White light emitting crystal grain and lighting device
By using multiple fluorescent layers and blue light emitting diode elements of different wavelengths in the white light emitting grains, combined with the brightness adjustment of the control unit, the problem that white light emitting grains in the prior art is difficult to simulate sunlight, and the effect of high color reduction and color temperature approaching sunlight is achieved.
Patent Information
- Application Number
- CN202421321818.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Priority Date
- 2024-04-25
- Filing Date
- 2024-06-11
- Publication Date
- 2025-05-06
- Estimated Expiration
- 2034-06-11
AI Technical Summary
The existing white light luminescent grains are difficult to simulate sunlight, and there is a significant drop in the color temperature of the light emitted by the lighting device compared to the real sunlight.
The white light emitting grains containing three fluorescent layers are used to emit blue light of different wavelengths through the first, second and third light emitting diode elements, and the fluorescent layer generates white light, and the brightness of the white light emitting grain is adjusted through the control unit to approximate the color temperature of the black body radiation.
The white light emitted by the white light emitting grains has a blue-green light component, which simulates the effect of sunlight, and adjusts the brightness to make the light source of the lighting device approximate the sunlight at different color temperatures, improving the color reduction degree.
Smart Images
Figure CN222840041U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a luminous crystal grain and a lighting device, in particular to a white light luminous crystal grain capable of emitting white light and a lighting device with adjustable color temperature. Background Art
[0002] See also Figure 1 , is the spectrum of white light emitted by a general white light emitting crystal particle. The definition of white light is that its spectrum is continuous, and its spectrum range is 380nm to 780nm, and its luminous hue can change from reddish, yellowish to bluish with the color temperature. Since the white light emitted by a general white light emitting crystal particle lacks blue-green light (see Figure 1 The color rendering index R9 and R12 usually do not exceed 90, and cannot completely simulate sunlight. Therefore, how to make the white light emitted by ordinary white light emitting crystal particles simulate real sunlight is the focus of current white light emitting crystal particle developers.
[0003] See also Figure 2 In general, lighting devices are usually equipped with two groups of light-emitting crystals with different color temperatures and adjustable brightness. Figure 2 The coordinates in the CIE chromaticity diagram shown are defined as a low color temperature coordinate 110; the other one of the luminescent crystal particles with a higher color temperature is Figure 2 The coordinates in the CIE chromaticity diagram shown are defined as a high color temperature coordinate 120. The light emitted by each of the light-emitting crystals is mixed to form the light emitted by the lighting device. By adjusting the brightness of the light-emitting crystals respectively, the color temperature of the mixed light source (i.e., the light emitted by the lighting device) can be changed within the connecting line between the low color temperature coordinate 110 and the high color temperature coordinate 120. However, the connecting line between the low color temperature coordinate 110 and the high color temperature coordinate 120 is still the same as the connecting line between the low color temperature coordinate 110 and the high color temperature coordinate 120. Figure 2 In other words, the color temperature of the light emitted by a general lighting device is still significantly different from the color temperature of the real sunlight. Utility Model Content
[0004] The purpose of the utility model is to provide a white light emitting crystal particle which can solve at least one of the above problems.
[0005] The utility model white light emitting crystal grain comprises a base plate, a first light emitting diode element, a second light emitting diode element, a third light emitting diode element and three fluorescent layers. The first light emitting diode element is arranged on the base plate and can emit a first blue light with a wavelength between 410nm and 450nm. The second light emitting diode element is arranged on the base plate and can emit a second blue light with a wavelength between 450nm and 470nm. The third light emitting diode element is arranged on the base plate and can emit a third blue light with a wavelength between 460nm and 490nm. The fluorescent layers cover the surfaces of the first light emitting diode element, the second light emitting diode element and the third light emitting diode element respectively. When the fluorescent layers are irradiated by the first blue light, the second blue light and the third blue light respectively, the fluorescent layers are excited to make the white light emitting crystal grain generate white light.
