LED light source, backlight module, display device, and lighting device

Abstract

To provide an LED light source, a backlight module, a display device, and a lighting device that aim to improve the NTSC color gamut coverage of LED light sources and reduce the manufacturing costs of LED light sources.SOLUTION: LED light source includes a first light-emitting unit 11 and a second light-emitting unit 12, the first light-emitting unit is a first light-emitting chip, and the second light-emitting unit is a photoluminescence layer or a second light-emitting chip. The first light-emitting chip has a multi-peak emission spectrum and is arranged to emit at least blue and green light. The second light-emitting unit is configured to emit red light. The multi-peak first light-emitting chip provided by the present application, when combined with the second light-emitting unit, can reduce the manufacturing cost of the LED light source, increase the color gamut of the LED light source, and facilitate the production of a light-emitting chip with a specific light wavelength, thereby meeting the wide color gamut requirements of the display device and the specific wavelength requirements of an animal and plant cultivation lighting device.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] This application relates to the field of LED light source technology, and particularly to LED light sources, backlight modules, display devices, and lighting devices.

Background Art

[0002] A light emitting diode (LED) light source is a type of solid semiconductor cold light source, which is an optoelectronic device made by creating a PN junction using a semiconductor compound material and is commonly used in display panels. Conventionally, the light source of a display panel usually emits white light by mixing the light of three colors: red, green, and blue. Specifically, two implementation methods are common.

[0003] The first method uses three independent light emitting chips, namely a blue light emitting chip, a green light emitting chip, and a red light emitting chip. Each of the three chips emits light of the corresponding color and mixes the colors to form white light. The second method combines a green light phosphor and a red light phosphor with a blue light emitting chip. The blue light emitting chip emits blue light, and the green light phosphor and the red light phosphor are excited by the blue light emitting chip to emit green light and red light respectively. The light of the three colors, red, green, and blue, is mixed to form white light.

[0004] However, both of the above two methods have significant defects. The first method has a large number of chips and high costs, and is often applied to advertising billboard displays with a long viewing distance. The second method has a poor NTSC color gamut coverage because the wavelength purity of the green light emitted by the green light phosphor used is not sufficient (the half wavelength width is narrow), and is often applied to notebook computer (NB) panels, television (TV) panels, etc. with a short viewing distance. Solving the above problems is an issue being considered by those skilled in the art.

Summary of the Invention

[0005] Therefore, this application provides an LED light source, a backlight module, a display device, and a lighting device aimed at improving the NTSC color gamut coverage of the LED light source and reducing the manufacturing cost of the LED light source.

[0006] This embodiment provides an LED light source including a first light-emitting unit and a second light-emitting unit. The first light-emitting unit is a first light-emitting chip having a multi-peak emission spectrum and is configured to emit at least blue light and green light. The second light-emitting unit is configured to emit red light. The blue light and green light emitted by the first light-emitting unit and the red light emitted by the second light-emitting unit are mixed to produce white light.

[0007] In one preferred embodiment, the first light-emitting chip includes a first semiconductor layer, a multilayer light-emitting layer, and a second semiconductor layer, wherein a first electrode is provided on the first semiconductor layer and a second electrode is connected to the second semiconductor layer, the first electrode and the second electrode are configured to supply an electrical signal to drive the multilayer light-emitting layer to emit light, and the multilayer light-emitting layer uses the same light-emitting material.

[0008] The first semiconductor layer is an N-type semiconductor layer and the second semiconductor layer is a P-type semiconductor layer, or the first semiconductor layer is a P-type semiconductor layer and the second semiconductor layer is an N-type semiconductor layer.

[0009] In one preferred embodiment, the multilayer light-emitting layer comprises two light-emitting layers, one of which is configured to emit blue light and the other light-emitting layer is configured to emit green light.

[0010] In one preferred embodiment, the first light-emitting chip is configured to emit cyan light, and the multilayer light-emitting layer consists of three light-emitting layers, each configured to emit blue light, green light, and cyan light, respectively.

[0011] In one preferred embodiment, the second light-emitting unit is a photoluminescent layer, the second light-emitting unit is provided on the light-emitting path of the first light-emitting chip, and the second light-emitting unit is configured to be excited by the light emitted by the first light-emitting chip to form red light.

[0012] In one preferred embodiment, the second light-emitting unit is a second light-emitting chip, and the second light-emitting chip is configured to emit red light.

[0013] In one preferred embodiment, the first light-emitting chip and the second light-emitting chip are arranged stacked horizontally or vertically.

