Backlight module, quantum dot light source, display screen and electronic equipment

Abstract

The invention relates to the technical field of electronic equipment, and provides a backlight module, a quantum dot light source, a display screen and electronic equipment. The backlight module comprises a light guide layer, a reflecting layer, an excitation light source and a quantum dot light-emitting layer, the light guide layer and the reflection layer are laminated; the excitation light source is used for emitting excitation light to the light guide layer; the quantum dot light-emitting layer is arranged between the excitation light source and the light guide layer or arranged on the side, away from the reflecting layer, of the light guide layer, the quantum dot light-emitting layer comprises at least two first quantum dot materials, and the at least two first quantum dot materials can generate red light of at least two wavebands under excitation of excitation light. The backlight module disclosed by the invention can emit the backlight containing the red light of at least two wave bands, the aim of protecting eyes healthily can be achieved by utilizing the relieving characteristic of the red light of different wave bands to eyeballs of a human body, the high-color-gamut display effect of a display screen can be realized, and the image display clarity and accuracy of the display screen can be ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic equipment, and in particular to a backlight module, a quantum dot light source, a display screen and an electronic device. Background Art

[0002] Currently, the display screens of electronic devices mainly display images based on the light source provided by the backlight module. In actual applications, it has been found that the design of the backlight module is unreasonable, and the blue light band it emits is strong. Users who use electronic devices for a long time are prone to eye fatigue and vision damage. In addition, due to the design defects of the backlight module, the display screen will also have color distortion or insufficient brightness in the image display, affecting the user experience. Summary of the Invention

[0003] The present invention provides a backlight module, a quantum dot light source, a display screen and an electronic device, which are used to at least solve or improve the problem that the light emission of the existing backlight module is not conducive to human eye protection and it is difficult to ensure the image display effect of the display screen.

[0004] In a first aspect, the present invention provides a backlight module, comprising: A light guiding layer and a reflective layer, wherein the light guiding layer and the reflective layer are stacked; an excitation light source, configured to emit excitation light toward the light guiding layer; A quantum dot light-emitting layer is arranged between the excitation light source and the light-guiding layer, or on the side of the light-guiding layer away from the reflective layer. The quantum dot light-emitting layer includes at least two first quantum dot materials, and the at least two first quantum dot materials can generate red light of at least two bands under the excitation of the excitation light.

[0005] According to a backlight module provided by the present invention, the excitation light source includes a blue light LED chip or an ultraviolet light LED chip.

[0006] According to a backlight module provided by the present invention, the at least two first quantum dot materials can generate red light including a 620 nm band and a 650 nm band under the excitation of the excitation light.

[0007] According to a backlight module provided by the present invention, the half-value width of at least one of the 620 nm band and the 650 nm band is 10-40 nm.

[0008] According to a backlight module provided by the present invention, the excitation light source is used to emit blue excitation light; The quantum dot light-emitting layer further includes a second quantum dot material, which can generate green light under the excitation of the blue excitation light.

[0009] According to a backlight module provided by the present invention, in the quantum dot light-emitting layer, the proportion of the first quantum dot material is greater than the proportion of the second quantum dot material; Alternatively, the quantum dot light-emitting layer further includes red phosphor, and the red phosphor can generate red light under the excitation of the blue excitation light.

[0010] According to a backlight module provided by the present invention, the excitation light source is used to emit blue excitation light; The quantum dot light-emitting layer further includes red phosphor and green phosphor. The red phosphor can generate red light under the excitation of the blue excitation light, and the green phosphor can generate green light under the excitation of the blue excitation light.

[0011] According to a backlight module provided by the present invention, the first quantum dot material includes any one of cadmium selenide, a composite material of cadmium selenide and zinc sulfide, indium phosphide, perovskite and copper indium sulfide.

[0012] In a second aspect, the present invention further provides a quantum dot light source, comprising the excitation light source and a quantum dot light-emitting layer as described above, wherein the quantum dot light-emitting layer is provided at the light-emitting end of the excitation light source.

