Description:FIELD OF THE DISCLOSURE

The present disclosure relates to the field of automobiles. In particular, the present disclosure relates to a lighting unit for a vehicle.

BACKGROUND

Generally, a vehicle such as a two-wheeler, a three-wheeler, or a four-wheeler is equipped with a lighting system having multiple light devices to illuminate a road ahead of the vehicle or to provide a visual indication of the presence of the vehicle. Some of the lighting systems include an emblem, or a logo adapted to be illuminated by the lighting system to enhance visibility, project modernity, indicate premium quality, and represent an identity of a brand of the vehicle. A light device of the lighting system generates light rays to illuminate the emblem to ensure that the emblem is visible even in low-light, dark environments, and from a distance.

Various types of light devices are known in the art. In one such art, light guides of the same shape as the illuminated letters are used and multiple LEDs are placed at the entire length of the illuminated letters. This increases the overall cost and requires more space as multiple LEDs are required to be placed.

However, a drawback associated with the existing lighting system is that more space is required to install the optical components such as a light source, a printed circuit board (PCB), a lens etc., of the existing lighting system. The space available in proximity to the emblem is constrained, so the installation of the existing lighting system becomes difficult. Due to the space constraints, the existing lighting system provides non-homogeneous light output. Currently, flexible light guides are commonly used in the lighting system to generate homogeneous light. The implementation of the flexible light guides increases the overall cost, and the flexible light guides are less durable. Further, the direct Light-emitting diodes (LEDs) are also used in combination with a diffusor to achieve homogeneous light. This also increases the overall cost of the lighting system.

Accordingly, there is an immense need to develop a lighting unit that overcomes one or more technical problems of the existing lighting systems.

SUMMARY

This summary is provided to introduce a selection of concepts, in a simplified format, that are further described in the detailed description of the disclosure. This summary is neither intended to identify key or essential inventive concepts of the disclosure and nor is it intended for determining the scope of the disclosure.

The present disclosure provides a lighting unit for a vehicle. The lighting unit may include a housing, a Printed Circuit Board (PCB), and a light guide. The housing includes a hollow compartment. The PCB may be disposed in the hollow compartment. Further, the PCB includes a light source mounted thereon to generate light rays. The light guide may include a collimator and a coupler. The collimator is adapted to generate collimated light rays from the light rays generated by the light source. The coupler is adapted to receive collimated light rays from the collimator and to reflect the collimated light rays as reflected light rays towards a periphery of the light guide. The periphery is adapted to transmit the received reflected light rays as transmitted light rays out from the light guide and a luminance from the transmitted light rays across the periphery is uniform.

Further, a light guide for a lighting unit is disclosed herein. The light guide may include a collimator, a coupler, a plurality of air pockets, and a chamfered profile. The collimator is adapted to generate collimated light rays from the light rays generated by a light source. The coupler is adapted to receive collimated light rays from the collimator and to reflect the collimated light rays as reflected light rays towards a periphery of the light guide. The plurality of air pockets is formed in the light guide at a predefined distance from the coupler. Each of the plurality of air pockets is adapted to receive reflected light rays and further reflects the received light rays as second reflected light rays towards the periphery of the light guide. The periphery is adapted to transmit the received reflected light rays and received second reflected light rays as transmitted light rays out from the light guide and a luminance from the transmitted light rays across the periphery is uniform. Further, the chamfered profile is formed on edges of the light guide. The chamfered profile includes a plurality of prismatic structure stripes to propagate the transmitted light rays uniformly.

As explained above, the coupler is adapted to receive collimated light rays from the collimator and to reflect the collimated light rays as reflected light rays towards the periphery of the light guide. The periphery transmits the received reflected light rays as transmitted light rays out from the light guide to generate the uniform luminance across the periphery of the light guide. Thus, the lighting unit generates a homogeneous light output which improves the overall illumination. Further, the plurality of prismatic structure stripes of the chamfered profile, propagates the transmitted light rays to generate better illumination.