[0014] In one preferred embodiment, the first light-emitting chip and the second light-emitting chip are arranged vertically stacked, and the first light-emitting chip is located on the light-emitting path of the second light-emitting chip.

[0015] This application also provides a backlight module equipped with the above-mentioned LED light source.

[0016] Embodiments of this application further provide a display device including a display panel and the above-mentioned backlight module that supplies backlight to the display panel.

[0017] The present embodiment further provides a lighting device equipped with the above-mentioned LED light source.

[0018] The LED light source, backlight module, display device, and lighting device of this application can emit at least high-purity blue and green light by using a single chip (first light-emitting chip), and the blue and green light sources can use only the same set of electrodes, and white light is formed by mixing them with the red light emitted by the second light-emitting unit. This application can not only significantly reduce the production cost of LED light source products, but can also improve the purity of green light and improve the color gamut of the LED light source, thereby meeting the wide color gamut requirements of display devices.

[0019] This application can easily emit green light of a specific wavelength, particularly green light with a wavelength of 530 nm or less, by using a chip to emit light, compared with those that excite a photoluminescence material to emit green light. Both the technical difficulty and cost are reduced, and it can preferably satisfy the lighting needs of light of a specific wavelength required for a lighting device for the growth of animals and plants.

Brief Description of the Drawings

[0020] [Figure 1] It is a diagram showing the configuration of an LED light source according to the first embodiment of the present application. [Figure 2] It is a diagram showing the configuration of a package holder according to the first embodiment of the present application. [Figure 3] It is a diagram showing the configuration of a first light-emitting chip according to the first embodiment of the present application. [Figure 4] It is the spectrum of the cyan light emitted by the first light-emitting chip according to the first embodiment of the present application. [Figure 5] It is a diagram showing the configuration of a package holder according to the second embodiment of the present application. [Figure 6] It is a diagram showing the configuration of a first light-emitting chip according to the third embodiment of the present application. [Figure 7] It is a diagram showing an LED light source according to the fourth embodiment of the present application. [Figure 8] It is a diagram showing an LED light source according to the fifth embodiment of the present application. [Figure 9] It is a diagram showing an LED light source according to the sixth embodiment of the present application. [Figure 10] It is a diagram showing an LED light source according to the seventh embodiment of the present application. [Figure 11] It is a diagram showing an LED light source according to the eighth embodiment of the present application. [Figure 12] It is a diagram showing an LED light source according to the ninth embodiment of the present application. [Figure 13] It is a diagram showing the configuration of a backlight module according to the tenth embodiment of the present application. [Figure 14] It is a diagram showing the configuration of a backlight module according to the eleventh embodiment of the present application. [Figure 15] This is a diagram showing the configuration of the display device according to the 12th embodiment of the present application. [Figure 16] This is a diagram showing the configuration of the lighting device according to the 13th embodiment of the present application. [Figure 17] This is a diagram comparing the white light emission spectrum of the LED light source provided by the present application with the white light emission spectrum of Related Art 1. [Figure 18] This is the CIE1931 chromaticity diagram provided in the present application, which shows the comparison of the color gamut coverage of the LED light source of the present application and Related Art 1. [Figure 19] This is a statistical diagram of the coverage data of the NTSC color gamut and sRGB color gamut of Related Art 1 in FIG. 18. [Figure 20] This is a statistical diagram of the coverage data of the NTSC color gamut and sRGB color gamut of the LED light source according to the present application in FIG. 18. [Figure 21] This is the cyan light spectrum of Related Art 2.

Embodiments for Carrying Out the Invention

[0021] The present disclosure will be further described in the following detailed description in conjunction with the above drawings.

[0022] Note that the following specific embodiments are merely exemplary in nature and are not intended to limit the present invention, its applications, and / or uses. It should be understood that there are many variations. The specific embodiments enable those skilled in the art to realize the exemplary embodiments of the present invention without undue experimentation, and it should be understood that the functions and structures described in the exemplary embodiments can be variously changed or modified without departing from the scope of the present invention described in the appended claims.

[0023] Furthermore, in the description of this application, the directions and positional relationships indicated by terms such as "up," "down," "front," "back," "left," "right," "top," "bottom," "inside," and "outside" are directions and positional relationships shown based on the drawings and are defined for explanatory convenience. They do not indicate that each device or element has a specific direction or is configured and operates in a specific direction, and therefore do not limit the present invention. Also, the terms "first" and "second" are used for explanatory purposes only and should not be understood as implicitly indicating the number of technical features that indicate, suggest, or are shown to be of relative importance. Thus, features limited by "first" and "second" may explicitly or implicitly include one or more such features. Furthermore, in the description of this application, "multiple" means two or more unless specifically limited, and at least one may be one, two, or more than one.

