Abstract: A guide plate has a back face provided with a great number of micro-reflectors which has a guide portion and a conversion output portion including a valley. The conversion output portion reflects twice input light P at inner slopes, generating inner output light Q directed obliquely as to be distant from an incidence end face. Inner output light Q is inner-incident to a slope of projection row PR on an emission face, with the result that some of the inner-incident light becomes a direct escaping light and much of the other reaches the emission face again after travelling along various paths. At the second time or later chances of escaping, an actual escaping occurs to generate an indirect escaping light. A mixed emission suitably blended of the direct and indirect light is directed to directions, which are modified to directions around a roughly frontal direction by prism sheet PS before being supplied to a LCD panel or the like to be illuminated.

Abstract: 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 ?5/?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 ?5/?1 decreases gradually according to increasing of ?1, where ?1 is an emission angle of any light at being emitted from the light emitting element, and ?5 is an emission angle of that light of ?1 at then being emitted from the light control emission face of the light flux control member.

Abstract: Provided are an illumination device and a lens employed in the device for controlling light travelling direction, the device being capable of illuminating brightly and uniformly a certain limited region (region-to-be-illuminated) corresponding to an object such as subject for photography. The illumination device emits light H coming from a light emitting element (point-like light source) employing a LED as a light emitting source via the lens. A light control emission face of the lens emits light (rays), which is included in light H introduced into the lens through an incidence face thereof and travelling within the lens to the light control emission face without undergoing inner-reflection at any surface of the light control emission face, as illumination light.

Abstract: Light from light emitting element enters into a flux control member through a recess on an inner face of the light flux control member, being emitted from an emission control face (outer face). At least so far as light falls within a half-intensity-angular-range, the light satisfies Condition 1 (?5/?1)>1 except for light in the vicinity of a normal direction of the emission control face) and Condition 2 (Value of ?5/?1>1 gets smaller gradually with increasing of ?1). It is noted that ?1, ?5 are angles made at being inner-incident to the emission control face and at being emitting from the same, respectively. The emission control face has a planar outline shape which is anisotropic around optical axis L, thereby causing value of ?5 /?1 to have a change depending on direction angle ? around optical axis L, with the result that highly uniform light is supplied to a required anisotropic irradiation range.

Abstract: A surface light source device for illuminating a displaying member of a display comprises a light guide plate and primary light source. Primary light enters into a first guiding portion through an end face (incidence face) thereof extending in an extending direction, then inner-propagating and entering into any second guiding portion gradually meantime. A major part thereof is inner-reflected by an inner-reflection face (first side face) to be directed to a guiding-emitting-portion, then being outputted from an emission face gradually. The first side face makes a sharp angle ? with respect to the extending direction at a portion connected to the guiding-emitting-portion. Second guiding portion has a second side face which is located on a side nearer to the incidence face and makes a sharp angle greater than ? at a portion connected to the first guiding portion.

Abstract: Provided is a light emitting device having an inner-propagation-medium which caused directivity-to-optical-axis-direction to be relaxed. Light of a LED travels in the inner-propagation-medium, being emitted from an inside area of or outside area in a lens surface directly or via an inclined reflection face. A light emitter provides an output light having an intensity profile with a half-intensity-angular-range not greater than 20°, which expresses directivity of the output light. The outside area in the lens surface performs a traveling-direction-expanding-function which is not only relatively intensive as compared that performed by the inside area in the lens surface, and but also relatively intensive as compared that performed in an imaginary case where the outside area gives a planar surface perpendicular to an optical axis. The half-intensity-angular-range of the intensity profile of the light emitting device is not smaller than 30° with respect to the optical axis and not greater than 70°.

Abstract: Primary light is directed to a light path control plate from at least one point-like light source. The light path control plate has an inner face on which projection-like transmission-reflection portions and curved-for-refraction portions are alternately formed along a leaving-direction from an optical axis direction of the point-like light source, wherein each transmission-reflection portion is composed of a transmission face permitting primary light to transmit through the transmission face and a reflection face which reflects the transmitted light as to bring changed light paths directed to an outer face of the light path control plate while each curved-for-refraction portion refracts primary light as to bring changed light paths directed to the outer face of the light path control plate. First light reaching the outer face via the transmission-reflection portions and second light reaching the outer face via the curved-for-refraction portions are generated from primary light.