[0013] A quantum dot light source provided by the present invention further includes: A transparent protective layer is coated on a side of the quantum dot light-emitting layer away from the light-emitting end.

[0014] In a third aspect, the present invention further provides a display screen comprising: a liquid crystal display layer and the backlight module as described above; In the case where the quantum dot light-emitting layer is provided between the excitation light source and the light guide layer, the liquid crystal display layer is provided on a side of the light guide layer away from the reflective layer; In a case where the quantum dot light-emitting layer is disposed on a side of the light-guiding layer away from the reflective layer, the liquid crystal display layer is disposed on a side of the quantum dot light-emitting layer away from the light-guiding layer.

[0015] In a fourth aspect, the present invention further provides an electronic device, comprising: a housing and the display screen as described above, wherein the display screen is provided on the housing.

[0016] An electronic device provided according to the present invention further includes: An ambient light sensor, used to collect light intensity information of the environment in which the electronic device is located; The control module is electrically connected to the ambient light sensor and the excitation light source respectively, and is used to control the luminous state of the excitation light source according to the light intensity information fed back by the ambient light sensor to adjust the luminous intensity of the backlight module.

[0017] The backlight module, quantum dot light source, display screen and electronic device provided by the present invention are configured with a light guiding layer, a reflective layer, an excitation light source and a quantum dot light-emitting layer in the backlight module, and at least two first quantum dot materials are configured in the quantum dot light-emitting layer. The excitation light emitted by the excitation light source can be directly used to excite the first quantum dot material, so that the quantum dot light-emitting layer outputs backlight containing at least two bands of red light. After the light is irradiated on the light guiding layer, the backlight is ensured to be output from the side of the light guiding layer away from the reflective layer based on the reflection effect of the reflective layer. Alternatively, the excitation light emitted by the excitation light source can be incident on the light guiding layer. After the excitation light is irradiated on the light guiding layer, the excitation light is ensured to be irradiated on the quantum dot light-emitting layer based on the reflection effect of the reflective layer, and the first quantum dot material is excited, so that the quantum dot light-emitting layer outputs backlight containing at least two bands of red light. Both of these optical path designs can output backlight containing at least two bands of red light. The soothing properties of red light of different bands on the human eye can be utilized to achieve the purpose of healthy eye protection and effectively reduce the harm of blue light to the human eye.

[0018] At the same time, compared with the traditional red light excitation based on narrow-band red phosphor (KSF), the present invention excites red light based on at least two first quantum dot materials, which can not only achieve the output of red light in multiple bands, but also overcome the problems of brightness attenuation and color drift existing in traditional narrow-band red phosphors during high-temperature use, and can achieve a high color gamut display effect, ensuring the clarity and accuracy of the image displayed on the display screen. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 This is one of the structural schematic diagrams of the display screen provided by the present invention.

[0021] Figure 2 This is the second structural schematic diagram of the display screen provided by the present invention.

[0022] Figure 3 This is one of the structural schematic diagrams of the quantum dot light-emitting layer provided by the present invention.

[0023] Figure 4 This is the second structural schematic diagram of the quantum dot light-emitting layer provided by the present invention.

[0024] Figure 5 This is the third structural schematic diagram of the quantum dot light-emitting layer provided by the present invention.

[0025] Figure 6 It is a spectrum curve diagram of light emitted by a display screen in the prior art.

[0026] Figure 7 This is a spectrum curve diagram of the light emitted by the display screen provided by the present invention.

[0027] Figure 8 This is a spectrum comparison curve of the traditional lamp beads and quantum dot light sources provided by the present invention.

[0028] Reference numerals: 1. Light guide layer; 2. Reflection layer; 3. Excitation light source; 4. Quantum dot light emitting layer; 5. Liquid crystal display layer; 6. Support layer; 7. Light collecting layer; 8. Transparent cover plate; 100. Transparent base layer; 101. First quantum dot material; 102. Second quantum dot material; 103. Red phosphor; 104. Green phosphor. DETAILED DESCRIPTION

[0029] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0030] The following combination Figures 1-8 , the backlight module, quantum dot light source, display screen and electronic device provided by the embodiments of the invention are described in detail through specific embodiments and their application scenarios.

