Asymmetric illumination light guide plate design

Abstract

A lighting assembly (100) is provided that includes a plurality of light sources (102), a light guide plate (106), a back reflector (110), a front collector (114), and a plurality of microstructures (124). The light source is configured to generate light and is disposed on the PCB (118). The light guide plate (106) is arranged to receive light generated by the light source (102). The light guide plate (106) and the plurality of light sources (102) are separated by a gap (108). The back reflector (110) is disposed along a first surface (112) of the light guide plate (106). The front collector (114) is disposed below a second surface (116) of the light guide plate (106) opposite the first surface (112). The front collector (114) is also arranged across a gap (108) separating the light guide plate (106) from the plurality of light sources (102). The microstructures (124) are arranged on the first surface (112) of the light guide plate (106) and arranged in a pattern to provide an asymmetric light distribution (200).

Description

Technical Field

[0001] The present disclosure generally relates to light guide plate designs for providing asymmetric illumination. Background Art

[0002] Comfort is a key factor in achieving human-centric lighting in both indoor and outdoor applications. Applications that require asymmetric lighting, such as outdoor urban or road scenes, currently rely on lens solutions. These lens solutions typically use dot-shaped lenses or peanut-shaped lenses to achieve asymmetric light distribution, resulting in pixelation on the emitting surface. Therefore, when the emitting surface of the luminaire is viewed directly, especially when viewed from the direction of peak intensity, the emitted light is accompanied by significant glare, causing discomfort to the viewer. This discomfort can be a significant safety hazard in outdoor applications such as road lighting.

[0003] Alternatively, some current solutions utilize light guides, rather than lenses. These light guides typically utilize conventional techniques, such as laser dots printed on a plate. Such techniques result in a high degree of non-uniformity, limiting their use in applications requiring uniform light. Thus, there is a need in the art for an optical design (e.g., a light guide) to achieve side-lit asymmetric lighting with improved uniformity and reduced glare and pixelation, such as in outdoor or urban-type luminaires. Summary of the invention

[0004] The present disclosure relates to a lighting assembly that can produce asymmetric light with improved uniformity and reduced glare and pixelation compared to previous optical designs. The lighting assembly can be used in outdoor and urban applications, such as for illuminating roads, sidewalks and other outdoor infrastructure. Typically, the lighting assembly includes a plurality of light sources (such as light emitting diodes (LEDs)), a printed circuit board (PCB), a light guide, a back reflector and a front collector. The LED is arranged on the PCB. The light guide is arranged in close proximity to the LED so that the light guide receives the light generated by the LED. The light guide is separated from the LED by a gap of air or other materials having a different refractive index from the light guide. The light guide can be linear, circular or any other suitable shape. If the light guide is circular, the PCB can be flexible (i.e., FPCB). The FPCB can be arranged around the periphery of the circular light guide in a full circle or semicircular configuration. The applicant has recognized and understood that the light guide design with a three-dimensional texture as described herein can provide asymmetric lighting with improved uniformity and a light window with reduced or no pixelation on its surface when viewed from any viewing angle.

[0005] As described herein, the back reflector is arranged above the top surface of the light guide plate so that it covers the LED. In one example, the light generated by the LED travels through the light guide plate, reflects away from the back reflector, and leaves the lighting assembly through the bottom surface of the light guide plate. The LED light then travels to a road or sidewalk positioned below the lighting assembly. The back reflector can be a specular reflector, a semi-specular reflector, or a non-specular reflector. Further, the back reflector may include one or more subassemblies. In other examples, the side reflector is arranged on the third surface of the light guide plate and is substantially perpendicular to the back reflector. The side reflector is arranged relative to the LED and the PCB so that it faces the LED from the entire length of the light guide plate.

[0006] The front collector is configured to prevent light from escaping the lighting assembly through the gap between the LED and the light guide plate. The front collector is positioned below the bottom surface of the light guide plate so that it covers the LED. The front collector is used to reduce light spots and / or brightness from the LED.

