FR3015633A1 - OPTICAL SYSTEM, DEVICE AND FLOOR - Google Patents

Abstract

The invention relates to an optical system (1) having a body (8) which can be traversed by a light beam from a light source (9) placed in a housing (4) formed in the body (8), said light source having an optical axis (A) substantially parallel to a surface to be illuminated, said light beam passing through the system (1) from a rear area (10) to a front area (11) of said system (1), said system (1) comprising a transmitting lower part (2) capable of at least partially refracting the light beam towards the surface to be illuminated, said lower part (2) being formed between the optical axis (A) of the light source and the surface to be illuminated; an upper part (3) which is at least partially reflective and can reflect at least partially the light beam towards the surface to be illuminated, said upper part (3) being bonded to the lower part (2), the upper (3) and lower parts ( 2) deviating the entire light beam.

Description

FIELD OF THE INVENTION The present invention relates to the field of lighting. More particularly, the invention relates to an optical system, in particular for public lighting streetlights or for the lighting of public buildings. 2. Solutions of the Prior Art It is known, for example for the lighting of public places, such as monuments or roads, to place lighting devices near the surfaces to illuminate. These lighting systems can comprise one or more light sources directed towards the surface to be illuminated, the lighting systems being able to be placed on a support which can be for example a pole of lamp post. However, a recurring problem is to properly orient such lighting systems so that the illumination of the surface to be illuminated is optimal. To remedy this, lighting systems using optical systems such as lenses or mirrors are known, so that the light beam coming from the light source (s) is redirected towards the surface to be illuminated. However, such systems for redirecting the light beam generate a significant loss of brightness which is not satisfactory. Indeed, such a loss of brightness is not suitable in terms of illumination of the surface to be illuminated, and also causes light pollution. In addition, another disadvantage of such solutions is that the redirection of the light beam is unequally made on the surface to be illuminated, which gives an unsatisfactory rendering. 3. OBJECTIVES OF THE INVENTION The object of the invention is in particular to solve at least some of the drawbacks of the prior art. More particularly, it is an object of at least one embodiment of the invention to provide a lighting system which makes it possible to reduce or even eliminate the part of the light beam which is not correctly redirected towards the surface to be illuminated. . Another object of at least one embodiment of the invention is to provide an optical system for obtaining a substantially uniform illumination of the surfaces to be illuminated. Yet another objective of at least one embodiment is to provide such a system which is inexpensive to implement and easy to use. 4. SUMMARY OF THE INVENTION These and other objects, which will become more clearly apparent thereafter, are achieved by an optical system having a body capable of being traversed by a light beam from a source. light source placed in a housing formed in the body, said light source having an optical axis substantially parallel to a surface to be illuminated, said light beam passing through the system from a rear zone 30 to a front zone of said system, said system comprising: a lower part transmitting device capable of at least partially refracting the light beam towards the surface to be illuminated, said lower part being arranged between the optical axis of the light source and the illuminating surface; an upper part at least partially reflective able to reflect at least partially the light beam to the surface to be illuminated, said upper portion being joined to the lower part, the upper and lower parts deviating the entire light beam. Thus, the invention proposes a new and inventive approach that makes it possible to solve at least in part the disadvantages of the prior art. In particular, the invention makes it possible to redirect the light coming from the light source while limiting the loss of illumination by the use of a refractive lower part, which thus directly deviates the portion of the luminous flux which crosses it towards the surface. to illuminate, bonded to a reflective upper part which indirectly deflects the complementary portion of the luminous flux. In addition, such a system can be obtained using simple parts that are inexpensive and simple to implement.

It should be noted that, in the remainder of the patent application, the lower part is the part of the part which is closest to the surface to be illuminated, while the upper part corresponds to the part farthest from the surface. to illuminate, the sum of the two parts forming the entire body of the optical system. In one embodiment of the invention, the lower portion is formed in the rear area of the system. In other words, the lower part is formed in the area closest to the light source. In a variant of the invention, the upper part comprises: a first portion formed in the rear zone of the system, said first portion being connected to the lower part; a second portion formed in the front zone of the system, the second portion being connected to the first portion. According to a particular embodiment of the invention, the housing is formed at the location of the rear zone of the system, between the upper and lower parts. As a result, this allows a light source to be fixedly associated with the optical system by positioning it inside the optical system. In at least one embodiment of the invention, the lower portion has at least one substantially convex profile section. This section may for example be oriented so that for a majority of points of the profile, there is a tangent which is external to the lower part. Thus, it improves the redirection of the portion of light beam passing through this portion. According to one variant, the first portion has at least one substantially convex profile section. This section may for example be oriented such that for a majority of points of the profile, there is a tangent which is outside the first portion. In one embodiment of the invention, the second portion has, in a plane orthogonal to the surface to be illuminated passing through the optical axis of the light source, a symmetrical profile. According to the embodiments, the second portion may have a profile in the form of a free surface.