[0006] According to the white light emitting crystal grain of the present invention, the first blue light emitted by the first light emitting diode element has a color temperature between 2700K and 7500K, the second blue light emitted by the second light emitting diode element has a color temperature between 2700K and 7500K, and the third blue light emitted by the third light emitting diode element has a color temperature between 2700K and 7500K.
[0007] The white light luminescent crystal grain of the utility model has a color rendering index R9 greater than 91 when the ambient temperature is between 30° C. and 90° C.
[0008] The white light luminescent crystal grain of the utility model has a color rendering index R12 greater than 91 when the ambient temperature is between 30° C. and 90° C.
[0009] Another object of the utility model is to provide a lighting device that can provide a basic light source close to black body radiation.
[0010] The lighting device of the utility model comprises a light source unit and a control unit. The light source unit comprises at least three of the aforementioned white light emitting crystal grains. The color coordinates corresponding to the white light generated by the white light emitting crystal grains in the CIE chromaticity diagram are respectively defined as a first coordinate, a second coordinate and a third coordinate. The correlated color temperatures of the first coordinate, the second coordinate and the third coordinate are different from each other. The connecting lines of the first coordinate, the second coordinate and the third coordinate form two intersections with the black body radiation line. The connecting lines of the first coordinate, the second coordinate and the third coordinate surround and define a dimming area. The dimming area includes part of the black body radiation line, and the corresponding color coordinates of the light source after the light source unit is mixed in the CIE chromaticity diagram are defined as mixed light coordinates. The control unit is electrically connected to the light source unit, and is used to output currents to the white light emitting crystal grains respectively to control their brightness changes respectively, so that the mixed light coordinates move in the dimming area.
[0011] In the lighting device of the present invention, at least two of the first coordinate, the second coordinate and the third coordinate are not located on the black body radiation line.
[0012] In the lighting device of the present invention, the first coordinate, the second coordinate and the third coordinate are not located on the black body radiation line.
[0013] In the lighting device of the present invention, the connecting line of the first coordinate, the second coordinate and the third coordinate forms two intersections with the black body radiation line, the color temperature of one of the intersections is not higher than 1800K, and the color temperature of the other intersection is not lower than 10000K.
[0014] In the lighting device of the present invention, the connecting line of the first coordinate and the third coordinate forms two intersections with the black body radiation line, the color temperature of one of the intersections is not higher than 1800K, and the color temperature of the other intersection is not lower than 10000K.
[0015] In the lighting device of the present invention, the correlated color temperature of the first coordinate is between 1800 and 2600K.
[0016] In the lighting device of the present invention, the correlated color temperature of the second coordinate is between 2600 and 4500K.
[0017] In the lighting device of the present invention, the correlated color temperature of the third coordinate is between 6500 and 10000K.
[0018] The lighting device of the utility model further comprises a substrate, and the white light emitting crystal grains are arranged in a staggered manner on the substrate.
[0019] In the lighting device of the utility model, the light source unit further comprises a red light group, a green light group and a blue light group electrically connected to the control unit and used to emit monochromatic light. The red light group, the green light group and the blue light group respectively receive the current output by the control unit to change their brightness.
[0020] In the lighting device of the utility model, the corresponding color coordinates of the red light group, the green light group and the blue light group in the CIE chromaticity diagram are defined as red light coordinates, green light coordinates and blue light coordinates respectively. The connecting lines of the red light coordinates, the green light coordinates and the blue light coordinates surround and define a light mixing area, and the area of the light mixing area is larger than the area of the dimming area.