[0007] In order to provide asymmetric light, the top surface of the light guide plate is textured with a pattern of three-dimensional microstructures. In some instances, each of the microstructures may be a symmetrical elliptical shape. In some instances, one or more of the microstructures are filled with a material having a different refractive index from the light guide plate, and different microstructures may be filled with different materials having different refractive indices. In some instances, one or more of the microstructures are empty or unoccupied, that is, there is no material. In addition, one or more of these microstructures may have a rough surface, such as having a roughness average (Ra) between about 0.1 and 20 microns. These microstructures may be arranged in a variety of different patterns on the top surface, such as a circle or a hexagon or any suitable alternative shape. The circular structure may include a plurality of concentric rings, each ring including a portion of the plurality of microstructures. In addition, the size and rotation angle of each microstructure may be a function of the position of the microstructure on the top surface. For example, a microstructure near the center of the top surface may be significantly larger than a microstructure located near the outer edge of the top surface. Similarly, a microstructure near the edge of the top surface may have a larger rotation angle than a microstructure located near the center of the top surface. The pattern, arrangement, size and rotation angle of the microstructures are used to configure the directional angle of light distribution provided by the optical component.

[0008] In general, in one aspect, a lighting assembly is provided. The lighting assembly includes a plurality of light sources. The plurality of light sources are configured to generate light. In one example, the plurality of light sources are disposed on a PCB.

[0009] The lighting assembly also includes a light guide plate. The light guide plate is arranged to receive light generated by the plurality of light sources. The light guide plate is separated from the plurality of light sources by a gap. According to an example, the light guide plate is substantially circular or non-circular. Further with respect to this example, the plurality of light sources are arranged in a circular or non-circular arrangement around the light guide plate.

[0010] The lighting assembly further comprises a back reflector. The back reflector is arranged along the first surface of the light guide plate. According to an example, the back reflector is a specular reflector or a semi-specular reflector.

[0011] The lighting assembly further includes a front collector. The front collector is disposed below a second surface of the light guide plate opposite to the first surface. The front collector is also arranged to span a gap separating the light guide plate from a plurality of light sources. According to an example, the front collector is configured to reflect light.

[0012] According to an example, the lighting assembly further includes a side reflector. The side reflector is disposed adjacent to the back reflector and the third surface of the light guide plate.

[0013] According to an example, the lighting assembly further comprises a plurality of microstructures. The plurality of microstructures are disposed on the first surface of the light guide plate. In an example, each of the plurality of microstructures is defined by a rotationally symmetric or non-rotationally symmetric shape. Further, the rotationally or non-rotationally symmetric shape of a first microstructure in the plurality of microstructures may be scaled or stretched in at least one dimension relative to the rotationally or non-rotationally symmetric shape of a second microstructure in the plurality of microstructures.

[0014] According to one example, one or more dimensions of one of the plurality of microstructures correspond to the position of one of the plurality of microstructures on the first surface of the light guide plate. In another example, the rotation angle of one of the plurality of microstructures corresponds to the position of one of the plurality of microstructures on the first surface of the light guide plate.

[0015] According to an example, the plurality of microstructures are arranged in a pattern comprising a plurality of concentric rings. The lighting assembly produces an asymmetric light distribution. A first microstructure of a first concentric ring of the plurality of concentric rings may be arranged at a different rotation angle than a second microstructure of a first concentric ring of the plurality of concentric rings.

[0016] According to an example, the plurality of microstructures are arranged in a hexagonal pattern. The lighting assembly can generate an asymmetric light distribution. The first microstructures in the hexagonal pattern can be arranged at a different rotation angle than the second microstructures in the hexagonal pattern.

[0017] It should be understood that all combinations of the foregoing concepts and additional concepts discussed in more detail below (provided such concepts are not mutually inconsistent) are contemplated as being part of the inventive subject matter disclosed herein. In particular, all combinations of claimed subject matter appearing at the end of this disclosure are contemplated as being part of the inventive subject matter disclosed herein. It should also be understood that terminology appearing in any disclosure that is expressly adopted herein and that may also be incorporated by reference should be accorded a meaning most consistent with the specific concepts disclosed herein.

[0018] These and other aspects of the various embodiments will be apparent from and elucidated with reference to the embodiments described hereinafter. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In the drawings, like reference characters generally refer to like parts throughout the different views. Also, the drawings are not necessarily drawn to scale, emphasis instead generally being placed upon illustrating the principles of the various embodiments.

[0020] Figure 1 is a cross-sectional view of a lighting assembly according to aspects of the present disclosure.

[0021] Figure 2 is a cross-sectional view of a lighting assembly for providing asymmetric light distribution according to aspects of the present disclosure.

[0022] Figure 3A is a perspective view of a light guide plate having a microstructure located at the center of the light guide plate according to aspects of the present disclosure.

[0023] Figure 3B According to aspects of the present disclosure, Figure 3A The x- and z-axis dimensions of the microstructure.

