Dual light guide by optical coupling at the end
The dual light guide system with optical coupling addresses the limitations of existing vehicle lighting systems by enabling flexible window illumination and reducing costs through efficient photon redirection and single-source illumination.
Patent Information
- Application Number
- FR2022008481
- Authority / Receiving Office
- FR · FR
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2022-08-24
- Publication Date
- 2025-11-28
- Estimated Expiration
- 2042-08-24
AI Technical Summary
Existing lighting systems for vehicles face limitations in creating style masks with maximum freedom and efficiency, particularly when illuminating windows of varying dimensions, often requiring multiple light guides or large-diameter guides, which are costly and limit design possibilities.
A dual light guide system is implemented with optical coupling at the ends to redirect photons between light guides, allowing for variable angles and reducing the need for multiple photon sources, while using a single photon source and minimizing manufacturing costs through a single injection molding process.
The system enables a wider variety of mask styles, reduces manufacturing costs, and achieves homogeneous illumination with greater design freedom for windows of varying dimensions.
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Abstract
Description
Title of the invention: Dual light guide by end-to-end optical coupling. Technical field
[0001] The present invention relates to the projectors or lights which equip vehicles, for example of automobile type, to ensure a lighting and / or visual signaling function. Technological background
[0002] Vehicles are equipped with lighting systems dedicated to the visual signaling of the vehicle such as, for example, front or rear lights or daytime running lights, also called daytime running lamps or daytime running light.
[0003] In this type of lighting system, it is common to use optical systems of the "light guide" type.
[0004] Fig. 1 schematically illustrates a light guide.
[0005] The light guide is usually in the form of a cylindrical tube A comprising two ends. At one of these ends, a photon source B is positioned. This photon source B is intended to produce photons that propagate along the cylindrical tube A to light-reflecting means C positioned on one side of the cylindrical tube A, either along its entire length or only partially. These light-reflecting means C are very often prisms whose function is to modify the trajectories of the photos, which are then redirected in a desired direction, typically transverse to the axis of the light guide A.
[0006] It is known to use style masks that define the visual appearance of a luminous object. Usually, a style mask is opaque except for certain parts of it, called windows, through which beams of light emerge from photons propagating along a cylindrical light guide positioned behind the style mask. If the desired style mask is to obtain windows with one dimension that is, for example, twice the diameter of the cylindrical light guide, one could consider using a light guide with a larger diameter. However, the dimensions of the windows may not be constant, and it is then financially costly to use large-diameter light guides to illuminate only a few windows with one dimension equal to the diameter of that light guide.
[0007] Another alternative is to use a first light guide of small diameter to illuminate some windows of the style mask and to superimpose a second (or more) light guide of small diameter to illuminate windows whose dimension would be larger.
[0008] The superposition of two, or even more, light guides limits the possibilities of the style mask, whereas it is desirable to give maximum freedom to create these style masks.
[0009] The problem is to define a lighting system that allows maximum freedom for the creation of style masks. Summary of the present invention
[0010] One of the objects of the present invention is to solve at least one of the problems or deficiencies of the technological background described above.
[0011] Another object of the present invention is to obtain a lighting system for equipping a vehicle which produces homogeneous lighting while using a limited number of light guides.
[0012] Another object of the present invention is to obtain a lighting system which allows great freedom in the design of windows of a style mask.
[0013] The present invention consists of creating a coupling between pairs of light guides at one of their ends by means of an optical coupling means intended to redirect the photons arriving at the end of a first light guide towards the end of a second light guide so as to be able to illuminate windows of different dimensions of a style mask.
[0014] The present invention is particularly advantageous because it allows for a much wider variety of mask styles than those currently available. Indeed, thanks to the optical coupling method, two light guides can be coupled at variable angles, which is not possible using a single light guide, due to limitations in its radius of curvature, or by superimposing light guides.
[0015] The present invention is also advantageous because it uses only one photon source and not one photon source per light guide.
[0016] In addition, the cost of manufacturing by plastic injection is reduced because only one injection is needed to produce the different coupled guides.
