WO2017206515A1 - 背光源及其制造方法和用途、显示装置 - Google Patents

背光源及其制造方法和用途、显示装置 Download PDF

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Publication number
WO2017206515A1
WO2017206515A1 PCT/CN2017/070634 CN2017070634W WO2017206515A1 WO 2017206515 A1 WO2017206515 A1 WO 2017206515A1 CN 2017070634 W CN2017070634 W CN 2017070634W WO 2017206515 A1 WO2017206515 A1 WO 2017206515A1
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Prior art keywords
light
infrared
guide plate
light guide
backlight
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PCT/CN2017/070634
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English (en)
French (fr)
Inventor
董瑞君
陈东
孙海威
王晨如
吴建杰
陈丽莉
Original Assignee
京东方科技集团股份有限公司
北京京东方光电科技有限公司
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Application filed by 京东方科技集团股份有限公司, 北京京东方光电科技有限公司 filed Critical 京东方科技集团股份有限公司
Priority to US15/545,317 priority Critical patent/US10539735B2/en
Publication of WO2017206515A1 publication Critical patent/WO2017206515A1/zh

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    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133602—Direct backlight
    • G02F1/133603—Direct backlight with LEDs
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
    • G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
    • G02B6/0066—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form characterised by the light source being coupled to the light guide
    • G02B6/0073—Light emitting diode [LED]
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133615—Edge-illuminating devices, i.e. illuminating from the side
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F21/00—Security arrangements for protecting computers, components thereof, programs or data against unauthorised activity
    • G06F21/30—Authentication, i.e. establishing the identity or authorisation of security principals
    • G06F21/31—User authentication
    • G06F21/32—User authentication using biometric data, e.g. fingerprints, iris scans or voiceprints
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
    • G06V10/00—Arrangements for image or video recognition or understanding
    • G06V10/10—Image acquisition
    • G06V10/12—Details of acquisition arrangements; Constructional details thereof
    • G06V10/14—Optical characteristics of the device performing the acquisition or on the illumination arrangements
    • G06V10/143—Sensing or illuminating at different wavelengths
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
    • G06V40/00—Recognition of biometric, human-related or animal-related patterns in image or video data
    • G06V40/10—Human or animal bodies, e.g. vehicle occupants or pedestrians; Body parts, e.g. hands
    • G06V40/12—Fingerprints or palmprints
    • G06V40/13—Sensors therefor
    • G06V40/1318—Sensors therefor using electro-optical elements or layers, e.g. electroluminescent sensing
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
    • G06V40/00—Recognition of biometric, human-related or animal-related patterns in image or video data
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    • G06V40/19—Sensors therefor
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
    • G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
    • G02B6/0033—Means for improving the coupling-out of light from the light guide
    • G02B6/005—Means for improving the coupling-out of light from the light guide provided by one optical element, or plurality thereof, placed on the light output side of the light guide
    • G02B6/0055—Reflecting element, sheet or layer
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
    • G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
    • G02B6/0065—Manufacturing aspects; Material aspects
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
    • G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
    • G02B6/0066—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form characterised by the light source being coupled to the light guide
    • G02B6/0068—Arrangements of plural sources, e.g. multi-colour light sources
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/13338—Input devices, e.g. touch panels
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133614—Illuminating devices using photoluminescence, e.g. phosphors illuminated by UV or blue light
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F2203/00—Function characteristic
    • G02F2203/11—Function characteristic involving infrared radiation
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/011—Arrangements for interaction with the human body, e.g. for user immersion in virtual reality
    • G06F3/013—Eye tracking input arrangements
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
    • G06V40/00—Recognition of biometric, human-related or animal-related patterns in image or video data
    • G06V40/10—Human or animal bodies, e.g. vehicle occupants or pedestrians; Body parts, e.g. hands
    • G06V40/12—Fingerprints or palmprints

