Visible light communication lighting source

Abstract

The application protects a visible light communication lighting source. The visible light communication lighting source comprises a first light source and a second light source, the first light source and the second light source emit first light and second light respectively, the wavelength ranges of the first light and the second light are both in the visible light range, and the first light and the second light form white light by mixing; the first light source and the second light source are respectively driven by different electric signals, the electric signal for driving the first light source is loaded with a communication modulation signal for optical communication; the luminous flux of the first light source is less than that of the second light source. The visible light communication lighting source combines the use of a small-power communication first light source and a large-power lighting second light source, so that the visible light communication lighting source has the characteristics of large-power lighting and high-speed optical communication.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of visible light communication, in particular to a visible light communication lighting source suitable for high-power lighting conditions. BACKGROUND

[0002] Visible light communication (VLC) refers to a communication mode in which light in the visible light band is used as an information carrier to directly transmit optical signals in the air. The visible light communication technology is green and low-carbon, can achieve nearly zero-energy-consumption communication, and can effectively avoid the weaknesses of radio communication electromagnetic signal leakage and electromagnetic wave influence on precision instruments, and quickly build a secure information space that is resistant to interference and interception.

[0003] At the same time, compared with conventional incandescent lamps, fluorescent lamps and the like, white light LED lamps can support faster on-off switching speed and higher rate data transmission.

[0004] In the prior art, the modulated optical signal is usually transmitted by using the illumination light of a white LED, and the optical signal receiver converts the modulated optical signal into an electrical signal output after receiving the modulated optical signal, thereby completing optical communication. Specifically, the white light is mixed by LED blue light and yellow fluorescence emitted by excited fluorescent material. Since the emitted fluorescence has a residual halo problem and cannot realize high-speed optical communication, a filter is usually added in front of the optical signal receiver to filter out the fluorescence spectrum and only accept the remaining LED blue light as signal detection light in order to improve the bandwidth.

[0005] However, as the required power of the illumination increases, the junction capacitance of the LED chip will also increase, and high-speed electrical signals cannot be loaded thereon, so high-speed optical communication cannot be realized, and there is a contradiction between high-power illumination and high-speed optical communication.

[0006] Therefore, it is necessary to provide a visible light communication lighting source that can still realize high-speed optical communication while maintaining high-power illumination. SUMMARY

[0007] In view of the defects of the prior art, the present application provides a visible light communication light source that has both high-power illumination and high-speed optical communication effects.

[0008] The application provides a visible light communication lighting source, which comprises a first light source and a second light source, the first light source and the second light source emit first light and second light respectively, the wavelength ranges of the first light and the second light are both in the visible light range, and the first light and the second light form white light by mixing; the first light source and the second light source are independently driven by receiving electric signals respectively, the electric signal received by the first light source is loaded with a communication modulation signal for optical communication, and the second light source is generally not loaded with the communication modulation signal and is mainly used for lighting; the luminous flux of the first light source is smaller than that of the second light source.

[0009] When the visible light communication lighting source of the application is applied to a visible light communication system, the visible light communication system further comprises a light signal receiver, and a filter is arranged in front of the light signal receiver and used for blocking the second light and transmitting the first light.

[0010] In the technical scheme of the application, the first light and the second light are mixed to form mixed white light for high-power lighting, wherein the corresponding second light source is mainly used for lighting and has a large luminous flux, and for the first light source, the first light source is mainly used for loading a communication signal and adjusting the color temperature of the mixed white light, the luminous flux of the first light source is low and the power is small, and a modulation electric signal of high-speed optical communication can be loaded on the first light source; the two work together, so that the visible light communication lighting source of the application can meet the requirements of high-power lighting and high-speed optical communication at the same time.