[0031] In the first aspect, Figure 1 and Figure 2 As shown, an embodiment of the present invention provides a backlight module, comprising: a light guide layer 1, a reflective layer 2, an excitation light source 3 and a quantum dot light emitting layer 4; The light guide layer 1 and the reflective layer 2 are stacked, and the excitation light source 3 is used to emit excitation light toward the light guide layer 1; The quantum dot light-emitting layer 4 is arranged between the excitation light source 3 and the light-guiding layer 1, or on the side of the light-guiding layer 1 away from the reflective layer 2. The quantum dot light-emitting layer 4 includes at least two first quantum dot materials 101. The at least two first quantum dot materials 101 can generate at least two bands of red light under the excitation of the excitation light.

[0032] It can be understood that the excitation light source 3 can be a point light source, the excitation light source 3 is arranged on one side of the light guide layer 1, and the excitation light source 3 can select a blue light LED chip or an ultraviolet light LED chip. The blue light LED chip is used to emit blue excitation light, and the wavelength of the blue excitation light can be 450nm or 460nm. The blue excitation light is preferably in a band with a peak close to 450nm to reduce the damage of blue light to the human eye. The ultraviolet light LED chip is used to emit ultraviolet light, and the wavelength of the ultraviolet light can be 365-405nm.

[0033] In practical applications, after light enters the light-guiding layer 1, the reflective effect provided by the reflective layer 2 ensures that the light-guiding layer 1 outputs light uniformly in the form of a surface light source. When the quantum dot light-emitting layer 4 is disposed between the excitation light source 3 and the light-guiding layer 1, the excitation light emitted by the excitation light source 3 is incident on the quantum dot light-emitting layer 4, and the quantum dot light-emitting layer 4 outputs light containing at least two bands of red light. After irradiating the light-guiding layer 1, the light is output from the side of the light-guiding layer 1 facing away from the reflective layer 2. When the quantum dot light-emitting layer 4 is disposed on the side of the light-guiding layer 1 facing away from the reflective layer 2, the excitation light emitted by the excitation light source 3 is irradiated on the light-guiding layer 1, and then output from the side of the light-guiding layer 1 facing away from the reflective layer 2 to the quantum dot light-emitting layer 4, and then the quantum dot light-emitting layer 4 outputs light containing at least two bands of red light. The light shown in this embodiment includes at least excitation light in addition to red light. Of course, when the quantum dot light-emitting layer 4 is also provided with other quantum materials that can be excited by the excitation light and are different from the first quantum dot material 101, the light shown in this embodiment should also include the light generated by the other quantum materials after being excited by the excitation light, such as green light.

[0034] For example, light guide layer 1 can be a polymethyl methacrylate (PMMA) layer, ensuring a light transmittance of 92% or greater. Alternatively, light guide layer 1 can be a polycarbonate (PC) layer. For example, reflective layer 2 can be a white polyethylene terephthalate (PET) layer or a white polycarbonate layer.

[0035] At the same time, if Figure 3 、 Figure 4 and Figure 5As shown, the quantum dot light-emitting layer 4 has a transparent base layer 100. The transparent base layer 100 can be made of materials such as epoxy resin or silicone. At least two first quantum dot materials 101 are evenly dispersed in the transparent base layer 100. Each first quantum dot material 101 can generate red light when excited by excitation light. The at least two first quantum dot materials 101 can be understood as first quantum dot materials 101 of the same particle size, but of different material types, or first quantum dot materials 101 of the same material type, but of different particle sizes. Therefore, by setting the particle size or material type of the first quantum dot material 101, it can be ensured that the first quantum dot material 101 generates red light in the wavelength band corresponding to its selection when excited by excitation light.

[0036] For quantum dot materials of the same material type, the smaller the particle size of the quantum dot material, the stronger the quantum confinement effect, the larger the energy level gap, and the shorter the emission wavelength (bluer), while the larger the particle size of the quantum dot material, the weaker the quantum confinement effect, the smaller the energy level gap, and the longer the emission wavelength (redder). Therefore, by adjusting the particle size of the quantum dot material, its emission wavelength can be precisely controlled.