To further clarify the advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which are illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects, and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:

Figure 1 illustrates a sectional schematic view of a lighting unit for a vehicle, according to an embodiment of the present disclosure;

Figure 2(a) illustrates a front view of a light guide of the lighting unit, according to an embodiment of the present disclosure;

Figure 2(b) illustrates a rear view of the light guide, according to an embodiment of the present disclosure;

Figure 2(c) illustrates a side view of the light guide, according to an embodiment of the present disclosure;

Figure 3 illustrates a perspective view of a coupler and a collimator of the lighting unit, according to an embodiment of the present disclosure;

Figure 4 illustrates a partial perspective view of the lighting guide depicting a propagation of light rays, according to an embodiment of the present disclosure;

Figure 5(a) illustrates the partial perspective view of the lighting guide depicting the propagation of the light rays through the collimator and the coupler, according to an embodiment of the present disclosure;

Figure 5(b) illustrates the partial perspective view of the lighting guide depicting the propagation of the light rays through a cone-shaped coupler, according to an embodiment of the present disclosure;

Figure 6 illustrates the partial perspective view of the lighting guide depicting the propagation of the light rays through a flower-shaped coupler, according to an embodiment of the present disclosure;

Figure 7(a) illustrates the partial perspective view of the lighting guide depicting the propagation of the light rays through the collimator, the coupler, and a plurality of air pockets, according to an embodiment of the present disclosure; and

Figure 7(b) illustrates a top view of the lighting guide depicting the propagation of the light rays through the collimator, the coupler, and a plurality of air pockets, according to an embodiment of the present disclosure.

Further, skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and may not have necessarily been drawn to scale. For example, the flow charts illustrate the method in terms of the most prominent steps involved to help to improve understanding of aspects of the present disclosure. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the embodiments of the present disclosure so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.

DETAILED DESCRIPTION

For the purpose of promoting an understanding of the principles of the disclosure, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended, such alterations and further modifications in the illustrated system, and such further applications of the principles of the disclosure as illustrated therein being contemplated as would normally occur to one skilled in the art to which the disclosure relates.

It will be understood by those skilled in the art that the foregoing general description and the following detailed description are explanatory of the disclosure and are not intended to be restrictive thereof.

Reference throughout this specification to “an aspect”, “another aspect” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. Thus, appearances of the phrase “in an embodiment”, “in another embodiment” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.

The terms "comprises", "comprising", or any other variations thereof, are intended to cover a nonexclusive inclusion, such that a process or method that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such process or method. Similarly, one or more devices or subsystems or elements or structures or components proceeded by "comprises... a" does not, without more constraints, preclude the existence of other devices or other sub-systems or other elements or other structures or other components or additional devices or additional sub-systems or additional elements or additional structures or additional components.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The system, methods, and examples provided herein are illustrative only and not intended to be limiting.

It should be understood at the outset that although illustrative implementations of the embodiments of the present disclosure are illustrated below, the present disclosure may be implemented using any number of techniques, whether currently known or in existence. The present disclosure should in no way be limited to the illustrative implementations, drawings, and techniques illustrated below, including the exemplary design and implementation illustrated and described herein, but may be modified within the scope of the appended claims along with their full scope of equivalents.

The term “some” as used herein is defined as “none, or one, or more than one, or all.” Accordingly, the terms “none,” “one,” “more than one,” “more than one, but not all” or “all” would all fall under the definition of “some.” The term “some embodiments” may refer to no embodiments or to one embodiment or to several embodiments or to all embodiments. Accordingly, the term “some embodiments” is defined as meaning “no embodiment, or one embodiment, or more than one embodiment, or all embodiments.”

The terminology and structure employed herein is for describing, teaching, and illuminating some embodiments and their specific features and elements and do not limit, restrict, or reduce the spirit and scope of the claims or their equivalents.

Reference is made herein to some “embodiments.” It should be understood that an embodiment is an example of a possible implementation of any features and/or elements presented in the attached claims. Some embodiments have been described for the purpose of illuminating one or more of the potential ways in which the specific features and/or elements of the attached claims fulfil the requirements of uniqueness, utility, and non-obviousness.