Abstract: Illumination device/surface light source device provides an increased and uniformalized emission brightness. A plurality of fluorescent lamps are disposed in parallel with each other at a certain interval between a reflection sheet and light flux control member. A back face of the light flux control member is provided with recesses and curved surfaces connected thereto at locations corresponding to those of the fluorescent lamps. Each recess consists of first and second light entering surfaces. Each curved surface consists of third and forth light entering surfaces. A bulging configuration is formed around boundary between each recess and each curved surface. The first light entering surface causes light coming to areas corresponding to the fluorescent lamps, included in the light reaching a light diffusing member, to diverge smoothly.

Abstract: A LCD panel LP of LCD 2 is illuminated by a surface light source device of side light type 1 for backlighting. The surface light source device 1 comprises a plurality of sets each of which consists of a primary light source and a guide plate. When a fluorescent lamp 11A is turned on, illumination light LA is introduced into the guide plate 7A and then emitted from an emission face 7AO to be transferred to another guide plate 7B. A back face 7AR is provided with projection rows which prevent illumination light from being diverged toward right and left directions as viewed from an incidence end face 7A. Light transferred to the guide plate 7B is emitted from an emission face 7BO to directions inclined forward (LA1). A prism sheet 9 converts this into output illumination light LA2, which illuminates the LCD panel LP through a light diffusion sheet 10.

Abstract: A surface light source device for illuminating a displaying member of a display comprises a light guide plate and primary light source. Primary light enters into a first guiding portion through an end face (incidence face) thereof extending in an extending direction, then inner-propagating and entering into any second guiding portion gradually meantime. A major part thereof is inner-reflected by an inner-reflection face (first side face) to be directed to a guiding-emitting-portion, then being outputted from an emission face gradually. The first side face makes a sharp angle ? with respect to the extending direction at a portion connected to the guiding-emitting-portion. Second guiding portion has a second side face which is located on a side nearer to the incidence face and makes a sharp angle greater than ? at a portion connected to the first guiding portion.

Abstract: 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.

Abstract: An increased emission brightness provides a clear image display. Light from luminescent lamp 10 travels into light guide plate 2 through incidence face 3, being emitted from emission face 4 for irradiating LCD panel 5. Back face 7 of light guide plate 2 serves as light gathering function surfaces 14, 15 reflecting light as to gather the light around a normal direction of emission face 4 which provides an emission promotion surface having first and second slopes 17 and 18 for promoting the light introduce through incidence face 3, the first slopes 17 being configurated as to gently decrease thickness of light guide plate 2 with an increasing distance from incidence face 3 while second slopes 18 are configurated as to sharply increase thickness of light guide plate 2 with an increasing distance from thinner-plate-thickness-side end portions of slopes 17.

Abstract: A guide plate 30 has a back face 34 provided with a great number of micro-reflectors 90 which has a guide portion and a conversion output portion including a valley. The conversion output portion reflects twice input light P at inner slopes, generating inner output light Q directed obliquely as to be distant from an incidence end face 32. Inner output light Q is inner-incident to a slope of projection row PR on an emission face 33, with the result that some of the inner-incident light becomes a direct escaping light and much of the other reaches the emission face 33 again after travelling along various paths. At the second time or later chances of escaping, an actual escaping occurs to generate an indirect escaping light. A mixed emission suitably blended of the direct and indirect light is directed to directions, which are modified to directions around a roughly frontal direction by prism sheet PS before being supplied to a LCD panel or the like to be illuminated.

Abstract: 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 ?5/?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 ?5/?1 decreases gradually according to increasing of ?1, where ?1 is an emission angle of any light at being emitted from the light emitting element, and ?5 is an emission angle of that light of ?1 at then being emitted from the light control emission face of the light flux control member.

