Abstract:
A luminous signaling module, notably for automobile vehicles, comprising: a reflector; a screen disposed in front of the reflector, with a semi-reflecting area; radiating means adapted to emit light rays. The reflector, the screen and the radiating means being arranged in such a manner as to generate a repetitive visual effect of depth. The semi-reflecting area is configured and arranged relative to the radiating means in such a manner that a second portion of the light rays emitted by radiating means do not encounter the semi-transparent area.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to French Application No. 1153699 filed Apr. 29, 2011, which application is incorporated herein by reference and made a part hereof. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The invention relates to a luminous signaling module, notably for automobile vehicles. The invention relates more particularly to a signaling module of the “position” (or “parking light”) type and/or of the “stop” light type for vehicles. The invention relates even more particularly to a signaling device generating an effect of depth in three dimensions thanks to a particular optical device. The invention also relates to a signaling device including such a module. 
         [0004]    2. Description of the Related Art 
         [0005]    The patent document EP 1 916 471 A1, which is equivalent to U.S. Patent Publication 2008/0094842 which is incorporated herein by reference and made a part hereof, describes a rear light of the “parking light” type including a cavity formed by a reflector and a screen disposed at a distance from the reflector. The screen has the particular feature of being semi-transparent, i.e. some of the light rays encountering it are reflected and others are transmitted. The cavity has the particular feature that one of the surfaces of the reflector and of the screen that delimit the cavity is domed. A series of light sources of the light-emitting diode type is disposed at the periphery of the reflector and oriented so as to emit light generally toward the screen. Given the semi-transparent nature of the latter, some of the light rays are transmitted directly and some are reflected toward the reflector. The latter then reflects these rays toward the screen with an offset directed toward the center of the reflector. These rays reflected by the reflector encounter the screen again. In a similar way to the light rays coming directly from the light sources, some of the rays are transmitted by the screen and some are reflected toward the reflector, and so on. The result of these multiple partial transmissions and partial reflections is an optical effect of depth in three dimensions. The lighting or illumination power of the light rays emitted decreases progressively as they are reflected in the cavity. This optical effect is of interest because it enables personalization of the “parking light” attracting the attention of other motorists. It also enables the dissimulation of the “parking light” in a bodywork element, such as an automobile vehicle fender or bumper. It also enables the production of a signaling device that is thin and of small overall size in relation to the depth effect generated. The semi-transparent nature of the screen is obtained by the application of a metallic coating which may give it a metalized appearance similar to that of a bodywork element. The teaching of the above document nevertheless has a major drawback, namely the treatment of the screen intended to render it semi-transparent. The metallic layer applied to the screen will have the consequence that more than 4% of the light is reflected into the cavity and that less than 96% of the rays coming from the light sources will be transmitted (this is without counting the losses inherent to the material of the screen). The level of reflection and transmission may vary and will be directly dependent on the application of the metallic layer. From a process point of view, it is very difficult to guarantee reflection and transmission factors in a narrow tolerance range. The consequence of this is that in the absence of a costly method of treating the screen, the “parking light” equipped with a light source of standard power runs the risk of not satisfying the photometric conditions required by the legislation for a signaling function and also the risk of generating a difference in appearance between the left-hand and right-hand parking lights of the vehicle. For these reasons, this construction is even less suited to a “stop” type function requiring from a photometric point of view a significantly higher lighting power. Moreover, the construction is relatively constraining from the point of view of the number of light sources necessary and also the shape of the light. It is suited to compact shapes as opposed to elongate shapes that would otherwise require too great a number of light sources. 
       SUMMARY OF THE INVENTION 
       [0006]    An objective of the invention is to propose a signaling module alleviating at least some of the drawbacks referred to above. The invention has the more particular objective proposing a signaling module that is of relatively low cost to produce, notably assuring sufficient photometry for a “stop” function and/or allowing some freedom of shape, notably elongate shapes. 