Use of the phrases and/or terms such as but not limited to “a first embodiment,” “a further embodiment,” “an alternate embodiment,” “one embodiment,” “an embodiment,” “multiple embodiments,” “some embodiments,” “other embodiments,” “further embodiment”, “furthermore embodiment”, “additional embodiment” or variants thereof do NOT necessarily refer to the same embodiments. Unless otherwise specified, one or more particular features and/or elements described in connection with one or more embodiments may be found in one embodiment, or may be found in more than one embodiment, or may be found in all embodiments, or may be found in no embodiments. Although one or more features and/or elements may be described herein in the context of only a single embodiment, or alternatively in the context of more than one embodiment, or further alternatively in the context of all embodiments, the features and/or elements may instead be provided separately or in any appropriate combination or not at all. Conversely, any features and/or elements described in the context of separate embodiments may alternatively be realized as existing together in the context of a single embodiment.

Embodiments of the present disclosure will be described below in detail with reference to the accompanying drawings.

Figure 1 illustrates a schematic view of a lighting unit 100 for a vehicle. Referring to Figure 1, the lighting unit 100 may be adapted to be equipped in the vehicle such as, but not limited to, a two-wheeler, a three-wheeler, and a four-wheeler. The lighting unit 100 may include a housing 102, a Printed Circuit Board (PCB) 104, a light source 106, an emblem 120, a plurality of air pockets 118 (shown in Figure 2(a)), and a light guide 108. The light guide 108 is adapted to receive the light rays from the light source 106 and further reflect the light rays in a uniform manner to generate a uniform luminance to illuminate the emblem 120.

The housing 102 includes a hollow compartment 102-1 adapted to accommodate the components of the lighting unit 100. In an embodiment, the housing 102 may be formed of a metallic material. In another embodiment, the housing 102 may be formed of a polymeric material. The PCB 104 may be disposed in the hollow compartment 102-1 of the housing 102. The PCB 104 may include the light source 106 mounted thereon to generate light rays 114.

The PCB 104 may be electrically connected to a power source of the vehicle to receive power. Further, the PCB 104 supplies the received power to the light source 106 to generate the light rays 114. The light source 106 may be positioned behind the light guide 108, such that the light source 106 may be aligned with the collimator 110 and the coupler 112 of the light guide 108. The light source 106 may be embodied as a Light-emitting diode (LED), without departing from the scope of the present disclosure. In an embodiment, the PCB 104 may include more than one light source 106 adapted to generate light rays 114.

The emblem 120 may be disposed in front of the light guide 108. The emblem 120 is adapted to be illuminated by light rays 114C (shown in Figure 5(a)) transmitted from the light guide 108. Herein, the light guide 108 transmits the light rays 114C towards the emblem 120, and the emblem 120 illuminates upon the receiving of the transmitted light rays 114C from the light guide 108. Further, the emblem 120 is adapted to be illuminated to represent the identity of a brand of the vehicle. The emblem 120 illuminates to project modernity and indicates premium quality. The lighting unit 100 illuminates the emblem 120 in such a manner that the emblem 120 is visible even in low-light, dark environments and from a distance.

In an embodiment, the emblem 120 may have a symmetrical shape representing the identity of the brand of the vehicle. In another embodiment, the emblem 120 may have an asymmetrical shape representing the identity of the brand of the vehicle. In one embodiment, the emblem 120 may be embodied as a logo formed on a lens, without departing from the scope of the present disclosure. In an embodiment, the emblem 120 may be formed of the metallic material. In another embodiment, the emblem 120 may be formed of the polymeric material.

Figure 2(a) illustrates a front view of the light guide 108 of the lighting unit 100, while Figure 2(b) illustrates a rear view of the light guide 108. Further, Figure 2(c) illustrates a side view of the light guide 108. Referring to Figures 1, 2(a), 2(b), and 2(c), the light guide 108 may include the collimator 110 and the coupler 112. In an embodiment, the light guide 108 may include more than one collimator 110 spaced at an equidistance. In an embodiment, the light guide 108 may include more than one coupler 112 positioned over the respective collimator 110 and spaced at an equidistance. In an embodiment, the light guide 108 may include more than one collimator 110 that spaced at unequal distance. In an embodiment, the light guide 108 may include more than one coupler 112 positioned over the respective collimator 110 and spaced at unequal distance.

The light guide 108 may include an opening adapted to accommodate the collimator 110 and the coupler 112. Herein, the coupler 112 may be aligned with the collimator 110. In an embodiment, the coupler 112 and the collimator 110 may be formed on a surface of the light guide 108 as an integrated part thereof. In another embodiment, the coupler 112 and the collimator 110 may be fastened on the surface of the light guide 108.