[0021] The beneficial effect of the utility model is that the first light emitting diode element, the second light emitting diode element and the third light emitting diode element emit three kinds of blue light with wavelengths between 410nm and 450nm, between 450nm and 470nm and between 460nm and 490nm, so that the mixed light after the fluorescent layer is excited is
[0022] In addition, the dimming area of the white light generated by the white light emitting crystal grain in the CIE chromaticity diagram includes part of the black body radiation line, so that the mixed light coordinates corresponding to the light source unit after mixing light can be close to the black body radiation line as the brightness of the white light emitting crystal grain changes, so as to achieve the effect that the light emitted by the lighting device is similar to sunlight at different color temperatures. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Figure 1 It is a spectrum diagram, which illustrates the relative intensity variation of white light emitted by a general white light emitting crystal grain at different wavelengths;
[0024] Figure 2 It is the CIE chromaticity diagram, which shows the color coordinates corresponding to the two groups of light-emitting crystals in a general lighting device;
[0025] Figure 3 is a schematic block diagram illustrating an embodiment of the lighting device of the utility model;
[0026] Figure 4 is a schematic diagram illustrating the connection relationship between a plurality of white light emitting chips and a base plate of the embodiment;
[0027] Figure 5 is a schematic diagram illustrating the connection relationship between a base plate, a first light emitting diode component, a second light emitting diode component, a third light emitting diode component and three fluorescent layers of any of the white light emitting crystal particles;
[0028] Figure 6 is a spectrum diagram, illustrating the relative intensity variation of white light emitted by any of the white light emitting crystal particles at different wavelengths;
[0029] Figure 7 A graph showing changes in correlated color temperature of the white light emitting crystal grain and general white light emitting crystal grains at different ambient temperatures;
[0030] Figure 8 A graph showing a change in the color rendering index R9 of the white light emitting crystal grain and a general white light emitting crystal grain at different ambient temperatures;
[0031] Fig. 9 A graph showing changes in the color rendering index R12 of the white light emitting crystal grain and a general white light emitting crystal grain at different ambient temperatures;
[0032] Fig.10 is the CIE chromaticity diagram of the embodiment;
[0033] Fig.11 is a schematic block diagram illustrating another implementation aspect of the embodiment;
[0034] Fig.12 is a CIE chromaticity diagram of another implementation aspect of the embodiment. DETAILED DESCRIPTION
[0035] The utility model is described in detail below with reference to the accompanying drawings and embodiments.
[0036] See also Figure 3 and Figure 4 , is an embodiment of the lighting device of the utility model. The lighting device comprises a light source unit 1, a control unit 2 electrically connected to the light source unit 1, and a substrate 3 on which the light source unit 1 is mounted. The lighting device can be any type of lighting device such as a photographic lamp, a ceiling mounted recessed lamp, a table lamp, a plant growth lamp, etc.
[0037] The light source unit 1 includes a first white light group 11, a second white light group 12, and a third white light group 13 that can emit white light and have different correlated color temperatures (CCTs). The first white light group 11, the second white light group 12, and the third white light group 13 each include a plurality of white light emitting crystal grains 10. The white light emitting crystal grains 10 of the first white light group 11, the white light emitting crystal grains 10 of the second white light group 12, and the white light emitting crystal grains 10 of the third white light group 13 are arranged alternately on the substrate 3 and are arranged in a slightly circular shape as a whole. The alternate arrangement of the white light emitting crystal grains 10 of the first white light group 11, the second white light group 12, and the third white light group 13 can make the light source after color mixing uniform, but in other embodiments, the arrangement method and shape of the light source unit 1 are not limited to a specific form. Furthermore, the first white light group 11 , the second white light group 12 , and the third white light group 13 may each include only one white light emitting chip 10 , depending on actual needs.
[0038] See also Figure 5 Each of the white light emitting crystal particles 10 comprises a base plate 101, a first light emitting diode element 102, a second light emitting diode element 103 and a third light emitting diode element 104 disposed on the base plate 101, and three fluorescent layers 105 respectively covering the surfaces of the first light emitting diode element 102, the second light emitting diode element 103 and the third light emitting diode element 104. The first light emitting diode element 102, the second light emitting diode element 103 and the third light emitting diode element 104 are all light emitting diode (Light Emitting Diode, LED for short) package elements. Specifically, the first light emitting diode element 102 can emit a first blue light (not shown) with a wavelength between 410nm (nanometers) and 450nm when a voltage is applied, and the first blue light emitted by the first light emitting diode element 102 has a color temperature between 2700K (Kelvin) and 7500K. The second LED element 103 can be applied with a voltage to emit a second blue light (not shown) with a wavelength between 450nm and 470nm, and the color temperature of the second blue light emitted by the second LED element 103 is between 2700K and 7500K. The third LED element 104 can be applied with a voltage to emit a third blue light (not shown) with a wavelength between 460nm and 490nm, and the color temperature of the third blue light emitted by the third LED element 104 is between 2700K and 7500K.