[0011] Preferably, the first light emitted by the first light source is blue light with a peak wavelength of 430-480 nm, and the corresponding first light source can be a blue light laser or a blue light LED; compared with ordinary incandescent lamps or fluorescent lamps, the laser and the LED light source can support faster switching speed and meet the requirement of higher-speed optical communication. The wavelength range of the second light emitted by the corresponding second light source covers 480-700 nm, and the second light source can be an LED light source or a light source formed by exciting a fluorescent powder by a blue light LED.

[0012] Preferably, the first light emitted by the first light source is red light with a peak wavelength of 600-700 nm, and the corresponding first light source can be a red light laser or a red light LED light source. The wavelength range of the second light emitted by the corresponding second light source covers 430-700 nm, and the second light source can be a light source formed by exciting a fluorescent powder by a blue light LED.

[0013] Preferably, the second light source is a light source formed by exciting a fluorescent powder layer by a blue light LED, and the fluorescent powder layer is arranged on the light path of the first light emitted by the first light source. The first light emitted by the small-power first light source and the light emitted by the large-power LED chip in the second light source pass through the same fluorescent powder layer and are emitted.

[0014] Preferably, the visible light communication lighting source of the present application comprises a plurality of second light sources arranged in a lattice, and a plurality of first light sources evenly distributed among the plurality of second light sources arranged in the lattice, so that the first light and the second light emitted by the first light sources and the second light sources are uniformly mixed.

[0015] Preferably, the visible light communication lighting source of the present application comprises a plurality of second light sources arranged in a lattice, and a plurality of first light sources evenly distributed among the plurality of second light sources arranged in the lattice, so that the first light and the second light emitted by the first light sources and the second light sources are uniformly mixed.

[0016] Compared with the prior art, the present application has the following advantages: the visible light communication lighting source of the present application comprises a plurality of second light sources arranged in a lattice, and a plurality of first light sources evenly distributed among the plurality of second light sources arranged in the lattice, so that the first light and the second light emitted by the first light sources and the second light sources are uniformly mixed. BRIEF DESCRIPTION OF DRAWINGS

[0017] The accompanying drawings are included to provide a further understanding of the present application, and are incorporated herein and constitute a part of the detailed description. The drawings illustrate embodiments of the present application and, together with the description, serve to explain the principles of the present application.

[0018] Figure 1 FIG. 1 is a schematic diagram of a visible light communication system.

[0019] Figure 2 FIG. 3 is a spectrum combination of white light in an embodiment of the present application.

[0020] Figure 3 FIG. 4 is a spectrum combination of white light in another embodiment of the present application.

[0021] Figure 4a FIG. 5 is a visible light communication lighting source in a ball lamp in an embodiment 1 of the present application. Figure 4b FIG. 6 is a visible light communication lighting source in a panel lamp in an embodiment 2 of the present application.

[0022] Figure 5a FIG. 7 is a visible light communication lighting source in a pointing lighting lamp in an embodiment 3 of the present application. Figure 5b

[0023] Figure 6 DETAILED DESCRIPTION

[0024] The embodiments of the present application will be described in detail below with reference to the accompanying drawings and embodiments.

[0025] ​​Visible light communication combines lighting and communication, gradually popularized LED lamp has faster switching speed, this feature also makes visible light communication rise again; however, as the power required for lighting is getting bigger and bigger, the corresponding junction capacitance of LED chip is getting bigger and bigger, which cannot load high-speed signals and realize high-speed optical communication. How to realize high-speed optical communication under high-power lighting is a very worthy problem.

[0026] The existing LED lighting source is mostly covered with fluorescent powder on the blue LED chip, and the mixed light realizes white light illumination. Among them, because the fluorescent has afterglow problem, it is generally not used as optical signal for light communication; then to improve the bandwidth, a filter is usually added in front of the optical signal receiver to filter out the fluorescent, and finally the remaining blue light (about 10%) of the blue light emitted by the blue LED chip is used as the optical signal for information transmission.

[0027] The present application is just from this feature, the visible light communication light source is creatively divided into two groups, one group can be regarded as a high-power fluorescent light source, which meets the demand of lighting; the other group is a small-power communication light source which can be modulated at high speed, which meets the demand of high-speed optical communication; at the same time, the spectra of the two groups of light sources are different, and the mixed white light is formed.

