RU2692648C2 - Lamp - Google Patents

Abstract

FIELD: lighting.SUBSTANCE: invention relates to lighting devices providing illumination with light simulating a spectrum of sunlight by using light emitting diodes. Lamp contains a set of known LEDs with different emission spectra lying in the frequency range of the order of 400–800 nm, supplied with power drivers. Lamp used LEDs, the peaks of the emission spectra of which are in the frequency range 483–654 nm. Spectra of the LEDs used overlap in different spectral regions of the range, preferably at a level of 0.4–0.8 of the maximum amplitude at the centre frequency of the radiation. In this case, four types of light emitting diodes of different spectrum with a power from 0.1 to 200 W are used, and the emitted spectrum includes the emission spectra of such LEDs as Blue-Green, Green, Warm White and Red Light, with a possible deviation from the centre frequency at ±20 nm. Drivers of these LEDs are made with the possibility of supplying the power supply of such a magnitude that the level of luminous flux from the corresponding LEDs is equal to 1.52; 1.34; 1.69 from the level of the luminous flux emitted by the Red Light LED, with the possible deviation of the indicated energy values by ±25 %, or each type of spectrum is formed by a set of similar LEDs emitting light of the same frequency, with the ability to generate the power of the light flux, the same for each type of spectrum. Besides these LEDs have a maximum emission at frequencies of 490, 524, 587 and 634 nm, respectively, with a possible deviation from the centre frequency at ±20 nm.EFFECT: technical result consists in providing the luminaire with a radiation spectrum close to that of sunlight in the simulated frequency range, while minimizing the total number of LEDs used.1 cl, 3 tbl, 5 dwg

Description

The invention relates to lighting devices that provide illumination with light simulating the spectrum of sunlight through the use of light-emitting diodes.

A lamp is known that contains a set of LEDs with different emission spectra, supplied with drivers. In this case, the lamp contains twelve red LEDs with a wavelength of 660 nm, six orange LEDs with a wavelength of 612 nm and one blue LED with a wavelength of 470 nm (US 6921182, class A61B 1/32, 2005).

Also known luminaire containing a set of known LEDs with different emission spectra, lying in the range of about 400-800 nm, equipped with drivers (RU # 2504143, class A01G 7/04, A01G 9/24. Bull. No. 2. 2014). The luminaire uses at least two types of LEDs, and it is preferable that the first type LEDs emit in the blue with a wavelength of 400 nm to 500 nm, and the second type LEDs emit in the red with a wavelength of 600 nm up to 700 nm, moreover, the light emitted by the first group of LEDs consists of approximately 80% -90% red light and 10% -20% blue light.

All of these solutions were aimed at obtaining the optimal combination of wavelengths to enhance the growth rate of plants, as well as reducing energy consumption and increasing the service life of luminaires, while their technical implementation is compared with existing light-growth technologies. However, these solutions do not provide a radiation spectrum close to that of the sun to which the plants are genetically adapted. In addition, the combination of wavelengths chosen to enhance plant growth in existing technical solutions is unattractive for people observing an illuminated plant, and sometimes even harmful to the eyes.

The problem to which the invention is directed is to provide the radiation spectrum in the luminaire corresponding to the spectrum of sunlight in the modeled frequency range.

The technical result is to provide for the lamp emission spectrum close to the emission spectrum of sunlight in the simulated frequency range, while minimizing the total number of LEDs used.

The task is solved by the fact that the lamp containing a set of known LEDs with different emission spectra lying in the frequency range of the order of 400 - 800 nm, equipped with power drivers, is supplemented with the following: light-emitting diodes are used, the emission spectra peaks of which are in the frequency range 483-654 nm, at the same time, the spectra of the used LEDs overlap each other in different spectral regions of the range, preferably, at a level of 0.4-0.8 of the maximum amplitude at the center frequency of the radiation, and four e type of light emitting diodes of different spectrum with a power from 0.1 to 200 W, and the emitted spectrum includes the emission spectra of such LEDs as Blue-Green, Green, Warm White and Red Light, with a possible deviation of ± 20 nm from the center frequency, while the drivers of these LEDs are made with the possibility of supplying energy of such a magnitude that the level of luminous flux from the corresponding LEDs is equal to 1.52; 1.34; 1.69 from the level of the luminous flux emitted by the Red Light LED, with a possible deviation of the indicated values by ± 25%. In addition, each type of spectrum is formed by a set of LEDs of the same type, emitting light of the same frequency, with the ability to generate the power of the luminous flux of the same for each type of spectrum. These LEDs have a maximum emission, at frequencies

respectively, 490, 523, 587 and 634 nm with a possible deviation from the center frequency by ± 20 nm.