[0024] The embodiments of this application will be described in more detail below with reference to Figures 1 to 21.

[0025] First Example Figure 1 shows the configuration of an LED light source according to the first embodiment of the present application. Figure 2 shows the configuration of a package holder according to the second embodiment of the present application.

[0026] Referring to Figure 1, the present application provides an LED light source 1 including a first light-emitting unit 11, a second light-emitting unit 12, and a package holder 13. The package holder 13 has an internal storage cavity 134, one side of which is open to form a light-emitting port 135. The first light-emitting unit 11 and the second light-emitting unit 12 are provided within the storage cavity 134 of the package holder 13, and both are capable of emitting light toward the light-emitting port 135 of the package holder 13. The first light-emitting unit 11 is configured to emit at least blue light and green light, and the second light-emitting unit 12 is configured to emit red light. The blue light and green light emitted by the first light-emitting unit 11 and the red light emitted by the second light-emitting unit 12 are mixed to form white light.

[0027] Furthermore, depending on the needs of the actual use case, for example, the needs of plant and animal cultivation lighting, the first light-emitting unit 11 may be configured to emit light of three wavelengths: blue light, green light, and cyan light.

[0028] Referring to Figure 1, the package holder 13 includes a substrate 131 and a reflective cup 132 provided on the upper side of the substrate 131. The reflective cup 132 is an annular cup shape, with the inside of the reflective cup 132 forming a storage cavity 134, and the upper opening of the reflective cup 132 forming a light outlet 135. In other words, the light outlet 135 is located on the side of the reflective cup 132 away from the substrate 131. In the first embodiment, the substrate 131 can be integrally manufactured together with the reflective cup 132 from an LCP (Liquid Crystal Polymer) material. Furthermore, in the manufacturing process, plastic particles, ceramic particles, or a highly volatile solution may be mixed into the LCP material. The light outlet 135 of the reflective cup 132 is located on the side away from the substrate 131. In some other embodiments, the substrate 131 in this application may be made of other materials or structures, such as a silver-plated copper plate, and this application is not particularly limited.

[0029] Referring to Figure 1, the reflective cup 132 is provided with a package 133 that covers the first light-emitting unit 11 and the second light-emitting unit 12. The package 133 fills the housing cavity 134 within the reflective cup 132 and protects the first light-emitting unit 11 and the second light-emitting unit 12 within the reflective cup 132.

[0030] Referring to Figure 1, the first light-emitting unit 11 is the first light-emitting chip 111, and the first light-emitting chip 111 may be a general-sized LED chip, a miniLED chip, or a MicroLED chip. Note that the LED light source 1 provided in this application is not limited to a general-sized one, but may also include miniLED and MicroLED light sources.

[0031] Figure 3 shows the configuration of the first light-emitting chip 111 according to the first embodiment of the present application.

[0032] Referring to Figure 3, the first light-emitting chip 111 includes a substrate 1111 and a low-temperature buffer layer 1112, a first semiconductor layer 1113, a multilayer light-emitting layer 1114, and a second semiconductor layer 1115 sequentially stacked on the upper side of the substrate 1111. In some embodiments, the substrate 1111 includes gallium nitride (GaN), sapphire, silicon carbide, or silicon. The low-temperature buffer layer 1112 is a GaN low-temperature buffer layer 1112.

[0033] In some embodiments, the first semiconductor layer 1113 is an N-type semiconductor layer and the second semiconductor layer 1115 is a P-type semiconductor layer, meaning the N-type semiconductor layer is located on the side of the multilayer light-emitting layer 1114 that is closer to the substrate 1111. In other embodiments, the first semiconductor layer 1113 is a P-type semiconductor layer and the second semiconductor layer 1115 is an N-type semiconductor layer, meaning the P-type semiconductor layer may be located on the side of the multilayer light-emitting layer 1114 that is closer to the substrate 1111. In other words, the positions of the N-type semiconductor layer and the P-type semiconductor layer may be swapped.