[0028] As shown in Figure 1 , it is a visible light communication system, which includes the visible light communication lighting light source (as shown in the dashed box) of the present application, the light source includes a first light source and a second light source, the first light source and the second light source are respectively driven by different electrical signals, and then the first light source and the second light source respectively emit first light and second light, the wavelength range of both is in the visible light range (420-700nm).

[0029] The spectra of the first light and the second light are different, and the mixed white light is formed; in particular, the luminous flux of the second light source is much larger than that of the first light source, for example, the luminous flux of the second light source can be set to 5 times that of the first light source.

[0030] For the optical communication part, the first light source with small power is additionally loaded with a modulation signal for communication, and the second light source is generally not loaded with a modulation signal for communication, which is mainly used as a lighting light source; accordingly, a filter is provided in front of the optical signal receiver, the filter transmits the first light emitted by the first light source with communication information, and absorbs or reflects the second light emitted by the second light source, the optical signal receiver receives the modulated optical signal and converts it into an electrical signal output, completing the optical communication. In some embodiments of the present application, the second light source can also be loaded with a low-frequency modulation signal as a supplement to the high-frequency communication modulation of the first light source.

[0031] From the above, the first light source is mainly used for loading communication signals and adjusting color temperature to obtain white light, and its luminous flux is low. The first light source usually adopts LED light source or LD light source, and high-speed optical communication is realized by using the switching characteristics of the light source.

[0032] The combination of the two light sources will be further described below.

[0033] As shown in Figure 2 the spectrum of the white light after the first light and the second light emitted by the first light source and the second light source are combined. The first light is blue light with a peak wavelength between 430-480 nm, and the corresponding first light source can be a laser light source or an LED light source. The wavelength range of the second light covers 480-700 nm, and the corresponding second light source can be an LED light source or a light source formed by a blue LED exciting fluorescent powder.

[0034] Another case is shown in Figure 3 , in which the first light is red light with a peak wavelength between 600-700 nm, and the corresponding first light source can be a laser light source or an LED light source. The wavelength range of the second light covers 430-700 nm, and the corresponding second light source can be a light source formed by a blue LED exciting fluorescent powder. In traditional LED lighting, there is usually only a blue LED exciting yellow fluorescent powder YAG to form a white light, but it lacks red light components in the white light and has poor color rendering index. The present application additionally increases a first light source that emits red light, which can improve the color rendering index of the white light while realizing high-frequency optical communication.

[0035] In this combination, a red light filter is preferably added to the second light source to reduce noise of the optical signal receiver. It can be understood that other wavelengths of light can also be selected for the first light, such as green light, and the corresponding first light source is selected as a green LED light source or an LD light source.

[0036] The present application will be further described in detail below in conjunction with specific embodiments. The following embodiments are only for further description of the present application and should not be understood as limiting the present application.

[0037] Example 1

[0038] Application of the visible light communication lighting source of the present application in general lighting occasions (such as bulb or ceiling lamp, etc.):

[0039] As shown in Figure 4a , the bulb shown includes a lamp panel and an arc-shaped lampshade connected to the lamp panel, and the visible light communication lighting source of the present application is arranged on the lamp panel. Figure 4aThe visible light communication lighting source is composed of a first light source and a second light source, and the first light source and the second light source are respectively driven by different electrical signals. The first light source is a small-power blue light LED chip, and the second light source is a large-power lighting LED. It can be understood that the number of the first light source and the second light source is not limited to this, for example, two or more first and second light sources can also be combined to form the visible light communication lighting source of the present application.