Comparative analysis of the signs of the claimed solution with the signs of the prototype and analogs indicates the compliance of the stated solution to the criterion of "novelty."

The set of features of the distinctive part of the formula of the invention provides the lamp with a radiation spectrum corresponding to sunlight in the frequency range 483-654 nm, and the distinctive features of the distinctive part of the formula of the invention provide a solution to the following set of functional tasks:

The signs “LEDs are used, whose emission spectra are in the range of 483-654 nm”, provide the most complete approximation to the spectrum of sunlight in the specified range, with the minimum number of used types of LEDs.

The signs "the spectra of the used LEDs overlap each other in different spectral parts of the range" contribute to the alignment (reduction of waviness) of the total spectrum of the lamp.

Signs indicating that the spectra constituting a set of LEDs overlap "preferably at a level of 0.4-0.8 of the maximum amplitude at the center frequency of the radiation of the corresponding LEDs" also help to reduce the waviness of the total spectrum of the lamp.

Signs indicating that “four types of light-emitting diodes of a different spectrum with a power from 0.1 to 200 W are used, and the emitted spectrum includes emission spectra of such LEDs as Blue-Green, Green, Warm White and Red Light” ensure that the lamp forms a radiation spectrum close to solar light in a given frequency range.

Signs indicating that the spectrum emitted by the LEDs “may deviate from the center frequency by ± 20 nm” may set the parameters that ensure the arrangement of the LED bar or array.

Signs indicating that “the drivers of these LEDs are made with the possibility of supplying the power supply of such a value that the level of luminous flux from the corresponding LEDs is equal to 1.52; 1.34; 1.69 from the level of the luminous flux emitted by the Red Light LED ”provides the necessary equalization of the radiation emitted by the LEDs, reducing the waviness of the total spectrum of the lamp.

Signs indicating that the level of energy supplied to the LEDs by ± 25% is possible to deviate, set the parameters for supplying energy to the LEDs, which ensure an optimal layout of the LED bar or array.

Signs indicating that “each type of spectrum is formed by a set of LEDs of the same type, with the ability to generate luminous flux power of the same for each type of spectrum” provide the ability to use both a single high-power LED and a matrix formed from several low-power LEDs giving a total radiation power required for the formation of a given level of luminous flux.

Signs indicating that “the named LEDs have a maximum emission, at frequencies, respectively, 490; 523; 587 and 634 nm specify the technical characteristics of the LEDs.

The essence of the invention is illustrated by drawings, where

in fig. 1 shows the emission spectra of the four types of LEDs used, aligned with the radiation power;

in fig. 2 shows the total emission spectrum of four types of LEDs that mimic the solar spectrum in the frequency range 483-654 nm (pink curve "Lamp Spectrum" - the spectrum of the lamp of four LEDs; the red curve "Spectrum of the Sun" - the spectrum of the sun, measured in Vladivostok 22.05.2017 g at 11:36 with a TKA spectrophotometer; dashed pink curve — Red LED spectrum; dashed gray curve — Warm White LED spectrum; dashed green curve — Green LED spectrum; dashed blue curve — Blue-green spectrum w);

in fig. 3 shows an LED array consisting of four LEDs with different types of spectra, forming a total emission spectrum simulating the solar spectrum in the frequency range 483-654 nm;

in fig. 4 shows the actual spectral and energy parameters of the four types of LEDs, which allowed to form the radiation of the lamp close to the solar spectrum in a given range;

in fig. 5 shows the real total emission spectrum of a matrix of four LEDs with the level of luminous flux from the Blue-Green, Green and Warm White LEDs equal to 1.52; 1.34; 1.69 from the level of the luminous flux emitted by the Red LED.

Currently, the industry produces various LEDs with a narrow and wide emission band, with a radiation peak falling on one or several specific frequencies of light. A wide range of light frequencies from UV to red and infrared light is covered. In addition, there are white light LEDs with different color temperatures.