[0034] Generally, in order to maintain film deposition quality and luminous efficiency, it is preferable that the N-type semiconductor layer is located on the side of the multilayer light-emitting layer 1114 closer to the substrate 1111, and the P-type semiconductor layer is located on the side away from the substrate 1111. Furthermore, the multilayer-laminated light-emitting layer 1114 covers only a portion of the N-type semiconductor layer, and a first electrode 1116 is connected to the upper side of the N-type semiconductor layer, with the first electrode 1116 located in the portion of the N-type semiconductor layer not covered by the light-emitting layer 1114. A second electrode 1117 is connected to the upper side of the P-type semiconductor layer. The first electrode 1116 and the second electrode 1117 are configured to supply electrical signals to cause the multilayer light-emitting layer 1114 to emit light.

[0035] Furthermore, the N-type semiconductor layer is an n-doped semiconductor layer, and the P-type semiconductor layer is a p-doped semiconductor layer. Also, when the first electrode 1116 is the positive electrode, the second electrode 1117 is the negative electrode. And when the first electrode 1116 is the negative electrode, the second electrode 1117 is the positive electrode. This application does not limit this.

[0036] The multilayer light-emitting layer 1114 is a multilayer vertical stacked multiple quantum well structure (MQWs). In this embodiment, the multilayer light-emitting layer 1114 consists of two stacked light-emitting layers 1114, one of which is configured to emit blue light and the other light-emitting layer 1114 is configured to emit green light.

[0037] In this application, the term "vertical stacking" refers to stacking sequentially along the light emission direction or arranging perpendicularly to the substrate 131.

[0038] The light-emitting material of all multilayer light-emitting layers 1114 is the same; specifically, the light-emitting material of all multilayer light-emitting layers 1114 is InGaN material, and the proportion of In element in the light-emitting material that emits blue light is smaller than the proportion of In element in the light-emitting material that emits green light.

[0039] Both the blue and green light-emitting materials are InGaN, and they are stacked vertically on the first light-emitting chip 111 so that both blue and green light are emitted from the same light-emitting chip. Compared to designs where two light-emitting layers 1114 share the same set of electrodes or circuits and emit light of only one wavelength using a single light-emitting chip, this invention can significantly reduce the manufacturing cost of the LED chip. Since the blue and green light-emitting materials are the same, their lattice constants are matched, and they have few epitaxial defects, they can be stacked and grown on the same substrate 1111.

[0040] In this application, the term "double peak" refers to an LED spectrum having two emission peaks with different emission wavelengths. In this application, the term "multiple peaks" refers to an LED spectrum having multiple emission peaks, each having a different emission wavelength. The term "emission peak" refers to a local maximum value at an emission wavelength, where the emission intensity is at least twice that of a nearby or adjacent emission wavelength.

[0041] The first light-emitting chip 111 has a multi-peak emission spectrum, and specifically, the first light-emitting chip 111 is configured to emit at least blue light and green light.

[0042] Figure 4 shows the spectrum emitted by the first light-emitting chip 111 according to the first embodiment of the present application.

[0043] Referring to Figure 4, the emission spectrum of the first light-emitting chip 111 is double-peaked, and the first light-emitting chip 111 is designed to emit only blue and green light, and can be used as a backlight source for a liquid crystal display (LCD). In this embodiment, the high purity of the green light improves the color gamut of the applicable display device and can meet the requirements for a wide color gamut. In addition, it has a high color mixing effect.

[0044] Referring to Figure 1, the second light-emitting unit 12 is a photoluminescent layer 121, and the photoluminescent layer 121 may be at least one of a red phosphor and an orange phosphor. The second light-emitting unit 12 may be a red phosphor or an orange phosphor, or a mixture of both. The red phosphor includes at least one of KSiF phosphor (fluoride red phosphor) and Nitride phosphor. Similarly, the orange phosphor includes at least one of KSiF phosphor (fluoride red phosphor) and Nitride phosphor.

[0045] While red and orange phosphors are dispersed along the light-emitting path of the first light-emitting chip 111, it should be understood that the red and orange phosphors are dispersed within the package 133.

[0046] Furthermore, the red or orange phosphor in this embodiment is a photoluminescent material in the wavelength range of 580 nm to 800 nm. In other embodiments, a photoluminescent material in a different wavelength range may be selected depending on the application requirements.

[0047] Second Embodiment Figure 5 shows the configuration of the package holder 12 according to the second embodiment of the present application. Referring to Figure 3, the difference between the second embodiment and the first embodiment is that the substrate 131 and the reflective cup 132 are made from different materials. For example, the substrate 131 is a silicon substrate 131, a plastic substrate 131, or a ceramic substrate 131, and the reflective cup 132 is made from LCP material.

[0048] Third Embodiment Figure 6 shows the configuration of the first light-emitting chip 111 according to the third embodiment of the present application.

