Abstract: An electronic lighting instrument features separate optical assemblies for flood lighting and spot lighting. The optical assemblies include primary, secondary, and tertiary optical elements. The housing of the instrument features a trilobal cross section and includes dust-and-moisture-sealed push buttons and lenses as part of the housing construction. Self-aligning assemblies to ensure correct electrical and mechanical assembly are provided. The housing also self-aligns with a mating docking station for recharging the instrument batteries in situ. The lighting instrument may be controlled by a microprocessor circuit to provide floodlight and spotlight beams and several operational states thereof depending on the need for illumination or signaling.

Abstract: An optical lens includes an array of lens units. Each lens unit includes a main body, a light diverging portion and a light converging portion. The main body includes a light incident surface and a light emitting surface opposite to the light incident surface. The light diverging portion is configured for expanding a light field along a first direction, and the light converging portion is configured for compressing a light field along a second direction. The light diverging portion and the light converging portion are both formed on one of the light incident surface and the light emitting surface.

Abstract: A backlight module (300) includes a plurality of illumination devices (100). Each of the illumination devices includes a light guide block (120) and a point light source (140) optically coupled with the light guide block. The light guide block includes a light exit surface (121), a bottom surface (123) opposite to the light exit surface, and a tapered portion (122) located between the light exit surface and the bottom surface. The bottom surface has a receiving hole (1232) formed therein. The tapered portion includes an outside surface (1221) and a prism array (1224) formed on the outside surface. The point light source is secured in the receiving hole. The plurality of illumination devices are joined with one another and the light exit surfaces of light guide blocks are substantially coplanar and whereby cooperatively constitute a light output surface of the backlight module.

Abstract: An LED light source includes an LED emitter and an encapsulant that at least partially surrounds the emitter. The encapsulant includes an inner lens and an outer lens, the inner lens having a refractive index less than, and in some cases about 70 to 80% of, the refractive index of the outer lens. The inner lens and outer lens can contact each other along a curved surface, and in some cases the inner lens is substantially plano-convex and the outer lens is meniscus. The inner lens produces a first virtual image of the emitter and the outer lens produces a second virtual image, and the first virtual image is disposed between the emitter and the second virtual image. The LED light source is capable of providing uniform illumination in a compact space.

Abstract: A light-emitting device (10) is arranged such that (x) R1 monotonically decreasing as ?1 increases, at least in a range of ?1<?/3, where an intersection of a light axis Z and an emission surface of a light-emitting element (1) is a reference point; ?1 is an angle between the light axis Z and a straight line that passes through the reference point and an arbitrary point on a light-incoming surface (2a), and R1 is a distance between the reference point and the arbitrary point on the light-incoming surface (2a); (y) R2 monotonically increasing as ?2 increases, at least in a range of ?2<?/3, where ?2 is an angle between the light axis Z and a straight line that passes through the reference point and an arbitrary point on a light-outgoing surface (2b), and R2 is a distance between the reference point and the arbitrary point on the light-outgoing surface (2b); and (z) A2 scatters light without generating uneven brightness on a liquid crystal display panel and has higher scattering ability that is obtained by

Abstract: An LED illumination lens can guide light from light emitting diodes (LEDs). The incident surface and transmission surface of the lens are a part of an elliptical shape. The present invention makes an optical lens which provides that light is refracted twice by the LED illumination lens, and the output light is more uniform and present a long elliptical output light. The curve surface of the transmission surface is selected from elliptical surfaces, rectangular surfaces, square shape surfaces, round surfaces and rectangular surfaces with a cut corner, and polygonal surfaces. An LED illumination lens serves to refract the light beam from the LED by the incident surface and then disperse by the transmission surface 12 into a slender and long elliptical light beam.