Thus, if there is a set of LEDs with different spectra (Fig. 1), then one can type a ruler or a matrix of LEDs with overlapping spectral curves at a level of about 0.4-0.8 and then, summing up their energy parameters, they will form radiation spectrum corresponding to sunlight in a given frequency range (Fig. 2). Thus, if the simulated range of the spectrum of solar radiation is known, then selecting different LEDs with a different spectrum and setting them different radiation intensity, you can get a light source very similar in its spectrum to solar radiation. The difficulty lies in the fact that individual monochrome LEDs have a very narrow spectrum of radiation generation of a certain frequency and a non-constant level of radiation power with the same product ratings from different manufacturers and even within the same batch, from the same manufacturer. Therefore, to cover the entire frequency range of photosynthetically active radiation of the solar spectrum (from 400 to 800 nm) a large number of different types of LEDs are required. However, the greater the number of LEDs used, the more difficult it is to select their exact parameters, which include power, radiation frequency and current supply modes, so that the synthesized frequency band exactly matches the solar spectrum. The necessary condition for the overlap of the spectral curves at a level of approximately 0.4-0.8 causes a strong influence of individual spectra on each other. A change in the radiation power of just one of the LEDs, for example, Red, causes a change in the level of the emission peaks of all the other LEDs, first and foremost the maximum effect will be on the Warm White LED and less effect on the Green and Blue-Green LEDs. Subsequent adjustment of the radiation level of the Warm White LED will change the level of the peaks of the radiation and the Red, Green and Blue-green LEDs. Sequential iteration of all possible values of the radiation levels of each LED to approach the solar spectrum can take a very long time.

For each type of LEDs, spectral and energy parameters were taken with a TKA-Spectrum spectrophotometer (Fig. 1, Fig. 2 and Fig. 4), which allowed the luminaire to form close to the solar spectrum (Fig. 2, Fig. 4).

The simulated range of 483–654 nm from the photosynthetically active radiation range of the solar spectrum, in the general case of 400–800 nm, is realized by a set of four types of LEDs with different power and different spectra. For example, in this set there are three 50 W LEDs of the following composition: Green, Warm White, Red and 10 W Blue-Green (Fig. 3). FIG. 4 shows the emission spectra of each LED. It is seen that the maximum values of the radiation power density measured by the TKA-Spectrum spectrophotometer at a distance of 50 cm from the center of the LEDs, along their axis, have different amplitudes of radiation peaks and different locations on the frequency axis. In this case, the same 1500 mA current was applied to all 50 W LEDs, and 870 mA to Blue-Green (Table 1). The parameters of the LEDs and their emissivity are chosen in such a way that the radiation powers of their spectra correspond to the parameters of the power coefficients of the radiation of the LEDs given in Table 3. In this case, if we simply sum up the powers of all the emission spectra of these LEDs, then the total spectrum will have a shape very close to the spectrum sunlight in a given frequency range (in Fig. 5, the “Luminaire” curve is pink in color; the simulated frequency range is highlighted with a yellow background). But it often happens that the LEDs have other radiation powers and, if they are simply summed, the resulting curve will be very far from the shape of sunlight. In this case, in order to obtain the spectrum of the sun from this set of LEDs in the frequency range 483-654 nm, it is necessary to reduce all radiation peaks to the same value, i.e. normalize. There are two ways to do this: the first is to adjust it by changing the supply current with the help of the current supply drivers for each LED; the second - adjustment is carried out by selecting the number of LEDs of the same frequency, which operate in the nominal operating mode, but which have different radiation powers, i.e. different passport power rating. Selecting the number of LEDs of the same frequency, emitting LEDs, achieve the required total radiation power. After bringing the radiation level of all types of LEDs to the same value, the emission spectrum of all LEDs will take the form shown in FIG. 1. At the same time, the mentioned areas of the emission spectra of the LEDs overlap each other in different spectral regions of the simulated emission range, somewhere, at a level of 0.4–0.8 of the maximum amplitude. A warm white LED has two peaks of radiation: at a frequency of 440 nm of a smaller size and at a frequency of 587 nm, the maximum radiation.

The yellow background in FIG. 2 highlighted the area of modeling the solar spectrum in the frequency range 483-654 nm. Table 2 shows the parameters of four types of LEDs (or sets of LEDs of the same type) simulating the range of the 483-654 nm solar spectrum after they are reduced to the same radiation density and standardization.