[0049] Referring to Figure 6, the difference between the third embodiment and the first embodiment is that the multilayer light-emitting layer 1114 is a stacked three-layer light-emitting layer 1114, configured to emit blue light, green light, and cyan light, respectively. In other words, the emission spectrum of the first light-emitting chip 111 has three peaks. Typically, the wavelength of cyan light is between 480 nm and 500 nm. The light-emitting material of the three layers of light-emitting layer 1114 is InGaN, and the proportion of In element decreases in the order of the light-emitting material for emitting blue light, the light-emitting material for emitting cyan light, and the light-emitting material for emitting green light.

[0050] This embodiment can be applied to the field of lighting fixtures for animals and plants. In plant lighting, the wavelength of blue light is typically between 400nm and 499nm, the wavelength of green light is between 500nm and 599nm, the wavelength of red light is between 600nm and 699nm, and the wavelength of far-red light is between 700nm and 780nm. Depending on the growing lighting needs of different animals and plants, the first light-emitting chip 111 can be configured to emit light in multiple different color combinations, and this application does not particularly limit this.

[0051] Fourth Embodiment Figure 7 shows an LED light source 1 according to the fourth embodiment of the present application. Referring to Figure 7, the difference between the fourth embodiment and the first embodiment is that the second light-emitting unit 12 is a second light-emitting chip 122, the second light-emitting chip 122 is a red LED chip, and the second light-emitting chip 122 is configured to emit red light. The second light-emitting chip 122 includes an epitaxial red light-emitting layer using a red light-emitting material, and the red light-emitting material may be an AlGaInP material.

[0052] Referring to Figures 2 and 7, the first light-emitting chip 111 and the second light-emitting chip 122 are stacked on top of each other in a direction perpendicular to the substrate 131. In this embodiment, as a preferred embodiment, the first light-emitting chip 111 is located on the light-emitting path of the second light-emitting chip 122. Specifically, the second light-emitting chip 122 is located on one side away from the light-emitting port 135 of the first light-emitting chip 111, that is, as shown in Figure 7, the second light-emitting chip 122 is located below the first light-emitting chip 111. This makes it possible to reduce the overall size of the LED light source 1 and save mounting space.

[0053] Because red light has a long wavelength, its energy gap is small, while blue light has a short wavelength, resulting in a large energy gap. Therefore, red light can cross the energy gap of the blue light-emitting material. Furthermore, when a sapphire substrate is used as the substrate 1111, the sapphire substrate has a larger energy gap and is transparent to both blue and red light. Therefore, in this embodiment, the luminescence efficiency can be increased by placing the second light-emitting chip 122 on one side of the first light-emitting chip 111 away from the light-emitting port 135.

[0054] Referring to Figure 7, the first light-emitting chip 111 is fixed in the package holder 13 using a face-up mounting method, meaning that the first electrode 1116 and the second electrode 1117 of the first light-emitting chip 111 are positioned away from the substrate 131. The second light-emitting chip 122 is fixed in the package holder 13 using a flip-chip method, meaning that the electrodes of the second light-emitting chip 122 are both positioned facing the substrate 131. The material of the substrate 1111 of the first light-emitting chip 111 and the second light-emitting chip 122 should be a material with a large energy gap to avoid light blocking by the substrate 1111; otherwise, the substrate 1111 of the first light-emitting chip 111 and the second light-emitting chip 122 will eventually be peeled off to improve luminescence efficiency.

[0055] Fifth Embodiment Figure 8 shows an LED light source 1 according to the fifth embodiment of the present application.

[0056] Referring to Figure 8, the fifth embodiment differs from the first embodiment in that the first light-emitting chip 111 and the second light-emitting chip 122 are arranged horizontally within the package holder 13. In this application, the term "arranged horizontally" refers to both being arranged in a direction parallel to the substrate 131.

[0057] The first light-emitting chip 111 and the second light-emitting chip 122 are both fixed within the package holder 13 using a flip-chip mounting method. In other words, the electrodes of both the first light-emitting chip 111 and the second light-emitting chip 122 are positioned facing the substrate 131, thus avoiding the electrodes occupying the light-emitting area and affecting the luminous efficiency. The material of the substrate 1111 for the first light-emitting chip 111 and the second light-emitting chip 122 should be a material with a large energy gap to avoid light blocking by the substrate 1111; otherwise, the substrate 1111 for the first light-emitting chip 111 and the second light-emitting chip 122 will eventually be peeled off to improve the luminous efficiency.

[0058] Sixth Embodiment Figure 9 shows an LED light source 1 according to the sixth embodiment of the present application.