[0024] Figure 3C According to aspects of the present disclosure, Figure 3A The y-axis and z-axis dimensions of the microstructure.

[0025] Figure 4A is a perspective view of a light guide plate having microstructures offset from the center of the light guide plate according to aspects of the present disclosure.

[0026] Figure 4B According to aspects of the present disclosure, Figure 4A The x- and z-axis dimensions of the microstructure.

[0027] Figure 4C According to aspects of the present disclosure, Figure 4A The y-axis and z-axis dimensions of the microstructure.

[0028] Figure 5 A top view of a light guide plate having a plurality of microstructures arranged in a hexagonal pattern according to aspects of the present disclosure is shown.

[0029] Figure 6 A top view of a light guide plate having a plurality of microstructures arranged in a plurality of concentric rings according to aspects of the present disclosure is shown.

[0030] Figure 7 A cross-sectional view of a light guide plate having multiple microstructures with varying depths according to aspects of the present disclosure is shown.

[0031] Fig. 8A A top view of a lighting assembly according to aspects of the present disclosure is shown.

[0032] Figure 8B A bottom view of a lighting assembly according to aspects of the present disclosure is shown.

[0033] Fig. 9 An exploded view of a lighting assembly according to aspects of the present disclosure is shown.

[0034] Fig.10 The C-plane and gamma angles are shown according to aspects of the present disclosure.

[0035] Fig.11 An enlarged portion of a plurality of microstructures of a light guide plate according to aspects of the present disclosure is shown.

[0036] Fig.12 is a light distribution diagram of an exemplary lighting assembly according to aspects of the present disclosure.

[0037] Fig.13 is an illuminance diagram of an exemplary lighting assembly according to aspects of the present disclosure.

[0038] Fig.14 A top view of a non-circular light guide having a plurality of microstructures arranged in a hexagonal pattern according to aspects of the present disclosure is shown. DETAILED DESCRIPTION

[0039] The present disclosure relates to a lighting assembly that can produce asymmetric light with improved uniformity and reduced glare and pixelation compared to previous optical designs. The lighting assembly can be used in outdoor and urban applications, such as for illuminating roads, sidewalks and other outdoor infrastructure. Generally, the lighting assembly includes a plurality of light sources, such as light emitting diodes (LEDs), printed circuit boards (PCBs), light guides, back reflectors and front collectors. The LEDs are arranged on the PCB. The light guide is arranged in close proximity to the LEDs so that it receives light generated by the LEDs. The light guide is separated from the LEDs by a gap of air or other materials having a different refractive index from the light guide. The light guide can be linear, circular or any other suitable shape. The back reflector is arranged above the top surface of the light guide so that it can cover the LEDs. In another example, a side reflector is arranged on a side surface of the light guide. The side reflector is arranged opposite to the LEDs and the PCB so that the side reflector faces the LEDs. The front collector is configured to prevent light from escaping the lighting assembly via a gap between the LEDs and the light guide. The front collector is positioned below the bottom surface of the light guide so that it covers the LEDs. To provide asymmetric light, the top surface of the light guide is textured with a pattern of three-dimensional microstructures. In some examples, each of the microstructures may be symmetrically elliptical in shape. The microstructures may be arranged on the top surface in a variety of different patterns, such as radial or hexagonal.

[0040] Figure 1 1 is a cross-sectional view of a non-limiting example of a lighting assembly 100. The lighting assembly 100 includes a plurality of LEDs 102, a light guide plate 106, a back reflector 110, a front reflector 114, a PCB 118, and side reflectors 120. Figure 1 As shown, LED 102 emits light that exits from light guide plate 106. Light is shown for illustrative purposes, and only two potential paths of light 104a, 104b from LED 102 to light guide plate 106 are shown. One of ordinary skill in the art will appreciate that more potential paths are possible, additionally or alternatively. LED 102 is mounted to PCB 118. In some examples, PCB 118 is a flexible PCB (FPCB) configured to conform to the shape (circular, linear, etc.) of light guide plate 106.