[0037] For example, by configuring the quantum dot light-emitting layer 4 with first quantum dot materials 101 having at least two particle sizes, it is possible to ensure that the quantum dot light-emitting layer 4 outputs red light in at least two wavelength bands after the excitation light is irradiated onto the quantum dot light-emitting layer 4. The particle size of the first quantum dot material 101 can be 3-6 nm.

[0038] Because quantum materials of different materials have different energy band structures, the size of the band gap directly affects the emission wavelength: the smaller the band gap, the longer the emission wavelength (redder), while the larger the band gap, the shorter the emission wavelength (bluer). For example, the band structures of perovskite quantum dots and nitride-based semiconductors are different, resulting in different red light wavelengths when excited by blue light. By adjusting the material type of the quantum dot material, its emission wavelength can also be precisely controlled.

[0039] For example, by configuring the quantum dot light-emitting layer 4 with at least two types of first quantum dot materials 101, it is possible to ensure that the quantum dot light-emitting layer 4 outputs red light in at least two wavelengths after the excitation light is irradiated onto the quantum dot light-emitting layer 4. The first quantum dot material 101 includes any one of cadmium selenide, a composite material of cadmium selenide and zinc sulfide, indium phosphide, perovskite, and copper indium sulfide.

[0040] Among them, this embodiment adopts Figure 6 The spectral curve of the light emitted by the display screen in the prior art is shown, and the Figure 7 The spectrum curve of the light emitted by the display screen provided by the present invention is shown as follows: Figure 6It can be seen that in the red light band with a wavelength of 620-750nm, the red light emitted by the backlight module corresponding to the display screen has no obvious peak. Figure 7 It can be seen that in the red light band with a wavelength of 620-750nm, the red light emitted by the backlight module corresponding to the display screen forms two peaks, one peak is formed at 620nm and the other peak is formed at 655nm.

[0041] As can be seen from the above, the backlight module shown in the present invention, by setting a light guide layer 1, a reflective layer 2, an excitation light source 3 and a quantum dot light-emitting layer 4, and configuring at least two first quantum dot materials 101 for the quantum dot light-emitting layer 4, can directly use the excitation light emitted by the excitation light source 3 to excite the first quantum dot material 101, so that the quantum dot light-emitting layer 4 outputs backlight containing at least two bands of red light. After the light is irradiated on the light guide layer 1, based on the reflection effect of the reflective layer 2, it is ensured that the backlight is output from the side of the light guide layer 1 away from the reflective layer 2. Alternatively, the excitation light emitted by the excitation light source 3 can be incident on the light guide layer 1. Based on the reflection effect of the reflective layer 2, it is ensured that the excitation light is irradiated on the quantum dot light-emitting layer 4 and excites the first quantum dot material 101, so that the quantum dot light-emitting layer 4 outputs backlight containing at least two bands of red light. Both of these optical path designs can output backlight containing at least two bands of red light. The soothing properties of red light in different bands on the human eye can be utilized to achieve the purpose of healthy eye protection and effectively reduce the harm of blue light to the human eye.

[0042] At the same time, compared with the traditional red light excitation based on narrow-band red phosphor (KSF), the embodiment of the present invention is based on at least two first quantum dot materials 101 for red light excitation, which can not only achieve the output of red light in multiple bands, but also overcome the problems of brightness attenuation and color drift existing in the high-temperature use of traditional narrow-band red phosphor 103, and can achieve a high color gamut display effect, ensuring the clarity and accuracy of the image displayed on the display screen.

[0043] In some embodiments, at least two first quantum dot materials 101 can generate red light including a 620 nm band and a 650 nm band under the excitation of excitation light.

[0044] It can be understood that the 620nm band is a band in which red light generates a peak near a wavelength of 620nm, and the 650nm band is a band in which red light generates a peak near a wavelength of 650nm.