[0039] The fluorescent layer 105 is, for example, a structure composed of fluorescent powders of different colors, and the components or composition ratios of the fluorescent layer 105 may vary according to the wavelength of blue light emitted by the corresponding light emitting diode element and can be adjusted as required.
[0040] See also Figure 6 When the fluorescent layer 105 is irradiated by the first blue light, the second blue light and the third blue light respectively, the fluorescent layer 105 will be excited to generate light of different colors. The light of different colors generated by the fluorescent layer 105 will be mixed to present white light with blue-green light, so that the white light emitting crystal grain 10 generates white light and simulates sunlight.
[0041] The white light generated by the white light emitting crystal grain 10 has an ultra-high color rendering index (i.e., the quantitative degree of a light source's ability to present the color of a real object, in English: Color Rendering Index, abbreviated as: CRI). Specifically, the color rendering indexes R1 to R15 of the white light generated by the white light emitting crystal grain 10 are greater than 90, and in particular, the color rendering indexes R9 and R12 of the white light generated by the white light emitting crystal grain 10 are both greater than 93 when the correlated color temperature is 5886K, which can improve the color reproduction. In this embodiment, the measured values of the color rendering index Ra, R1 to R15 of the white light emitting crystal grain 10 when the correlated color temperature is 5886K are shown in Table 1 below.
[0042] Table 1
[0043] Ra R1 R2 R3 R4 R5 R6 R7 Measurement value 98 99 99 96 97 99 98 97 R8 R9 R10 R11 R12 R13 R14 R15 Measurement value 97 99 96 98 96 99 97 98
[0044] See also Figure 7 , is the change of the correlated color temperature of the white light emitting crystal grain 10 and a general white light emitting crystal grain at different ambient temperatures (TP). Figure 7 The solid line in the figure shows that the correlated color temperature of a general white light emitting crystal changes in Figure 7 The dotted line in . Figure 7 It is shown in FIG. 1 that the correlated color temperature of the white light emitting chip 10 is less significantly affected by the ambient temperature than that of a common white light emitting chip.
[0045] See also Figure 8 , is the color rendering index R9 change of the white light emitting crystal grain 10 and the general white light emitting crystal grain under different ambient temperatures. The color rendering index R9 change of the white light emitting crystal grain 10 is based on Figure 8 The solid line in the figure shows that the color rendering index R9 of a general white light emitting crystal changes as follows: Figure 8 The dotted line in . Figure 8It is shown in the figure that the color rendering index R9 of the white light emitted by the white light emitting crystal grain 10 is always greater than 91 in different ambient temperatures (30°C to 90°C), and the color rendering index R9 of the white light emitting crystal grain 10 is higher than that of the general white light emitting crystal grain.
[0046] R9 is less affected by ambient temperature.
[0047] See also Fig. 9 , is the color rendering index R12 change of the white light emitting crystal grain 10 and the general white light emitting crystal grain under different ambient temperatures. The color rendering index R12 change of the white light emitting crystal grain 10 is based on Fig. 9 The solid line in the figure shows that the color rendering index R12 of a general white light emitting crystal changes as follows: Fig. 9 The dotted line in . Fig. 9 It is shown in the figure that the color rendering index R12 of the white light emitted by the white light emitting crystal particle 10 is always greater than 91 in different ambient temperatures (30° C. to 90° C.).