[0041] The light guide plate 106 is arranged near the plurality of LEDs 102 and is configured to receive light 104 generated by the LEDs 102. As shown in subsequent figures, the light guide plate 106 may be substantially circular, substantially semicircular, substantially linear, or any other suitable shape. The light guide plate 106 may be defined by a first surface 112 defining a top of the light guide plate 106, a second surface 116 defining a bottom of the light guide plate 106, and a third surface 122 defining a side of the light guide plate 106 that is opposite the LEDs 102 and the PCB 118. The space between the LEDs 102 and the light guide plate 106 is defined by a gap 108. As will be shown in subsequent figures, the light guide plate 106 includes a plurality of three-dimensional microstructures 124 on the first surface 112. The microstructures 124 are configured to convert the light 104a, 104b emitted by the LEDs 102 into an asymmetric light pattern 200 (see Figure 2 ). The microstructure 124 is arranged on the first surface 112 to destroy the total internal reflection (TIR) ​​or adjust the TIR direction of the second surface 116 to achieve downward light output.

[0042] The back reflector 110 is disposed along the first surface 112 of the light guide plate 106. The back reflector 110 is configured to reflect the light 104a, 104b emitted by the LED 102 generally downward toward the second surface 116 of the light guide plate 106. The back reflector 110 can be specular, semi-specular, or non-specular. In some examples, the back reflector 110 can be a single component 110. In other instances, the back reflector 110 can be an assembly of two or more subcomponents depending on the overall mechanical and / or electrical design constraints. In a preferred example, the back reflector 110 covers the first surface 116 of the light guide plate 106, the gap 108, and the uppermost surface of the LED 102 to prevent the light 104 from escaping from the top of the lighting assembly 100. However, in other examples, the back reflector 110 can be separated from the PCB 118 by a second gap. If the back reflector 110 is made of a metal material, the second gap may be required. To prevent the light 104 from escaping through the second gap, an additional reflector, such as a white non-metallic reflector, may be used to cover the gap. Figure 1 The example further includes a side reflector 120 configured to prevent light 104 from escaping from the side of the lighting assembly 100 defined by the third surface 122 of the light guide plate 106. Therefore, the side reflector 120 can be arranged adjacent to the third surface 122 of the light guide plate 106 and the back reflector 110.

[0043] The front collector 114 is arranged below the second surface 116 and opposite to the first surface 112. The front collector 114 is also arranged to span the gap 108 separating the LED 102 from the light guide plate 106. In other words, the distance between the first end and the second end of the front collector 114 is greater than the space within the gap 108. The front collector 114 prevents the light 104 from escaping the lighting assembly 100 via the gap 108. Therefore, the front collector 114 hides light spots or excessive brightness caused by the light 104 escaping through the gap 108.

[0044] Light 104a illustrates one possible path that can be taken within lighting assembly 100. Light 104a is emitted by one LED 102 and is directed downward. Front collector 114 then reflects light 104a upward. Back reflector 110 then reflects light 104a downward and out of lighting assembly 100 via second surface 116 of light guide plate 106.

[0045] Similarly, light 104b illustrates another possible path that light may take within lighting assembly 100. Light 104b is emitted by one of LEDs 102 and is directed perpendicular to LED 102. Side reflector 120 then reflects light 104b downward and out of lighting assembly 100 via second surface 116 of light guide 106. After reflecting off side reflector 120, light 104b may be considered to travel around the optical axis of one of LEDs 102.

[0046] Figure 2 is another cross-sectional view of a non-limiting example of a lighting assembly 100 . Figure 2 An asymmetric light distribution 200 produced by the light assembly 100 due to the microstructures 124 disposed on the first surface 112 of the light guide plate 106 is shown.

[0047] Figure 3A Light guide plate 106 is shown having a single three-dimensional microstructure 124 disposed on first surface 112 for illustrative purposes. Position 134 of microstructure 124 is defined according to light guide plate coordinate system 150. Position 134 of microstructure 124 is origin O of light guide plate coordinate system 150 in this embodiment.

[0048] Figure 3B and 3C The dimensions of the microstructure 124 in the x-axis, y-axis, and z-axis directions are defined according to the texture coordinate system 175. In this example, the microstructure 124 has a width 126a in the x-axis direction, a length 126b in the y-axis direction, and a depth 126c in the z-axis direction. Specifically, Figure 3B and 3C An example is shown in which a is greater than c but less than b. Other values ​​of a, b, and c may be selected depending on the desired characteristics of the asymmetric light distribution 200 provided by the lighting assembly 100 (see Figure 2 ).