[0045] It's common knowledge that melatonin is a key hormone regulating the human circadian rhythm. It not only affects sleep but is also associated with various physiological functions, including immunity and antioxidant function. In practical applications, this invention introduces red light in the 620nm band. Electronic devices using a backlight module based on this invention can incorporate a spectral-temporal modulation model algorithm to simultaneously maintain human circadian rhythms and visual health during different time periods, from day to night. This addresses the problem that traditional night viewing modes only ensure normal melatonin secretion but fail to address visual health.

[0046] At the same time, the present invention can achieve a positive impact on the retinal blood flow of the human eye based on the red light in the 650nm band, improve the color quality, and enhance the visual comfort of the human eye by introducing red light in the 650nm band.

[0047] Furthermore, for students who use electronic devices such as tablets and learning machines to study, since electronic devices can simultaneously emit red light in the 620nm band and the 650nm band, they can also ensure the effective secretion of neurotransmitters such as cortisol and dopamine in different time periods, thereby ensuring students' homework efficiency.

[0048] Of course, in actual applications, by adjusting the particle size or material type of the first quantum dot material 101, it can be ensured that the at least two first quantum dot materials 101 shown in the present invention can also produce red light in other bands under the excitation of excitation light, such as red light in the 610nm band, 630nm band and 670nm band, and there is no specific limitation on this.

[0049] In some embodiments, the half-value width of at least one of the 620 nm band and the 650 nm band is 10-40 nm.

[0050] It can be understood that in actual applications, by adjusting the particle size or material type of the first quantum dot material 101, the half-width of at least one of the 620nm band and the 650nm band can be set to 10nm, 20nm, 30nm, 40nm or other suitable values ​​according to actual needs.

[0051] Exemplarily, the half-value widths of the 620 nm band and the 650 nm band can both be set within a range of 10-40 nm, and the half-value width of the 620 nm band is smaller than that of the 650 nm band.

[0052] For example, Figure 7 As shown, for the 620 nm band with a peak at 620 nm, the half-peak width of the 620 nm band is 20 nm, and for the 650 nm band with a peak at 655 nm, the half-peak width of the 650 nm band is 40 nm.

[0053] In some embodiments, as Figure 3As shown, the excitation light source 3 is used to emit blue excitation light, and the quantum dot light-emitting layer 4 further includes a second quantum dot material 102. The second quantum dot material 102 can generate green light under the excitation of the blue excitation light.

[0054] It can be understood that for traditional film materials, the present invention can use the first quantum dot material 101 to completely replace the red phosphor in the traditional quantum film material, and use the second quantum dot material 102 to completely replace the green phosphor in the traditional quantum film material. This makes the quantum dot light-emitting layer 4 of the embodiment of the present invention contain both the first quantum dot material 101 and the second quantum dot material 102. Under the excitation of blue excitation light, it can be ensured that the light emitted by the quantum dot light-emitting layer 4 appears as white light because it contains blue excitation light, red light and green light. This white light can be used as the backlight of the display screen. The brightness response of this backlight is fast, and by adjusting the formula ratio, it is ensured that the output backlight contains multi-band red light that is healthy for the human eye, such as bands with wavelengths of 620nm, 650nm, 670nm, etc., to achieve healthy eye protection.

[0055] In practical applications, the quantum dot light-emitting layer 4 can be prepared by a solution method, where the first quantum dot material 101 and the second quantum dot material 102 are dispersed in a polymer matrix, respectively. The polymer matrix forms a transparent base layer 100 corresponding to the quantum dot light-emitting layer 4 .

[0056] In some embodiments, in the quantum dot light-emitting layer 4, the proportion of the first quantum dot material 101 is greater than the proportion of the second quantum dot material 102. This design can enhance the proportion of red light with multiple bands in the backlight emitted by the backlight module, which helps to improve the eye protection effect on the human eye.

[0057] In some embodiments, as Figure 4 As shown, the quantum dot light-emitting layer 4 further includes red phosphor 103 , which can generate red light under the excitation of blue excitation light.