         [0007]    The invention provides a luminous signaling module, notably for automobile vehicles, comprising a reflector with a reflecting surface; a screen disposed in front of the reflector, the screen comprising a semi-reflecting area; radiating means adapted to emit light rays, the reflector, the screen and the radiating means being arranged in such a manner that a first portion of the rays emitted by the radiating means encounters the semi-reflecting area, some of the rays of this first portion being transmitted directly through the semi-reflecting area, other rays of this first portion being reflected by the semi-reflecting area toward the reflector that sends them back again toward the semi-reflecting area, in such a manner as to generate a repetitive visual effect of depth; the module is noteworthy in that the semi-reflecting area is configured and arranged relative to the radiating means in such a manner that a second portion of the light rays emitted by the radiating means does not encounter the semi-transparent area. 
         [0008]    The semi-reflecting layer is such that, on the one hand, some of the rays encountering it are subjected at least once to the chaining of reflections comprising a reflection by the semi-reflecting area, then a reflection by the reflector to reach the reflecting area gain, and, on the other hand, some of the rays encountering it are transmitted through the screen. Some rays may be subjected to this chaining several times. In this case the 3D effect will be reinforced. 
         [0009]    The second portion light rays preferably passes beside the semi-transparent area. 
         [0010]    The radiating means are adapted to emit light. 
         [0011]    The first and/or second portion of the light rays emitted by the radiating means preferably correspond to at least 30%, even 40%, of the light rays emitted. 
         [0012]    In an advantageous embodiment of the invention, the screen forms with the reflector a space in which the reflected rays are propagated, this space being delimited by a surface of the screen and a reflecting surface of the reflector, at least one of these surfaces being such that the rays reflected by the semi-reflecting area from a first location of this area encounter this area again, after reflection at the reflector, at a second location distinct from the first location. 
         [0013]    In an advantageous embodiment of the invention, the screen forms with the reflector a space in which the reflected rays are propagated, this space being delimited by a surface of the screen and a reflecting surface of the reflector, at least one of these surfaces being domed. This is an embodiment that is simple to produce and enables the 3D effect to be enhanced. 
         [0014]    The screen is preferably disposed at a distance from the reflector. 
         [0015]    In another advantageous embodiment of the invention, the radiating means comprise a light source and at least one element for diverting rays emitted by the light source. 
         [0016]    In a further advantageous embodiment of the invention, the deviation element comprises at least one light guide, preferably a longitudinal light guide. 
         [0017]    In a further advantageous embodiment of the invention, the light guide is configured to reflect generally transversely to its longitudinal axis light rays traveling through the guide in such a manner as to form the light rays emitted by the radiating means. 
         [0018]    In a further advantageous embodiment of the invention, the light guide is of generally circular section. 
         [0019]    In a further advantageous embodiment of the invention, the light guide is disposed so that its longitudinal axis is generally parallel to the screen and/or to the reflector. 
         [0020]    In a further advantageous embodiment of the invention, the light guide is disposed along an edge of the reflector. 
         [0021]    In a further advantageous embodiment of the invention, the radiating means are configured so that the light guide is fed with light exclusively at one at least of its ends. 
         [0022]    In a further advantageous embodiment of the invention, the light guide comprises on its exterior surface, preferably on a portion that is opposite the screen, a first row of reflecting facets adapted to reflect generally transversely in a first direction. The first direction is for example perpendicular to the longitudinal axis of the guide in which the light rays travel. 
         [0023]    In a further advantageous embodiment of the invention, the radiating means emit light rays in only one main direction and the semi-transparent area of the screen is disposed in such a manner that one of its edges is the frontier between the first portion and the second portion of the light rays. 
         [0024]    In a further advantageous embodiment of the invention, the light guide comprises on its exterior surface a second row of reflecting facets adapted to reflect light trays traveling through it in a second direction inclined relative to the first direction in such a manner that the rays emitted are directed toward the semi-transparent area. The reflecting facets are preferably adapted to reflect light rays traveling in it generally transversely to the longitudinal axis of the guide. In an advantageous variant, the emitted rays are preferably for the most part directed toward the semi-transparent area. 
