Vehicle interior lighting apparatus

Abstract

A vehicle interior lighting apparatus is disclosed. It includes an elongate light guide having at least one end-side light input coupling surface, a longitudinal light deflection surface and a longitudinal light output coupling surface opposite the light deflection surface, and at least one light source, the light of which is able to be coupled into the light guide at the at least one light input coupling surface and able to be coupled out of the light guide at the light output coupling surface by way of a light deflection at the light deflection surface. At least one light deflection prism is disposed optically downstream of the light output coupling surface and there is at least one jump between two refractive indices in a light path between the light guide and the at least one light deflection prism and the at least one light deflection prism is disposed between two adjacent light deflection regions when viewed perpendicular to the light output coupling surface. A vehicle has at least one vehicle interior lighting apparatus. An application for the disclosed apparatus includes door lighting.

Claims

1. A vehicle interior lighting apparatus, comprising: an elongated light guide comprising at least one front side light input coupling surface, a longitudinal light deflection surface and a longitudinal side opposite the light deflection surface opposite a light output coupling surface wherein at the light deflection surface several light deflection regions are arranged spaced apart from one another in a longitudinal direction of the light guide, and light from the at least one light source enters the light guide through the at least one light input coupling surface and is decoupled from the light guide by means of light deflection at the light deflection surface and exits the light output coupling surface, wherein at least one light deflection prism of the light output coupling surface is connected downstream, wherein at least one jump between two refractive indices occurs in a light path between the light guide, wherein the at least one light deflection prism, is arranged between two adjacent light deflection regions when viewed perpendicular to the light output coupling surface, wherein the at least one light deflection prism when viewed from a perspective perpendicular to the light output coupling surface is arranged between the light deflection regions, and wherein downstream indicates the direction of the light flow.

2. The vehicle interior lighting apparatus according to claim 1, further comprising a plurality of light deflection prisms arranged separately from each other on the light output coupling surface.

3. The vehicle interior lighting apparatus according to claim 1, wherein the light guide comprises a different refractive index than the at least one light deflection prism.

4. The vehicle interior lighting apparatus according to claim 1, wherein at least one light deflection prism is a component separate from the light guide, comprises different refractive index than the light guide, and rests directly on the light guide.

5. The vehicle interior lighting apparatus according to claim 1, wherein at least one light deflection prism and the light guide form a component arranged as one element and further comprising the at least one light deflection prism that has a different refractive index than the light guide.

6. The vehicle interior lighting apparatus according to claim 1, wherein at least one light deflection prism is spaced from the light guide by a gap.

7. The vehicle interior lighting apparatus according to claim 6, wherein the gap is an air gap.

8. The vehicle interior lighting apparatus according to claim 6, wherein the gap is filled with a solid material having refractive index that is different from a refractive index of at least the at least one light deflection prism differentiated and wherein solid material refers to the aggregate state of the material.

9. The vehicle interior lighting apparatus according to claim 1, further comprising a plurality of light deflection prisms spaced apart from one another in the longitudinal direction of the light guide, the light deflection prisms each being arranged between two adjacent light deflection regions when viewed perpendicular to the light output coupling surface.

10. The vehicle interior lighting apparatus according to claim 1, wherein at least one light deflection prism protrudes laterally at least on one side beyond the light output coupling surface of the light guide.

11. A vehicle comprising: at least one vehicle interior lighting apparatus comprising an elongated light guide comprising at least one front side light input coupling surface, a longitudinal light deflection surface and a longitudinal side opposite the light deflection surface opposite a light output coupling surface wherein at the light deflection surface several light deflection regions are arranged spaced apart from one another in a longitudinal direction of the light guide, and light from the at least one light source enters the light guide through the at least one light input coupling surface and is decoupled from the light guide by means of light deflection at the light deflection surface and exits the light output coupling surface, wherein at least one light deflection prism of the light output coupling surface is connected downstream, wherein at least one jump between two refractive indices occurs in a light path between the light guide, wherein the at least one light deflection prism is arranged between two adjacent light deflection regions when viewed perpendicular to the light output coupling surface, wherein the at least one light deflection prism from a perspective perpendicular to the light output coupling surface is arranged between the light deflection regions, and wherein downstream indicates the direction of the light flow.