Abstract: A lamp cover includes an array of lenses. Each lens includes an incidence surface for receiving light, and an emitting surface opposite to the incidence surface. One of the incidence surface and the emitting surface is a convex surface. Each lens includes a first end and an opposite second end in a column direction, a third end and an opposite fourth end in a row direction. The lenses in each row, a thickness difference between the first end and the second end of each lens is greater than a thickness difference between the third end and the fourth end thereof. An illumination lamp is also provided in this invention.

Abstract: A light emitting diode (10) includes an LED chip (14) and an encapsulant (16) enclosing the LED chip. The LED chip has a light emitting surface (141), and the encapsulant has a light output surface (161) over the light emitting surface. The light output surface defines a plurality of annular, concentric grooves (163). Each groove is cooperatively enclosed by a first groove wall (165) and a second groove wall (166). The first groove wall is a portion of a circumferential side surface of a cone, and a conical tip of the cone is located on the light emitting surface of the LED chip.

Abstract: A light control film having a refractive index n and an uneven, irregular surface pattern provides a reasonable level of light diffusion without a glare problem provided, for any cross-section perpendicular to the base plane of the film, the average of absolute values of slope ?ave of a curve along the edge of the cross-section contoured by the rough surface pattern (profile curve) is at least 78-34 n degrees and no higher than 118-34 n degrees, or the average of absolute values of slope ?ave of a profile curve to the length L1 of a straight line defined by the intersection of the base plane and the cross-section satisfies the following formula (3) or (4) for substantially all cross-sections.

Abstract: An optical element is disclosed, for receiving relatively narrow light from a planar light-emitting diode (LED) source, and for redistributing the light into a relatively wide range of output angles that span a full 360 degrees. The element may be used to retrofit existing fixtures that were originally designed for incandescent bulbs with LED-based light sources that have similar emission profiles. The element is small enough so that it may be packaged along with an LED module and its control electronics in the volume envelope of an incandescent light bulb. An exemplary element is a single, transparent, rotationally-symmetric lens that has a batwing shape in cross-section, extending angularly away from a longitudinal axis. The lens also includes a variety of curved, straight, specular and optionally diffuse portions on its longitudinal and transverse faces, all of which cause a variety of internal and external reflections, refractions, and optionally scattering.

Abstract: An illuminating lens includes: a light entrance surface through which light emitted from a light source enters the lens; and a light exit surface through which the light that has entered the lens exits the lens. The light exit surface has: a concave portion intersecting the optical axis; and a convex portion provided around the concave portion to extend continuously from the concave portion. The light exit surface is formed in a shape such that a curvature C of micro-segments of the light exit surface in a cross section including the optical axis has a maximum value at a position outward from the midpoint of the convex portion.

Abstract: Light redirecting film comprises a thin optically transparent substrate having a pattern of individual optical elements of well defined shape on or in at least one surface that are quite small relative to the length and width of the surface. At least some of the optical elements have at least one flat surface and at least one curved surface and may intersect each other to a greater extent on the curved surface than on the flat surface to increase the relative percentage of flat surface area to curved surface area of the intersecting optical elements.

Abstract: One embodiment of a light-emitting diode (LED) optic comprises a light-transmitting element having a plurality of segments, each segment associated with an optical axis and comprising a linearly projected cross-section. For each segment of the light-transmitting element, the LED optic comprises at least one LED positioned such that a central light-emitting axis of the at least one LED is angled at about 0° relative to the optical axis associated with that segment. In one embodiment, the about 0° has a tolerance of ±10°. Each segment of the light-transmitting element comprises a light-entering surface, a light-exiting surface and a light-reflecting surface. In one embodiment, for each segment the at least one LED comprises a plurality of LEDs.

Abstract: A light control plate 30A of the present invention is disposed in front of a surface light source 20 that emits, in a predetermined direction, parallel light Fi having a substantially uniform luminance distribution. The light control plate 30A has a light incidence surface 30a, at which there are provided optical path control sections 31A of concave and/or convex cross-sectional shape, and a planar light exit surface 30b. The surface of the optical path control sections 31A comprises first to M-th planar portions 32A1 to 32AM. The inclination angles ?1 to ?M and pitch ratios L1 to LM of each planer portion are specified in such a manner that the parallel light Fi can be spread within an exit angle range ??max to ?max relative to the predetermined direction, to exit as light having a substantially uniform luminance angular distribution within the exit angle range.