[0048] See also Figure 3 , Figure 4 and Fig.10 , the light emitted by the white light emitting crystal grains 10 of the first white light group 11 is mixed and then Fig.10 The corresponding color coordinate in the CIE chromaticity diagram (in this embodiment, CIE 1976) is defined as a first coordinate 112, the corresponding color coordinate in the CIE chromaticity diagram after the light emitted by the white light emitting crystal grains 10 of the second white light group 12 is defined as a second coordinate 122, and the corresponding color coordinate in the CIE chromaticity diagram after the light emitted by the white light emitting crystal grains 10 of the third white light group 13 is defined as a third coordinate 132. The correlated color temperatures of the first coordinate 112, the second coordinate 122, and the third coordinate 132 are different from each other. In this embodiment, the first coordinate 112, the second coordinate 122, and the third coordinate 132 are not located on the black body radiation line 41 for illustration, but in other embodiments, one of the first coordinate 112 and the third coordinate 132 can also be located on the black body radiation line 41, and the effect claimed in this case can still be achieved. The correlated color temperatures of the first white light group 11, the second white light group 12 and the third white light group 13 are respectively between 1800 and 2600K, 2600 and 4500K, and 6500 and 10000K. In the present embodiment, the correlated color temperatures of the first white light group 11, the second white light group 12 and the third white light group 13 are respectively 1800K, 3500K and 10000K.
[0049] The triangular connecting line of the first coordinate 112, the second coordinate 122 and the third coordinate 132 forms two intersection points 18 with the black body radiation line 41. The color temperature of one of the intersection points 18 is not higher than 1800K, and the color temperature of the other intersection point 18 is not lower than 10000K. In this embodiment, the intersection point 18 is located on the connecting line of the first coordinate 112 and the third coordinate 132 for illustration, but the intersection point 18 can also be located on any two sides of the triangular connecting line, and is not limited to this. The triangular connecting line of the first coordinate 112, the second coordinate 122 and the third coordinate 132 surrounds and defines a dimming area 42, and the dimming area 42 includes part of the black body radiation line 41. In other words, the black body radiation line 41 in the dimming area 42 is the predetermined dimming target. The corresponding color coordinate of the light source after the light source unit 1 is mixed in the CIE chromaticity diagram is defined as a mixed light coordinate 17.
[0050] The control unit 2 is, for example, a combination of a microprocessor, a storage device such as a memory, and a current driver, and can output driving currents to the first white light group 11, the second white light group 12, and the third white light group 13 according to an algorithm, so as to control the brightness changes of the white light emitted by the first white light group 11, the second white light group 12, and the third white light group 13, respectively, so that the mixed light coordinate 17 moves in the dimming area 42 according to the brightness changes of the three, so as to mix light sources with different correlated color temperatures ranging from 1800K to 10000K. The algorithm is to calculate the power ratio of the first white light group 11, the second white light group 12 and the third white light group 13 (for example, 35% for the first white light group 11, 63% for the second white light group 12 and 3% for the third white light group 13) corresponding to the predetermined color temperature (for example, 3000K) of the mixed light coordinate 17 in advance according to the spectrum of the first white light group 11, the second white light group 12 and the third white light group 13, and fit the setting values thereof into a function or a table, and then store the function or the table in the control unit 2 for use in the algorithm. The power ratio is, for example, when the light source unit 1 is expected to use 300W of power, then according to the above power ratio, 300W of power is allocated to the first white light group 11, the second white light group 12 and the third white light group 13 for emitting light.
[0051] In this embodiment, in the algorithm, the power ratio of the light mixing coordinate 17 at each color temperature is set as shown in Table 2. As can be seen from Table 2, the D measured by the light mixing coordinate 17 at each color temperature is uvThe values (defined as the distance of the color coordinate from the black body radiation line 41) are all between -0.0005 and 0.0005 except for 9000K, 9500K and 10000K, and the CRI values (color rendering index) are all greater than 95. That is to say, the mixed light coordinate 17 corresponding to the light source mixed out of the present embodiment can fall on the black body radiation line 41 or be close to the black body radiation line 41, and the light source has only a very slight difference from the real sunlight, and can achieve the effect of highly restoring the real color of the object.
