Lighting device and outdoor street lamp provided with such a device

Abstract

The present invention relates to a lighting device (4) having at least three LEDs (7, 8, 9), each LED (7, 8, 9) is selected only from the group consisting of: - a first LED (7) emitting green light with a nominal wavelength of 513 nanometres to 543 nanometres; - a second LED (8) emitting amber light with a nominal wavelength of 583 nanometres to 605 nanometres; and - a third LED (9) emitting red-orange light with a nominal wavelength of 610 nanometres to 635 nanometres, the lighting device (4) comprising M first LEDs (7), N second LEDs (8) and P third LEDs (9), with M ≥ 1, N ≥ 1 and P ≥ 1. The invention also relates to an outdoor street lamp having at least one such lighting device (4).

Description

[0001] DESCRIPTION

[0002] TITLE: Lighting device and outdoor lamp post equipped with such a device

[0003] FIELD OF THE INVENTION

[0004] The present invention relates to the field of lighting, and in particular to a lighting device and to an outdoor lamppost equipped with such a device.

[0005] STATE OF THE ART

[0006] Lighting devices are known, for example from document US 2017 / 0079108 A1, which emit light in the spectrum visible to a human observer. Such lighting devices comprise, for example, a plurality of LEDs, also called light-emitting diodes, which make it possible to generate high-intensity lighting over a broad spectrum visible to the human eye while limiting the power consumption of these lighting devices.

[0007] However, these lighting devices affect the biological rhythm of plants and animals. Thus, these lighting devices affect plant growth by causing artificial photosynthesis, not resulting from sunlight. Furthermore, these lighting devices harm animals, such as insects, birds, fish, and mammals. Indeed, these lighting devices disrupt their growth, orientation, phototaxis, or chronobiological cycle, such as their circadian rhythm. Indeed, the generation of light by these lighting devices, especially during the night, forces photosynthesis in plants and disrupts animals.

[0008] STATEMENT OF THE INVENTION

[0009] The invention aims in particular to provide a lighting device which provides comfortable lighting for humans while avoiding encouraging photosynthesis in plants and limiting disturbances to animals.

[0010] According to a first aspect, the invention proposes a lighting device comprising at least three LEDs, each LED being chosen only from the group comprising, preferably consisting of:

[0011] - a first LED emitting green light with a nominal wavelength between 513 nanometers and 543 nanometers,

[0012] - a second LED emitting amber light with a nominal wavelength between 583 nanometers and 605 nanometers, and

[0013] - a third LED emitting red-orange light with a nominal wavelength between 610 nanometers and 635 nanometers, the lighting device comprising M first LEDs, N second LEDs and P third LEDs, with M > 1, N > 1 and P > 1.

[0014] Thus, the lighting device provides comfortable lighting for humans while avoiding encouraging photosynthesis in plants and limiting disturbances to animals. More specifically, the use of three types of LEDs of different colors, preferably only three types of LEDs of different colors, makes it possible to obtain light from three colors, which is comfortable for humans, because humans are trichromats. In addition, the overall color of the light emitted by the lighting device is golden for a human observer, and is thus close to the color of the light emitted by a high-pressure sodium lamp, widely used in urban lighting. The substitution of such a high-pressure sodium lamp by a lighting device according to the invention does not change the visual habits of the human observer accustomed to nocturnal urban outdoor lighting by high-pressure sodium lamps.Furthermore, the light emission spectrum of the lighting device avoids encouraging photosynthesis in plants, in particular because it is located almost outside the absorption spectrum of chlorophyll a and mainly outside the absorption spectrum of chlorophyll b. Finally, the light emission spectrum of the lighting device limits disturbances to animals, particularly insects.

[0015] According to a second aspect, the invention also proposes an outdoor lamppost, comprising a mast carrying a head, the head comprising at least one lighting device as previously described.