Abstract: Illumination lenses (1806, 1902, 2002, 2100, 2200, 2300, 2400, 2500, 2600, 2700, 2800, 3006, 3100) having surfaces shaped according to given differential equations in order to distribute light in a highly controlled manner with minimum reflection losses are provided. Both primary lenses and secondary lenses are provided. The secondary lenses include outer surfaces that are defined as loci of constant optical distance from an origin at which a light source is located. Versions are provided of both the primary and secondary lenses having Total Internal Reflection (TIR) wings. These are useful in the case that narrower distributions of light are required. A method of refining the shape of the lenses to obtain more obtain lenses that produce better fidelity ideal light distributions is also provided.

Abstract: A portable luminaire includes an optical module, a power source and a housing. The optical module has at least one light emitting diode (LED) that emits light with a wide divergence, a non-imaging optical element and a transparent window. The non-imaging optical element (NIO) has a refractive member located around a LED optical axis and a total internal reflection member located around the refractive member. The refractive member and the total internal reflection member are integrated in a single transparent element having a mutual focal point. The NIO element collects a significant amount of light emitted by the LED with wide divergence located at the focal point to compress the collected light with high efficiency into a required pattern with a generally different angular distribution in a horizontal plane and a vertical plane, and to direct the compressed light outside of the luminaire.

Abstract: A lens array includes a first lens group with rows of first lenses having first optical surfaces, a second lens group with rows of second lenses having second optical surfaces, and a reference plane. Each first and second lenses extend along a first axis. The second lenses are disposed at two sides of the first lens group along a second axis perpendicular to the first axis. An optical axis of the second optical surface is perpendicular to the first and second axis. An optical axis of the first optical surface is perpendicular to the first axis and has an angle larger than 0 degree and smaller than 6 degrees with the optical axis of the second optical surface. The reference plane perpendicular to the second axis passes through the first lens group. A normal vector of each first optical surface on the optical axis points away from the reference plane.

Abstract: Various embodiments described herein comprise array of light emitting diodes and a cylindrical lens having front and rear curved surfaces. The cylindrical lens is disposed to receive light from the light emitting diodes and to redistribute the light. The cylindrical lens is located no more than about 8 inches distance from the front an illumination target, which may for example, comprise products on shelves in a refrigerator. The front and rear surfaces of the cylindrical lens are shaped to provide substantially uniform illumination across the target.

Abstract: An exterior automotive lamp may be formed with LED light sources by efficiently using the available light. The LEDs are arranged in an array to illuminate a central lens to produce the horizontal spread from the central portion of the LED beam. Meanwhile a reflector gathers the more disperse side-emitted portion of the LED beam and directs that light as an outer sheath to form a supplementary portion of the beam. The lamp efficiently provides a beam that may be adapted for highbeam, lowbeam, fog, or signal purposes.

Abstract: An apparatus and method is characterized by providing an optical transfer function between a predetermined illuminated surface pattern, such as a street light pattern, and a predetermined energy distribution pattern of a light source, such as that from an LED. A lens is formed having a shape defined by the optical transfer function. The optical transfer function is derived by generating an energy distribution pattern using the predetermined energy distribution pattern of the light source. Then the projection of the energy distribution pattern onto the illuminated surface is generated. The projection is then compared to the predetermined illuminated surface pattern to determine if it acceptably matches. The process continues reiteratively until an acceptable match is achieved.

