member can be accomplished by treating a conventional white light headlamp.

Abstract: An illuminated display forming part of a twist type switch is disclosed. An operator display is formed from a transparent material having a high index of refraction. A cylindrical portion is formed on the back of the operator display which is mounted on the switch and defines a space in which an indicator lamp is mounted. A peripheral flange portion is formed forward of and radially outward from the cylindrical portion. The rear surface of the flange portion is contoured with a plurality of prisms which are arranged in the shape of the information to be displayed. The prisms concentrate and collimate the light emitting from the indicator lamp and passing through the cylindrical portion and direct it out the front of the operator display. The transverse cross section of the resulting beam is in the general shape of the display and is readily visible to an observer in front of the display.

Abstract: Lighting fixture including an enclosure, means disposed in the enclosure for supplying a central source of light therein, a concave, generally parabolic reflector for directing a main beam of light out of the enclosure from the source generally along a given optical axis, the central source of light being located at the focal region of the concave reflector, the concave reflector having a light penetrable region thereof disposed at least at one side of the optical axis in a horizontal plane in common with the central light source, the light-penetrable region forming an escape window out of the enclosure for part of the light from the source.

Abstract: An lighting apparatus including a housing having an opening, a light source received in the housing and a light transmitting-cover fixed at the opening of the housing and through which light rays are projected from the light source. The light transmitting-cover includes a plate made of light transmitting-material and having a first surface and a second surface. Segment lens elements of the same size are arranged on the first and second surface of the plate and formed integrally with the plate. The segment lens elements on the first surface are positioned in face-to-face relation with the segment lens elements arranged on the second surface, thus forming a segment lens. The segment lens elements have a common optical axis and convex surfaces, respectively. The focal lengths defined by these convex surfaces are equal.

Abstract: A vehicle lamp assembly has a light source, a light transmitting member, baffle elements of light absorbing material extending perpendicular to the surface of the light transmitting member towards the light source and lens means located between the baffle elements and the light source so as to concentrate light from the light source between adjacent baffle elements. The ends of the baffle elements abutting the light transmitting member are of a color chosen in accordance with the required appearance of the lamp assembly when the light source is not illuminated and the rest of the baffle elements are black.

Abstract: A spot lamp having a lens in the form of a curved member having an inner surface with a series of radially disposed flutes formed therein defining a fluted portion which surrounds a centrally disposed stippled portion. The flutes each extend linearly from a position adjacent the stippled portion outwardly to a position adjacent the outer edge of the curved member. The surfaces of the flutes are also stippled.

Abstract: The invention provides a lantern for an area light, particularly one having a cut-off light distribution. A central area of a transparent or transluscent bowl of the lantern has in alternation externally facing reflecting prisms and flats. There are sufficient flats to transmit at least one third of the vertical light and sufficient proportion of prisms to provide a completely flashed prism bank at the direction of peak intensity which is preferably 60.degree.-65.degree. from the vertical. The prism bank controls the vertical light, so that the intensity in a vertical 60.degree. cone does not exceed 80% of peak intensity, more efficiently than internal prisms. The flats have the additional advantage of facilitating ease of cleaning.

Abstract: A luminaire adapted to be mounted at the top of a post and to direct light below a horizontal plane is disclosed. A housing element preferably of a polycarbonate material comprises a housing for an electrical system and a refractor means having an interior and exterior prismatic structure.

Abstract: The invention relates to a beacon lamp which includes a point source of light located at F and surrounded by a transparent cap (20) which is in the shape of a solid of revolution about an axis zz' which passes through F and which forms at least one annular lens (L1, L2) whose focus is F. The profiles of the optical surfaces of the lens(es) are such that they produce a cap which can easily be moulded and which is anastigmatic for the point F and infinity, i.e. which concentrates much of the light from the point F into a plane (25) through the point F. Application to lamps for indicating the survivors at sea of shipwrecks or air crashes, said lamp being suitable for equipping life jackets on board aircraft.

Abstract: A lighting system for providing aesthetic and energy efficient lighting, for building interiors and exterior lighting, includes lighting fixtures including a high intensity discharge lamp and a novel lens. The lens is formed as a dropped square pyramid with four triangular lower panels and four generally vertical side walls. Prisms on the inner and outer faces of the lens produce a higher luminous intensity at an angle of about 30.degree. to 50.degree. than at nadir and project light at higher angles toward the corners of the lens than perpendicular to the sides of the lens, thereby producing a generally square, widespread light distribution pattern. The lens cuts off high angle light (with respect to nadir), thereby reducing glare.

Abstract: A photoflash unit having one or more flash lamps, and a transparent cover in front of the flash lamps which is provided with elongated light-refractive prisms in front of each flash lamp so as to refract directly radiated light from the lamp when flashed in a more frontward direction and into the area to be illuminated. Prisms may be provided on both sides of the cover.

Abstract: A backlight for an electrooptic display, such as a liquid crystal display, serves to diffuse and distribute light from a point source, such as an incandescent bulb, over a broad, flat thin area providing backlighting for the display. The backlight employs a transparent light transmitting member with a slot or recess for the light source, wrapped in a thin transluscent sheet which covers both front and back surfaces and the edges to serve as a transflector.

Abstract: A luminaire useful in illuminating a task area and having particular application for roadway lighting includes a monochromatic light source which is preferably a low pressure sodium lamp which can be an elongated tubular light source disposed within a housing defined by a reflector having a configured reflection surface to principally control light distribution along the length of the roadway with the lamp being at least partially surrounded and in a specific embodiment totally surrounded by a cylindrical tube acting as a substrate for a multilayer interference mirror to principally control light distribution across or transverse to the roadway. This combination of elements, in particular cooperation with their specific configurations, provides a predetermined light pattern on a task surface such as the example roadway.

Abstract: A limited visibility signal device is disclosed which includes a housing, a source of illumination within the housing, a light directing lens at the outer end of the housing, and a light collimating arrangement between the source of illumination and light directing lens to intensify and directionally control light delivered to the light directing lens. The light directing lens includes an inner side provided with parallel lenticular elements extending thereacross and having first outer surface portions parallel to the lens axis and second outer surface portions of circular contour. The light directing lens further includes an outer side provided with parallel adjacent lenticular elements extending thereacross perpendicular to the elements on the inner side of the lens and alternate ones of which are of convex and concave contour with respect to the lens axis.

Abstract: A back-up lens for a stop, tail and signal lamp comprising a body of clear plastic material having an inner surface with dioptrics and catadioptrics thereon and an outer surface with cylindrical surfaces thereon.

Abstract: A lighting panel used to control locally unidirectional light is constructed from a plurality of light modifying elements that substantially control the distribution of light within a control range. Each element is disposed in the panel to receive the unidirectional light and has a surface means for critically reflecting the received light and for refracting the initially reflected light upon leaving the elements into the control range.