[0058] It can be understood that for traditional quantum film materials, the present invention can use the first quantum dot material 101 to selectively replace a portion of the red phosphor in the traditional quantum film material, and use the second quantum dot material 102 to completely replace the green phosphor in the traditional quantum film material. This makes the quantum dot light-emitting layer 4 of the embodiment of the present invention simultaneously contain the first quantum dot material 101, the second quantum dot material 102 and the red phosphor 103. Under the excitation of blue excitation light, it can be ensured that the light emitted by the quantum dot light-emitting layer 4 appears as white light because it contains blue excitation light, red light and green light. This white light can be used as the backlight of the display screen, and it is ensured that the backlight contains red light of the actual required band actually obtained by replacement, such as red light of the 620nm band and the 650nm band formed based on the first quantum dot material 101, so that the red light of the actual required band in the backlight is enhanced.

[0059] In some embodiments, as Figure 5 As shown, the excitation light source 3 is used to emit blue excitation light, and the quantum dot light-emitting layer 4 also includes red phosphor 103 and green phosphor 104. The red phosphor 103 can generate red light under the excitation of the blue excitation light, and the green phosphor 104 can generate green light under the excitation of the blue excitation light.

[0060] It can be understood that for traditional quantum film materials, the present invention can use the first quantum dot material 101 to selectively replace a portion of the red phosphor in the traditional quantum film material, and use the second quantum dot material 102 to selectively replace a portion of the green phosphor in the traditional quantum film material. This makes the quantum dot light-emitting layer 4 of the embodiment of the present invention simultaneously contain the first quantum dot material 101, the second quantum dot material 102, the red phosphor 103 and the green phosphor 104. Under the excitation of blue excitation light, it can be ensured that the light emitted by the quantum dot light-emitting layer 4 appears as white light because it contains blue excitation light, red light and green light. This white light can be used as the backlight of the display screen, and also contains multi-band red light that is healthy for the human eye, thereby achieving healthy eye protection.

[0061] In the second aspect, Figure 2 As shown, an embodiment of the present invention further provides a quantum dot light source, comprising the excitation light source 3 and the quantum dot light-emitting layer 4 as described above, wherein the quantum dot light-emitting layer 4 is provided at the light-emitting end of the excitation light source 3 .

[0062] It is understandable that, since the quantum dot light source is provided with the quantum dot light-emitting layer 4 , the design of the quantum dot light-emitting layer 4 can ensure that the light emitted by the quantum dot light source contains red light of at least two wavelength bands.

[0063] See also Figure 8 It can be seen that the luminescent film materials of traditional lamp beads use green quantum material (GQD) and red phosphor (KSF), while the quantum dot luminescent layer 4 of the quantum dot light source of the present invention uses a second quantum dot material, red phosphor (KSF) and a first quantum dot material (QD650), wherein the second quantum dot material corresponds to the green quantum material (GQD). That is to say, the present invention uses the first quantum dot material 101 to replace a part of the red phosphor in the traditional lamp beads, ensuring that the quantum dot light source outputs red light in multiple bands, and the red light intensity in the 650nm band is significantly enhanced.

[0064] In practical applications, the quantum dot material actually required in this embodiment can be first dispersed in a transparent resin (such as epoxy resin, silicone) to form a uniform quantum dot-resin mixture, and then the quantum dot-resin mixture can be evenly coated on the light-emitting end of the excitation light source 3 by spin coating, inkjet printing or screen printing to form a quantum dot light-emitting layer 4 at the light-emitting end of the excitation light source 3.

[0065] Furthermore, the quantum dot light source also includes a transparent protective layer, which is coated on the side of the quantum dot light-emitting layer 4 away from the light-emitting end. The transparent protective layer can be a silica coating or an aluminum oxide coating. The transparent protective layer can provide physical protection for the quantum dot light-emitting layer 4 and prevent the quantum dot material in the quantum dot light-emitting layer 4 from contacting the external environment.

[0066] In practical applications, the excitation light source 3 can be a blue LED chip, and COB (Chip on Board) or SMD (Surface Mount Device) packaging technology can be used to integrate the quantum dot light-emitting layer 4 and the transparent protective layer in sequence on the surface of the blue LED chip to complete the packaging of the blue LED chip.