         [0025]    In a further advantageous embodiment of the invention, the second row of reflecting facets is disposed generally parallel to the first row. 
         [0026]    In a further advantageous embodiment of the invention, the radiating means comprise two light guides, for example longitudinal light guides, configured to reflect light rays traveling through them in such a manner as to form two beams of parallel light rays in a main illumination direction. In the situation where these guides are longitudinal, they may transmit these rays generally transversely to their longitudinal axis. They may equally be parallel. 
         [0027]    In a further advantageous embodiment of the invention, one of the two light beams for the most part encounters the semi-transparent area and the other of the two light beams is for the most part transmitted directly by the module without encountering the area. 
         [0028]    In a further advantageous embodiment of the invention, the module comprises a light guide, that light guide having a generally flat transversal cross section, an exit surface and a reflection surface configured to reflect toward the exit surface the light rays introduced into the light guide from an internal area of the guide. 
         [0029]    In a further advantageous embodiment of the invention, the reflecting surface of the guide is a curved surface generated by straight line segments perpendicular to the longitudinal axis of the guide. 
         [0030]    In another advantageous embodiment of the invention, the light guide comprises a plurality of longitudinally distributed internal areas for introduction of light. 
         [0031]    The invention also provides a signaling device for automobile vehicles comprising a module of the invention, such as a parking light, a stop light or a turn indicator. 
         [0032]    The invention has the advantage of proposing a signaling device that combines an interesting appearance with performance that is of benefit from the photometric point of view. This photometric performance enables the “parking light” and “stop” functions to be provided in a manner that is original and of benefit from a cost point of view, notably because of a limited lighting power. Moreover, the use of a light guide confers great freedom of design, improved homogeneity of lighting, and a commensurately more interesting appearance. 
         [0033]    These and other objects and advantages of the invention will be apparent from the following description, the accompanying drawings and the appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS 
         [0034]    Other features and advantages of the present invention will be better understood in the light of the description and the drawings, in which: 
           [0035]      FIG. 1  shows a signaling module of a first embodiment of the invention; 
           [0036]      FIG. 2  is a view in horizontal longitudinal section of the light guide of the  FIG. 1  signaling module; 
           [0037]      FIG. 3  shows the image produced by the  FIG. 1  signaling module; 
           [0038]      FIG. 4  shows a signaling module of a second embodiment of the invention; 
           [0039]      FIG. 5  shows a signaling module of a third embodiment of the invention; and 
           [0040]      FIG. 6  shows a signaling module of a fourth embodiment of the invention 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0041]    The various embodiments shown in the figures are intentionally simplified and diagrammatic, with the aim of clarifying the disclosure of the invention. In practice, the various components of the invention could have significantly more complex shapes, notably in relation to various constraints linked to dimensions. 
         [0042]    In the following description, terms qualifying the position of some elements, such as “above”, “below”, “front”, “rear”, “in front of”, “behind”, “horizontal”, “vertical”, “upper”, “lower”, etc. relate to the specific arrangements of the figures. These terms are however not to be interpreted in a strict and absolute manner but rather in a relative manner. The signaling modules described may in practice be oriented differently without in any way departing from the scope of the invention. 
         [0043]      FIG. 1  shows a signaling module  2  conforming to a first embodiment of the invention. The signaling module  2  essentially comprises a light guide  4  extending longitudinally in a manner that is transverse to the general lighting or illumination direction, the latter being oriented horizontally from left to right. The signaling module  2  also comprises a screen  12  with a semi-transparent surface  16  disposed in front of the light guide  4  and a reflector  10  disposed below the light guide  4  and in front of the screen  12 . 
