Patent Description:
Internal or interior lighting of vehicles, homes, etc. play a major role in the look and feel of the space and also easy access or movement around and within the space. In an automotive environment, i.e., in the interior of a vehicle, it is desired that vehicle controls and accessory controls or knobs are visible in the dark and easily accessible to the driver of the vehicle without causing much distraction.

As an example, ventilation devices/air vents for blowing air towards the passenger compartment should be easy to access/control by the driver even in the dark. Lighting of ventilation devices can be advantageous to make them easier to find such that the driver of the vehicle is not distracted while adjusting the ventilation.

Most conventional ventilation devices/air vents in vehicle interiors are provided with light emitting units illuminated by a light source such as LEDs. Thus, the exterior of the air vents can be illuminated by turning on the light emitting units, improving the discoverability of the ventilation devices/air vents in a dark environment. Similarly, cup holders and other accessory units in a vehicle can also be illuminated by a light source such that the discoverability of such units are also improved.

In most conventional systems, a light guide path for guiding the light from a light source to the light-emitting unit is formed. The light is emitted towards the light emitting units from the light emitting unit, which may be operably manipulated. However, the challenge in implementing the above configurations is associated with limited space in closed areas. As an example, distribution of light from the light source uniformly in all desired areas/corners/positions/directions in the interior is a challenge with the conventional system.

<CIT> discloses a system in accordance with the preamble of claim <NUM>.

Further prior art is known from <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, and <CIT>.

Hence, there is a need for a solution which enables uniform/equal amount of light output to be distributed in all desired areas/corners/positions/directions of an interior space and at the same time managing the interior space effectively.

The object is satisfied by a system in accordance with the features of claim <NUM>. Preferred embodiments of the present invention are described in the dependent claims. In accordance with the present invention, an embodiment provides a rotating illumination system for interior of a vehicle. The rotating illumination system includes one or more first light guides and a second light guide. The one or more first light guides are configured for propagating light, the light being received from one or more illumination sources by a first end of each of the one or more first light guides. The light exits from a second end of each of the one or more first light guides. The second light guide is configured to receive the light homogeneously. The second light guide is movable around its rotational axis to facilitate distribution of the homogeneous light at each position of rotation of the second light guide, wherein the second light guide is circular, wherein the second end of each first light guide is C-shaped, and the second light guide receives the light homogeneously from each C-shaped end of each first light guide in each position of the rotational axis of the second light guide, wherein the system includes two first light guides, wherein each of the two first light guides extends from the first end along a longitudinal axis defining a bar shaped configuration, and the rotational axis passes through the two centers of the C-shaped ends of the two first light guides, wherein the second light guide defines two shapes at two positions along the circumference of the circular second light guide, wherein each of the shapes is parallel and concentric to one of the C-shaped configurations of the two first light guides.

For a more complete understanding of example embodiments of the present technology, reference is now made to the following descriptions taken in connection with the accompanying drawings in which:.

In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent, however, to one skilled in the art that the present invention can be practiced without these specific details. In other instances, systems and methods are shown in block diagram form only in order to avoid obscuring the present invention.

Reference in this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. The appearance of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Similarly, various requirements are described which may be requirements for some embodiments but not for other embodiments.

Moreover, although the following description contains many specifics for the purposes of illustration, anyone skilled in the art will appreciate that many variations and/or alterations to said details are within the scope of the present invention as defined by the appended claims. Similarly, although many of the features of the present invention are described in terms of each other, or in conjunction with each other, one skilled in the art will appreciate that many of these features can be provided independently of other features. Accordingly, this description of the present invention is set forth without any loss of generality to, and without imposing limitations upon the present invention.

Various example embodiments of the present invention provide a system for interior lighting. The system for interior lighting is disposed in the interior of a vehicle, to illuminate areas such as in the air vents, cup holders, or other control knobs or switches present in a vehicle. The system for interior lighting in the present invention is an exemplary system used in air vents.

The system for interior lighting includes one or more illumination sources comprising Light Emitting Diodes (LEDs). The illumination source may even include one or more arrays of LEDs. The system for interior lighting includes one or more first light guides and a second light guide. In accordance with the present invention, the example system for interior lighting in the present invention includes two identical first light guides and one second light guide. The second light guide rotates around its rotational axis. The rotational axis passes through the centers of the first light guides. The rotational axis may be orthogonal to a logitudinal axis of the first light guides.