[0017] According to a first aspect, the present invention relates to a lighting system intended to equip a vehicle, comprising - a photon source; - a first cylindrical light guide comprising a first end intended to be illuminated by the photon source; - a second cylindrical light guide comprising a first end coupled to a second end of the first light guide by an optical coupling means intended to redirect photons arriving at the second end of the first cylindrical light guide towards the first end of the second cylindrical light guide; - an opaque mask including windows through which parts of the first and / or second cylindrical light guide are visible; - a light reflection means being positioned at each part of the first and / or second cylindrical light guide corresponding to a window of the style mask so that photons propagating along the first and / or second cylindrical light guides are redirected to said window.
[0018] According to one variant, the optical coupling means and the first end of the second cylindrical light guide are masked.
[0019] According to one variant, at least one of said windows is equipped with optics or glass.
[0020] According to one variant, a second end of the second cylindrical light guide is obstructed.
[0021] According to one embodiment, the first and second cylindrical light guides are longitudinally superimposed on each other at least on one of their parts; the optical coupling means is adapted to redirect the photons at an angle of 180 degrees; at least one of said windows, called the first window, has one of its dimensions which is less than a sum of the diameters of the first and second cylindrical light guides; and at least one of said windows, called the second window, has one of its dimensions which is at least equal to the sum of the diameters of the first and second cylindrical light guides.
[0022] According to a variant of this embodiment, the optical coupling means comprises a prism comprising two light-reflecting faces inclined at 45 degrees.
[0023] According to a variant of this embodiment, the second end of the second cylindrical light guide is mechanically connected to the first light guide.
[0024] According to one embodiment, the optical coupling means comprises a light-reflecting face inclined at an angle less than or equal to 90 degrees.
[0025] According to one variant, the lighting system further comprises a third light guide including a first end coupled to the second end of the second light guide by another optical coupling means.
[0026] According to a second aspect, the present invention relates to a vehicle, for example of the automobile type or of the land motor vehicle type, comprising at least one lighting system according to the first aspect of the present invention. Brief description of the figures
[0027] Other features and advantages of the present invention will become apparent from the description of the particular and non-limiting embodiments of the present invention below, with reference to the attached Figures 1 to 9, in which:
[0028] [Fig-1] schematically illustrates a light guide.
[0029] [Fig.2] schematically illustrates a lighting system according to an example of realization of the present invention;
[0030] [Fig.3] schematically illustrates a coupling of two light guides according to an example of an embodiment of the present invention;
[0031] [Fig.4] schematically illustrates a means of light reflection along a light guide according to an example of an embodiment of the present invention;
[0032] [Fig.5] schematically illustrates a means of optical coupling between two light guides according to an example of an embodiment of the present invention;
[0033] [Fig.6] schematically illustrates optical coupling constraints between two light guides according to an example of an embodiment of the present invention;
[0034] [Fig.7] schematically illustrates, according to a variant of coupling of two light guides, an example of an embodiment of the present invention;
[0035] [Fig.8] schematically illustrates, according to a variant of coupling of two light guides, an example of an embodiment of the present invention;
[0036] [Fig.9] schematically illustrates a variant of coupling two light guides, an example of an embodiment of the present invention. Description of examples of achievements
[0037] A lighting system intended to equip a vehicle will now be described in the following with joint reference to Figures 2-9. Unless otherwise indicated, elements common or similar to several figures bear the same reference signs and have identical or similar characteristics, so that these common elements are generally not described again for the sake of simplicity.
[0038] Figures 2-9 schematically illustrate a lighting system according to a particular, non-limiting embodiment and various variant embodiments. It is hereafter considered, by way of non-limiting example, that the lighting system is intended to equip a motor vehicle, but the present invention is not limited to this application. The lighting system can in fact equip any vehicle, whether a motor vehicle or a motorized land vehicle (bus, coach, truck, etc.), which must provide at least a photometric function for lighting and / or signaling.
[0039] Furthermore, it is subsequently considered that the lighting system comprises two or even three light guides, but the present invention is not limited to these numbers of light guides. The present invention extends to any lighting system that would include more than three light guides coupled in pairs as well as coupling means which redirect photons at any angle.
[0040] Figures 2-9 illustrate different aspects of the lighting system, different examples of embodiments implementing some of these aspects being described later with reference to the figures.