[0049] exist Figure 3A In some embodiments, the microstructure 124 is reflection symmetric about its x-axis, y-axis, and z-axis. In other embodiments, the microstructure 124 may be rotationally symmetric about a rotation angle. In other examples, the microstructure 124 may be completely asymmetric. In some embodiments, the microstructure 124 is filled with a material having a different refractive index than the light guide plate 106. In some embodiments, the microstructure 124 is not filled with a material having a different refractive index and is empty or unoccupied. In addition, the microstructure 124 may have a rough surface, such as having a roughness average (Ra) between about 0.1 microns and 20 microns.

[0050] Figure 4A Light guide plate 106 is shown with a single three-dimensional microstructure 124, where location 134 is offset from origin O of light guide plate coordinate system 150. Microstructure 124 may also be defined by a rotation angle 128 relative to the x-axis of light guide plate coordinate system 150. Figure 4B and 4C The dimensions 126a, 126b, 126c of the microstructure are defined in the x-, y-, and z-directions, respectively, according to a texture coordinate system 175. In these examples, the dimensions 126a, 126b, 126c and the rotation angle 128 are determined according to the position 134 of the microstructure 124.

[0051] exist Figures 4A-4C In the example of g , Y g , Z g ), and the coordinates of the texture coordinate system 175 can be expressed as (X t , Y t , Z t ).like Figure 4B and 4C As shown, microstructure 124 has a width 126a of a*A in the x-axis direction, a length 126b of b*B in the y-axis direction, and a depth 126c of c*C in the z-axis direction. In some examples, a, b, and c can be fixed values ​​for a certain shape (e.g., an oval), and coefficients A, B, and C can be functions of the position 134 of the individual microstructure 124. In one example, A can be determined according to the following equation:

[0052] A(X g ,Y g )=A1+(A g1 *X g )+(A g2 *Y g )+(A g3 *Xg 2 )+(A g4 *Y g 2 ) (1)

[0053] In the example of equation 1, A1, A g1 , A g2 , A g3 and A g4 It can be a fixed value within a limited value range (such as [-20, 20]). Similarly, B and C can be defined according to the following equations:

[0054] B(X g ,Y g )=B1+(B g1 *X g )+(B g2 *Y g )+(B g3 *X g 2 )+(B g4 *Y g 2 ) (2)

[0055] C(X g ,Y g )=C1+(C g1 *X g )+(C g2 *Y g )+(C g3 *X g 2 )+(C g4 *Y g 2 ) (3)

[0056] Similar to A1, A g1 , A g2 , A g3 and A g4 , B1, B g1 , B g2 , B g3 , B g4 , C1, C g1 , C g2 , C g3 and C g4 A variable can be a fixed value within a defined range of values ​​(although this fixed value and value range will likely differ from A fixed value).

[0057] Furthermore, the rotation angle 128 may be defined according to the following equation:

[0058] θ(X g,Y g )=θ1+(θ g1 *X g )+(θ g2 *Y g )+(θ g3 *X g 2 )+(θ g4 *Y g 2 ) (4).

[0059] As in the above example, variables θ1, θ g1 ,θ g2 ,θ g3 and θ g4 It can be a fixed value within a limited value range (such as [-90, 90]).

[0060] Figure 5 1 shows a top view of a circular light guide 106 having a plurality of microstructures 124 arranged in a generally hexagonal pattern 132 to produce an asymmetric light distribution 200. In some examples, the size 126 and rotation angle 128 of the microstructures 124 in the generally hexagonal pattern 132 may vary based on their location 134 on the light guide 106. For example, while Figure 5 Each of the microstructures 124 shown in FIG. 1 is identical, but one or more of the microstructures 124 may differ in size or rotation in the x-axis, y-axis, and z-axis. Figure 5 In the example of g4 =1.8, B1=C1=1, C g1 = -5 and θ g2 =80, and all other fixed values ​​are set to 0. Therefore, the center column of microstructures 124 is arranged at a rotation angle 128 of approximately zero degrees. The microstructures 124 of the two columns adjacent to the center column are arranged at a rotation angle 128 slightly greater than zero degrees. Therefore, the rotation angle 128 of the microstructure 124 is proportional to the distance of the position 134 of the microstructure 124 relative to the center column. Figure 5 In FIG. 1 , the semicircular LEDs 102 are arranged around the outer edge of the light guide plate 106, and Figure 6 In FIG. 1 , the fully circular LEDs 102 are arranged around the outer edge of the light guide plate 106 .

