There is provided a surface light-emitting device capable of preventing an increase in power consumption even if the length of the light-emitting surface of the surface light-emitting device is greater than the width, and capable of emitting light uniformly without decreasing the brightness of the light-emitting surface nor increasing the height of the light guiding space. In the present surface light-emitting device, the incident plane (201) is one of two sides of the light guiding space (20) in opposition in the longitudinal direction. The light-transmitting plate (4) includes a diffusion filter (6) which covers a specific area of the surface of the light-transmitting plate (4) near the light source (3). The remaining area of the surface of the light-transmitting plate at a distance from the light source (3) is not covered with the diffusion filter (6). The diffusion filter (6) is formed of a laminate in which a plurality of diffuse transmission films are layered. The number of diffuse transmission film (6) layers is highest in the area closest to the light source (3) so that the light transmittance is increased as the distance from the light source (3) increases due to a decrease in the diffusion of light, and the number is gradually decreased as the distance from the light source (3) increases.

An illumination device for transmitting and/or distributing light with an extractor that extends distally into the interior of the light guide. The illumination device includes a hollow light guide including a wall having an inner surface and a structured outer side. The structured outer side includes a plurality of prisms defining grooves that extend along a length of the light guide. An extractor extends substantially along the length of the light guide and projects distally from the inner surface towards an interior of the light guide. The extractor is operative to cause light to be released through the wall of the light guide. A method of attaching the extractor is also disclosed.

A light guide luminaire includes a longitudinal housing having a center and an inner surface, and a light guide formed of at least two sections of optical lighting film arranged within the housing such that the shortest distance between the center of the housing and the inner surface of the housing is smaller than the radius of curvature of each section of optical lighting film. The light guide is slidably retained within the housing, and the housing and optical lighting film are arranged to define air gaps between the housing and optical lighting film. The luminaire may also include an extractor element extending radially inwardly from the inner surface of the housing for scattering light, and a back reflector for reflecting light back into the light guide. A joint member adapted to slidably receive end portions of the optical lighting film sections, the back reflector sections, and an extractor element is also disclosed.

Shaped refractive articles having compound curved surfaces enable a light source to provide substantially uniform illumination of a linear or planar target. The refractive articles can comprise an input edge or face and an output edge or face, the input edge or face having at least one shaped notch or cavity that can at least partially envelop a light source, wherein the notch or cavity has at least two oppositely signed curved portions shaped to provide substantially uniform illumination of a target by the source. The articles can also be optically coupled to and at least partially envelop a light source, and can have an output edge or surface having at least two oppositely signed curved portions shaped to provide substantially uniform illumination of a target region by the source. The shaped articles can be used in, for example, lighting devices, frontlights, backlights and electronic displays.