         [0044]    The light guide  4  is of generally circular section and comprises a series of facets  8  on the rear portion of its surface. These facets  8  form reflecting surfaces and are oriented in such a manner as to reflect transversely light rays propagating along the light guide  4 , so that they leave the light guide  8  and propagate in the main illumination direction. These facets  8  are preferably covered with a reflecting coating. The light guide  4  is fed with light rays by one or more light sources  6 , such as light-emitting diodes (LED), from one end. 
         [0045]    When the light source or LED  6  is energized, it emits light rays essentially into a half-space directed toward the end of the light guide  4 . Two light rays are represented in  FIG. 1  and in  FIG. 2  in such a manner as to illustrate the operating principle of the light guide  4  and the signaling module  2 . 
         [0046]    A first ray  18  in a generally horizontal plane enters the light guide  4  with refraction so as to reflected at a point A on the external surface of the light guide  4  in accordance with the principle of total reflection. The surface of the light guide  4  forms a diopter between the material of the light guide  4  having a given refractive index (typically of the order of 1.6 for polycarbonate) and the surrounding air, which has a different refractive index (equal to 1). This refractive index difference of two contiguous media has the consequence that there exists a limit angle of incidence beyond which refraction is impossible and at which total reflection occurs. In the case of a polycarbonate medium surrounded with air, this limit angle is of the order of 38° (according to the Snell-Descartes law). This first ray  18  will then be directed toward one of the reflecting facets  8  to be reflected there in a direction transverse to the longitudinal axis of the light guide  4 , to encounter the surface of the light guide  4  at a low angle of incidence less than the limit angle of incidence (see above), and exit the light guide  4 , possibly with slight refraction. This first ray  18  is in a generally horizontal plane and is propagated directly toward the space to be lit or illuminated, passing over the upper edge of the screen  12 . 
         [0047]    The ray  20  also emitted by the LED  6  is oriented in a direction having a vertical component. It enters the light guide  4  with slight refraction and is propagated to a point B on the surface of the light guide  4 . In a similar way to the first ray  18 , according to the principle of total reflection, the ray  20  will be reflected toward one of the reflecting facets  8 . It will then be reflected at the facet and then directed toward the front surface of the light guide  2 . In a similar way to the first ray  18 , it will encounter the front surface of the light guide  2  with a very small angle of incidence and because of this leave the light guide  2  with slight refraction and be propagated toward the semi-reflecting surface  16  of the screen  12 . As may be seen in  FIG. 2 , which is a view in section on a longitudinal horizontal plane, the ray  20  evolves similarly to the first ray  18  in a horizontal plane. As may be seen in  FIG. 1 , which is a perspective view, because of its inclination relative to the horizontal plane, the ray  20  leaving the LED  6  evolves in an inclined plane and is then reflected by the reflecting facet  8  toward a low portion of the front surface of the light guide  4 . 
         [0048]    It should be noted that the propagation of light rays along a light guide and the exit of these rays by means of reflecting facets notably of the prismatic type is well known in itself to the person skilled in the art. 
         [0049]    The two rays  18  and  20  are two illustrative examples of the rays emitted by the LED  6  and transmitted by the light guide  4 . The light emitted by the LED  6  and transmitted by the light guide  4  of course comprises a beam constituted of a multitude of light rays that travel along the light guide  4  undergoing a series of reflections to leave it in a manner that is homogeneous along its length. Some of the rays leaving it will leave the light guide  4  in a direction close to the main lighting direction and because of this pass over the semi-reflecting surface  16  of the screen  12 . Others of the leaving rays will leave the light guide  4  in directions inclined downward relative to the main lighting direction and will thus encounter the semi-reflecting surface  16 . 