[0061] Figure 6 1 shows a top view of another circular light guide plate 106 having a plurality of microstructures 124 arranged in a pattern comprising a plurality of concentric rings 130 to produce a symmetrical light distribution. Figure 6There are six microstructures 124 surrounding the central microstructure. These six microstructures 124 form a concentric ring. Figure 6 As shown, there are 13 microstructures 124 around the first six microstructures to form another concentric ring, and so on outward. Figure 6 In the exemplary pattern shown, four concentric rings are formed around a central microstructure at the center. In some examples, the microstructures 124 of each of the concentric rings 130 may vary in size 126 and rotation angle 128 based on their location 134 on the light guide plate 106. Figure 6 As shown, the microstructures 124 of each concentric ring 130 have approximately the same x-axis, y-axis, and z-axis dimensions. However, within each concentric ring 130, each microstructure has a unique rotation angle 128. In addition, the x-axis, y-axis, and z-axis dimensions of the microstructures 124 of one concentric ring 130 are different from the x-axis, y-axis, and z-axis dimensions of the microstructures from another concentric ring 130. In addition, each concentric ring 130 includes a different number of microstructures 124. Figure 6 In the example of g3 =A g4 =1.8, B1=C1=1, C g1 = -5 and θ g1 =30, and all other fixed values ​​are set to 0. A full circle of LEDs 102 is arranged around the outer edge of the light guide plate 106 .

[0062] Figure 7 1 shows a cross-sectional view of a light guide plate 106 having a plurality of microstructures 124 arranged on a first surface 112 of the light guide plate 106. Figure 7 As shown, each row of microstructures 124 has a unique depth 126c. Figure 7 The microstructure 124 shown at the top has the deepest depth and is Figure 7 The bottom microstructure has the shallowest depth, and the depth of each microstructure therebetween is between the deepest depth and the shallowest depth.

[0063] Fig. 8A is a top view of the lighting assembly 100, and Figure 8B is a bottom view of the same lighting assembly 100 . Fig. 8A A circular top frame assembly 136 is shown. In other examples, the top frame assembly 136 can be a non-circular shape, such as a rectangular or linear shape. The top frame assembly 136 can include mounting holes to mount the lighting assembly 100 to a lamp post, lamp pole, or other outdoor lighting structure via screws, bolts, or other suitable means. Figure 8B A bottom frame assembly 138 is shown. Fig. 9As shown in FIG. 1 , the bottom frame assembly 138 is mechanically coupled to the top frame assembly 136 to enclose other components of the light assembly 100 . Further, the bottom frame assembly 138 is hollow, thereby exposing the second (bottom) surface 116 of the light guide plate 106 .

[0064] Fig. 9 An exploded view of a non-limiting example of a lighting assembly 100 is shown. Fig. 9 As shown, the lighting assembly 100 includes a top frame assembly 136, a back reflector 110, a plurality of LEDs 102 arranged on a flexible semicircular strip of a PCB 118, a light guide 106 having a plurality of microstructures 124, an O-ring 140, a front collector 114, and a bottom frame assembly 138. The O-ring 140 is used to protect the components of the lighting assembly 100 arranged within the top frame assembly 136 and the bottom frame assembly 138 from environmental conditions.

[0065] Fig.10 An exemplary spatial light distribution of the light assembly contemplated herein is shown. Optically speaking, the spatial light distribution shown is defined by a C-plane 142 and a gamma angle G. A normal N is oriented perpendicular to the emitting surface 116 of the light guide 106. The normal N may also be an imaginary line passing through the center of the luminaire. Any angle relative to the normal N is defined as the gamma angle G. The C-plane 142 passes through the normal N and is arranged relative to the second (bottom) emitting surface 116 of the light guide 106. In other words, the C-plane 142 is arranged along the longer direction of the application or luminaire. Any angle relative to the C-plane 142 is defined by the angle C of the C-plane, and the angle C of the C-plane is referred to as the amount of rotation about the normal N. The asymmetric light distribution 200 (see Figure 2 ) is defined by the angle C of the C-plane and the gamma angle G. Then, the intensity I of the asymmetric light distribution 200 may be defined as a function of the angle C of the C-plane and the gamma angle G, for example, I(C, γ).