The light guide 108 may include a first surface 108-1 and a second surface 108-2 opposite to the first surface 108-1. In an embodiment as shown in Figure 2(a), the coupler 112 may be positioned on the first surface 108-1. In an embodiment as shown in Figure 2(b), the collimator 110 may be positioned on the second surface 108-2.

The collimator 110 is adapted to generate collimated light rays 114A from the light rays generated by the light source 104. The coupler 112 is adapted to receive collimated light rays 114A from the collimator 110 and to reflect the collimated light rays 114A (shown in Figure 5(a)) as reflected light rays 114B (shown in Figure 5(a)) towards a periphery of the light guide 108. The periphery is adapted to transmit the received reflected light rays 114B.

The periphery is adapted to transmit the received reflected light rays 114B as transmitted light rays 114C out from the light guide 108 and a luminance from the transmitted light rays 114C across the periphery is uniform. The light guide 108 may include a chamfered profile 122 formed on the edges of the light guide 108, as shown in Figure 2(b) and Figure 2(c). The chamfered profile 122 may have a plurality of prismatic structure stripes 124 adapted to propagate the transmitted light rays 114C. The light guide 108 may have any shape depending upon a shape of the emblem 120 placed in front of the light guide 108 to receive the transmitted light rays 114C. In an embodiment, the light guide 108 may be formed of a polymeric material.

The plurality of air pockets 118 may be formed in the light guide 108 at a predefined distance from the coupler 112. The plurality of air pockets 118 is designed to redirect the reflected light rays 114B towards the dark areas to remove hotspots which further improves homogeneity of the light rays. Each of the plurality of air pockets 118 is a cavity formed on the surface of the light guide 108. The plurality of air pockets 118 works on the principle of total internal reflection. As a result, the plurality of air pockets 118 does not require a special coating on the surface. Thus, the plurality of air pockets 118 is formed on the surface of the light guide 108 by a removal of material from the surface of the light guide 108 and creates such reflective air pockets 118.

Each of the plurality of air pockets 118 is adapted to receive the reflected light rays 114B from the coupler 112 and further reflects the received light rays 114B as second reflected light rays 114D towards the periphery of the light guide 108. The light guide 108 is adapted to transmit the received second reflected light rays 114D as the transmitted light rays 114C out from the light guide 108 and the luminance from the transmitted light rays 114C across the periphery is uniform.

Figure 3 illustrates a perspective view of the coupler 112 and the collimator 110 of the lighting unit 100. Referring to Figures 2(a), 2(b), and 3, the coupler 112 may include a chamfered periphery defining an outer wall 116 of the coupler 112. The coupler 112 is adapted to receive the collimated light rays 114A via the collimator 110, such that the collimated light rays 114A are collected and reflected towards the periphery of the light guide 108. The coupler 112 may be positioned at a predefined gap from the collimator 110, and the collimated light rays 114A propagate through the predefined gap and strike on the chamfered periphery to reflect towards the periphery of the light guide 108 to generate uniform luminance. In an embodiment, the coupler 112 may be positioned in front of the collimator 110.

In an embodiment, the chamfered periphery of the coupler 112 defines a conical surface adapted to receive the collimated light rays 114A via the collimator 110. Herein, the coupler 112 may have a cone shape with a half angle of 45 degrees, without departing from the scope of the present disclosure. In another embodiment, the chamfered periphery of the coupler 112 defines a plurality of profiles adapted to receive the collimated light rays 114A via the collimator 110. Herein, the coupler 112 may have a flower-shape as the plurality of profiles is joined together and forms a flower shape. The cone-shaped coupler 112 and the flower-shape coupler 112 are positioned on the light guide 108. In an embodiment, the flower-shaped coupler 112 may be formed on the surface of the light guide 108 in proximity to the edge of the light guide 108. In case, the coupler 112 is fastened to the light guide 108, the coupler 112 may be formed of the metallic material. On the other hand, in case, the coupler 112 is integrated to the light guide 108, both the light guide 108 and the coupler 112 may be formed of the polymeric material.

