Abstract: A planar light source device 200 includes a light source 10 and a reflection member 30. The light source 10 emits a light beam 10a having directivity. The reflection member 30 has a box shape including a single bottom-plate part 30e, side-plate parts 30a, 30b, 30c and 30d connected to the bottom-plate part 30e, and an opening part 30f facing the bottom-plate part 30e. The box shape has inner surfaces which are reflection surfaces. The bottom-plate part 30e has a quadrilateral shape including two facing short sides and two facing long sides. The light beam 10a enters an inside of the box shape of the reflection member 30 through a side of the side-plate part 30a connected to the short side of the bottom-plate part 30e, travels in a direction of the long side of the bottom-plate part 30e while being reflected at the side-plate parts 30c and 30d connected to the long sides of the bottom-plate part 30e, and is emitted through the opening part 30f.

Abstract: A planar light source device 200 includes a light source 10 and a reflection member 30. The light source 10 emits a light beam 10a having directivity. The reflection member 30 has a box shape including a single bottom-plate part 30e, side-plate parts 30a, 30b, 30c and 30d connected to the bottom-plate part 30e, and an opening part 30f facing the bottom-plate part 30e. The box shape has inner surfaces which are reflection surfaces. The bottom-plate part 30e has a quadrilateral shape including two facing short sides and two facing long sides. The light beam 10a enters an inside of the box shape of the reflection member 30 through a side of the side-plate part 30a connected to the short side of the bottom-plate part 30e, travels in a direction of the long side of the bottom-plate part 30e while being reflected at the side-plate parts 30c and 30d connected to the long sides of the bottom-plate part 30e, and is emitted through the opening part 30f.

Abstract: An angular intensity distribution shaping member includes a first surface for receiving a light beam emitted from a light source, the first surface having a length in a width direction that is longer than that in a thickness direction; second surfaces forming a plate-shaped light path on which the light beam incident from the first surface propagates by total reflection, the second surfaces including at least one adjustment surface for spreading a full angle of an angular intensity distribution, in the width direction, of the light beam incident from the first surface so that the full angle becomes wider than that of the angular intensity distribution of the light beam just after emission from the light source; and a third surface through which the light beam exits, the full angle of its angular intensity distribution in the width direction having been widened by the at least one adjustment surface.

Abstract: The planar light source device 200 includes a laser light source 7, a light guide rod 4, and a reflection unit 6. The laser light source 7 emits laser light 71. The light guide rod 4 having a rod shape has a light incident surface 41 at the end portion of rod shape in its longitudinal direction, and converts the laser light 71 entering through the light incident surface 41 into liner-shaped light. The reflection unit 6 has a box-like shape including a base plate 61, side plates 62, 63, 64, 65 being connected to the base plate 61, and an opening 66 facing the base plate 61, and the inner surfaces of base plate 61 and side plates 62, 63, 64, 65 configure reflection surfaces. The light guide rod 4 is disposed at a portion enclosed by the reflection surface of base plate 61 and the reflection surfaces of side plates 62, 63, 64, 65.

Abstract: A surface light source device includes a surface light-emitting light-guiding unit; an LED light source disposed at an outside position on a side of a direction of the light incident surface; a plurality of laser light sources disposed at an outside position on a side of a direction of a rear surface of the surface light-emitting light-guiding unit; and a laser-light-ray guiding unit arranged on a side of a rear surface of the surface light-emitting light-guiding unit. The laser-light-ray guiding unit guides the laser light rays emitted from the laser light sources so that the laser light rays enter through a light incident end surface, travel in a direction opposite to a direction in which the LED light source emits the LED light ray, and thereafter are reflected by a light bending part to enter through the light incident surface of the surface light-emitting light-guiding unit.

Abstract: A light intensity distribution conversion element has a light incident surface, a light emission surface, and total reflection surfaces. Light having directivity enters the light incident surface. The light emission surface has a curved surface portion of a concave shape with respect to an emitting direction of the light, for broadening an angular intensity distribution of the light. The total reflection surfaces are near or are adjacent to the curved surface portion, are slanted against the emitting direction of the light, and totally reflect the light. The light reflected by the total reflection surfaces is emitted from the curved surface portion.

Abstract: A planar light source device includes a first light source for emitting a first light ray having a punctate spatial luminance distribution; a second light source for emitting a second light ray; a first spatial luminance distribution conversion portion for changing the first light ray to a linear spatial luminance distribution; a second spatial luminance distribution conversion portion for changing a spatial luminance distribution of the first and second light rays to a planar spatial luminance distribution; wherein the first light ray is a laser light; the second light ray has a divergence angle larger than the divergence angle of the first light ray when the first light ray is emitted from the first light source; and a slow-axis direction of the first light ray entering the second spatial luminance distribution conversion portion is parallel to an outgoing direction of the planar light.

Abstract: An objective is to obtain a backlight in which a decrease in brightness at a peripheral portion associated with the change of viewing distance is reduced.

Abstract: An angular intensity distribution shaping member includes a first surface for receiving a light beam emitted from a light source, the first surface having a length in a width direction that is longer than that in a thickness direction; second surfaces forming a plate-shaped light path on which the light beam incident from the first surface propagates by total reflection, the second surfaces including at least one adjustment surface for spreading a full angle of an angular intensity distribution, in the width direction, of the light beam incident from the first surface so that the full angle becomes wider than that of the angular intensity distribution of the light beam just after emission from the light source; and a third surface through which the light beam exits, the full angle of its angular intensity distribution in the width direction having been widened by the at least one adjustment surface.

Abstract: A surface light source device includes a surface light-emitting light-guiding unit; an LED light source disposed at an outside position on a side of a direction of the light incident surface; a plurality of laser light sources disposed at an outside position on a side of a direction of a rear surface of the surface light-emitting light-guiding unit; and a laser-light-ray guiding unit arranged on a side of a rear surface of the surface light-emitting light-guiding unit. The laser-light-ray guiding unit guides the laser light rays emitted from the laser light sources so that the laser light rays enter through a light incident end surface, travel in a direction opposite to a direction in which the LED light source emits the LED light ray, and thereafter are reflected by a light bending part to enter through the light incident surface of the surface light-emitting light-guiding unit.

Abstract: A planar light source device includes a first light source for emitting a first light ray having a punctate spatial luminance distribution; a second light source for emitting a second light ray; a first spatial luminance distribution conversion portion for changing the first light ray to a linear spatial luminance distribution; a second spatial luminance distribution conversion portion for changing a spatial luminance distribution of the first and second light rays to a planar spatial luminance distribution; wherein the first light ray is a laser light; the second light ray has a divergence angle larger than the divergence angle of the first light ray when the first light ray is emitted from the first light source; and a slow-axis direction of the first light ray entering the second spatial luminance distribution conversion portion is parallel to an outgoing direction of the planar light.

Abstract: A liquid crystal display device has a first backlight unit and a second backlight unit. The first backlight unit includes a first optical member that transmits light incident from the second backlight unit, converts light output from a light source to light having a narrow-angle directional distribution, and radiates the converted light toward the rear surface of the liquid crystal display panel. The second backlight unit includes a second optical member that converts light output from a light source to light having a wide-angle directional distribution, and radiates the converted light toward the rear surface of the liquid crystal display panel.