[0066] Fig.11 144a, 144b, 144c of the plurality of microstructures 124a, 124b, 124c of the light guide plate 106 are shown. Specifically, these enlarged portions illustrate how the microstructures 124 vary in both size 126 and rotation angle 128. In this manner, Fig.11 The light guide plate 106 can be regarded as Figure 5 The size 126 and rotation angle 128 of each microstructure 124 are defined based on equations (1)-(4) discussed herein, which are based on the position 134 of each microstructure 124 and a plurality of predefined coefficients (A1, A g1In the first portion 144a, the microstructures 124a are arranged at an angle of about 65 degrees relative to the normal line N (see Fig.10 ). In the second portion 144b, the microstructures 124b are arranged substantially parallel to the normal N. In the third portion 144c, the microstructures 124c are arranged at an angle of approximately 65 degrees to the normal N. In this example, the coefficients for configuring each microstructure 124 are designed to achieve an asymmetric light distribution 200 for road lighting (see Figure 2 ). Road lighting requires that the lighting assembly 100 utilizes a forward illumination field defined by 1.5 times the mounting height and a peak intensity when the C-plane angle C is 65 degrees to illuminate a spacing defined by six times the mounting height of the lighting assembly 100. Figures 4A-4C Microstructure 124 and equation 1-4, when b is greater than a, θ g2 is about 65 degrees. Therefore, the microstructures 124a, 124c are oriented in the direction of the peak intensity.

[0067] Fig.12 yes Fig.11 The light distribution diagram of the exemplary light guide plate 106 is shown in FIG. Fig.12 In , B represents a blue region, G represents a green region, R1 and R2 represent a red region, and P1, P2, and P3 represent a purple region. Further for this example, Fig.13 is corresponding to Fig.11 2. The illuminance diagram of the exemplary light guide plate 106 is shown in FIG. The illuminance diagram shows the exemplary light guide plate 106 as producing a batwing-shaped asymmetric light distribution 200 on the road. In this example, the lighting assembly 100 is mounted at a height of 6 meters, spaced 36 meters apart from other lights, and mounted at a front distance of 7.6 meters. This configuration results in an average illuminance (E ave ) and minimum illumination (E min ) is 2.33, and the maximum illumination (E max ) and E min The ratio is 4.22. ave :E min Ratio and 11 E max :E min Compared with traditional light guide plate solutions, Fig.11 The light guide plate 106 is a significant improvement over existing light guide plates used in road lighting applications.

[0068] Fig.14 A variation of the light guide plate 106 is shown, wherein the light guide plate 106 is non-circular, rather than circular. Fig.14 In FIG. 1 , the plurality of microstructures 124 are arranged in a semi-hexagonal pattern 132 .

[0069] All definitions, as defined and used herein, should be understood to be governed by dictionary definitions, definitions in documents incorporated by reference, and / or ordinary meanings of the defined terms.

[0070] Unless explicitly stated to the contrary, the indefinite articles "a" and "an" as used herein in the specification and claims should be understood to mean "at least one".

[0071] As used herein in the specification and claims, the phrase "and / or" should be understood to mean "either or both" of the elements so combined, i.e., elements that are present in combination in some cases and separately in other cases. Multiple elements listed with "and / or" should be interpreted in the same manner, i.e., "one or more" of the elements so combined. Optionally, other elements may be present in addition to the elements specifically identified by the "and / or" clause, whether related or unrelated to those elements specifically identified.

[0072] As used herein in the specification and claims, "or" should be understood to have the same meaning as "and / or" as defined above. For example, when separating the items in the list, "or" or "and / or" should be interpreted as inclusive, i.e. including at least one of a plurality of elements or a list of elements, but also including more than one, and optionally including other unlisted items. Only the terms that are clearly indicated in the opposite direction, such as "only one" or "just one", or "consisting of..." (when used in the claims) will refer to including just one element in a plurality of elements or a list of elements. Usually, when there is an exclusive term (such as "any one", "one of", "only one" or "just one") in front, the term "or" as used herein should only be interpreted as indicating an exclusive alternative (that is, "one or another but not two").

[0073] As used herein in the specification and claims, the phrase "at least one" referring to a list of one or more elements should be understood to mean at least one element selected from any one element or multiple elements in the list of elements, but not necessarily including at least one of each element specifically listed in the list of elements, and not excluding any combination of elements in the list of elements. This definition also allows that elements other than the specifically named elements in the list of elements to which the phrase "at least one" refers may optionally be present, whether related or unrelated to those specifically named elements.

[0074] It should also be understood that in any method claimed herein that includes more than one step or action, the order of the method actions or steps is not necessarily limited to the order in which the method steps or actions are described unless explicitly stated to the contrary.

[0075] In the claims, as well as in the foregoing description, all transitional phrases such as "comprising," "including," "carrying," "having," "containing," "involving," "maintaining," "containing," etc. shall be understood to be open-ended, i.e., meaning including but not limited to. Only the transitional phrases "consisting of" and "consisting essentially of shall be closed or semi-closed transitional phrases, respectively.