As a result, this makes it possible to adapt the distribution of the light according to the surface to be illuminated. In one embodiment of the invention, the second portion extends substantially to a substantially planar end located at the optical axis of the light source. In a variant, the upper portion further has a third portion formed in the vicinity of the second portion and connected to said second portion at the end thereof. According to one embodiment of the invention, the optical system further comprises at least one centering pin, said centering pin facilitating the positioning of said system. As a result, the positioning as well as the adjustment of the position of an optical system on a device, for example a lighting device are thereby facilitated. According to a particular embodiment of the invention, the system further comprises means 25 for homogenizing the light reflected by the upper part. Thus, this provides a homogeneous light output of the optical system and to the surface to be illuminated. The invention also relates to a lighting device installed at a distance from a surface to be illuminated, the device comprising: a light source having an optical axis of emission of a luminous flux substantially parallel to the surface to be illuminated; an optical system according to one of the embodiments previously described. In a variant, the device comprises protection means at least partially covering said lighting device. Thus, the optical systems implemented on the lighting device are protected from the various constraints of their evolution environment. The invention also relates to a public street lamp comprising a mast on which several lighting devices are placed according to one of the aforementioned embodiments. According to a variant of the invention, the protection means are connected to the mast by sealed connection means insulating the lighting devices at least at the respective upper surfaces of each of said optical systems. 5. BRIEF DESCRIPTION OF THE DRAWINGS Other features and advantages of the invention will appear more clearly on reading the following description, and the appended drawings among which: FIG. 1 is a rear perspective view of an optical system according to an embodiment of the invention; FIG. 2 is a side sectional view of an optical system according to the embodiment of FIG. 1; FIG. 3 is a bottom view of an optical system according to the embodiment of FIG. 1; and FIG. 4 is a view of a lamp post according to one embodiment of the invention. 6. DETAILED DESCRIPTION With reference to FIGS. 1 to 3, an optical system according to one embodiment of the invention is now presented.

The optical system 1 is adapted to be traversed by a light beam coming from a light source 9 having an optical axis A. This light source 9 and this optical system 1 are placed in such a way that the optical axis A is substantially parallel to the surface illuminate (not shown in the various figures). This surface to be illuminated may for example be the ground or a monument. The light source may for example be composed of one or more light-emitting diodes (otherwise called LEDs or LEDs thereafter). However, it is possible to provide other embodiments in which other lighting means would be used. As illustrated in FIGS. 1 to 3, the optical system 1 has a body 8 and is therefore traversed by a light beam coming from a light source 9. This light beam passes through the optical system 1 from a rear zone 10 to a front zone 11. Here is meant by rear zone 10 the zone which is the furthest left in FIG. 2. Similarly, the front zone 11 of the optical system 1 is the zone which is on the right in FIG. In other words, the rear zone 10 is the zone located near the light source 9 and which is therefore crossed before the front zone 11 which is the zone farthest from the light source 9. This optical system 1 comprises two parts: a lower part 2; and - an upper portion 3. As shown in the figures, the light source 9 is placed in a housing 4 formed in the body 8 of the optical system 1. This housing 4 is formed between the upper 3 and lower 2 parts. As illustrated, the majority of the housing 4 is formed at the top 3 and therefore a smaller part is formed at the bottom. However, one can imagine other embodiments in which the distribution would be different. This housing 4 has, at the level formed in the upper part 3, a cylindrical profile, therefore symmetry of revolution, around the optical axis A of the light source. The part formed in the lower part 2 has a curved profile.

The lower part 2 of the optical system 1 is said to be transmissive, that is to say, it deflects the light rays that pass through it. As a result, the lower part 2 at least partially refracts the light beam coming from the light source 9. More particularly, the lower part 2 refracts the light beam arriving at the lower part (the lower part of the optical system 1 as illustrated in the different figures). Of course, we can imagine other embodiments in which the lower part is only partially refractive.