         [0050]    The rays encountering the semi-reflecting surface  16  of the screen  12 , such as the ray  20 , will be partially transmitted and partially reflected. The ray  20  representative of these rays is subject to partial reflection by the semi-reflecting surface  16 . The reflected portion of the ray  20  is returned toward the screen  12  by the reflector  10  to be partially transmitted  22  and reflected again. This reflected portion  22  of the ray is sent back toward the screen  12  by the reflector  10  to be partially transmitted again, and so on. Consequently, some of the light rays encountering the semi-transparent portion, preferably more than 4% of the rays encountering this surface, are reflected toward the reflector by the screen  12 . This reflected portion is then totally reflected or quasi-totally reflected toward the screen  12  by the reflecting surface  14  of the reflector  10 . In a similar way to the previous rays, these rays will then be partially transmitted by the semi-transparent screen  12  and partially reflected again toward the reflector  10 . This reflection and shifting toward the center of the cavity is assured by the domed nature of the reflector  10 . It should be noted that the surface of the reflector  10  could alternatively be generally plane and the internal surface of the screen  12  delimiting the cavity would then be domed. Considering a combination of domed surfaces at the level of the screen  12  and the reflector  10  may equally be envisaged. 
         [0051]    The screen  12  may be produced using a transparent material routinely used, such as certain plastics or glass, for example. One of its surfaces, the external or internal surface, is rendered semi-transparent by application of a coating that is typically partially reflecting. The coating is usually a metallic coating such as aluminum or a stainless metal applied by a vacuum vapor phase deposition technique. Various methods of application of the coating known to the person skilled in the art may be used. The reflection factor of the coating is in the range 20% to 60%, for example. 
         [0052]    The rays being propagated directly toward the space to be lit or illuminated without encountering the semi-reflecting surface  16  will constitute a first lighting beam  26  that may correspond to a “stop” function. The rays encountering the semi-reflecting surface  16  will suffer losses on successive partial transmissions and may thus correspond to a signaling function of the “parking light” type. From a regulations point of view, the lighting power required for the “parking light” function is less than that required for the “stop” function, by a ratio in excess of ten (10). It follows that the module described above is particularly well suited to such an application. 
         [0053]      FIG. 3  shows the image produced by the  FIG. 1  module. The upper portion  26  of the beam corresponds to rays transmitted directly without encountering the semi-reflecting surface. The image produced comprises a band  30  corresponding to the light guide  4 . The multitude of reflecting facets of the light guide  4  ensures a certain level of homogeneity in the image produced. Notably as a function of the size of these facets, the image could have a greater or lesser homogeneity. 
         [0054]    The lower portion  28  generates a three-dimensional effect. The image produced comprises a first band  32  essentially corresponding to the band  30  but with a lower power level because of losses inherent to transmission through the semi-reflecting surface. It also comprises a series of bands  34  corresponding to the initial band  32  that are repeated and become finer and finer, thus generating the 3D effect. The level of lighting power also decreases progressively because of losses linked to transmission through the semi-reflecting surface. 
         [0055]    The LED or LEDs  6  are preferably of controlled current (PWD (Pulse Width Modulation)) type. The relation between the voltage and the supply current of the emissive semiconductors (the LEDs) is not linear. Thus a small increase of voltage applied to the LED  6  may lead to a high increase in the current and thus in the luminous flux emitted. The brightness of the LEDs  6  to be controlled necessitates a current that remains constant whatever the input voltage. 
         [0056]    In practice, the two parts  26  and  28  of the light beam produced are always present when the light source is or the light sources are supplied with electrical current. As a function of the power supplied, the module in question could provide the “stop” and “parking light” functions. At a low power supply level, the portion  26  of the beam coming directly from the light guide  4 , i.e. without undergoing partial reflection, will produce a first lighting level sufficient from a photometric point of view and a regulations point of view for the “parking light” function. At a higher level of supplied power, the portion  26  of the beam coming directly from the light guide  4  will produce a higher level of lighting corresponding from a photometric and regulations point of view to the requirements of the “stop” function. The three-dimensional part  28  will then produce a lighting level greater than for the “parking light” function alone. This lighting level alone will then be sufficient from a regulations point of view for the “parking light” function. The module described above thus enables a two-fold “stop” and “parking light” function to be offered with a three-dimensional effect without requiring too high a lighting power at the level of the light sources. This is essentially caused by the fact that a portion of the beam leaving the light guide  4  is propagated directly toward the space to be illuminated without suffering any loss. The construction of the module with the light guide  4  confers great freedom from a design point of view. The construction of the module is also particularly simple and of relatively low cost. 