[0076] Other implementations are within the scope of the following claims and other claims to which the applicant may attach.

[0077] Although different examples have been described and shown herein, it will be easy for a person of ordinary skill in the art to think of various other devices and / or structures for performing the functions described herein and / or obtaining results and / or one or more advantages, and such changes and / or modifications are each considered to be within the scope of the examples described herein. More generally, it will be easy for a person skilled in the art to understand that all parameters, dimensions, materials and configurations described herein are intended to be exemplary, and actual parameters, dimensions, materials and / or configurations will depend on the specific application using the teaching. It will be recognized or clear that many equivalent forms of the specific examples described herein are determined using no more than routine experiments. Therefore, it should be understood that the aforementioned examples are presented only by way of example, and within the scope of the appended claims and their equivalents, examples may be implemented in a manner different from that specifically described and claimed. Examples of the present disclosure relate to the features, systems, articles, materials, kits, and / or methods of each individual described herein. In addition, any combination of two or more such features, systems, articles, materials, kits and / or methods (if these features, systems, articles, materials, kits and / or methods are not mutually exclusive) is included within the scope of the present disclosure.

Claims

1. A lighting assembly (100), comprising: a plurality of light sources (102) configured to generate light (104); a light guide plate (106) arranged to receive light (104) generated by the plurality of light sources (102), wherein the light guide plate (106) and the plurality of light sources (102) are separated by a gap (108); a back reflector (110) disposed along a first surface (112) of the light guide plate (106); a front collector (114) disposed below a second surface (116) of the light guide plate (106) opposite the first surface (112) and spanning the gap (108) separating the light guide plate (106) from the plurality of light sources (102); a plurality of microstructures (108) arranged on the first surface (112) of the light guide plate (106); and The lighting assembly (100) generates an asymmetric light distribution (200).

2. The lighting assembly (100) of claim 1, wherein the plurality of light sources (102) are arranged on a printed circuit board (PCB) (118).

3. The lighting assembly (100) of claim 1, further comprising a side reflector (120) disposed adjacent to the back reflector (110) and the third surface (122) of the light guide plate (106).

4. The lighting assembly (100) of claim 1, wherein the back reflector (110) is a specular reflector or a semi-specular reflector.

5. The lighting assembly (100) of claim 1, wherein the front collector (114) is configured to reflect the light (104).

6. The lighting assembly (100) of claim 1, wherein the light guide plate (106) is substantially circular or non-circular.

7. The lighting assembly (100) of claim 1, wherein the plurality of light sources (102) are arranged in a circular or non-circular arrangement around the light guide plate (106).

8. The lighting assembly (100) of claim 1, wherein each of the plurality of microstructures (108) is defined by a rotationally symmetric or non-rotationally symmetric shape; and wherein the rotationally symmetric or non-rotationally symmetric shape of a first microstructure (108a) of the plurality of microstructures is scaled or stretched in at least one dimension relative to the rotationally symmetric or non-rotationally symmetric shape of a second microstructure (108b) of the plurality of microstructures (108).

9. The lighting assembly (100) of claim 1, wherein one or more dimensions (126) of one of the plurality of microstructures (108) corresponds to a location (134) of one of the plurality of microstructures (108) on the first surface (112) of the light guide plate (106).

10. The lighting assembly (100) of claim 1, wherein a rotation angle (128) of one of the plurality of microstructures (108) corresponds to a position (134) of one of the plurality of microstructures (108) on the first surface (112) of the light guide plate (106).

11. The lighting assembly (100) of claim 1, wherein the plurality of microstructures (108) are arranged in a pattern comprising a plurality of concentric rings (130).

12. The lighting assembly (100) of claim 11, wherein a first microstructure (108a) of a first concentric ring (130a) of the plurality of concentric rings (130) is arranged at a rotation angle (128) different from a second microstructure (108b) of the first concentric ring (130a) of the plurality of concentric rings (130).

13. The lighting assembly (100) of claim 1, wherein the plurality of microstructures (108) are arranged in a hexagonal pattern (132), and the lighting assembly (100) produces an asymmetric light distribution (200).

14. The lighting assembly (100) of claim 13, wherein the first microstructures (108a) of the hexagonal pattern (132) are arranged at a different rotation angle (128) than the second microstructures (108b) of the hexagonal pattern (132).

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