The present invention relates to the field of illumination and signalling, especially for automotive vehicles. It relates more particularly to an illumination or signalling device having a plurality of LEDS as light sources, and wherein the spatial scattering of the light emitted is enhanced, whereas the scattered light further provides a three-dimensional effect at the output thereof from the device. Such a device may be especially used as a signal light, indicator, both at the rear and the front of the vehicle, or as a position light or stop light.
The current regulations require, according to the types of vehicles, various illumination or signal lamps. However, besides the volume of the set of lights, the performances and uniformity of illumination of the individual lights grouped in this manner are major concerns.
Transparent auxiliary screens are already known in the prior art, wherein the light emitted by an auxiliary light source can be propagated, these screens being intended to equip a light, especially a rear light, of an automotive vehicle. Local discontinuities provided in the screen material form light scattering focal points from these screens (see French patent publication No. 2 868 506).
In the German patent application DE 101 01 795, indicator lights are described, especially front indicator lights for automotive vehicles, wherein an auxiliary light source for a position light illuminates an element arranged transversally in the space between the main light and the front cover, and provides thereby illumination in the same direction as that of the main light.
In the French patent application 01 00048, published under the number 2 819 040, an optical or styling component for the illumination or signalling of automotive vehicles is described. This component is made of transparent material, inside which light scattering focal points are situated only at predetermined locations in order to scatter the light emitted by a source associated with the illumination or signalling device in question. This component may constitute the cover of an automotive vehicle lamp, or an insert placed in such a lamp.
In the German patent application DE 103 11 317, a vehicle illumination device is described, comprising a light guide including scattering structures situated essentially at the focal point of reflective surfaces which thus allow scattering of homogeneous illumination.
The applicant has also designed, and described in the patent application FR 0905984 published under the No. 2953781, a novel device for an automotive vehicle light, comprising a transparent optical material and at least one LED type light source arranged to emit light rays propagated inside the thickness of said transparent optical material, essentially comprising:
In these various applications and these various embodiments of light screens scattering the light emitted by at least one LED, inhomogeneities in the scattered light may appear, particularly at the guides with which the curtains or scattering screens may be equipped.
In the case of direct illumination by high- or medium-power LEDs, it is now recognised that it is blinding and should not be generalised in this form.
The applicant further described in the patent application FR 1200281 dated 31.01.2012 an LED illumination device arranged to provide a scattering system helping ensure the uniformity of the light rendition of advantageously multi-LED illumination.
It then appeared to be useful to seek to ensure the uniformity of the light rendition of illumination and signalling devices, and/or to mask any inhomogeneities, and also to provide such devices with a three-dimensional effect enabling personalisation of the light effect and optionally styling effects.
The present invention is intended to provide means for supplying illumination having such a homogeneous rendition and offering users a much less tiring or less blinding rendition than the LED illuminations currently on the market, at the same time that said means are arranged to provide a three-dimensional effect or depth effect for subjects located in the illumination field of the device equipped with said means.
The novel illumination device according to the invention, especially intended, but without being limiting, for a signal lamp and/or exterior or interior ambiance illumination of the passenger compartment of automotive vehicles, comprises a combination of means essentially composed of:
Although the device according to the invention may be of any shape and size, it will be described hereinafter with reference to a device forming an illumination, marking and/or signalling light for automotive vehicles, and with reference to an example of an embodiment wherein said opaque walls are hollow cylinder sections, two in number, having respective radii R and r, arranged parallel to one another, concentrically, and bearing on a PCB whereon n LEDs are placed, regularly or irregularly spaced from one another, whereas said LEDs are arranged so as to emit a light beam directed substantially diametrically in the passage of width R-r thus defined by said opaque plates.
In practice, the opaque walls may define an annular channel or passage of not only circular shape, but also quadrangular, polygonal, or other shapes, regular or not, or a linear or sinuous channel. In the latter case, the walls have identical or homothetic curves, having alternating directions of curvature and with intercalated planar portions.