         [0057]    In the  FIG. 1  configuration, the screen  12  is positioned in such a manner that its upper edge is approximately half way up the light guide  4 , so that the upper part of the light beam leaving the guide is propagated directly toward the space to be illuminated without encountering it. The semi-reflecting surface  16  extends as far as the upper edge, thus forming a cut-off edge between the beams transmitted directly and partially reflected. It is to be noted that the screen  12  may comprise a transparent part and a semi-transparent part, the transparent part then being able to extend toward the upper part of the beam in such a manner as to have the rays of the upper portion  26  of the beam produced pass through it. 
         [0058]    Other embodiments of the invention will be described with reference to  FIGS. 4 to 6 . These examples constitute variants of the  FIG. 1  example. Numerous components of the modules shown in these figures correspond to those of  FIG. 1 . Consistent numbering has been adopted to designate these various components, the reference signs in  FIG. 4  corresponding to those of  FIG. 1  except that they are increased by 100. The same applies to  FIG. 5 , where they are increased by 1000, and  FIG. 6 , where they are increased by 10 000. Numbers specific to each embodiment have been employed to designate components not present in  FIG. 1 . 
         [0059]      FIG. 4  shows a second embodiment of a signaling module of the invention. It is distinguished from the first embodiment essentially in that the radiating means  104  comprise two light guides  141  and  142  disposed parallel to each other and one above the other. Each of these light guides  141 ,  142  specifically comprises at one of its ends at least its own light source constituted of one or more LEDs  161  and  162 . Each of these light guides  141 ,  142  also comprises a series of reflecting facets  181  and  182 , in a similar way to the  FIG. 1  light guide. These facets are disposed in such a manner as to reflect rays propagating along the light guides  141 ,  142  transversely toward the space to be illuminated. 
         [0060]    The rays emitted by the LED  161  of the upper light guide  141  are propagated along the upper light guide  141  and are reflected homogeneously in a direction generally perpendicular to the longitudinal axis of the upper light guide  141 . A ray  118  is represented in order to illustrate the principle of reflection. The upper light guide  141  and its reflecting facets  181  are configured in such a manner that most of the rays leaving the upper light guide  141  are oriented in the main illumination direction. These rays, like the first ray  18 , are propagated directly toward the space to be illuminated without encountering the semi-reflecting surface  116  of the screen  112 . 
         [0061]    The phenomena described for the upper light guide  141  apply equally to the lower light guide  142 . A ray  120  is represented in order to illustrate the phenomena of reflection in a similar way. Most of the rays leaving the lower light guide  142  encounter the semi-reflecting surface  116 . These rays are then partially transmitted and partially reflected toward a reflector  110 . The latter has a non-plane surface, for example a curved concave surface. The reflection-transmission of rays at the semi-reflecting surface  116  and the pure reflection at the reflector  110  generate a 3D effect in a similar way to the module of the first embodiment of the invention. More particularly, the ray  120  leaving the guide is partially transmitted by the screen  112  and partially reflected toward the reflector  110  so as thereafter to be partially transmitted by the screen as a ray  122  and partially reflected toward the reflector  110  so as thereafter to be again partially transmitted as a ray  124 , and so on. 
         [0062]    Thus the  FIG. 4  module produces two independent beams, namely a first beam  126  the rays of which leaving the upper light guide  141  are propagated directly toward the space to be illuminated without encountering the semi-reflecting surface  116 , and a second beam  128  passing through the semi-reflecting surface  116 . 