[0016] Indeed, the overall color of the light emitted by the lighting device is golden, and is thus close to the color of the light emitted by a high-pressure sodium lamp, widely used in urban lighting. The substitution of such a high-pressure sodium lamp by a lighting device according to the invention does not modify the visual habits of a human observer accustomed to nighttime urban outdoor lighting by high-pressure sodium lamps. Thus, an outdoor street lamp equipped with the lighting device provides comfortable lighting for humans.

[0017] The invention is advantageously and optionally supplemented by the following characteristics, taken alone or in any of their technically possible combinations: - The lighting device is such that:

[0018] - all of the first M LEDs have a relative light intensity between 0.39 and 0.43,

[0019] - the set of N second LEDs has a relative luminous intensity of between 0.57 and 0.68, preferably between 0.62 and 0.68, and

[0020] - the set of P third LEDs has a relative luminous intensity equal to 1.0. Thus, the overall color of the light emitted by the lighting device is golden for a human observer, and is therefore comfortable for humans.

[0021] - The lighting system is such that:

[0022] - all of the first M LEDs have a relative luminous intensity equal to 0.41,

[0023] - the set of N second LEDs has a relative luminous intensity equal to 0.65. Thus, the overall color of the light emitted by the lighting device is particularly golden for a human observer, and is therefore particularly comfortable for humans.

[0024] - Each of the N second LEDs emits amber light with a nominal wavelength between 583 nanometers and 595 nanometers.

[0025] - Each of the third P LEDs emits red-orange light with a nominal wavelength between 620 nanometers and 635 nanometers, preferably between 620 nanometers and 632 nanometers.

[0026] - Each LED has a bandwidth between 10 nanometers and 70 nanometers. Thus, the limited bandwidth of each LED avoids encouraging photosynthesis in plants and limits disturbance to animals. Preferably, the bandwidth is the spectral bandwidth at 50% of the light peak, also known as Full Width at Half Maximum or FWHM.

[0027] - Each LED has a bandwidth of between 10 nanometers and 40 nanometers, preferably between 16 and 30 nanometers. Thus, the particularly limited bandwidth of each LED particularly avoids encouraging photosynthesis in plants and particularly limits disturbances to animals.

[0028] - The lighting device is such that P < M < N, preferably such that P < M < N. Indeed, LEDs emitting high-power amber light are expensive compared to LEDs emitting green light and LEDs emitting red-orange light. Thus, it is advantageous to use a larger number of LEDs emitting lower-power amber light in order to limit the cost of the lighting device.

[0029] - The lighting device is such that N = 2 x M and / or N = 2 x p. Thus, the distribution of the LEDs is facilitated with a view to the emission of homogeneous light by the lighting device.

[0030] - The lighting device is such that M = P and N = 2 x M. Thus, the distribution of the LEDs is particularly facilitated with a view to the emission of homogeneous light by the lighting device.

[0031] - The lighting device is such that M = P = 7 and N = 14. Thus, such a lighting device presents a good compromise between manufacturing and assembly costs and homogeneity of the light emitted by the lighting device.

[0032] - The lighting device is such that the LEDs are coplanar. This makes it easier to arrange the LEDs so that the lighting device emits uniform light.

[0033] - The lighting device is such that the LEDs are oriented parallel to each other. This makes it easier to arrange the LEDs so that the lighting device emits uniform light.

[0034] - The lighting device is such that the LEDs emit in principal directions parallel to each other. This makes it easier to arrange the LEDs so that the lighting device emits a homogeneous light.

[0035] - The lighting device has a support, with the LEDs arranged on the support. Thus, the design and handling of the lighting device are simplified.

[0036] - The lighting device is such that the LEDs are regularly distributed on the support, preferably the LEDs being distributed symmetrically relative to the center of the support.

[0037] - For each second LED, at least one first LED and at least one third LED are the LEDs closest to the second LED. Thus, the light emitted by the lighting device has a color distribution whose homogeneity is improved.