Abstract: An LED light shaping device and illumination system are provided. According to one embodiment, a light shaping lens is configured to shape light emitted from a light source and direct the light on a display panel for projection. The light shaping lens comprises a light input surface configured to receive light emitted from the light source a reflective surface configured to reflect at least part of the light received by the light source; and a light output surface having a first curvature in a first direction and a second curvature in a second direction, wherein the light output surface is configured to emit the light that is received by the light input surface and reflected by the reflective surface, and wherein the first curvature and the second curvature are configured to shape the light such that the emitted light has an oval cross section.

Abstract: A light emitting device comprises: an LED chip mounted in a recess formed in a mounting substrate; a wavelength converting member that is disposed so as to cover the recess and the edge area around the recess and that is excited by light emitted from the LED chip to emit light of a wavelength different from an excitation wavelength; and an emission control member disposed at a light output side of the wavelength converting member so as to allow emission of light coming from an area of the wavelength converting member that corresponds to the recess and to prevent emission of light coming from an area of the wavelength converting member that corresponds to the edge area around the recess. This can prevent variations in color between light emitted from the central part of the wavelength converting member and light emitted from the part of the wavelength converting member that is located on the edge area around the recess of the mounting substrate, thereby reducing unevenness of color on the irradiation surface.

Abstract: An optical module for projecting a light beam comprises a solid body of transparent material into which a light source is sunk and which is delimited by an annular surface and by a central surface, and a substantially annular reflecting surface arranged around the solid body. The central and annular surfaces are suitable for receiving respective distinct portions of the luminous flux produced by the source. The reflecting surface may have a reflecting coating or may form part of a transparent body, in which case it works by total internal reflection. The reflecting surface reflects a portion of luminous flux refracted by the annular surface and shapes the flux into a predetermined distribution of luminous intensity about the principal axis. The annular surface is designed in a manner such as to reduce the overall thickness of the module by moving the refracted ray away from the principal axis.

Abstract: An optical element is configured for use in conjunction with a directional light source such as an LED to form an illuminator. The optical element includes a light entry surface, a reflector and an emission surface. Each of the light entry, reflector and emission surfaces are surfaces of revolution defined by revolving straight or curved lines about an axis of revolution. The light entry, reflector and emission surfaces are configured to produce a radiation pattern from the illuminator that is collimated in a first direction and divergent or swept in a second direction perpendicular to the first direction.

Abstract: A lighting lens can sufficiently suppress unevenness color and improve light use efficiency. This light lens has: first incidence surface 20 that is orthogonal to the optical axis; second incidence surface 21 that expands the radius toward the light emitting element 8 side; total reflection surface 22 that expands the radius toward the emitting side; first emission surface 24 that mainly emits light incident on first incidence surface 21, toward illuminated surface 18; and second emission surface 25 that emits light incident on a second incidence surface, toward illuminated surface 18, and forms second emission surface 25 such that positive power in second emission surface 25 is weaker than positive power of first emission surface 24.

Abstract: A composite light guiding film module is disclosed, which includes: a light guiding film; a light diffusion structure comprising a plurality of micro concave lenses arranged in a first direction and a second direction to form a second dimensional array and the curvature of each concave lens and the junction of the concave lenses are not equal to zero; and a refraction element comprising at least one refraction structure, wherein light from a light source passes through the refraction element and is refracted to the light diffusion structure, and the light passing through the light diffusion structure is refracted into the light guiding film and then propagates in the light guiding film by total reflection.

Abstract: A lighting device includes at least a light source for emitting light rays and a guide for guiding light rays on a projection plane. The guide is formed by a lens presenting a cylindrical portion extending along an axis perpendicular to the projection plane, and at least one convex shaped surface extending at an extremity of the cylindrical portion. The convex shaped surface is adapted to direct a portion of the light rays emitted from the light source towards the projection plane. This enables to project the light towards a projection plane quasi parallel to the beam direction without using any guides on the projection plane itself.