In this embodiment, the lower portion 2 is integrally formed in the rear area of the optical system. In other words, the entire lower part 2 is included in the rear zone 10 of the optical system 1. However, embodiments could be provided in which at least a portion of the lower part 2 would belong to the front zone 11. of the system. However, it is preferable that at least the majority of the bottom portion be located in the rear area, so as to be placed "close" to the light source and thereby reduce light loss. In the example illustrated in FIGS. 1 to 3, the lower part 2 has a section of substantially convex profile oriented so that for a majority of points of the profile, there is a tangent which is external to the lower part 2. In other words, this lower part 2 is convex towards the outside of the profile of the optical system 1. For its part, the upper part 3 is said to be reflective, that is to say that it reflects the incident rays. on this part. This reflection can for example be achieved by means of mirrors placed on the inner face of this upper surface, vis-à-vis the rays coming from the light source. It should be noted that this upper part 3 is joined to the lower part 2 so that all or at least the vast majority of the light beam coming from the light source 9 is directed towards the surface to be illuminated. However, in a preferred embodiment, the upper part is bonded to the lower part so that these two parts deflect the entire light beam from the light source. In this embodiment, the upper part 2 comprises: a first portion 31 formed in the rear zone 10 of the system 1, this first portion 31 being connected to the lower part 2; a second portion 32 formed in the front zone 10 of the system 1, this second portion 32 being connected to the first portion 31. The first portion 31 has a substantially convex profile section oriented so that for a majority of points of the profile, there is a tangent that is external to the first portion. In other words, and as previously explained for the lower part 2, the first portion 31 illustrated in this embodiment has an outwardly curved profile, and more specifically a slightly curved profile. This first portion also has a symmetry of revolution about the optical axis A of the light source 9. As for the second portion 32, which is connected to the first portion 31 and which is formed in the front zone 10 of the system 1 it has a profile in the form of a free surface. In this example, the free surface, otherwise called "freeform" surface is substantially close to a bell-shaped or Gaussian form. This second portion 32 has, in particular as illustrated in FIG. 3, a symmetrical profile with respect to a plane orthogonal to the surface to be illuminated passing through the optical axis A of the light source 9. As a result, this makes it possible to provide a illumination of the surface to be illuminated substantially symmetric with respect to the optical axis A of the light source 9. The second portion 32 extends substantially to a plane end 321 located at the optical axis A of the light source 9, and parallel to the optical axis. In other words, and based on Figure 2, the second portion 32 extends to this end which forms a horizontal segment, the optical axis A is also arranged horizontally.

In the vicinity of the second portion 32, the upper portion 3 further has a third portion 33 which is connected to the second portion 32 at the location of its end 321. This third portion 33 extends so that the upper portions and lower deviate the entire light beam, or at least a large part of this light beam. In this example, this third portion 33 has a wedge shape, or a substantially symmetrical triangular shape, and thus allows, thanks to this shape, to limit the parasitic lights that could come to find the light beam coming out of the optical system 1. The system optical system further comprises means for homogenization (not shown in the figures) of the light reflected by the upper part 3. In this example, these homogenization means are in the form of a wall implemented between the parties upper 3 and lower 2, at the third portion 33 and parallel to the optical axis A of the light source 9. This wall may comprise for example a plurality of cylindrical lenses arranged regularly on the wall.