[0038] - The lighting device is configured to emit light at a color temperature of between 2200 and 2330 Kelvin, preferably between 2230 and 2330 Kelvin, more preferably equal to 2280 Kelvin. Thus, the overall color of the light emitted by the lighting device is particularly golden for a human observer, and is therefore particularly comfortable for humans.

[0039] - The outdoor lamppost is configured to provide outdoor lighting, preferably at night.

[0040] - The outdoor lamppost is configured to provide outdoor lighting in an urban environment.

[0041] - The outdoor lamp post consists of three aligned lighting devices, preferably side by side. Thus, the luminous flux emitted by each lighting device can be limited and the production of the lighting device is modular, which reduces the overall cost of the outdoor lamp post.

[0042] - The outdoor lamp post is configured to emit a luminous flux of between 7500 and 8000 lumens, preferably equal to 7800 lumens. Thus, the luminous flux is significant, and is sufficient for example for night-time urban outdoor lighting.

[0043] - The mast has a height between 4 and 8 meters, preferably equal to 8 meters. Thus, the lighting area provided by the outdoor lamppost is significant.

[0044] - The head has a housing. This protects the lighting device from bad weather or damage.

[0045] - The support is housed in the case.

[0046] - The case is made of aluminum.

[0047] - The housing houses a power supply unit.

[0048] DESCRIPTION OF FIGURES

[0049] Other characteristics, aims and advantages of the invention will emerge from the detailed description below, which is purely illustrative and non-limiting, and which must be read in conjunction with the appended drawings, given as non-limiting examples and in which: Figure 1 is a schematic side view of an embodiment of an outdoor lamppost; Figure 2 is a schematic perspective view of an embodiment of a head of the outdoor lamppost shown in Figure 1; Figure 3 is a schematic bottom view of an embodiment of a lighting device of the head shown in Figure 2; Figure 4 presents a graph representing the light emission spectrum of a lighting device according to the invention, in particular of the lighting device shown in Figure 3, the graph having the wavelength in nanometers as its abscissa and the relative light intensity as its ordinate.

[0050] Throughout the figures, similar elements are designated by identical references.

[0051] DETAILED DESCRIPTION OF THE INVENTION

[0052] Figure 1 shows an embodiment of an outdoor lamp post 1. The outdoor lamp post 1 comprises a mast 2 and a head 3. The mast 2 carries the head 3. The head 3 comprises at least one lighting device 4.

[0053] Advantageously, the outdoor lamp post 1 is configured to emit a luminous flux of between 7500 and 8000 lumens, preferably equal to 7800 lumens.

[0054] Advantageously, the outdoor lamppost 1 is configured to provide outdoor lighting, preferably at night.

[0055] Preferably, the outdoor lamp post 1 is configured to provide outdoor lighting in an urban environment.

[0056] This makes it possible to use the outdoor lamppost 1 at night in an urban environment.

[0057] Advantageously, mast 2 has a height between 4 and 8 meters, preferably equal to 8 meters.

[0058] Advantageously, the head 3 comprises a housing 5. Preferably, the housing 5 is made of aluminum.

[0059] Advantageously, the housing 5 houses a power supply unit 6. The power supply unit 6 powers the lighting device 4.

[0060] Advantageously, the housing 5 comprises a tube 5a. Preferably, the tube 5a is engaged in the mast 2, in order to allow the head 3 to be held in position on the mast 2. The tube 5a is hollow in order to allow the passage of electrical power supply cables extending through the mast 2 into the housing 5. Advantageously, the electrical power supply cables supply the lighting device 4 via the electrical power supply unit 6.

[0061] Figure 2 shows an embodiment of the head 3. In this example, the head 3 comprises three lighting devices 4.

[0062] Advantageously, the three lighting devices 4 are aligned. Preferably, the three lighting devices 4 are adjacent to each other.

[0063] Figure 3 represents an embodiment of the lighting device 4.