The first light guides are stationary or fixed. The illumination source may be placed in the stationary part i.e. the first light guides. Alternatively, the illumination source may be placed away and separate from the first light guide but ensuring that not much light escapes the interface between the illumination source and the first light guide. The second light guide and the first light guides are arranged such that an exit surface of the first light guides and an entering surface of the second light guide are parallel and maintains a gap between the second light guide and the first light guides considering the tolerances of the assembly and light guide sizes.

The first light guides facilitate propagation of homogeneous light from the illumination source until a position very close to the entering surface of the second light guide. Homogeneous light is distributed uniformly from the second light guide at all of the rotating positions of the second light guide when the second light guide rotates around the rotational axis.

<FIG> is a representation of a portion of an interior environment of a vehicle where a system <NUM> for interior lighting is deployed/implemented. The system <NUM> is implemented in an interior environment of a vehicle illustrated in <FIG> and is used for description purposes with reference to <FIG>. The system <NUM> is configured as an in-vehicle device. The system <NUM> described with reference to <FIG> finds application in the illumination of air vents of a vehicle, among others. However, the application of system <NUM> is not limited to only illumination of air vents of a vehicle. Other exmplary applications of the system <NUM> could include illumination of control panels and cup holders of a vehicle, rooms of a house and other interior spaces, among others, however only illumination of interior of a vehicle is part of this invention. The system <NUM> could find application in spaces, which may require uniform distribution of light in desired areas, whereby a stationary part serves as an illumination source and a rotating part is configured to distribute light at each position of rotation in every desired area/corner/direction. In the present invention, the system <NUM> is preferably positioned or placed in the air vents of the vehicle, as an example.

As shown in <FIG>, the system <NUM> includes one or more illumination sources <NUM>. The illumination sources <NUM> may include one or more light emitting diodes (LEDs) or any other sources of light. The illumination sources <NUM> may alternatively or additionally include an array on LEDs. The colour of the LEDs may differ based on the application of the system <NUM>. In this example in the present disclosure, the system <NUM> includes one or more white LEDs as the illumination source <NUM>.

The system <NUM> may include one or more first light guides <NUM>. In accordance with the present invention, the system <NUM> includes two identical first light guides <NUM>. The first light guides <NUM> are stationary or fixed and may be connected to some components or parts (e.g. parts already present in the vehicle) of the vehicle. In the preferred embodiment, the illumination source <NUM> may be placed away and separate from the first light guide <NUM> to ensure that not much light escapes the interface between the illumination source <NUM> and the first light guide <NUM>. Alternatively, the illumination source <NUM> may be placed in the stationary part i.e. the first light guides <NUM> of the system <NUM>. The illumination source <NUM> may be placed in the first light guide <NUM> as an interior lighting design, which ensures, that not much light escapes the illumination source <NUM> while entering the first light guides <NUM>. The first light guide <NUM> may be interchangeably referred to as the stationary part throughout the description.

The system <NUM> further includes a second light guide <NUM>. The second light guide <NUM> is rotatable around its rotational axis (see <NUM> in <FIG>). The rotational axis <NUM> passes through the two centers of the two first light guides <NUM>. Light travelling from the illumination source <NUM> is transmitted to the second light guide <NUM> from the first light guides <NUM> at one end (see second end <NUM> in <FIG>) of the first light guide <NUM>. An exit surface of the first light guide <NUM> is present in the second end <NUM> of the first light guide <NUM>. The exit surface of the first light guides <NUM> and the entering surface of the second light guide <NUM> are arranged in a parallel manner such that a gap <NUM> is maintained between the first light guides <NUM> and the second light guide <NUM>. The gap <NUM> is maintained considering the tolerances of the assembly and light guide sizes. The gap <NUM> may be an air gap or vacuum as an example.

In another embodiment, elements which may be used as light transmitting member coincide the rotational axis <NUM>. In other words, a light transmitting member may be positioned in the position of the rotational axis. The light transmitting member ensures the rotation of the second light guide <NUM> and also transmission of light from the first light guides <NUM> to the second light guide <NUM>.