         [0063]    The first beam  126  may consequently correspond to a “stop” function and the second beam  128  to a “parking light” function. In this case, the light sources  161  and  162  are energized independently. Energizing the light source  162  of the second beam  128  will then provide the “parking light” function with a 3D effect and energizing the light source  161  of the first beam  126  will provide the “stop” function. The “stop” function could thus have no three-dimensional effect. It should nevertheless be noted that it is possible to provide for coupled energization in order for the three-dimensional effect to be present in both functions. 
         [0064]      FIG. 5  shows a third embodiment of a signaling module of the invention. It is similar to the first embodiment but with a major difference being the type of light guide. The light guide of the first embodiment ( FIG. 1 ) is of generally circular section and propagates the light along its longitudinal axis. In the case of  FIG. 5 , the light guide  1004  is different to the degree that it receives light from an internal area and not from one end. More particularly, the light guide  1004  comprises a series of orifices or wells  1041 ,  1042  distributed over its length. A light source  1061 ,  1062  is disposed in or near each orifice  1041 ,  1042 . The rays emitted by one of the light sources  1061  in lateral directions relative to the main lighting direction and rear directions are reflected by a reflecting surface  1043  of the light guide  1004  in a direction generally aligned with the main lighting direction. This surface is generally defined by generatrices perpendicular to the longitudinal axis of the light guide  1004 . It has a curved profile in such a manner as to be able to assure reflection of most of the rays propagating in a sector of more than 180°, this sector being essentially oriented toward the rear. These rays are reflected in such a manner as to encounter the exit surface substantially perpendicularly. The surface  1043  consequently has a succession of curved profiles, each of these profiles extending around a light source. The light guide  1004  is of generally straight cross section. The exit face of the light guide  1004  also has a generally straight cross section. 
         [0065]    The operating principles and the structural details of such a light guide are well known in themselves to the person skilled in the art, notably from the patent document EP 1 881 263 A1, which was also published as U.S. Patent Publications 2008/0019139, 2010/0238675 and 2012/0075876 and also as U.S. Pat. Nos. 7,731,400 and 8,070,336, all of which are incorporated herein by reference and made a part hereof. 
         [0066]    In a similar way to the first embodiment of the invention ( FIG. 1 ), some of the rays emitted by the light guide essentially in the main illumination direction are propagated directly toward the space to be illuminated without encountering the semi-reflecting surface  1016  and others of these rays encounter the semi-reflecting surface  1016 . Four rays are represented in order to show clearly the phenomena of light propagation. A first ray  1181  is emitted by the light source  1061  in a lateral direction of the module and directed slightly upward. This ray encounters the reflecting surfaces  1043  at a given point situated in an upper half of the surface. The ray is reflected toward the exit surface with a low angle of incidence. The ray exits the surface with little or no refraction and passes above the upper edge of the semi-reflecting surface  1016  to be propagated directly toward the space to be illuminated. The same goes for the second ray  1182  emitted by the same light source in a direction globally opposite that of the first ray  1181  and also directed slightly upward. This first ray  1181  is reflected by the reflecting surface  1043 , exits the light guide  1004  and is propagated directly toward the space to be illuminated. The third ray  1201  is emitted in a direction close to that of the first ray  1181  but inclined slightly downward. This third ray  1201  will be reflected by the reflecting surface  1043  in a similar way to the first ray  1181  in a direction inclined slightly downward. On exiting the light guide  1004  with this inclination, the third ray  1201  will encounter the semi-reflecting surface  1016  and be subjected to a combination of partial transmission and partial reflection by the reflector  1010  in a similar way to the modules of  FIGS. 1 and 4 . 
         [0067]    Because of its enveloping shape and the profile chosen for it, the reflecting surface  1043  has the capability to “recover” by reflection most of the rays emitted by the light source and being propagated in the light guide  1004  in a radial manner within a sector of more than 180°, preferably a sector greater than 220°, even more preferably a sector greater than 270°, generally directed toward the rear. 