Definitions

  • Embodiments of the present invention relate to a backlight, a method of fabricating the same, and use, and a display device including such a backlight.
  • an independent infrared LED is mainly used as a transmitter, together with an infrared receiver (CMOS shown in FIG. 1) as an independent infrared detection.
  • CMOS infrared receiver
  • the module works as shown in Figure 1.
  • such detectors can only be surface mounted (SMT) independently.
  • SMT surface mounted
  • the present invention is directed to solving at least one of the problems in the prior art.
  • a backlight source includes an LED light source that emits visible light, a light guide plate having a light incident surface and a light exiting surface, and a side where the light incident surface is located is a light incident side of the light guide plate.
  • Infrared quantum dot wherein the LED light source is provided
  • the infrared quantum dot is disposed on at least one surface of the light guide plate to be capable of receiving part of visible light emitted by the LED light source and emitting infrared light.
  • the infrared quantum dots are disposed on at least one of the light-receiving surface and the light-emitting surface of the light guide plate.
  • the infrared quantum dots are disposed on a partial region of the light incident surface and the light exit surface of the light guide plate.
  • the light guide plate is a side-entry light guide plate, and the infrared quantum dot is disposed on a side of the light guide plate opposite to the light incident side.
  • the backlight further includes a plastic frame, and a reflective layer is disposed on an inner surface of the plastic frame facing the light guide plate for transmitting visible light and/or infrared light from the light guide plate. Reflected back to the light guide plate.
  • the infrared quantum dots emit infrared light having a wavelength of 950 nm.
  • the infrared quantum dots have a size smaller than a thickness of the light guide plate.
  • the exterior of the infrared quantum dot is coated with a layer of quantum dot protection.
  • a method of manufacturing a backlight comprising:
  • the infrared quantum dots are uniformly mixed in the photo-curing glue
  • the infrared quantum dot mixed with the infrared quantum dots is dropped onto at least one face of the light guide plate.
  • the infrared quantum dots mixed with the infrared quantum dots are dropped onto at least one of the light-receiving surface and the light-emitting surface of the light guide plate.
  • the method further comprises the step of coating a layer of quantum dot protection on the exterior of the cured product after the infrared quantum dot droplets are cured.
  • the infrared quantum dots have a size smaller than a thickness of the light guide plate.
  • a display device comprising the backlight of any of the above embodiments.
  • the backlight according to any of the above embodiments, wherein the backlight is applied to infrared fingerprint recognition and/or infrared eye tracking.
  • FIG. 1 is a schematic diagram showing the operation of an existing backlight infrared detector module
  • FIG. 2 is a schematic diagram of a backlight structure in accordance with an embodiment of the present invention.
  • FIG. 3 shows a right side view of the backlight structure of FIG. 2, wherein the quantum dot protection layer of FIG. 2 is removed for the purpose of illustrating infrared quantum dots;
  • FIG. 4 is a flow chart of a method of fabricating a backlight in accordance with an embodiment of the present invention.
  • Quantum dots are quasi-zero-dimensional nanomaterials with a regular crystal-like arrangement of atoms. Since quantum dots have a high specific surface area and a suitable band gap width, they are considered to be an ideal photoluminescent material.
  • the invention utilizes the characteristics of quantum dots, and uses infrared quantum dots to convert a part of visible light emitted by the LED light source into infrared light, thereby eliminating the need to provide separate Infrared light emitters, and no need to set up a separate power supply for the infrared emitter, and it converts the visible light that may have been dissipated into infrared light, thus greatly reducing system power consumption and improving light utilization.
  • a backlight including an LED light source that emits visible light, a light guide plate, and an infrared quantum dot, wherein the LED light source is disposed on a light incident surface of the light guide plate The infrared quantum dot is disposed on at least one surface of the light guide plate. And the infrared quantum dot is excited by a part of the visible light emitted by the LED light source to emit infrared light, and another part of the visible light emitted by the LED light source and the infrared light are uniformly emitted through the light emitting surface of the light guide plate.
  • the backlight 1 includes a light guide plate 2, a prism sheet 4, a reflection sheet 6, and a light emitting diode (LED) 10 as a light source.
  • FIG. 2 also schematically shows that the backlight 1 comprises a plastic frame 12, and only a part of the plastic frame is shown in FIG. 2, and a reflection is provided on the inner surface of the plastic frame (ie, one side of the light guide plate 2).
  • the layer 14 is configured to reflect visible light and/or infrared light emitted from the light guide plate 2 back to the light guide plate 2.
  • the light guide plate 2 has a light incident surface 22 for light incidence and a light exit surface 26 for light emission, and the LED light source 10 is disposed on the light incident surface 22 side of the light guide plate 2 to emit visible light.
  • the infrared quantum dot 20 may be disposed on at least one of the light-receiving plate 2 and the light-receiving surface and the light-emitting surface.
  • the infrared quantum dot 20 is excited by a part of visible light emitted from the LED light source 10 to emit infrared light, and then another portion of the visible light emitted from the LED light source 10 is emitted together with the infrared light through the light exit surface 26 of the light guide plate 2.