[0040] The first light source is a small-power blue light LED chip, and a high-speed communication signal is further loaded in the driving electrical signal of the first light source to realize high-speed optical communication. The peak wavelength of the first light emitted by the first light source is between 430-480 nm. The second light source is a large-power LED, and no communication signal is loaded. The specific composition of the second light source is that a fluorescent powder is covered on a large-power blue light LED chip, and the wavelength range of the second light emitted by the second light source covers 430-700 nm, and the color temperature is lower than 4500 K. In addition, the small-power LED chip of the first light source can also be arranged in the same LED as the large-power LED chip of the second light source, and a fluorescent powder layer is arranged above the two chips. The two chips are driven by two electrical signals respectively, and the two chips emit blue light, and then the two beams of blue light irradiate on the fluorescent powder layer. The fluorescent powder layer does not contain fluorescent powder at the path corresponding to the blue light emitted by the first light source, and the blue light emitted by the small-power LED chip of the first light source directly transmits through the fluorescent powder layer and is emitted.

[0041] As a comparison, in the prior art technology of optical communication using only a single light source LED lamp: in order to meet the requirement of large-power lighting, similar to the arrangement of the above-mentioned embodiment 1, the LED chip of the single light source arranged on the lamp panel needs to have a large enough area. However, the large-area LED chip will cause the junction capacitance to be larger and larger, and the problem of not being able to respond to the loaded high-speed electrical signal in time occurs, and high-speed optical communication cannot be realized.

[0042] In the present embodiment, in addition to the LED light source for large-power lighting, a small-power and small-area LED light source is added, and the two light sources are driven by different electrical signals. After the first light and the second light are combined, the first light source realizes large-power lighting, and the optical communication information contained in the first light realizes high-speed optical communication.

[0043] In order to reduce the intensity of blue light with the same wavelength as the communication signal and improve the signal-to-noise ratio of the optical signal receiver, a blue light filter can be further added on the second light source.

[0044] The light of the two light sources is further scattered after reaching the lampshade, and the emitted light reaches the optical signal receiver after passing through the optical filter, and the optical communication is completed.

[0045] As a variant of the embodiment 1, the low-power blue light source used for optical communication is a blue laser, as shown in Figure 4b Due to the non-Lambertian distribution of the divergence angle of the laser, in order to mix the light emitted by the high-power illumination LED uniformly, a scattering layer is added on the laser, so that the divergence angle of the blue laser beam is larger; the scattering layer can be silica gel plus titanium oxide scattering particles, or a scattering film, which is not limited here. Further, the laser of the first light source and the blue light emitted by the high-power LED chip in the second light source pass through the phosphor layer provided on the LED chip of the second light source, and the phosphor layer does not contain phosphor at the path corresponding to the laser emitted by the first light source, but contains scattering particles that will scatter the laser that is transmitted. In addition, for the first light source being red or green light, and the second light source being a blue LED chip exciting the phosphor layer to form a light source, the same can also be set so that the light emitted by the LED chips in the first light source and the second light source passes through the same phosphor layer.

[0046] Embodiment 2

[0047] Application of the visible light communication lighting source of the present application in general lighting occasions (panel light or strip light, etc.):

[0048] As shown in Figure 5a , only the case where the visible light communication lighting source of the present application is provided on a large-area lamp panel is shown. It should be noted that the area of the panel light or strip light is relatively large, and the distance from the LED chip as the light source to the lampshade is relatively short, so that the light at the lampshade is relatively uniform, and therefore the lighting source uses a plurality of LED dot matrix arrangements.

[0049] In this embodiment 2, the second light source is a plurality of LED dot matrix arrangements, and in order to make the communication light and the illumination light reach the lampshade uniformly, the first light source also needs to be arranged in a dot matrix arrangement, and the first light source can be an LED light source. The specific distribution is to arrange one first light source beside each of the second light sources, and the plurality of first light sources are in a series connection or a series connection followed by a parallel connection. It is easy to understand that one first light source can also be arranged beside every two or more second light sources, which is not limited here. The plurality of first light sources and the plurality of second light sources are respectively driven by two electrical signals, and the wavelength range combination of the first light and the second light emitted by the first light source and the second light source can be the same as that of the embodiment 1, or can be different, which is not described here.