In one preferred embodiment, the LEDs are arranged substantially regularly according to a geometric figure such as, for example, a circle, on a PCB type substrate.
The elements (b) of said combination of means combine the effects thereof with those of part (a) to provide the particularly attractive effects in terms equally of light intensity and contour precision and originality of the styling effects enabled.
The invention will be understood better, and further aims, advantages and features thereof will emerge more clearly in the light of the description detailed hereinafter of an embodiment considered to be an illustrative example, and alternative or optional embodiments.
The device according to the invention provides the best results thereof in terms of scattering and dispersion of the light from the LEDs when the LEDs or PCB bearing the LEDs are placed at an angle between 0 and approximately 20°, and preferably in an angle of approximately 15°, relative to the transverse section plane of said plates forming a channel for the light from the LEDs.
It was observed that, as such, the light emitted by the LEDs is reflected on the inner walls of the channel defined between two opaque plates and is scattered/dispersed before being routed to the output of the channel from which it is visible by an observer suitably placed in a suitable field of vision.
In addition, the three-dimensional effect provided is permanent, i.e. it appears to the human eye even when the LEDs in question are not switched on. This thus makes it possible to obtain advantageously and economically a 3D effect for the image of the illumination device in question, even when said device is not illuminated, in daylight.
The embodiments described hereinafter are provided merely for illustrative and non-limiting purposes, particularly with reference to the sheets of drawings appended wherein:
As shown in
In the bottom of said housing, a printed circuit board (PCB) 4 comprising LEDs 5 is placed.
In order to be operational, such a device is arranged to be connected to a suitable electric current source.
As can be seen according to
An identical or similar angle may be recommended, but is not necessary for the midplane of the reflector 7 and the semi-transparent screen 8 mentioned above.
Optionally, said reflector or mirror may comprise a reserve (not shown), i.e. a portion of transparent or perforated surface, situated facing at least one LED for the stop function and/or indicator function or reverse light. However, such a reserve is not necessary in the device according to the present invention.
The semi-transparent screen may, to its part, comprise a reserve facing each of the beams from the LEDs or merely facing some thereof.
Provided that the cooling of the LEDs via the rear face thereof is not impeded, and is even advantageously favoured by suitable means known to those skilled in the art, the modular device according to the invention has the remarkable advantage of being capable of being designed so as to be extremely compact and efficient.
The device according to the present invention may comprise, separately or in combination, optional or alternative features, such as in particular:
An end flare 6 of said tubes is optional; it makes it possible to increase the width and the brightness of the beam leaving said tube, and thus give said beam of light rays leaving said tube a width along with exceptional homogeneity, unusual in the current state of the knowledge of those skilled in the art and embodiments that this may infer.
The diameter of said module may be situated, for example, between approximately 10 and 15 centimetres for a main illumination device, such as for example a rear light of an automotive vehicle.
The device according to the invention thus provides the human eye with a view with motion effect comparable to that obtained using the hologram technique, now well-known. It provides a 3D effect with the semi-transparent screen belonging to the sub-assembly (b), and also a styling effect even when the light in question is switched off.
A further aim of the invention consists of an automotive vehicle equipped with at least one device as described herein.
In such a device, the LEDs emit rays which are essentially reflected onto the inner wall of said tubes; after successive reflections of the same light ray, said ray has acquired a beam width and homogeneity means that it provides, for the human eye situated facing the output of said tubes, luminous radiation that remains powerful, but is markedly more homogeneous and less blinding than the radiation originally emitted by the same LED assembly not equipped with the device according to the invention.
For applications in the automotive sector, those skilled in the art will understand that the device according to the invention is positioned in practice at the usual locations of automotive vehicle bodywork. More generally, said device may also be used, with suitable size and configuration adaptations, inside the passenger compartment of automotive vehicles, and even more generally for all household or professional usages, at any location where illumination enhanced in this way by a device according to the invention is sought.
Number | Date | Country | Kind |
---|---|---|---|
1301009 | Apr 2013 | FR | national |
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/FR2014/051044 | 4/30/2014 | WO | 00 |