  • the emitted visible light is used for image display of the display device, and the emitted infrared light is used in conjunction with an infrared receiver in the display device for infrared light applications such as infrared eye tracking and infrared fingerprint recognition.
  • the LED light source 10 is disposed on one side of the light guide plate 2 (ie, the left side 22 shown in FIG. 2), that is, the backlight 1 shown in FIG. 2 is a side-entry backlight.
  • the source, LED light source 10 is disposed on the light incident surface 22 side of the light guide plate 2.
  • the infrared quantum dot 20 is disposed on a surface 24 of the light guide plate 2 opposite to the light incident surface 22.
  • a part of the visible light emitted by the LED light source 10 is not incident on the infrared quantum dot 20, and this portion can be The light is still emitted as visible light from the light exit surface 26; at the same time, another portion of the visible light emitted by the LED light source 10 is incident on the infrared quantum dot 20, and the infrared quantum dot 20 is excited by the other portion of the visible light to emit infrared light, and then the LED light source A portion of the visible light emitted by the 10 is emitted together with the infrared light through the light exit surface 26 of the light guide plate 2.
  • the visible light L1, L2 emitted from the LED light source 10 is irradiated onto the surface 24 opposite to the light incident surface 22, and the visible light L3 is irradiated onto the reflective sheet 6. Since the infrared quantum dots 20 are spaced apart on the surface 24, the visible light L1 is not incident on the infrared quantum dots 20, which is reflected by the reflective layer 14 on the plastic frame 12 and then directed toward the reflective sheet 6 through the light guide plate 2; and the visible light L2 is incident.
  • the infrared quantum dot 20 is excited by the visible light L2 to emit infrared light, and then the infrared light is reflected by the reflective layer 14 on the plastic frame 12, and then is incident on the reflective sheet 6 through the light guide plate 2, and finally, through the reflective sheet 6.
  • visible light L1, L2, and L3 become visible light L1', infrared light L2', and visible light L3' are emitted from the light-emitting surface 26 of the light guide plate 2.
  • the infrared light is emitted only from the infrared emitter, and in the backlight of the embodiment of the invention, the infrared light can be uniformly emitted from the entire light emitting surface, Conducive to the application of infrared eye tracking and infrared fingerprint recognition.
  • the infrared quantum dot 20 is shown on one surface opposite to the LED light source in FIG. 2, in other embodiments, the infrared quantum dot 20 may be disposed on the light incident surface and/or the light exit surface. At least part of the area.
  • the outer portion of the infrared quantum dot 20 is coated with a quantum dot protection layer 202 to prevent the infrared quantum dot 20 from being ineffective after being eroded by water or oxygen.
  • the infrared quantum dot 20 has a circular cross section. According to one embodiment, the diameter of the infrared quantum dot 20 is smaller than the thickness T of the light guide plate 2. In this way, it is possible to ensure that the infrared quantum dots 20 are not destroyed by water or oxygen. Although four infrared quantum dots 20 are shown in FIG. 3, Practical applications require setting a greater or lesser number of quantum dots. Although the infrared quantum dots 20 are shown as being circular in FIG. 3, the infrared quantum dots may not necessarily be circular, in which case, optionally, the overall size of the infrared quantum dots 20 is smaller than the thickness T of the light guide plate 2. .
  • the infrared quantum dot 20 emits a wavelength of Infrared light of about 950 nm.
  • an embodiment of the present invention further provides a method of manufacturing the backlight 1 as described above. As shown in FIG. 4, the method may include the following steps:
  • the LED light source 10 emitting visible light is assembled on the light incident surface side of the light guide plate 2 of the backlight 1;
  • step S2 the infrared quantum dots mixed with the infrared quantum dots 20 are dropped onto at least one of the light-receiving surface and the light-emitting surface of the light guide plate 2.
  • step S1 the LED light source 10 is assembled on the light incident surface 22 side of the light guide plate 2, and in step S2, the infrared quantum dots mixed with the infrared quantum dots 20 are dropped onto the guide.
  • the surface of the light panel 2 opposite the light entrance surface 22 is on a surface 24.
  • the method may further comprise the following steps:
  • a layer of quantum dot protection layer 202 is coated on the outside of the cured product.
  • the diameter of the infrared quantum dot 20 is smaller than the thickness T of the light guide plate 2.
  • an embodiment of the present invention also provides a display device including the backlight 1 as described above.
  • the display device further includes an infrared receiver.
  • an infrared receiver In the backlight 1 described above, a part of visible light emitted by the LED light source 10 is guided together with infrared light.
  • the light-emitting surface 26 of the light plate 2 is emitted, and the emitted visible light is used for image display of the display device, and the emitted infrared light is reflected by the eyeball or the finger and received by the infrared receiver, thereby realizing infrared eye tracking or infrared fingerprint recognition.
  • the backlight 1 as described above can be applied to infrared fingerprint recognition and/or infrared eye tracking.
  • the visible light source of the backlight is directly used to excite the infrared quantum dots to emit infrared light, and a separate infrared emitter is not required, which can further improve the integration of the backlight structure and reduce system power consumption. At the same time, the assembly process is also reduced.
  • infrared light can be uniformly emitted from the entire light-emitting surface of the light guide plate, which is advantageous for applications such as infrared eye tracking and infrared fingerprint recognition.