Figure 4 illustrates a partial perspective view of the light guide 108 depicting a propagation of the light rays 114C. Referring to Figures 1 and 4, the light rays generated by the light source 106, are received by the collimator 110. The collimator 110 generates the collimated light rays 114A from the light rays generated by the light source 106. Further, the coupler 112 receives the collimated light rays 114A from the collimator 110 and reflects the collimated light rays 114A as reflected light rays 114B towards a periphery of the light guide 108.

The periphery transmits the received reflected light rays 114B as transmitted light rays 114C out from the light guide 108. Herein, the transmitted light rays 114C have the same intensity. Thus, the luminance from the transmitted light rays 114C is uniform across the periphery of the light guide 108, as shown in Figure 4. This improves the overall illumination generated by the lighting unit 100, such that the emblem 120 illuminates effectively to improve the visibility.

Figure 5(a) illustrates a partial perspective view of the light guide 108 depicting the propagation of the light rays through the collimator 110 and the coupler 112 while Figure 5(b) illustrates a partial perspective view of the light guide 108 depicting the propagation of the light rays through the cone-shaped coupler 112. Referring to Figures 1, 5(a), and 5(b), the collimated light rays 114A are generated by the collimator 110 from the light rays generated by the light source 106.

The collimated light rays 114A strike on the outer wall 116 of the coupler 112 such as the cone-shaped coupler 112 and reflect as the reflected light rays 114B towards a periphery of the light guide 108. Herein, the implementation of the coupler 112 reflects the collimated light rays 114A towards a periphery in a uniform manner. Thus, the periphery transmits the received reflected light rays 114B as transmitted light rays 114C out from the light guide 108 to generate the uniform luminance across the periphery.

Figure 6 illustrates a partial perspective view of the light guide 108 depicting the propagation of the light rays through the flower-shaped coupler 112. Referring to Figures 1 and 6, the collimated light rays 114A strike on the plurality of profiles of the flower-shaped coupler 112 and reflect as the reflected light rays 114B towards a periphery of the light guide 108. Herein, the implementation of the flower-shaped coupler 112 reflects the collimated light rays 114A towards a periphery in a uniform manner. Thus, the periphery transmits the received reflected light rays 114B as the transmitted light rays 114C out from the light guide 108 to generate the uniform luminance across the periphery.

Figure 7(a) illustrates a partial perspective view of the light guide 108 depicting the propagation of the light rays through the collimator 110, the coupler 112, and a plurality of air pockets 118 while Figure 7(b) illustrates a top view of the light guide 108 depicting the propagation of the light rays through the collimator 110, the coupler 112, and a plurality of air pockets 118. Referring to Figures 1, 7(a), and 7(b), the collimated light rays 114A strike on the outer wall 116 of the coupler 112 and reflect as the reflected light rays 114B towards the periphery of the light guide 108.

The reflected light rays 114B are received by each of the plurality of air pockets 118. The plurality of air pockets 118 further reflects the received light rays 114 as the second reflected light rays 114D towards the periphery of the light guide 108. The light guide 108 transmits the received second reflected light rays 114D as the transmitted light rays 114C out from the light guide 108. The luminance from the transmitted light rays 114C is uniform across the periphery.

The lighting unit 100 of the present disclosure provides the light guide 108 to receive the light rays from the light source 106. The light guide 108 includes the coupler 112 to receive the collimated light rays 114A from the collimator 110 and to reflect the collimated light rays 114B as reflected light rays towards the periphery. Thus, the implementation of the coupler 112 provides the uniform luminance across the periphery of the light guide 108 which improves the overall illumination. The improved illumination provides more light rays to illuminate the emblem 120. The emblem 120 illuminates effectively to represent the identity of the brand of the vehicle even in the darker conditions.

Further, the plurality of air pockets 118 redirects the reflected light rays 114B towards the dark areas of the emblem 120 to remove hotspots which further improves homogeneity of the light rays to illuminate the emblem 120. The plurality of prismatic structure stripes 124 of the chamfered profile 122 propagates the transmitted light rays to generate better illumination. Moreover, the light guide 108 is cost-effective as the light guide 108 does not required multiple light sources to generate the uniform luminance. The light guide 108 is compact in size, such that the light guide 108 can be easily installed in the vehicle to illuminate the emblem 120.