12. The vehicle according to claim 11, wherein at least one vehicle interior lighting apparatus is set up for illuminating a door and the at least one light deflection prism is arranged in relation to the light guide such that it scatters light directed from the light output coupling surface in the direction next to at least one of a useful light area and next to a door onto the useful light area.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

(1) Further advantages features and details of the various embodiments of this disclosure will become apparent from the ensuing description of a preferred exemplary embodiment and with the aid of the drawings. The features and combinations of features recited below in the description, as well as the features and feature combination shown after that in the drawing description or in the drawings alone, may be used not only in the particular combination recited, but also in other combinations on their own, with departing from the scope of the disclosure

(2) The following is an advantageous embodiment of the present disclosure which is schematically explained in more detail with reference to the accompanying figures. wherein:

(3) FIG. 1 depicts, in an oblique view, a vehicle interior lighting apparatus according to the present disclosure;

(4) FIG. 2 depicts, as a sectional view, a simplified sketch of a section of the vehicle interior lighting apparatus from FIG. 1;

(5) FIG. 3 depicts a section of a vehicle with the vehicle interior lighting apparatus from FIG. 1 as a section in front view; and

(6) FIG. 4 depicts the gap filled with solid material.

DETAILED DESCRIPTION OF THE INVENTION

(7) As used throughout the present disclosure, unless specifically stated otherwise, the term “or” encompasses all possible combinations, except where infeasible. For example, the expression “A or B” shall mean A alone, B alone, or A and B together. If it is stated that a component includes “A, B, or C”, then, unless specifically stated otherwise or infeasible, the component may include A, or B, or C, or A and B, or A and C, or B and C, or A and B and C. Expressions such as “at least one of” do not necessarily modify an entirety of the following list and do not necessarily modify each member of the list, such that “at least one of “A, B, and C” should be understood as including only one of A, only one of B, only one of C, or any combination of A, B, and C.

(8) FIG. 1 depicts an oblique view of a vehicle interior lighting apparatus 1, which has an elongated light guide 2 made of a transparent material with a refractive index n1, for example made of plastic such as PC or PMMA.

(9) The light guide 2 is designed as a profiled body extending rectilinearly along its longitudinal direction x with length L and with a rectangular, constant cross-sectional shape. In the height direction y perpendicular to the longitudinal direction x, it has a height H, and in the width direction z perpendicular to the longitudinal direction x and to the height direction y, it has a width B, where L>>H and L>>B, in particular L−10H and L−10B. The light guide 2 can thus also be referred to as a rod light guide. Furthermore, purely by way of example, H>B applies, in particular H−2B, especially H−5B. The light guide 2 is therefore noticeably higher than it is wide.

(10) The vehicle interior lighting apparatus 1 further comprises at least one light source 3, for example in the form of at least one LED, the light of which can be coupled into one of the two end faces. This end face thus provides or represents a front-side light input coupling surface 4. The parallel narrow sides of the light guide 2 with the surfaces L B provide or represent a longitudinal light deflection surface 5 in relation to a longitudinal light output coupling surface 6 and are thus opposite each other. Light emitted by the light source 3 through the light input coupling surface 4 into the light guide 2 is guided in this generally known manner, for example by total reflection.

(11) A plurality of light deflection regions arranged in series along the longitudinal direction x and spaced apart from one another are introduced on the light deflection surface 5 in the form of notches 7. The notches 7 have here, for example, a different size and shape depending on the light input coupling surface 4 in order to achieve a uniform decoupling of useful light over the longitudinal direction x. A shape of the notches can also vary. All notches 7 are here exemplary formed consistently in width direction z.

(12) If light guided in the light guide 2 hits one of the notches 7, it is redirected by the latter to the light output coupling surface 6 in such a way that the angle of incidence there allows an extraction from the light output coupling surface 6.

(13) Several light deflection prisms 8 arranged in series in the longitudinal direction x are arranged opposite the light output coupling surface 6 optically behind the light output coupling surface 6 and at a distance therefrom. The light deflection prisms 8 are arranged separately from one another on the light output coupling surface and are not connected to one another with respect to the light output coupling surface 6, for example, via a common carrier film or similar. However, they can be connected to each other outside a light path, for example in the form of a single light path. component produced in one piece. The light deflection prisms 8 are designed as profile bodies extending in a straight

(14) line in the direction of width z, each having in particular a constant size and/or shape of the cross-section but are generally not limited to this. The cross-section is an example of a triangular cross-section.

(15) The light deflection prisms 8 have in particular been produced separately from the light guide 2. Compared to the light guide 2, they may consist of a material having a refractive index n2 which is the same or different from the refractive index n1 of the light guide n2, for example made of plastic or glass. The light deflecting prisms 8 here exemplarily have a different size, shape and/or orientation depending on the light input coupling surface 4.

(16) FIG. 2 depicts a simplified sketch of a section of the vehicle interior lightning apparatus 1 in the region of a longitudinal section of the light guide 2 having two equal notches 7 and two equal light deflection prisms 8. The light deflection prisms 8 have a length s, a height t and a width u.