Abstract: A light control film enabling improvement in front luminance, having appropriate light diffusing property and free from problems of interference pattern, glare etc. is provided. A light control film 10 having a rough surface as one surface and a substantially smooth surface as the other surface is constituted so that total light transmission of the film for lights entered from the smooth surface should be not more than 65%, total light transmission of the film for lights entered from the rough surface should be not less than 80%, as measured according to the measurement method defined in JIS K7361-1:1997, and a value obtained by subtracting the total light transmission for smooth surface incidence from the total light transmission for rough surface incidence should be not less than 30%.

Abstract: A light-influencing plate for a luminaire is made from transparent material and has wave progressions, which form a wavy structure, on one side and parallel light-damping or light-impermeable strips on the other side. The strips run transversely with respect to the wave progressions.

Abstract: A two-side illuminating lens body mainly projecting light from a light emitting device to two relative outer directions includes a base with a receiving slot having a downwards opening for receiving a lighting device. A concave arc for receiving the light emitting portion of the lighting device is formed above the receiving slot as a light incident side. On a top surface of the base, two symmetrical non-spherical protrusions are jointly arranged beside a center light axis. A concave curved surface is formed to a border of the two non-spherical protrusions. Two symmetrical awl laterals are formed on relative outer edges of the non-spherical protrusions. Through three different refracting types of the concave curved surface, non-spherical protrusions, and awl laterals, rays from the light emitting device will be gradually diffused away from the center light axis so that a double-side skew light distribution of illumination like a butterfly is projected.

Abstract: A two-side asymmetric light-shift illuminating lens body mainly projecting light from a light emitting device to two asymmetric relative outer directions includes a base having a receiving slot with a downwards opening for receiving a lighting device; a large non-spherical protrusion and a small a large non-spherical protrusion being arranged on two sides of a center light axis on a top surface of the base; a concave curved surface being formed to a border of the two non-spherical protrusions; a concave arc is formed above the receiving slot, outer edge of each non-spherical protrusion being formed with an awl lateral. The awl laterals are gradually narrowed along the projecting direction of the center light axis. An angle between a tangent line of the awl lateral and the center light axis is about 10 degrees.

Abstract: A light source emits light into a solid angle exceeding pi steradians with a known intensity distribution. An illumination lens has a first surface that receives at least 90% of the light of the known intensity distribution and has a shape that transforms the known intensity distribution into an intermediate intensity distribution within the transparent material of the lens. A second surface receives the intermediate intensity distribution and is shaped to transform the intermediate intensity distribution into a final intensity distribution that produces a prescribed illumination distribution upon a rectangular target zone. At least one of the shapes of the first and second surfaces is non-rotationally symmetric and is approximated by a super-ellipsoid.

Abstract: An apparatus and method is characterized by providing an optical transfer function between a predetermined illuminated surface pattern, such as a street light pattern, and a predetermined energy distribution pattern of a light source, such as that from an LED. A lens is formed having a shape defined by the optical transfer function. The optical transfer function is derived by generating an energy distribution pattern using the predetermined energy distribution pattern of the light source. Then the projection of the energy distribution pattern onto the illuminated surface is generated. The projection is then compared to the predetermined illuminated surface pattern to determine if it acceptably matches. The process continues reiteratively until an acceptable match is achieved.

Abstract: A secondary optical lens (105) includes a base plane (1054), a light incident surface (1053), a light emitting surface (1055), and two fasteners (1052). The light incident surface (1053) is a concave surface and is located in the center of the base plane (1054). The light emitting surface (1055) is formed by two partial spherical surfaces and a transition surface between the two partial spherical surfaces. The light emitting surface (1055) is connected to the base plane (1054) and defines the boundary of the base plane (1054). The two fasteners (1052) are respectively disposed at two edges of the base plane (1054) in a longitudinal direction.

Abstract: A light emitting device assembly includes: a light emitting device; and a light output member provided on the light emitting element and having an upper surface on which a curved part that outputs light from the light emitting device is provided, wherein a value of a x coordinate of a curved part center axis is a positive value, a locus of an edge of a curved part forms a circle or oval around the curved part center axis, light on a Z-axis output from an origin is output from the curved part at an angle ?0 (?0>0) formed with the Z-axis within a XZ-plane, and function F(?,??) expressed by F(?,??)=(??+????)/????(1) monotonously increases, takes the maximum value at ?=?0 (<0), and then, monotonously decreases as a value of ? increases from the minimum value.