[0064] The lighting device 4 comprises at least three LEDs 7, 8, 9.

[0065] Advantageously, each LED 7, 8, 9 is chosen only from the group comprising:

[0066] - a first LED 7 emitting green light with a nominal wavelength between 513 nanometers and 543 nanometers,

[0067] - a second LED 8 emitting an amber light with a nominal wavelength between 583 nanometers and 605 nanometers, and

[0068] - a third LED 9 emitting a red-orange light with a nominal wavelength between 610 nanometers and 635 nanometers.

[0069] Advantageously, the lighting device 4 comprises M first LEDs 7, N second LEDs 8 and P third LEDs 9, with M > 1, N > 1 and P > 1.

[0070] In other words, the lighting device 4 comprises exactly M first LEDs 7, exactly N second LEDs 8 and exactly P third LEDs 9, with M > 1, N > 1 and P > 1.

[0071] Preferably, each LED 7, 8, 9 is chosen only from the group consisting of:

[0072] - a first LED 7 emitting green light with a nominal wavelength between 513 nanometers and 543 nanometers,

[0073] - a second LED 8 emitting an amber light with a nominal wavelength between 583 nanometers and 605 nanometers, and

[0074] - a third LED 9 emitting a red-orange light with a nominal wavelength between 610 nanometers and 635 nanometers.

[0075] Thus, each LED 7, 8, 9 is either a first LED 7, or a second LED 8, or a third LED 9. For example, each of the first M LEDs 7 is an OSRAM OSLON® SSL 80, GT CS8PM1.13 LED, preferably conforming to its datasheet version 1.16.

[0076] Advantageously, each of the N second LEDs 8 emits an amber light with a nominal wavelength between 583 nanometers and 595 nanometers.

[0077] For example, each of the N second LEDs 8 is an OSRAM OSLON® SSL 80, GY CS8PM1.23 LED, preferably conforming to its datasheet version 1.6.

[0078] Advantageously, each of the P third LEDs 9 emits a red-orange light with a nominal wavelength of between 620 nanometers and 635 nanometers, preferably between 620 nanometers and 632 nanometers.

[0079] For example, each of the third P LEDs 9 is an OSRAM OSLON® SSL 80, GR CS8PM1.23 LED, preferably conforming to its datasheet version 1.8.

[0080] Advantageously, the lighting device 4 is such that:

[0081] - all of the first M LEDs 7 have a relative light intensity between 0.39 and 0.43,

[0082] - the set of N second LEDs 8 has a relative light intensity of between 0.57 and 0.68, preferably between 0.62 and 0.68, and

[0083] - the set of P third LEDs 9 has a relative luminous intensity equal to 1.0.

[0084] Preferably, the lighting device 4 is such that:

[0085] - all of the first M LEDs have a relative luminous intensity equal to 0.41,

[0086] - the set of N second LEDs has a relative luminous intensity equal to 0.65.

[0087] Advantageously, the lighting device 4 is configured to emit light at a color temperature of between 2200 and 2330 Kelvin, preferably between 2230 and 2330 Kelvin, more preferably equal to 2280 Kelvin.

[0088] Advantageously, each LED 7, 8, 9 has a bandwidth of between 10 nanometers and 70 nanometers. Preferably, each LED 7, 8, 9 has a bandwidth of between 10 nanometers and 40 nanometers, more preferably between 16 nanometers and 30 nanometers.

[0089] Preferably, the lighting device 4 is such that P < M < N, more preferably such that P < M < N. Preferably, the lighting device 4 is such that N = 2 * M and / or N = 2 x p. More preferably, the lighting device 4 is such that M = P and N = 2 x M. Even more preferably, the lighting device 4 is such that M = P = 7 and N = 14. Thus, for example, the lighting device 4 comprises exactly: 7 first LEDs 7, 14 second LEDs 8 and 7 third LEDs 9.