From Table 2 it can be seen that the Warm White LED has two spectral peaks of the radiation power, one of which is at a frequency of 587 nm (the maximum amplitude is 1), and at a frequency of 440 nm it is 0.67. All other LEDs have one peak of radiation. The measurements were carried out with a TKA-Spectr spectrophotometer, at a distance of 500 mm from the center of the LEDs along their axis.

If each LED emits light energy measured in W / m ² , in the proportions corresponding to the coefficients given in Table 3, then the total power spectrum of the luminaire radiation shown in FIG. 2. (curve Spectrum of the Lamp), which coincides with the power spectrum of the solar radiation in this range.

In this case, all LEDs should receive energy from the current power drivers in such a way that their radiation corresponds to the coefficients of table 3. As a result, the total radiation spectrum of the lamp will be almost the same as the radiation spectrum of sunlight (Fig. 2, the pink color of the curve). The power spectrum of sunlight was measured with a TKA-Spectr brand spectrophotometer in Vladivostok on 05.22.2017 at 11-36 local time.

In the process, an active LED matrix was formed (Fig. 3), in which each LED was powered by a current using a current driver so that the radiation power of each type of LED, measured 50 cm from the LEDs, contributed to the total radiation in accordance with the modes shown in Table 3. The spectra of each type of LED, measured with a spectrophotometer, are shown in FIG. four.

When all the LEDs with the above modes were turned on, the radiation power spectrum of the luminaire was characterized by the dependence shown in FIG. 5 (curve "Lamp" pink color; curve of red color - the spectrum of the sun; yellow background shows the simulated range). The obtained spectral irradiance in the frequency range 483-654 nm is equal to 97.5 mW / m at a distance of 50 cm from the luminaire and has a smooth character, almost completely corresponds to the solar spectrum with a root-mean-square deviation error not exceeding 6.5%.

It is important to note that the coefficients in Table 3 refer to the power density of the light emitted, or to the spectral irradiance measured at the same distance by the same device in this case with a TKA-Spectr spectrophotometer. In this case, the coefficients in Table 3 do not characterize the energy consumed by the LEDs or the amount of current flowing through the LEDs. This is due to the fact that K.P.D. Each LED is different and the power modes of the LEDs are also all different. For example, if there are two LEDs of the same type, but with different KPD, for example, 15% and 30%, then the spectral irradiance obtained at the same distance from the first LED will be 2 times less with the same power supply current or power consumption than the second. And if they are powered by current in accordance with Table 3, then the total spectrum of all LEDs will differ greatly from the calculated spectrum shown in FIG. 2. If there are two LEDs with the same radiation frequency but different power ratings, for example, 1 W and 10 W, then the first type of LED can be powered with a maximum current of 300 mA, and the second type - 900 mA. Accordingly, the power density of the radiation of light energy they will be very different. Therefore, the coefficients given in Table 3 should characterize only the ratio of irradiance values for each type of LED, measured with a spectrophotometer at the same distance from the LED.

In addition, it is very important to use such power modes for all four types of LEDs or groups of radiation types of LEDs of the same type in the assembly, so that each group of LEDs of the same type emitting light of the same frequency gives a total peak of radiation of the same size, which is convenient to equate to a relative unit, as shown in FIG. one.

Claims (1)

A luminaire containing a set of known LEDs with different emission spectra lying in the frequency range of the order of 400-800 nm, supplied with power drivers, characterized in that the LEDs used, the peaks of the emission spectra of which are in the frequency range 483-654 nm, while the spectra of the LEDs used overlap each other in different spectral regions of the range, preferably at a level of 0.4-0.8 of the maximum amplitude at the center frequency of radiation, and four types of LEDs of different spectrum are used; awn from 0.1 to 200 W, and the emitted spectrum includes the emission spectra of LEDs such as Blue-Green, Green, Warm White, and Red Light, with a possible ± 20 nm deviation from the center frequency, while the drivers of these LEDs are designed to energizing the power supply of such a value so that the luminous flux from the corresponding LEDs is equal to 1.52 1.34; 1.69 from the level of the luminous flux emitted by the LED Red light, with a possible deviation of the indicated energy values by ± 25%, or each type of spectrum is formed by a set of LEDs of the same type emitting light of the same frequency, with the ability to generate luminous flux the same for of each individual type of spectrum, moreover, these LEDs have a maximum emission at frequencies of 490, 524, 587 and 634 nm, respectively, with a possible deviation from the center frequency of ± 20 nm.

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