Abstract: An optical module includes a point light source device and an optical lens. The point light source device generates light. The optical lens includes an inner curved surface and an outer curved surface. The inner curved surface has a first roughly ellipsoidal shape having a first major axis and a first minor axis that is substantially perpendicular to the first major axis. The outer curved surface has a second roughly ellipsoidal shape having a second major axis that is substantially perpendicular to the first axis and the second minor axis that is substantially perpendicular to the second major axis. The light generated by the point light source device enters the optical lens through the inner curved surface and exits from the optical lens through the outer curved surface. Therefore, the number of optical modules used in a display device may be reduced to lower manufacturing cost thereof.

Abstract: By a convex lens arranged on an optical axis extending in a front and rear direction of a lamp unit, direct light from a light emitting element arranged rearward of the convex lens is deflected to emit so that the light is made to be parallel light in a vertical face and diffused light toward left and right sides in a horizontal face. An entire region of a left side lens region of the convex lens is constituted as upper deflecting regions for deflecting light to a direction upward with respect to a direction of light of a right side lens region. Light emitted to the front side by transmitting the respective upper deflecting regions is made to be light directed upward from light emitted from the right side lens region to thereby form a laterally elongated light distribution pattern in which an upper end edge of a portion of being disposed on a left side relative to the optical axis is stepped up from an upper end edge of a portion thereof disposed on a right side.

Abstract: An optical sheet includes a substrate onto which light is incident, and a convex part protruded from the substrate by a predetermined thickness. A thickness of the convex part increases from an edge to a center thereof.

Abstract: An optical element including a unitary, non-circularly-symmetrical, piece of optically-transmissive material, which has at least first and second surfaces for concentrating light from a light source onto a linear target region, such that at least one of the first and second surfaces is curved, and such that a first portion of the light is concentrated onto the linear target region by reflection from the first surface, while a second portion of the light is concentrated onto the linear target region by refraction at the second surface.

Abstract: In one form, there is a luminaire for providing uniform color and brightness from multiple small light sources, which includes a shallow plate of transparent material having a first surface which is substantially flat, and a second surface which includes patterned planes acutely disposed to the first surface. Each second surface is adjacent to an entry face into which light from the multiple small light sources is projected into the plane.

Abstract: A back light module including a back plate, a light source and a bar lens is disclosed. The bar lens includes a top and a bottom center transparent surfaces, a right and a left top total internal reflection surfaces, a right and a left first emitting surfaces, a right and a left second emitting surfaces, a right and a left bottom total internal reflection surfaces and a right and a left bottom incident surfaces. The center bottom transparent surface is located between the top center transparent surface and the light source. The connecting sequence along the right of bar lens from top center transparent surface is the right top total internal reflection surface, the right first emitting surface, the right second emitting surface, right bottom total internal reflection surface, the right incident surface and the center bottom transparent surface. The connecting sequence on the left is similar to the right.

Abstract: An exemplary optical plate includes at least one transparent plate unit. The transparent plate unit includes a light output surface, a bottom surface, a plurality of spherical protrusions, a diffusion layer, and at least one lamp-receiving portion. The bottom surface is opposite to the light output surface. The diffusion layer is formed on the light output surface. The spherical protrusions are formed at the bottom surface. The lamp-receiving portion is defined in the bottom surface. A backlight module using the present optical plate is also provided.