Abstract: A guide plate 30 has a back face 34 provided with a great number of micro-reflectors 90 which has a guide portion and a conversion output portion including a valley. The conversion output portion reflects twice input light P at inner slopes, generating inner output light Q directed obliquely as to be distant from an incidence end face 32. Inner output light Q is inner-incident to a slope of projection row PR on an emission face 33, with the result that some of the inner-incident light becomes a direct escaping light and much of the other reaches the emission face 33 again after travelling along various paths. At the second time or later chances of escaping, an actual escaping occurs to generate an indirect escaping light. A mixed emission suitably blended of the direct and indirect light is directed to directions, which are modified to directions around a roughly frontal direction by prism sheet PS before being supplied to a LCD panel or the like to be illuminated.

Abstract: Light flux control member 4 receives light from at least one LED 5, letting the light be emitted from emission face 4b. Light flux control member 4 is provided with recess 7 corresponding to each LED 5. Each recess 7 is configured so as to satisfy the following Conditions 1 and 2 for at least light which is emitted toward within a half-intensity-angular-range from corresponding LED 5. Condition 1: Relation ?5/?1>1 is satisfied except for light emitted toward within an angular-neighbourhood of a normal direction with respect to emission face 4b; Condition 2; Value of ?5/?1 decreases gradually according to increasing of ?1; (where ?1 is an emission angle of any light at being emitted from LED 5; and ?5 is an emission angle of that light at then being emitted from emission face 4b.) If a plurality of LEDs are employed, differences in emitting color among individual LEDs are made less conspicuous and uniform illumination free from uneven brightness is realizable.

Abstract: A LCD comprises a surface light source device of side light type for auxiliary lighting. A fluorescent lamp is turned on to supply primary light to be introduced into a guide plate. A back face (upper face) of the guide plate provides a light control face including an emission promoting surface to promote emission from an illumination output face (lower face). The illumination output face provides a specular face without scattering power. Illumination light L2 introduced into the guide plate escapes gradually from the back face and the illumination output face on the way of propagation.

Abstract: LEDs 5 serving as light sources are arranged so as to face an incidence surface 4 of a light guide plate 3. Light emitted from the LEDs 5 is incident on the incidence surface 4 of the light guide plate 3 to enter the light guide plate 3 to be propagated through the light guide plate 3. When the angle of incidence of the light on an emission surface 6 of the light guide plate 3 is a critical angle or less while the light is propagated, the light leaves the emission surface 6. On at least one of the emission surface 6 of the light guide plate 6 and a surface 10 opposite to the emission surface 6 of the light guide plate 6, a large number of prism protrusions 12 extending in parallel to such a direction that a distance from the incidence surface 4 increases are formed along the incidence surface 4. A side-face side portion 10b of the prism protrusions 12 is formed so as to have a height gradually decreasing as a distance from the incidence surface 4 decreases.

Abstract: A surface light source device is provided with a primary light source and light guide plate. The light guide plate has an incidence side face opposite to which the primary light source employing LEDs or the like is disposed, an emission face for emitting light, which has been incident to the incidence side face, during the propagation process, and a back face oppositely located with respect to the emission face. The back face may be provided with a plurality of prism projections running generally vertically to the incidence side face. The primary light source has an effective light emitting surface provided with length L in a thickness direction of the light guide plate, which is not smaller than thickness t of the light guide plate at the incidence side face. This causes primary light to be incident to the incidence side face as to cover from an upper edge to lower edge thereof, preventing dark parts from being generated.

Abstract: Provided are surface light source devices and LCDs having isotropic and wide viewing angles. A surface light source device for illuminating an LCD comprises a light guide plate hiving a back face provided with a great number of micro-reflectors. Light beams P1, P2 representing an inner input light are inner-reflected by first and then second inner reflection faces or in inverse order, respectively to become a first and second inner output lights Q1 and Q2 which are non-parallel to each other, providing an emission having angular intensity characteristics showing two peaks. Peak splitting of the emission is dissolved by a light diffusion sheet disposed along an emission face of the light guide plate, causing an LCD panel to be illuminated by an isotropic and wide-view-angled illumination output light.