         [0068]    Some of the rays exiting the waveguide will consequently be propagated directly toward the space to be illuminated without encountering the semi-transparent surface and some other rays will be subjected to a combination of partial transmission and partial reflection, thereby generating a three-dimensional image of lesser photometric power. Given the similarity of the modules from  FIGS. 5 and 1 , the remarks made in relation to  FIG. 1  in relation to the “stop” and “parking light” functions and the energization of the light sources apply equally to  FIG. 5 . 
         [0069]      FIG. 6  shows a fourth embodiment of a signaling module of the invention. It is notably similar to that of  FIG. 1  with the main difference that the light guide comprises a second row of reflecting facets so as to reflect some of the rays being propagated in the guide in a direction inclined downward. The light guide  10004  from  FIG. 6  is similar to that from  FIG. 1 . It is of generally circular section and comprises a first row of reflecting facets  10081  comparable to the row of facets  8  from  FIG. 1 . It further comprises a second row of reflecting facets  10082  offset angularly relative to the first row of reflecting facets  10081 . The first row of reflecting facets  10081  reflects some of the rays being propagated along the light guide  10004 , in a direction generally transverse, preferably perpendicular, to the longitudinal axis of the light guide  10004  and generally aligned with the main illumination direction. The second row of reflecting facets  10082  is disposed parallel to the first row of reflecting facets  10081 , in an angular position offset in such a manner as to reflect other rays being propagated along the light guide  10004 , in a direction generally transverse, preferably perpendicular, to the longitudinal axis of the light guide  10004  and inclined relative to the main illumination direction. These rays reflected by the second row of reflecting facets  10082  encounter the semi-transparent surface  10016  of the screen  10012 . These rays are subject to a successive combination of transmission and partial reflection by the screen  10112  and pure reflection by the reflector  10010 . 
         [0070]    Two rays  10018  and  10020  are represented in order to illustrate the principles of light propagation and reflection. The first ray  10018  is comparable to the first ray  18  from  FIG. 1 . It is emitted by the LED  10006  in a generally horizontal plane. It encounters the surface of the light guide  10004  and is there subjected to reflection based on the principle of total reflection thereafter to encounter a reflecting facet  10081  and to be reflected there in a direction generally perpendicular to the longitudinal axis of the light guide  10004 . The first ray  10018  remains approximately in the horizontal plane and exits the light guide  10004 , being propagated along the main lighting direction directly toward the space to be illuminated without encountering the semi-transparent surface. The second ray  10020  emitted by the LED  10006  is inclined upward and is subjected to two successive reflections at the surface of the waveguide, based on the principle of total reflection. It then encounters a reflecting facet  10082  of the second row. The angle of this facet to the first row of reflecting facets  10081  has the effect of diverting the ray  10020  slightly downward and therefore toward the semi-reflecting surface  10016  of the screen  10012 . There then follows a succession of partial reflections/transmissions by the semi-reflecting surface  10016  and total reflections by the reflector  10010 . The latter is inclined relative to the semi-reflecting surface in such a manner as to influence the interaction with the surface and to generate a three-dimensional effect. It could equally be domed in a concave or convex manner as in the modules of  FIGS. 1 and 4 . 
         [0071]    In a similar way to the remarks made for the  FIG. 1  example, the upper portion  10026  of the beam coming from the first row of reflecting facets  10081  without being subjected to partial transmission enables the assurance of a lighting power conforming to the photometric requirements for the “stop” function. The lower portion  10028  of the beam coming from the second row of facets  10082  produces an image with a three-dimensional effect of lower lighting power, notably for the “parking light” function in combination with the “stop” function. The “parking light” function could be assured by the two portions  10026  and  10028  if the light source or sources is or are supplied with a lower power. 
         [0072]    While the system and apparatus herein described constitute preferred embodiments of this invention, it is to be understood that the invention is not limited to this precise system and apparatus, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.