While specific language has been used to describe the present disclosure, any limitations arising on account thereto, are not intended. As would be apparent to a person in the art, various working modifications may be made to the method to implement the inventive concept as taught herein. The drawings and the foregoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment. , Claims:1. A lighting unit (100) for a vehicle, comprising:
a housing (102) having a hollow compartment (102-1);
a Printed Circuit Board (PCB) (104) disposed in the hollow compartment (102-1) and having a light source (106) mounted thereon to generate light rays (114); and
a light guide (108) having:
a collimator (110) adapted to generate collimated light rays (114A) from the light rays generated by the light source (104); and
a coupler (112) adapted to receive collimated light rays (114A) from the collimator (110) and to reflect the collimated light rays (114A) as reflected light rays (114B) towards a periphery of the light guide (108),
wherein the periphery is adapted to transmit the received reflected light rays (114B) as transmitted light rays (114C) out from the light guide (108) and a luminance from the transmitted light rays (114C) across the periphery is uniform.

2. The lighting unit (100) as claimed in claim 1, wherein the coupler (112) comprises a chamfered periphery defining an outer wall (116) of the coupler (112) and adapted to receive the collimated light rays (114A) via the collimator (110), such that the collimated light rays (114A) are collected and reflected towards the periphery of the light guide (108).

3. The lighting unit (100) as claimed in claims 1 or 2, wherein the coupler (112) is positioned at a predefined gap from the collimator (110), and the collimated light rays (114A) propagate through the predefined gap and strike on the chamfered periphery to generate the uniform luminance.

4. The lighting unit (100) as claimed in claim 1, wherein the light guide (108) comprising a plurality of air pockets (118) formed at a predefined distance from the coupler (112), wherein
each of the plurality of air pockets (118) is adapted to receive the reflected light rays (114B) from the coupler (112) and further reflects the received light rays (114B) as second reflected light rays (114D) towards the periphery of the light guide (108), and
the light guide (108) is adapted to transmit the received second reflected light rays (114D) as the transmitted light rays (114C) out from the light guide (108) and the luminance from the transmitted light rays (114C) across the periphery is uniform.

5. The lighting unit (100) as claimed in claim 1, comprising an emblem (120) disposed in front of the light guide (108) and is adapted to be illuminated by the transmitted light rays (114C).

6. The lighting unit (100) as claimed in claim 2, wherein the chamfered periphery of the coupler (112) defines a conical surface adapted to receive the collimated light rays (114) via the collimator (110).

7. The lighting unit (100) as claimed in claim 2, wherein the chamfered periphery of the coupler (112) defines a plurality of profiles adapted to receive the collimated light rays (114) via the collimator (110).

8. The lighting unit (100) as claimed in claim 1, wherein the light guide (108) comprises a chamfered profile (122) formed on edges of the light guide (108), the chamfered profile (122) having a plurality of prismatic structure stripes (124) to propagate the transmitted reflected light rays (114C).

9. The lighting unit (100) as claimed in claim 1, wherein the light guide (108) comprises an opening adapted to accommodate the collimator (110) and the coupler (112) aligned with the collimator (110).

10. A light guide (108) for a lighting unit (100), comprising:
a collimator (110) adapted to generate collimated light rays (114A) from the light rays generated by a light source (104); and
a coupler (112) adapted to receive collimated light rays (114A) from the collimator (110) and to reflect the collimated light rays (114A) as reflected light rays (114B) towards a periphery of the light guide (108);
a plurality of air pockets (118) formed in the light guide (108) at a predefined distance from the coupler (112), wherein each of the plurality of air pockets (118) is adapted to receive reflected light rays (114B) and further reflects the received light rays (114) as second reflected light rays (114D) towards the periphery of the light guide (108),
wherein the periphery is adapted to transmit the received reflected light rays (114B) and received second reflected light rays (114D) as transmitted light rays (114C) out from the light guide (108) and a luminance from the transmitted light rays (114C) across the periphery is uniform; and
a chamfered profile (122) formed on edges of the light guide (108), the chamfered profile (122) having a plurality of prismatic structure stripes (124) to propagate the transmitted reflected light rays (114C).