The system <NUM> may further include an emissive member <NUM>. The emissive member <NUM> may include, as an example, self-emissive material, clear material with structure such as white lenses or the like such that light is coupled out in a way as it is desired. The emissive member <NUM> may be an enclosure which houses the second light guide <NUM> which contributes to the appearance of the system <NUM>. Depending on requirements and applications, the system <NUM> may include additional components or circuits, which may be already known to a person of ordinary skill in the art.

The first light guides <NUM> include the light exiting surface at the second end <NUM> of the first light guides <NUM>. The light exiting surface is configured such that homogeneous light leaves the exiting surface of the first light guides <NUM> and enters an entering surface of the second light guide <NUM>. Homogeneous light is distributed uniformly from the second light guide <NUM> at all of the rotating positions of the second light guide <NUM> when the second light guide <NUM> rotates around the rotational axis <NUM>.

Referring to <FIG>, an arrangement of two first light guides 202a, 202b and the second light guide <NUM> are illustrated in two different positions/angles of rotation of the second light guide <NUM>. The second light guide <NUM> rotates to various rotation positions about the rotational axis <NUM>. As an example, and as shown in the <FIG>, the second light guide <NUM> is operably rotatable to an angle of <NUM> degrees on either side (± <NUM>°) of the rotational axis <NUM>. Each position/angle of rotation of the rotating part <NUM> is defined at various angles of rotation of the second light guide <NUM>. Example positions/angles of rotation may include e.g., +<NUM>°, +<NUM>°, +<NUM>°, +<NUM>°, -<NUM>°, -<NUM>°, -<NUM>° and so on). As the second light guide <NUM> rotates around the rotational axis <NUM>, at each position/angle of rotation (e.g. +<NUM>°, +<NUM>°, +<NUM>°, +<NUM>°, -<NUM>°, -<NUM>°, -<NUM>° and so on), the light distribution is uniform and equal in amount. It shall be noted that in this scenario, the amount of rotation is limited by the angle at which the second light guide <NUM> meets the first light guides <NUM>. The shapes of the light guides could be also adapted to cover a bigger angle for various other applications.

The first light guides 202a and 202b facilitate propagation of homogeneous light from the illumination source <NUM>. For example, the first light guide 202a facilitates propagation of homogeneous light from the illumination source <NUM> from the first end <NUM> of the first light guide 202a to the second end <NUM> of the first light guide 202a. The illumination source <NUM> may be configured/placed/implemented at the first end <NUM> of the first light guide 202a. Similarly, the first light guide 202b facilitates propagation of homogeneous light from the illumination source <NUM> from a first end of the first light guide 202b to a second end of the first light guide 202b. The illumination source <NUM> may be placed at the first end of the first light guide 202b. The exiting surface of the first light guides <NUM> and the entering surface of the second light guide <NUM> are arranged in a parallel manner such that the gap <NUM> is maintained between the first light guides <NUM> and the second light guide <NUM>. Light from the first light guides 202a and 202b is coupled to the second light guide <NUM> axially or laterally via the gap <NUM>. The second end <NUM> of the first light guide 202a ensures that homogeneous light is received by the second light guide <NUM> from the second end <NUM> (<FIG>). Similarly, the second end of the first light guide 202b ensures that homogeneous light is received by the second light guide <NUM> from the second end of the first light guide 202b. The second light guide <NUM> then ensures uniform distribution of the light in desired areas when the second light guide <NUM> rotates around the rotational axis <NUM>. The rotational axis <NUM> is positioned orthogonal to a longitudinal axis of the first light guides 202a and 202b as seen in the figures.

In another embodiment, the system <NUM> includes one or more ribs that facilitate the engagement of first light guides <NUM> with the second light guide <NUM> to ensure distribution of the homogeneous light in target areas as the second light guide rotates around its rotational axis. For example, the coupling the first light guide and the second light guide using absorptive ribs may ensure distribution of homogeneous light only in an upper area of the second light guide <NUM>. The ribs may include absorptive ribs as an example.