(17) In particular, the light deflection prisms 8 protrude laterally on both sides (that is, in the direction of width z) beyond the light output coupling surface 6 of the light guide 2, in relation to the latter. So u>B applies. This advantageously results in particularly reliable glare control.

(18) The notches 7 are spaced apart from each other in the longitudinal extension or longitudinal direction x with an edge-to-edge distance d. When viewed, the light deflection prisms 8 are arranged perpendicular to the light output coupling surface 6 or in relation to their position along the longitudinal direction x between the notches 7.

(19) The light deflection prisms 8 are also arranged at a distance from the light guide 2 by a respective air gap 9. As a result, at least one jump between two refractive indices occurs in a respective light path between the light guide 2 and the light deflection prisms 8, namely here at the light output coupling surface 6 of the light guide 2 to the air gap 9 and at the light entry surface 10 of the respective light deflection prism 10. It is assumed that the refractive indices n1 and n2 differ from the refractive index n0 of air, in particular are greater.

(20) The light L deflected by the notches 7 is predominantly decoupled from the light output coupling surface 6 in an area opposite the notches 7, namely as useful light LN, which passes between the light deflection prisms 8 without being influenced by them. This

(21) useful light range NB corresponds here to a solid angle range of approximately ±50° to the perpendicular of the light output coupling surface 6.

(22) However, starting from the notches 7, also (“scattered light”-) component LS of the light L also strike the light output coupling surface 6 at such a flat angle that they subsequently strike the light deflection prisms 8 and are at least partially deflected by them into the useful light region NB. This is particularly advantageous since it not only avoids disturbing, in particular potentially blinding, scattered light LS, but is also used to amplify the useful light LN.

(23) The light deflection prisms 8 are advantageously shaped and arranged in such a way that at least one of the following conditions is fulfilled for the particularly effective light deflection and for achieving a high light yield: The light entry surface 10 is parallel or tangential to the opposite region of the light output coupling surface 6; The length s of a light deflection prism 8 is less than the distance d of two adjacent notches 7, in particular two diagonally opposite adjacent notches 7; Corners—and—of the light entry surface 10 to the other surfaces of light deflection prisms 8 are each smaller than 90°; The height of the light deflection prisms 8 is between 1 mm and 10 mm.

(24) At least one such condition may also be considered generally advantageous. The angles—and—may have an equal or different size.

(25) FIG. 3 depicts a sectional view from the front of a vehicle F with at least one vehicle interior lighting apparatus 1 for illuminating a door T of the vehicle F. The vehicle interior lighting apparatus 1 is accommodated in a housing in the region of a headliner D. The associated or useful light region NB is directed to an inner side of the door T below a door pane S as the illumination area.

(26) FIG. 4 depicts antoher view of the present invention as depicted for example in FIG. 2. In FIG. 4 the gap 9 is depicted including a solid material used in the gap, the solid material being depicted by way of a greyed-out portion of the gap 9.

(27) The light deflection prisms 8 are arranged with respect to the light guide 2 in such a way that they deflect scattered light LS from the light output coupling surface 6 in the direction next to the door T—for example in the direction of a C-pillar C, which is located here behind a door pane S—onto the door T. Thus, the advantage is achieved that a vehicle occupant is not blinded by the vehicle interior lighting apparatus 1 when he leans his head against the C-pillar C for relaxation. It has been shown experimentally that otherwise interfering scattered light LS incident on the C-pillar C can be reduced by 90% to 95% in relation to its intensity by providing light deflection prisms 8.

(28) In principle, one or more vehicle interior lighting apparatus 1 can be used to illuminate an area of a vehicle interior or interior.

(29) The figures are merely schematic representations and serve only to explain the present disclosure. Identical elements or similar are consistently provided with the same reference signs.

(30) Although the vehicle interior lighting apparatus 1 has been described in FIG. 1 and FIG. 2 on the basis of light deflection prisms 8 with a triangular cross-section, the cross-sectional shape may generally differ from this, for example, it may be trapezoidal. The above advantageous conditions for light deflection prisms 8 with a triangular cross-section can then also apply, for example, to light deflection prisms with a trapezoidal cross-section.

(31) The use of the vehicle interior lighting apparatus is not limited to the examined door lighting, but can be used for all possible lighting tasks, in particular for indirect lighting tasks, in the vehicle interior.

(32) In general, the radiation direction and the opening angle of the useful light range can be adapted to a desired application purpose by suitable selection of the number, arrangement, shape and size of the light deflection prisms, for different application purposes if necessary, possible using the same combination of light source and light guide, which allows a particularly flexible and cost-effective design of the vehicle interior lighting apparatus.

(33) Having described some aspects of the present disclosure in detail, it will be apparent that further modifications and variations are possible without departing from the scope of the disclosure. All matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.