[0052] Table 2
[0053]
[0054]
[0055]
[0056] See also Fig.11 , Fig.12 , which is another implementation of this embodiment. In another implementation of this embodiment, the light source unit 1 also includes a red light group 14, a green light group 15 and a blue light group 16 electrically connected to the control unit 2 and used to emit monochromatic light. The red light group 14 includes a plurality of red light emitting diode elements (not shown). The green light group 15 includes a plurality of green light emitting diode elements (not shown). The blue light group 16 includes a plurality of blue light emitting diode elements (not shown). The red light group 14, the green light group 15 and the blue light group 16 respectively receive currents of different sizes output by the control unit 2, so that the brightness of the monochromatic light emitted by the red light group 14, the green light group 15 and the blue light group 16 can be controlled and adjusted. The monochromatic light is defined as having a half-wave width range of 5nm to 30nm.
[0057] The red light group 14, the blue light group 16 and the green light group 15 are as follows: Fig.12 The corresponding color coordinates in the CIE chromaticity diagram are respectively defined as a red light coordinate 141, a green light coordinate 151, and a blue light coordinate 161. The connecting lines of the red light coordinate 141, the green light coordinate 151, and the blue light coordinate 161 surround and define a light mixing area 43. The range of the light mixing area 43 includes the dimming area 42 on the CIE chromaticity diagram and the area is larger than the area of the dimming area 42.
[0058] In actual application, the control unit 2 is used to adjust the power ratio of the first white light group 11, the second white light group 12, and the third white light group 13, so that the light source unit 1 provides a basic light source close to the black body radiation line 41. Then, according to the needs, the power of the red light group 14, the green light group 15, and the blue light group 16 are adjusted to color the basic light source. For example, when red light similar to sunlight is needed for photography, after adjusting the basic light source close to the black body radiation line 41, the brightness of the red light group 14 can be adjusted according to the required saturation of the red light. In this way, a light source with red light added to the basic light source can be provided.
[0059] In summary, the first LED element 102, the second LED element 103 and the third LED element 104 emit three types of blue light with wavelengths between 410nm and 450nm, between 450nm and 470nm and between 460nm and 490nm, so that the mixed light of the fluorescent layer 105 after being excited can appear as white light with blue-green light, so as to achieve the effect of simulating sunlight. In addition, the white light generated by the white light emitting crystal grains 10 has different correlated color temperatures, and the white light generated by the white light emitting crystal grains 10 includes part of the black body radiation line 41 in the dimming area 42 in the CIE chromaticity diagram. The control unit 2 is configured to output current to control the brightness change of the white light generated by the white light emitting crystal grains 10, so that the mixed light coordinates 17 corresponding to the light source unit 1 after mixing light can be close to the black body radiation line 41 as the brightness of the white light emitting crystal grains 10 changes, so as to achieve the effect that the light emitted by the lighting device is similar to sunlight at different color temperatures, and can achieve the effect of highly restoring the true color of the object. In addition, by setting the red light group 14, the green light group 15 and the blue light group 16, after adjusting the basic light source close to the black body radiation line 41, the power of the red light group 14, the green light group 15 and the blue light group 16 can be adjusted according to the needs to dye the basic light source. In this way, it is possible to achieve good color rendering while further improving the color saturation of the mixed light source to cope with photography or various environmental applications, thereby truly achieving the purpose of the utility model.
Claims
1. A white light emitting crystal particle, characterized in that: The white light emitting crystal grain comprises: Base plate; A first light emitting diode element is disposed on the bottom plate and is capable of emitting a first blue light with a wavelength between 410nm and 450nm; A second light emitting diode element is disposed on the bottom plate and is capable of emitting a second blue light with a wavelength between 450nm and 470nm; A third light emitting diode element is disposed on the bottom plate and is capable of emitting a third blue light having a wavelength between 460nm and 490nm; and Three fluorescent layers are respectively covered on the surfaces of the first light emitting diode element, the second light emitting diode element and the third light emitting diode element. The characteristic is that when the fluorescent layer is irradiated by the first blue light, the second blue light and the third blue light respectively, the fluorescent layer will be excited to make the white light emitting crystal grain generate white light.