[0059] Referring to Figure 9, the sixth embodiment differs from the first embodiment in that the first light-emitting chip 111 and the second light-emitting chip 122 are arranged horizontally. The first light-emitting chip 111 is fixed in the package holder 13 using a face-up chip mounting method. That is, both the first electrode 1116 and the second electrode 1117 of the first light-emitting chip 111 are positioned away from the substrate 131. The second light-emitting chip 122 is fixed in the package holder 13 using a vertical mounting method. That is, one electrode of the second light-emitting chip 122 is positioned facing the substrate 131, and the other electrode is positioned away from the substrate 131.

[0060] Furthermore, when the first light-emitting chip 111 and the second light-emitting chip 122 are arranged horizontally, the first light-emitting chip 111 and the second light-emitting chip 122 can each be mounted using one of the following methods: face-up mounting, vertical mounting, or flip-chip mounting. This application does not cover all combinations of mounting configurations for the first light-emitting chip 111 and the second light-emitting chip 122, but only provides illustrative examples in Figures 7, 8, and 9.

[0061] Seventh Embodiment Figure 10 shows an LED light source 1 according to the seventh embodiment of the present application.

[0062] Referring to Figure 10, the seventh embodiment differs from the first embodiment in that the mounting configuration of the first light-emitting chip 111 is different. In the seventh embodiment, the first light-emitting chip 111 is mounted in a chip-size package (ChipScalePackage, abbreviated as CSP), the first light-emitting chip 111 has five light-emitting surfaces, the photoluminescence layer 121 is at least one of red phosphor or orange phosphor, and the photoluminescence layer 121 encloses the five light-emitting surfaces of the first light-emitting chip 111.

[0063] In other embodiments, the first light-emitting chip 111 may have four light-emitting surfaces or emit light from one side, and this disclosure does not particularly limit it.

[0064] In other embodiments, the first light-emitting chip 111 may be in an NCSP (Near Chip Scale Package) package, and this application does not particularly limit it.

[0065] Eighth Embodiment Figure 11 shows the configuration of the LED light source 1 according to the first embodiment of the present application.

[0066] Referring to Figure 11, the difference between the eighth embodiment and the seventh embodiment is that the photoluminescence layer 121 is a thin-film photoluminescence layer, and a thin-film photoluminescence material, such as a QD photoluminescence material, is used for the thin-film photoluminescence layer. The size of the thin-film photoluminescence layer can be designed as needed; for example, in the eighth embodiment, the size of the thin-film photoluminescence layer approaches the size of the first light-emitting chip 111 after it has been mounted in a CSP or NCSP package, and the thin-film photoluminescence material can be attached to the light-emitting surface directly above the first light-emitting chip 111. In some other embodiments, the photoluminescence layer 121 is a relatively large thin-film photoluminescence layer that covers the light-emitting surfaces of multiple first light-emitting chips 111.

[0067] Ninth Embodiment Figure 12 shows an LED light source 1 according to the ninth embodiment of the present application.

[0068] Referring to Figure 12, the difference between the ninth embodiment and the eighth embodiment is that the first light-emitting chip 111 is a package structure that includes a package holder 13, and specifically, the first light-emitting chip 111 is a flip chip.

[0069] Tenth Embodiment Figure 13 shows the configuration of the backlight module 2 according to the tenth embodiment of the present application.

[0070] Referring to Figure 13, the tenth embodiment of the present application provides a backlight module 2 including a back plate 21 and a plurality of LED light sources 1 described in any of the above embodiments connected to the back plate 21.

[0071] 11th Example Figure 14 shows the configuration of the backlight module 2 according to the 11th embodiment of the present application.

[0072] Referring to Figure 14, the tenth embodiment of the present application provides a backlight module 2 including a back plate 21, a plurality of first light-emitting chips 111 connected on the back plate 21, and a single photoluminescence layer 121. The first light-emitting chips 111 are the first light-emitting chips 111 described in any of the embodiments described above. The photoluminescence layer 121 is a thin-film photoluminescence layer and is large enough to cover the light-emitting surfaces of the plurality of first light-emitting chips 111.

[0073] 12th Example Figure 15 shows the configuration of the display device 3 according to the twelfth embodiment of the present application.