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Abstract

一种背光源（1）及其显示装置，包括发射可见光的LED光源（10）、导光板（2）和红外量子点（20），其中， LED光源（10）设置在导光板（2）的入光侧，红外量子点（20）设置在导光板（2）的至少一个面上。红外量子点（20）受LED光源（10）发出的可见光的一部分激发后发出红外光， LED光源（10）发出的可见光的另一部分和红外光一起经由导光板（2）的出光面（26）均匀射出。还公开了一种具有红外量子点（20）的背光源（1）的制造方法和用途。

Description

背光源及其制造方法和用途、显示装置
相关申请的交叉引用
本申请要求2016年6月3号提交中国专利局的申请号为201610390035.X的中国专利申请的优先权，其全部内容通过引用合并于本申请中。
技术领域
本发明的实施例涉及一种背光源及其制造方法和用途、以及包括这种背光源的显示装置。
背景技术
目前，大多数显示装置都是通过背光源结构照射液晶显示屏来实现图像显示。而且，随着技术的发展，例如红外指纹识别、红外眼球追踪等各种新技术开始逐渐应用于显示装置中，因此，需要设置能够射出红外光的光源。
而在现有的采用红外指纹识别、红外眼球追踪等技术的光源中，主要使用独立的红外LED作为发射器，与红外接收器(图1中所示的CMOS)一起，作为一个独立的红外探测器模块，其工作原理如图1所示。而且此种探测器只可独立进行表面贴装(SMT)。这种结构的集成度不高，而且需要设置单独的红外光源，增加了系统的功耗，此外，还需要进行单独的组装，增加了制造工序。
发明内容
本发明旨在解决现有技术中存在的至少一个问题。
根据本发明的一个方面，提供一种背光源，包括发射可见光的LED光源；导光板，该导光板具有入光面和出光面，所述入光面所在的一侧为导光板的入光侧；红外量子点；其中，所述LED光源设 置在所述导光板的入光侧，所述红外量子点设置在所述导光板的至少一个面上，以能够接受LED光源发出的部分可见光，并发出红外光。
在一个实施例中，所述红外量子点设置在所述导光板的除入光面和出光面以外的至少一个面上。
在一个实施例中，所述红外量子点设置在所述导光板的入光面和出光面的部分区域上。
在一个实施例中，所述导光板为侧入式导光板，所述红外量子点设置在所述导光板的与入光侧相对的一侧上。
在一个实施例中，所述背光源还包括胶框，在所述胶框面向所述导光板的内表面上设置有反射层，用于将从所述导光板射出的可见光和/或红外光反射回所述导光板。
在一个实施例中，所述红外量子点发出的红外光的波长为950nm。
在一个实施例中，所述红外量子点的尺寸小于所述导光板的厚度。
在一个实施例中，所述红外量子点的外部涂覆有一层量子点保护层。
根据本发明的另一方面，提供一种制造背光源的方法，该方法包括：
将发射可见光的LED光源组装在背光源的导光板的入光面上；
将红外量子点均匀混合于光固胶中；
将混合有红外量子点的红外量子点液滴滴至所述导光板的至少一个面上。
在一个实施例中，将混合有红外量子点的红外量子点液滴至所述导光板的除入光面和出光面以外的至少一个面上。