Abstract: The present invention relates to a spread lens and a light emitting device assembly using the spread lens for miniaturization and improving a spread characteristic of a lens. In accordance with the present invention, a spread lens spreading light emitted from a light emitting device may include a first lens surface through which the emitted light from the light emitting device is inputted; a second lens surface spreading the light inputted through the first lens surface to an outside; refraction parts which extend between both side ends of each of the first and second lens surfaces, are formed in a concave-convex shape, and refract the emitted light from the light emitting device; and support parts which extend at both side ends of the second lens surface and separate the refraction parts and the light emitting device from each other.

Abstract: A lighting device can have a simple configuration which can be formed compactly in the direction of its optical axis in particular, and with a light weight. The lighting device can also have a functional, three-dimensional innovative appearance for the sake of enhanced merchantability and novelty. The lighting device can include a light source and a projection lens which is situated so that its source-side focus lies near the light source and its optical axis generally coincides with that of the light source. The projection lens can be a distribution control lens of convex form, having an exit surface shaped aspherically so that the direction of emission is continuously refracted into specified directions with respect to the angle of incidence from the focal position.

Abstract: A lens for use with a light emitting source is provided. The lens has a main body with a light-collecting face and a light-emitting face and which defines an optical axis extending through the centers of these two faces. A pocket for receiving light from the light source is defined in the light-collecting face by an inner axially-facing surface surrounded by an inner radially-facing surface. The inner axially-facing surface is concave and has a spherical shape. The inner radially-facing surface has a non-spherical, tapered shape and extends between the axially-facing surface and an open end of the pocket. A light assembly incorporating the lens includes a light-emitting diode.

Abstract: LED apparatus for illumination toward a preferential side, including a light emitter having at least one LED on a base, a primary lens positioned over the light emitter and having a central axis, and a secondary lens placed with an inner surface surrounding the primary lens. The secondary lens has a base-adjacent lower end defining a main plane substantially perpendicular to the central axis, and a compound outer lens surface with a middle-region reference point defining a reference axis parallel to the central axis.

Abstract: In a Fresnel lens which is made of a lens material whose refraction index is n, and focuses light beam from a light source at a specified radiation view angle ?, and has plural N pieces of circular lens surfaces arranged concentrically around a common optical axis, and plural circular rise surfaces arranged adjacent alternately between these lens surfaces, and two lens surfaces adjacent via at least one of the rise surfaces are concave surfaces, and tangent lines and at the intersecting point with the rise surfaces of the shape of a cross section passing through the optical axis of those lens surfaces intersect at the outside with respect to the optical axis, and when the angle formed between these tangent lines is defined as ?, a relational equation ???/(2 n N) stands.

Abstract: An illumination-redistribution lens comprising a thick aspheric lens collecting a high proportion of the luminous output of a compact LED with a quasi-hemispheric pattern. After receiving the highly nonuniform illuminance from the nearby LED, the lower surface refractively deflects these rays into a less diverging angular pattern that results in uniform illuminance on the upper surface of the lens, which itself is shaped so its distribution of slope angles refractively deflects the uniform illuminance distribution into an exiting beam that will produce uniform illuminance on a distant target, such as a table below a ceiling-mounted unit. When square-cut sections of such lenses are laterally arrayed to form a downlight, a uniform rectangular spot will be produced on the target.

Abstract: A lens for a light emitting diode is formed with a material having a refractive index of n, and the lens includes a base, a first curved circumferential surface extending from the base, a curved center-edge surface extending from the first curved circumferential surface, and a curved centermost surface extending from the curved center-edge surface. The base includes a groove for receiving a light emitting chip therein. In the lens, a distance from a center of the base to a point of the curved center-edge surface is always shorter than the radius of curvature for the point of the curved center-edge surface. The curved centermost surface has a concave shape with respect to the base.

Abstract: An optical device for collecting and distributing light from a quasi point light source which includes a planar light guide having surfaces through which optical axes are periodically spaced. There is at least one quasi point light source, the optical axis of each being coincident with the optical axes of the surfaces. There is also at least one optical element depressed within the edges or adjacent surfaces of the light guide at least partially rotated about the optical axis, and having a focal point at the quasi point light source.