[0074] Referring to Figure 15, the twelfth embodiment of the present application provides a display device 3 comprising a display panel 31 and the backlight module 2 described above. The display panel 31 is a liquid crystal display panel (LCD), and the backlight module 2 provides backlight to the display panel 31. The backlight module 2 is usually located at the bottom of the display device 3, and the shape and size of the backlight module 2 are matched to the shape and size of the display device 3. The display panel 31 is located on the light-emitting side of the backlight module 2 and is used to realize image display. The display device 3 can employ a direct-lit backlight or a side-in backlight configuration, but the present application is not particularly limited.

[0075] 13th Embodiment Figure 16 shows the configuration of the lighting device 4 according to the 13th embodiment of the present application.

[0076] Referring to Figure 16, the 13th embodiment of the present application provides a lighting device 4 that includes the LED light source 1 disclosed above and is applicable to the field of lighting for the growth of plants and animals.

[0077] Figure 17 shows a comparison of the white emission spectrum of the LED light source 1 provided in this application with the white emission spectrum of related technology 1. Figure 18 is a CIE1931 chromaticity diagram provided in this application, showing a comparison of the color gamut coverage of the LED light source in this application with that of related technology 1. Figure 19 is a statistical diagram of the coverage data in the NTSC and sRGB color gamuts of related technology 1 in Figure 18. Figure 20 is a statistical diagram of the coverage data in the NTSC and sRGB color gamuts of the LED light source 1 according to this application in Figure 18.

[0078] Of these, related technology 1, shown in Figures 17, 18, and 19, emits white light by combining a blue light-emitting chip with a β-SiAlON green phosphor and a KSiF red phosphor.

[0079] Referring to Figures 17 and 18, the method of incorporating β-SiAlON green phosphor and KSiF red phosphor into a blue light-emitting chip is the mainstream method for wide-color-gamut LCD displays, and its emission spectrum is L1 in Figure 17. The emission spectrum of the LED light source 1 provided in this application is L2 in Figure 17. The material properties of the green phosphor are its excitation spectrum, and because its half-wavewidth A is large, the color purity of the light is poor, which is the reason why the color gamut of the LED light source cannot be improved in related technology 1.

[0080] Referring to Figure 4, compared to related technology 1, this application changes the emission mode of green light from photoexcitation light to electroluminescence, and integrates green light and blue light onto the same LED chip (first light-emitting chip 111). The emission spectrum of the first light-emitting chip 111 shown in Figure 4 is a double peak, and both the emitted blue light and green light are of high purity, resulting in a wide color gamut effect as shown in Figures 18 and 20.

[0081] Referring to Figures 17 and 18, the LED light source 1 used in this application has a green wavelength half-wavewidth B of the emission spectrum of the first light-emitting chip 111 that is shorter than the green wavelength half-wavewidth A of related technology 1 (a configuration in which a green phosphor is incorporated into a pure blue LED chip) (A>B). In other words, the half-wavewidth of the waveform emitted by the material of the LED itself (the material of the light-emitting layer 1114 is usually InGaN) is narrower than that of the excitation phosphor, resulting in higher color purity. Because the green wavelength half-width of the first light-emitting chip 111 in this application is narrower, the green color purity on the CIE chromaticity diagram is purer, the color gamut coverage is greater, the color gamut of the LED light source 1 is extremely wide, and the wide color gamut requirement of the display device 3 can be met.

[0082] Referring to Figures 19 and 20, the NTSC color gamut coverage of related technology 1 is only 90% at best. However, the LED light source 1 provided in this application can improve the coverage of the NTSC color gamut to more than 100%.

[0083] Furthermore, the first light-emitting chip 111 has a narrower half-width in the green wavelength band of its emission spectrum than fluorescent powder, and because LED chips allow for easier adjustment of the wavelength band than fluorescent powder, it is possible to achieve green wavelength bands that are not possible with fluorescent powder. Commercially available green phosphors have difficulty exciting light in the wavelength band below 530 nm, and green phosphors in the 529 nm band are quite expensive. Currently, there are no manufacturers of green phosphors that support the 520 nm and 510 nm bands. The proposed technology allows for adjustment between 510 nm and 540 nm through chip emission, satisfying the light wavelength requirements of 520 nm and 510 nm. The proposed technology further reduces manufacturing costs and can meet the specific light wavelength requirements necessary for illuminating plants and animals.

[0084] Figure 21 shows the cyan light spectrum of Related Technology 2. Related Technology 2 is an LED light-emitting chip in which a blue light-emitting material and a green light-emitting material are mixed in the same light-emitting layer. In addition, Related Technology 2 shown in Figure 21 is electroluminescent, similar to the first light-emitting chip 111 provided in this application. However, in Related Technology 2, the blue light-emitting material and the green light-emitting material are not vertically stacked, but are mixed in the same light-emitting layer to adjust the light wave from the blue band to the green band. As a result, a single-peak cyan light spectrum like the one shown in Figure 21 is obtained in Related Technology 2.