[0041] Fig. 2 schematically illustrates a lighting system 1 according to an example of an embodiment of the present invention.
[0042] System 1 includes a style 2 mask. The style 2 mask is opaque and made, for example, of plastic material.
[0043] The mask 2 is opaque except in certain parts 16 and 17 of it, called windows, through which portions of light guides are visible, i.e., beams of light emerge from these windows. These beams of light originate from photons propagating along these light guides positioned behind the style mask 2.
[0044] According to an exemplary embodiment, at least one of the windows of the style mask 2 is provided with a translucent material, preferably having optics / beading for example in opaline material, in order to blur the or each cylindrical light guide visible through said at least one window.
[0045] The lighting system 1 comprises a photon source 11, a first cylindrical light guide 12, a second cylindrical light guide 13 and a first optical coupling means 14.
[0046] The first cylindrical light guide 12 includes a first end intended to be illuminated by the photon source 11. The second cylindrical light guide 13 includes a first end coupled to a second end of the first cylindrical light guide 12 by an optical coupling means 14 intended to redirect the photons arriving at the second end of the first cylindrical light guide 12 towards the first end of the second cylindrical light guide 13.
[0047] According to one variant, the optical coupling means 14 and the first end of the second cylindrical light guide 13 are masked to obtain homogeneous illumination.
[0048] According to one variant, the second end of the second cylindrical light guide 13 is obstructed.
[0049] The lighting system 1 also includes a light-reflecting means 18 ([Fig.4]) positioned at each part of the first 12 and / or second 13 cylindrical light guides corresponding to a window of the style mask 2 so that photons propagating along the first or second cylindrical light guides are redirected to said window in a desired direction.
[0050] For example, the optical light-reflecting means 18 redirects transversely the photons propagating longitudinally along a light guide.
[0051] Figure 3 schematically illustrates a coupling of two light guides according to an example of an embodiment of the present invention.
[0052] The first 12 and second 13 cylindrical light guides are longitudinally superimposed on each other at least on one of their parts. The optical coupling means 14 is adapted to redirect the photons arriving at the end of the first cylindrical light guide 12 at an angle of 180 degrees so that they propagate along the second cylindrical light guide 13. At least one of the windows of the style mask 2, called the first window 16, has one of its dimensions that is less than the sum of the diameters of the first 12 and second 13 cylindrical light guides, and at least one of said windows, called the second window 17, has one of its dimensions that is at least equal to the sum of the diameters of the first 12 and second 13 cylindrical light guides.
[0053] According to the example of [Fig.3], the style mask 2 comprises three first windows 16 making visible three parts of the first cylindrical light guide 12 making visible parts of the first light guide 12, and a second window 17 making visible a part of the first cylindrical light guide 12 and a part of the second cylindrical light guide 13.
[0054] According to a variant of the embodiment example of [Fig.3], illustrated in [Fig.5], the optical coupling means 14 comprises a prism comprising two light-reflecting faces inclined at 45 degrees.
[0055] Photons arriving at the second end of the first cylindrical light guide 12 are redirected to the first end of the second cylindrical light guide 13, the base of which is located on the protrusion of the prime. The first 12 and second 13 light guides include a light-reflecting means 18 corresponding to each window 16 and 17 of the style mask 12. Due to the opposite direction of the photons between the two visible parts of the light guides, the light-reflecting means 18 positioned along the first light guide 12 and those positioned along the second light guide 13 have opposite angles so that the resulting photon beam follows the same desired direction.
[0056] Fig. 6 schematically illustrates coupling constraints between the two cylindrical light guides 12 and 13 according to the optical coupling of Fig. 3.
[0057] To have good optical efficiency (physical limit of the principle of total reflection in a translucent medium), one of these constraints is that the curvature of the first cylindrical light guide 12 has a positive angle (in the counter-clockwise direction) with respect to the desired lighting direction D.
[0058] Another of these constraints is that the angle formed by the longitudinal axes of the first and second cylindrical light guides be positive (in the counterclockwise direction) with respect to the desired lighting direction D, in order to have good optical efficiency.
[0059] Fig. 7 schematically illustrates, according to a coupling variant, the two cylindrical light guides 12 and 13 coupled according to the optical coupling of Fig. 3.