<FIG> represents an exemplary first light guide <NUM>, in accordance with an embodiment of the present invention. The first light guide illustrated in <FIG> may be the example first light guide 202a or 202b. For the ease of the description, let's assume the first light guide 202a. The first light guide 202a includes the first end <NUM> and the second end <NUM>. The second end of the first light guide 202a defines a "C" shaped configuration. The first light guide 202a extends from the first end <NUM> along a longitudinal axis defining a bar shaped configuration. The bar shaped first light guide 202a defines the "C" shaped configuration at the second end <NUM> which is the light exiting surface of the first light guide 202a. The first end <NUM> may house the illumination source <NUM> of the system <NUM>. A shape defined in the second light guide <NUM> is engaged with the first light guide 202a by maintaining the gap <NUM> between the two light guides. The shape or profile of the first light guide <NUM> is not limited to the example shapes illustrated in <FIG>. In some embodiments, the shape of the first light guide <NUM> may be trapezoidal (not shown in FIGs). The first light guide may be composed of one or more of Poly methyl methacrylate (PMMA), Polycarbonate (PC) and flexible silicon, among others. The first light guide <NUM> may additionally or alternatively be configured with metallized surface or mirrors to achieve better light transmission and to facilitate better light propagation of homogeneous light to the second light guide.

<FIG> is an illustration of an exemplary second light guide <NUM> in accordance with an embodiment of the present invention. The second light guide <NUM> is configured in a circular configuration. The second light guide <NUM> defines two or more shapes (502a and 502b) at two or more positions along the circumference of the circular second light guide <NUM>. The shapes 502a and 502b are configured/defined such that they complement the C-shaped configuration of the first light guides <NUM>. In this example, because of the shapes of the first light guides <NUM> and the second light guide <NUM> the exiting surface of the first light guides <NUM> and the entering surface of the second light guide <NUM> are arranged in a concentric fashion such that the gap <NUM> is maintained between the first light guides <NUM> and the second light guide <NUM>. When light is coupled from the first light guides <NUM> to the second light guide <NUM>, light is distributed uniformly in all desired areas of a space at all positions of rotation of the second light guide <NUM>. The second light guide is composed of one or more of Poly methyl methacrylate (PMMA), Polycarbonate (PC) and flexible silicon, among others.

The embodiments disclosed herein provide numerous advantages. The system disclosed herein enables the system for interior lighting by implementing a stationary unit and a rotational unit to distribute light uniformly around the interior of a vehicle. Lighting of air vents and control panels of a vehicle is of critical importance from the perspective of Automated-Driver-Assistance-Systems (ADAS), which helps to avoid accidents by ensuring lighting systems mitigates driver distraction and ensure safe driving.

Claim 1:
A rotating illumination system for interior of a vehicle, the rotating illumination system comprising:
one or more first light guides (<NUM>) for propagating light, the light being received from one or more illumination sources by a first end (<NUM>) of each of the one or more first light guides (<NUM>), wherein the light exits from a second end (<NUM>) of each of the one or more first light guides (<NUM>); and
a second light guide (<NUM>) configured to receive the light from one or more first light guides (<NUM>) homogeneously, the second light guide (<NUM>) movable around its rotational axis (<NUM>) to facilitate distribution of the homogeneous light at each position of rotation of the second light guide (<NUM>),
wherein the second light guide (<NUM>) is circular, and
wherein the second end (<NUM>) of each first light guide (<NUM>) is C-shaped, and the second light guide (<NUM>) receives the light homogeneously from each C-shaped end of each first light guide (<NUM>) in each rotation position of the second light guide (<NUM>) about the rotational axis (<NUM>),
characterized in that
the system includes two first light guides (202a, 202b), wherein each of the two first light guides (202a, 202b) extends from the first end (<NUM>) along a longitudinal axis defining a bar shaped configuration, and the rotational axis (<NUM>) passes through the two centers of the C-shaped ends of the two first light guides (202a, 202b), wherein the second light guide (<NUM>) defines two shapes (502a, 502b) at two positions along the circumference of the circular second light guide (<NUM>) which are configured such that they complement the C-shaped configuration of the first light guides (<NUM>),
wherein each of the shapes (502a, 502b) is parallel and concentric to one of the C-shaped configurations of the two first light guides (202a, 202b).