[0085] The double-peak blue-green light spectrum provided by the present invention, shown in Figure 4, shows improved purity of blue and green light emitted by the LED light source 1 provided by the present invention, and an improved color gamut, compared to the cyan light spectrum of related technology 2 shown in Figure 21.

[0086] The LED light source 1 used in this invention integrates blue light and green light sources on the same chip (first light-emitting chip 111), resulting in lower manufacturing costs compared to LEDs that use separate light-emitting chips for blue light and green light.

[0087] Furthermore, the LED light source 1 employed in this invention stacks light-emitting materials of different wavelengths vertically on a single chip. Compared to other related technologies, such as those in which different light-emitting chips are arranged horizontally within a package holder 13 and emit blue and green light respectively, the LED light source 1 of this invention can avoid color shift at close range and has a high color mixing effect.

[0088] As described above, the multi-peaked first light-emitting chip 111 provided in this application, when combined with the second light-emitting unit 12, not only reduces the manufacturing cost of the LED light source but also widens the color gamut of the LED light source and makes it easier to create light-emitting chips of specific wavelengths, thereby satisfying the wide color gamut requirement of the display device 3 and the specific wavelength requirement of the plant and animal cultivation lighting device 4.

[0089] The specific embodiments of this application have been described above with reference to the drawings. However, it will be understood by those skilled in the art that various modifications and substitutions are possible with respect to the specific embodiments of this application without departing from the spirit and scope of this application. All of these modifications and substitutions are included within the limited claims of this application. Explanation of Reference Numerals in Drawings

[0090] Explanation of symbols LED light source 1 First light-emitting unit 11 First light-emitting chip 111 Circuit board 1111 Low-temperature buffer layer 1112 First semiconductor layer 1113 Light-emitting layer 1114 Second semiconductor layer 1115 1st electrode 1116 2nd electrode 1117 Second light-emitting unit 12 Photoluminescent layer 121 Second light-emitting chip 122 Package holder 13 Circuit board 131 Reflective cup 132 Package 133 134 storage cavities Idemitsu Exit 135 Backlight module 2 Backplate 21 Display device 3 Display panel 31 Lighting device 4

Claims

1. LED light source, A first light-emitting chip having a multi-peak emission spectrum, comprising a first light-emitting unit configured to emit at least cyan light, blue light, and green light, It comprises a second light-emitting unit that emits red light, The cyan, blue, and green light emitted by the first light-emitting unit and the red light emitted by the second light-emitting unit are mixed to produce white light. The first light-emitting chip includes a first semiconductor layer, a multilayer light-emitting layer, and a second semiconductor layer. A first electrode is provided on the first semiconductor layer, and a second electrode is connected to the second semiconductor layer. The first electrode and the second electrode are configured to supply electrical signals to drive the multilayer light-emitting layer to emit light. The aforementioned multilayer light-emitting layer uses the same light-emitting material, The first semiconductor layer is an N-type semiconductor layer and the second semiconductor layer is a P-type semiconductor layer, or the first semiconductor layer is a P-type semiconductor layer and the second semiconductor layer is an N-type semiconductor layer. The LED light source is characterized in that the multilayer light-emitting layer consists of three light-emitting layers, and each of the three light-emitting layers is configured to emit blue light, green light, and cyan light, respectively.

2. The LED light source according to claim 1, characterized in that the second light-emitting unit is a photoluminescent layer, the second light-emitting unit is provided on the light-emitting path of the first light-emitting chip, and the second light-emitting unit is configured to be excited by the light emitted by the first light-emitting chip to form red light.

3. The LED light source according to claim 1, characterized in that the second light-emitting unit is a second light-emitting chip, and the second light-emitting chip is configured to emit red light.

4. The LED light source according to claim 3, characterized in that the first light-emitting chip and the second light-emitting chip are arranged horizontally or stacked vertically.

5. The LED light source according to claim 3, characterized in that the first light-emitting chip and the second light-emitting chip are arranged in a vertical stack, and the first light-emitting chip is located on the light-emitting path of the second light-emitting chip.

6. A backlight module characterized by comprising an LED light source according to any one of claims 1 to 5.

7. A display device, Display panel and A display device comprising a backlight module according to claim 6 that supplies a backlight to the display panel.

8. A lighting device characterized by comprising an LED light source according to any one of claims 1 to 5.

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