[0060] According to this variant, the second end of the second cylindrical light guide 13 is mechanically connected to the first light guide 12, for example by means of a rib 21.
[0061] According to one variant, illustrated in [Fig.8], the optical coupling means 14 comprises a light-reflecting face inclined at an angle less than or equal to 90 degrees.
[0062] Fig. 9 schematically illustrates a variant of coupling three light guides, an example of an embodiment of the present invention.
[0063] According to this example, the second end of the first cylindrical light guide 12 is coupled to the first end of the second cylindrical light guide 13 by means of a coupling device 14 designed to redirect the photons at an angle of less than 90 degrees. The second end of the second cylindrical light guide 13 is coupled to a first end of a third light guide 19 by means of a second optical coupling device 20 designed to redirect the photons at an angle of 90 degrees.
[0064] The principle of optical coupling between two light guides by means of optical coupling can be extended to more than three light guides.
[0065] According to one variant, each photon source may, for example, include at least one light-emitting diode or at least one laser diode or at least one light bulb.
[0066] According to one variant, said at least one photon source is carried by an electronic card.
[0067] The configuration of the photon source(s) in terms of number, positioning, arrangement, type, etc., can be adapted by a person skilled in the art as appropriate. The electronic board includes electronic means configured to control the operation of each photon source. This board can, for example, be a printed circuit board (PCB). The electronic board is mounted on a plane, meaning that all the photon sources are mounted on this plane.
[0068] A person skilled in the art will understand that the embodiments and variants described above are only non-limiting examples of implementation of the invention. In particular, a person skilled in the art may consider any adaptation or combination of the examples of implementation and variants described above, in order to meet a very specific need.
[0069] The present invention is therefore not limited to the embodiments described above but extends in particular to a lighting system which would include secondary features without going outside the scope of the present invention.
[0070] The present invention also relates to a vehicle, for example a motor vehicle or more generally a land motor vehicle, comprising at least one lighting system as described above.
Claims
Demands
1. Lighting system (1) for equipping a vehicle, comprising: - a photon source (11); - a first cylindrical light guide (12) comprising a first end intended to be illuminated by the photon source (11); - a second cylindrical light guide (13) comprising a first end coupled to a second end of the first light guide (12) by an optical coupling means (14) intended to redirect the photons arriving at the second end of the first cylindrical light guide (12) to the first end of the second cylindrical light guide (13); - an opaque mask (2) comprising windows (16, 17) through which parts of the first and / or the second cylindrical light guide are visible;- a light-reflecting means (18) being positioned at each part of the first (12) and / or the second (13) cylindrical light guides corresponding to a window of the style mask (2) so that photons propagating along the first (12) and / or the second (13) cylindrical light guides are redirected towards said window in a desired direction, characterized in that the first (12) and second (13) cylindrical light guides are longitudinally superimposed on each other at least on one of their parts; - the optical coupling means (14) is adapted to redirect the photons at an angle of 180 degrees; - at least one of said windows, called the first window (16), has one of its dimensions which is less than a sum of the diameters of the first (12) and second (13) cylindrical light guides;and - at least one of said windows, called second window (17), has one of its dimensions which is at least equal to the sum of the diameters of the first (12) and second (13) cylindrical light guides.;
2. Lighting system (1) according to claim 1, wherein the optical coupling means (14) and the first end of the second cylindrical light guide (13) are masked.
3. Lighting system (1) according to claim 1 or 2, wherein at least one of said windows is provided with optics or lenses.
4. Lighting system (1) according to any one of claims 1 to 3, wherein a second end of the second cylindrical light guide (13) is obstructed.
5. Lighting system (1) according to any one of the preceding claims, wherein the optical coupling means (14) comprises a prism comprising two light-reflecting faces inclined at 45 degrees.
6. Lighting system (1) according to any one of the preceding claims, wherein the second end of the second cylindrical light guide (13) is mechanically connected to the first light guide (12).
7. Lighting system according to any one of claims 1 to 3 or 5 to 7, further comprising a third light guide (19) comprising a first end coupled to the second end of the second light guide by another optical coupling means (20).
8. Vehicle comprising at least one lighting system (1) according to any one of the preceding claims.