[0050] As a variant of the embodiment 2, as shown in Figure 5bAs shown, the light emitted by the first light source can also use the method of scattering light guide bar to make the light reaching the lampshade uniform. The specific setting is that the light emitted by the first light source is coupled into the scattering light guide bar first, the scattering light guide bar is folded and arranged beside the second light source arranged in a dot matrix, and the scattering light guide bar has scattered light, for example, the scattering light guide bar can be a scattering optical fiber or a common light guide optical fiber with a light leakage groove cut as a scattering light guide bar, and can also be a square plastic scattering light guide bar. In this way, the first light emitted by the first light source is transmitted and scattered in the scattering light guide bar, and finally mixed uniformly with the second light emitted by the second light source at the lampshade.

[0051] Embodiment 3

[0052] Application of the visible light communication lighting source of the application to the downlight (flashlight, car light, spotlight, etc.):

[0053] As shown in Figure 6 , the visible light communication lighting source in the downlight comprises a combination of a high-power second light source and a low-power first light source, the first light source and the second light source are respectively driven by two electrical signals; and further comprising an optical element for collecting light. The optical element changes the Lambertian divergent light emitted by the visible light communication lighting source into a light beam with a small angle (0-60 degrees) so as to make the light beam irradiate to a specified position or a farther distance.

[0054] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the difference from other embodiments, and the same or similar parts between various embodiments can be referred to each other.

[0055] The above is only the embodiment of the application, and does not limit the patent scope of the application, and any equivalent structure or equivalent process transformation using the content of the specification and the drawings, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the application.

Claims

1. A visible light communication lighting source, characterized in that, include: A first light source and a second light source, the first light source and the second light source respectively emitting first light and second light, the wavelength range of the first light and the second light is both in the visible light range, the first light and the second light are mixed to form white light; the first light source and the second light source are driven by different electrical signals, the electrical signal driving the first light source is loaded with a communication modulation signal for optical communication; the luminous flux of the first light source is less than the luminous flux of the second light source. The luminous flux of a second light source is five times that of a first light source.

2. The visible light communication lighting source according to claim 1, characterized in that, The first light source is an LED light source or a laser light source.

3. The visible light communication lighting source according to claim 1, characterized in that, The first light source is a laser light source, and a scattering layer is provided in the path of the first light emitted from the first light source.

4. A visible light communication lighting source according to any one of claims 1-3, characterized in that, The first light is blue light with a peak wavelength between 430-480nm, and the second light has a wavelength range covering 480-700nm.

5. A visible light communication lighting source according to claim 4, characterized in that, The second light source is an LED light source, or the second light source is a light source formed by blue LEDs exciting phosphors.

6. A visible light communication lighting source according to any one of claims 1-3, characterized in that, The first light is red light with a peak wavelength between 600-700nm, and the second light has a wavelength range covering 430-700nm.

7. A visible light communication illumination source according to claim 1 or 2, characterized in that, The second light source is a light source that excites a phosphor layer formed by a blue LED, and the phosphor layer is disposed in the optical path of the first light emitted by the first light source.

8. A visible light communication lighting source according to claim 1, characterized in that, There are multiple second light sources, which are arranged in a dot matrix pattern, and several first light sources are distributed among the multiple second light sources arranged in a dot matrix pattern.

9. A visible light communication lighting source according to claim 1, characterized in that, There are multiple second light sources, and the multiple second light sources are arranged in a dot matrix pattern; It also includes a scattering light guide strip, which is arranged around the plurality of second light sources; the light emitted by the first light source is coupled into the scattering light guide strip, and the light is transmitted and scattered within the scattering light guide strip.

10. A visible light communication system, characterized in that, include: The visible light communication illumination source according to any one of claims 1-9, An optical signal receiver, wherein a filter is disposed on the optical signal receiver, the filter blocking at least part of the second light while transmitting the first light.

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