2. The white light emitting crystal particle according to claim 1, characterized in that: The color temperature of the first blue light emitted by the first LED element is between 2700K and 7500K, the color temperature of the second blue light emitted by the second LED element is between 2700K and 7500K, and the color temperature of the third blue light emitted by the third LED element is between 2700K and 7500K.
3. The white light emitting crystal particle according to claim 1, characterized in that: The white light generated by the white light emitting crystal grain has a color rendering index R9 greater than 91 when the ambient temperature is between 30° C. and 90° C.
4. The white light emitting crystal particle according to claim 1, characterized in that: The white light generated by the white light emitting crystal grain has a color rendering index R12 greater than 91 when the ambient temperature is between 30° C. and 90° C.
5. A lighting device, characterized in that: The lighting device comprises: A light source unit, comprising at least three white light emitting crystal particles according to any one of claims 1 to 4, wherein the color coordinates corresponding to the white light generated by the white light emitting crystal particles in the CIE chromaticity diagram are respectively defined as a first coordinate, a second coordinate and a third coordinate, the correlated color temperatures of the first coordinate, the second coordinate and the third coordinate are different from each other, the connecting line of the first coordinate, the second coordinate and the third coordinate forms two intersections with a black body radiation line, the connecting line of the first coordinate, the second coordinate and the third coordinate surrounds and defines a dimming area, characterized in that: the dimming area includes part of the black body radiation line, and the corresponding color coordinates of the light source after mixing of the light source unit in the CIE chromaticity diagram are defined as mixed light coordinates; and The control unit is electrically connected to the light source unit and is used for outputting current to the white light emitting crystal grains respectively to control the brightness change thereof respectively, so as to move the mixed light coordinates in the dimming area.
6. The lighting device according to claim 5, characterized in that: At least two of the first coordinate, the second coordinate, and the third coordinate are not located on the black body radiation line.
7. The lighting device according to claim 5, characterized in that: The first coordinate, the second coordinate, and the third coordinate are not located on the black body radiation line.
8. The lighting device according to claim 5, characterized in that: The connecting line of the first coordinate, the second coordinate and the third coordinate forms two intersections with the black body radiation line, wherein the color temperature of one of the intersections is not higher than 1800K, and the color temperature of the other intersection is not lower than 10000K.
9. The lighting device according to claim 5, characterized in that: A connecting line of the first coordinate and the third coordinate forms two intersections with the black body radiation line, wherein a color temperature of one of the intersections is not higher than 1800K, and a color temperature of the other intersection is not lower than 10000K.
10. The lighting device according to claim 5, characterized in that: The correlated color temperature of the first coordinate is between 1800 and 2600K.
11. The lighting device according to claim 10, characterized in that: The correlated color temperature of the second coordinate is between 2600 and 4500K.
12. The lighting device according to claim 11, characterized in that: The correlated color temperature of the third coordinate is between 6500 and 10000K.
13. The lighting device according to claim 5, characterized in that: The lighting device further comprises a substrate, and the white light emitting crystal particles are arranged in a staggered manner on the substrate.
14. The lighting device according to claim 5, characterized in that: The light source unit further comprises a red light group, a green light group and a blue light group which are electrically connected to the control unit and are used to emit monochromatic light. The red light group, the green light group and the blue light group respectively receive current output by the control unit to change their brightness.
15. The lighting device according to claim 14, characterized in that: The corresponding color coordinates of the red light group, the green light group and the blue light group in the CIE chromaticity diagram are respectively defined as red light coordinates, green light coordinates and blue light coordinates, and the connecting lines of the red light coordinates, the green light coordinates and the blue light coordinates surround and define a mixed light area, and the area of the mixed light area is larger than the area of the dimming area.