[0090] Advantageously, the lighting device 4 comprises a support 10. Preferably, the LEDs 7, 8, 9 are arranged on the support 10.

[0091] Preferably, the support 10 is housed in the housing 5.

[0092] Advantageously, the lighting device 4 is such that the LEDs 7, 8, 9 are coplanar.

[0093] Advantageously, the lighting device 4 is such that the LEDs 7, 8, 9 are oriented parallel to each other.

[0094] Advantageously, the lighting device 4 is such that the LEDs 7, 8, 9 emit in main directions parallel to each other.

[0095] Advantageously, the lighting device 4 is such that the LEDs 7, 8, 9 are regularly distributed on the support 10. Preferably, the LEDs 7, 8, 9 are distributed symmetrically relative to the center of the support, in particular without taking into consideration the type of LED, namely first LED 7, second LED 8 or third LED 9.

[0096] Preferably, for each second LED 8, at least one first LED 7 and at least one third LED 9 are the LEDs closest to the second LED 8.

[0097] Figure 4 shows a graph representing the light emission spectrum of the lighting device 4. The light emission spectrum of the lighting device 4 is thus not significant, for example of relative light intensity greater than 0.2, or even greater than 0.1, neither in the ultraviolets with a wavelength less than 380 nm, nor in the violets with a wavelength between 380 nanometers and 450 nanometers, nor in the blues with a wavelength of 450 nanometers to 500 nanometers, nor in the reds with a wavelength of 650 nanometers to 750 nanometers, nor in the infrareds with a wavelength greater than 750 nanometers.

[0098] Advantageously, the light emission spectrum of the lighting device 4 avoids encouraging photosynthesis in plants, in particular because it is located almost outside the absorption spectrum of chlorophyll a and mainly outside the absorption spectrum of chlorophyll b. In addition, the light emission spectrum of the lighting device 4 limits disturbances to animals, in particular insects.

Claims

CLAIMS 1. Lighting device (4) comprising at least three LEDs (7, 8, 9), characterized in that each LED (7, 8, 9) is chosen solely from the group consisting of: - a first LED (7) emitting green light with a nominal wavelength between 513 nanometers and 543 nanometers, - a second LED (8) emitting an amber light with a nominal wavelength between 583 nanometers and 605 nanometers, and - a third LED (9) emitting red-orange light with a nominal wavelength between 610 nanometers and 635 nanometers, the lighting device (4) comprising M first LEDs (7), N second LEDs (8) and P third LEDs (9), with M > 1, N > 1 and P > 1.

2. Lighting device (4) according to claim 1, in which: - all of the first M LEDs (7) have a relative light intensity of between 0.39 and 0.43, - the set of N second LEDs (8) has a relative light intensity of between 0.62 and 0.68, and - the set of P third LEDs (9) has a relative light intensity equal to 1.

0.

3. Lighting device (4) according to claim 2, in which: - all of the first M LEDs (7) have a relative light intensity equal to 0.41, - the set of N second LEDs (8) has a relative light intensity equal to 0.

65.

4. Lighting device (4) according to any one of claims 1 to 3, wherein each of the P third LEDs (9) emits a red-orange light with a nominal wavelength between 620 nanometers and 635 nanometers.

5. Lighting device (4) according to any one of claims 1 to 4, in which each LED (7, 8, 9) has a bandwidth of between 10 nanometers and 70 nanometers.

6. Lighting device (4) according to any one of claims 1 to 5, in which the LEDs (7, 8, 9) are coplanar.

7. Lighting device (4) according to any one of claims 1 to 6, in which P < M < N.

8. Lighting device (4) according to claim 7, wherein M = P and N = 2 x M.

9. Lighting device (4) according to any one of claims 1 to 8, which is configured to emit light at a color temperature between 2200 and 2330 Kelvin.

10. Outdoor lamppost (1), comprising a mast (2) carrying a head (3), the head (3) comprising at least one lighting device (4) according to any one of the claims

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