[0067] In the third aspect, Figure 1 and Figure 2 As shown, an embodiment of the present invention further provides a display screen, comprising: a liquid crystal display layer 5 and the backlight module as described above; In the case where the quantum dot light-emitting layer 4 is disposed between the excitation light source 3 and the light guide layer 1 , the liquid crystal display layer 5 is disposed on the side of the light guide layer 1 facing away from the reflective layer 2 ; When the quantum dot light-emitting layer 4 is disposed on the side of the light-guiding layer 1 facing away from the reflective layer 2 , the liquid crystal display layer 5 is disposed on the side of the quantum dot light-emitting layer 4 facing away from the light-guiding layer 1 .

[0068] It can be understood that since the display screen includes a backlight module, the specific structure of the backlight module refers to the above embodiment. The display screen of this embodiment includes all the technical solutions of the above embodiment, and therefore has at least all the beneficial effects achieved by all the technical solutions of the above embodiment, which will not be repeated here.

[0069] Furthermore, the display screen further comprises a supporting layer 6, a light-gathering layer 7 and a transparent cover plate 8, as shown in FIG. Figure 1 As shown, for the case where the quantum dot light-emitting layer 4 is arranged on the side of the light-guiding layer 1 away from the reflective layer 2, the supporting layer 6 is arranged on the side of the reflective layer 2 away from the light-guiding layer 1, the focusing layer 7 is arranged between the liquid crystal display layer 5 and the quantum dot light-emitting layer 4, and the transparent cover plate 8 is arranged on the side of the liquid crystal display layer 5 away from the focusing layer 7.

[0070] Accordingly, if Figure 2 As shown, the quantum dot light-emitting layer 4 is disposed between the excitation light source 3 and the light-guiding layer 1. The excitation light source 3 and the quantum dot light-emitting layer 4 form a quantum dot light source. The support layer 6 is disposed on the side of the reflective layer 2 facing away from the light-guiding layer 1. The light-collecting layer 7 is disposed between the liquid crystal display layer 5 and the light-guiding layer 1. The transparent cover plate 8 is disposed on the side of the liquid crystal display layer 5 facing away from the light-collecting layer 7. Of course, the display screen of this embodiment may also be provided with a diffuser, which is located between the light-collecting layer 7 and the light-guiding layer 1.

[0071] The supporting layer 6 may be an iron frame to provide mounting support and support for the entire display screen, the focusing layer 7 may be a transparent prism, and the transparent cover plate 8 may be a transparent glass cover plate.

[0072] In a fourth aspect, an embodiment of the present invention further provides an electronic device, comprising: a housing and the display screen as described above, wherein the display screen is provided on the housing.

[0073] It is understandable that the electronic device may be a display device such as a learning machine or a tablet computer.

[0074] Since the electronic device includes a display screen, the specific structure of the display screen refers to the above embodiment. The electronic device of this embodiment includes all the technical solutions of the above embodiment, and therefore has at least all the beneficial effects achieved by all the technical solutions of the above embodiment, which will not be repeated here.

[0075] In some embodiments, the electronic device also includes: an ambient light sensor and a control module, the ambient light sensor is used to collect light intensity information of the environment in which the electronic device is located; the control module is electrically connected to the ambient light sensor and the excitation light source respectively, and the control module is used to control the luminous state of the excitation light source according to the light intensity information feedback from the ambient light sensor to adjust the luminous intensity of the backlight module.

[0076] It can be understood that in actual applications, based on the light intensity information fed back by the ambient light sensor, the control module can control the luminous state of the excitation light source. For example, by controlling the input current of the excitation light source, the luminous intensity of the excitation light source can be controlled to adjust the luminous intensity of the backlight module, thereby preventing the luminescence of the display screen from causing discomfort to the human eye and achieving the purpose of eye protection.