It should be noted that, in this example, the upper 3 and lower 2 parts are connected together by means of solidification 15 of the optical system. These solidification means 15 are in this example two ears used on both sides of these two parts, these means not being involved in the deviation of light by the optical system 1. These solidification means 15 can, in addition to increasing the rigidity and strength of the system, improve the manipulation and installation of the optical system on a lighting device. As illustrated in Figures 1 to 3, the optical system 1 comprises at least one centering pin 18 to facilitate the positioning of the optical system on a lighting device. In this example, two centering pins 18 are implemented at the rear zone of the optical system, not far from the housing 4. Of course, it would be possible to provide a different number of centering pins, such as a single piece or well three, depending on the fixation to be ensured. We now present, in connection with Figure 4, a lamp according to one embodiment of the invention. As illustrated in FIG. 4, the lighting street lamp 7 comprises a plurality of lighting devices. Each lighting device comprises: a light source 9, as presented previously in the embodiment illustrated in FIGS. 1 to 3, this light source thus having an optical axis of emission of a luminous flux substantially parallel to the surface to be illuminated (not shown in the figures); an optical system according to the embodiment shown in Figures 1 to 3 and explained in this description. These devices are placed on the lighting lamppost 7 at a masthead 71, itself connected to a mast 70 to place the device away from the surface to be illuminated. For example, if the street lamp is used to illuminate the roadway, the pole 70 of the street lamp allows to place the optical systems 1 and 10 thus the lighting devices at a distance from the ground, which here represents the surface to be illuminated. In this embodiment, the lighting devices are aligned in columns, that is to say in a direction perpendicular to the surface to be illuminated, which corresponds in the case of the roadway to a substantially vertical direction. The street lamp illustrated in this figure 4 thus comprises five lighting devices aligned vertically. Of course, other embodiments could be provided in which the lighting devices would be distributed in line (that is to say substantially parallel to the surface to be illuminated) or in several juxtaposed columns. In the embodiment illustrated in FIG. 4, the devices each comprise a protection means 72 at least partially covering the lighting device. More particularly, and as illustrated in FIG. 4, the protection means consist of "caps". Each cap has a curved profile making it possible to completely cover the upper part of the optical systems 1. Of course, it would be possible to provide embodiments in which the protection means would have another shape, covering a larger or smaller part of the systems. optics. One could even provide an embodiment in which a single means of protection would be implemented for all lighting devices.

It is also possible to provide an embodiment in which the protection means are connected to the mast by means of sealed connection, such as a seal or a flexible plastic part, these connecting means insulating the lighting devices at least at the respective upper parts of each of the optical systems.

Claims (15)

REVENDICATIONS1. Optical system (1) having a body (8) through which a light beam from a light source (9) placed in a housing (4) formed in the body (8) can pass, said light source having an optical axis ( A) substantially parallel to an illuminating surface, said light beam passing through the system (1) from a rear area (10) to a front area (11) of said system (1), said system (1) comprising: - a lower part ( 2) transmitting which can refract at least partially the light beam to the surface to be illuminated, said lower portion (2) being provided between the optical axis (A) of the light source and the surface to be illuminated; an upper part (3) which is at least partially reflective and can reflect at least partially the light beam towards the surface to be illuminated, said upper part (3) being bonded to the lower part (2), the upper (3) and lower parts ( 2) deviating the entire light beam. 2. Optical system according to claim 1, the lower part (2) being formed in the rear zone (10) of said system (1). 3. Optical system according to one of claims 1 or 2, the upper part (3) comprising: - a first portion (31) formed in the rear zone (10) of the system (1), said first portion (31) being Connected to the lower portion (2); a second portion (32) formed in the front zone (10) of the system (1), said second portion (32) being connected to the first portion (31). 4. Optical system (1) according to one of claims 1 to 3, said housing (4) being provided at the location of the rear zone of the system (1) between the upper (3) and lower (2) . 5. Optical system (1) according to one of claims 1 to 4, the lower part (2) having at least a section of substantially convex profile. An optical system (1) according to claim 3, the first portion (31) having at least one substantially convex profile section. 7. Optical system (1) according to claim 3, the second portion (32) having, in a plane orthogonal to the surface 20 to be illuminated passing through the optical axis of the light source (9), a symmetrical profile. An optical system (1) according to claim 6, the second portion (32) having a free-surface profile. An optical system (1) according to claim 3, the second portion (32) extending substantially to a substantially planar end (321) located at the optical axis (A) of the light source (9). ). Optical system (1) according to claim 9, the upper part (3) further having a third portion (33) formed in the vicinity of the second portion (32) and connected to said second portion (32) at the location from its end (321). 11. Optical system (1) according to one of the preceding claims, said system (1) further comprising means for homogenizing the light reflected by the upper part (3). 12. Illumination device installed at a distance from a surface to be illuminated, the device comprising: a light source (9) having an optical axis (A) for emitting a luminous flux substantially parallel to the surface to be illuminated; an optical system (1) according to one of claims 1 to 11. 20 13. Lighting device according to claim 12, said device comprising protection means (72) at least partially covering said lighting device. 25 14. Public street lamp (7) comprising a mat (70) on which are placed a plurality of lighting devices according to one of claims 12 or 13. 15. Lighting post (7) according to one of claims 13 or 14, the protection means (72) being connected to the mast by sealed connection means insulating the lighting devices at least at the upper surface level ( 12) of each of said optical systems (1).