[0077] In practical applications, electrons in quantum materials transition to a high-energy state after being excited by light. When they return to the ground state, they release energy as light. Excitation light of different wavelengths (for example, blue excitation light) has different energies, which affects the degree of excitation and transition path of electrons in the quantum material, thereby affecting the wavelength of the resulting red light. Therefore, by controlling the input current of the excitation light source, the wavelength of the excitation light source can be controlled, thereby adjusting the red light emitted by the backlight unit.

[0078] Furthermore, in actual applications, the electronic device also includes: a timing module and a prompt module, which are respectively connected to the control module. The timing module is used to count the time the user uses the electronic device. When the time the user uses the electronic device is greater than the set threshold, the control module controls the prompt module to issue an information prompt and controls the display screen to enter the eye protection rest mode. For example, the control module automatically controls the brightness of the display screen according to the light intensity information feedback from the ambient light sensor, or controls the display screen to be in the screen-off state.

[0079] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A backlight module, characterized in that: include: A light guiding layer and a reflective layer, wherein the light guiding layer and the reflective layer are stacked; an excitation light source, configured to emit excitation light toward the light guiding layer; A quantum dot light-emitting layer is arranged between the excitation light source and the light-guiding layer, or on the side of the light-guiding layer away from the reflective layer. The quantum dot light-emitting layer includes at least two first quantum dot materials, and the at least two first quantum dot materials can generate red light of at least two bands under the excitation of the excitation light.

2. The backlight module according to claim 1, wherein: The excitation light source includes a blue light LED chip or an ultraviolet light LED chip.

3. The backlight module according to claim 1, wherein: The at least two first quantum dot materials can generate red light including a 620nm band and a 650nm band under the excitation of the excitation light.

4. The backlight module according to claim 3, wherein: The half-value width of at least one of the 620 nm band and the 650 nm band is 10-40 nm.

5. The backlight module according to claim 1, wherein: The excitation light source is used to emit blue excitation light; The quantum dot light-emitting layer further includes a second quantum dot material, which can generate green light under the excitation of the blue excitation light.

6. The backlight module according to claim 5, wherein: In the quantum dot light-emitting layer, the proportion of the first quantum dot material is greater than the proportion of the second quantum dot material; Alternatively, the quantum dot light-emitting layer further includes red phosphor, and the red phosphor can generate red light under the excitation of the blue excitation light.

7. The backlight module according to claim 1, wherein: The excitation light source is used to emit blue excitation light; The quantum dot light-emitting layer further includes red phosphor and green phosphor. The red phosphor can generate red light under the excitation of the blue excitation light, and the green phosphor can generate green light under the excitation of the blue excitation light.

8. The backlight module according to any one of claims 1 to 7, wherein: The first quantum dot material includes any one of cadmium selenide, a composite material of cadmium selenide and zinc sulfide, indium phosphide, perovskite and copper indium sulfide.

9. A quantum dot light source, characterized in that: It comprises the excitation light source and the quantum dot light-emitting layer according to any one of claims 1 to 8, wherein the quantum dot light-emitting layer is arranged at the light-emitting end of the excitation light source.

10. The quantum dot light source according to claim 9, characterized in that Also includes: A transparent protective layer is coated on a side of the quantum dot light-emitting layer away from the light-emitting end.

11. A display screen, characterized in that: include: A liquid crystal display layer and a backlight module according to any one of claims 1 to 8; In the case where the quantum dot light-emitting layer is provided between the excitation light source and the light guide layer, the liquid crystal display layer is provided on a side of the light guide layer away from the reflective layer; In a case where the quantum dot light-emitting layer is disposed on a side of the light-guiding layer away from the reflective layer, the liquid crystal display layer is disposed on a side of the quantum dot light-emitting layer away from the light-guiding layer.

12. An electronic device, characterized in that: include: A housing and a display screen as claimed in claim 11, wherein the display screen is arranged on the housing.

13. The electronic device according to claim 12, wherein: Also includes: An ambient light sensor, used to collect light intensity information of the environment in which the electronic device is located; The control module is electrically connected to the ambient light sensor and the excitation light source respectively, and is used to control the luminous state of the excitation light source according to the light intensity information fed back by the ambient light sensor to adjust the luminous intensity of the backlight module.

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