进一步地，所述方法还包括如下步骤：在红外量子点液滴固化后，在固化物的外部涂覆一层量子点保护层。
在一个实施例中，所述红外量子点的尺寸小于所述导光板的厚度。
根据本发明的又一方面，还提供一种显示装置，包括根据上述实施例中任一项所述的背光源。
根据本发明的再一方面，还提供一种根据上述实施例中任一项所述的背光源的用途，其中将上述背光源应用于红外指纹识别和/或红外眼球追踪。
通过下文中参照附图对本发明所作的描述，本发明的其它目的和优点将显而易见，并可帮助对本发明有全面的理解。
附图说明
图1示出了现有的背光源中红外探测器模块的工作原理图；
图2是根据本发明的实施例的背光源结构的示意图；
图3示出了图2的背光源结构的右侧视图，其中为了示出红外量子点，图2中的量子点保护层被移除；以及
图4是制造根据本发明的实施例的背光源的方法的流程图。
具体实施方式
下面通过实施例，并结合附图，对本发明的技术方案作进一步具体的说明。在说明书中，相同或相似的附图标号指示相同或相似的部件。下述参照附图对本发明实施方式的说明旨在对本发明的总体发明构思进行解释，而不应当理解为对本发明的一种限制。
另外，在下面的详细描述中，为便于解释，阐述了许多具体的细节以提供对本披露实施例的全面理解。然而明显地，一个或多个实施例在没有这些具体细节的情况下也可以被实施。在其他情况下，公知的结构和装置以图示的方式体现以简化附图。
量子点是准零维纳米材料，且具有类似晶体的规整原子排列。由于量子点有较高的比表面积、适当的带隙宽度，因此它被认为是一种理想的光致发光材料。本发明利用量子点的特性，使用红外量子点将LED光源发出的一部分可见光转换为红外光，从而无需设置单独的 红外光发射器，并且无需设置用于红外发射器的单独的电源，并且其是将原先可能耗散掉的可见光转换为红外光，因此极大地降低了系统功耗，提高了光的利用率。
根据本发明的总体技术构思的一个方面，提供一种背光源，该背光源包括发射可见光的LED光源、导光板和红外量子点，其中，所述LED光源设置在所述导光板的入光面上，所述红外量子点设置在所述导光板的至少一个面上。并且所述红外量子点受所述LED光源发出的可见光的一部分激发后发出红外光，所述LED光源发出的可见光的另一部分和所述红外光一起经由所述导光板的出光面均匀射出。
图2是根据本发明的实施例的背光源结构的示意图，如图2所示，背光源1包括导光板2、棱镜片4、反射片6和作为光源的发光二极管(LED)10。而且，图2中还示意性地示出背光源1包括胶框12，图2中仅示出了胶框的一部分，在胶框的内表面(即面向导光板2的一面)上设置有反射层14，用于将从导光板2射出的可见光和/或红外光反射回导光板2。导光板2具有用于光入射的入光面22和用于光出射的出光面26，LED光源10设置在导光板2的入光面22侧，发射可见光。在本公开的实施例中，为了产生红外光，可以将红外量子点20设置在导光板2的除入光面和出光面以外的至少一个面上。这样，红外量子点20受LED光源10发出的可见光的一部分激发后发出红外光，然后LED光源10发出的可见光的另一部分和所述红外光一起经由导光板2的出光面26射出。本领域技术人员可以理解的是，射出的可见光用于显示装置的图像显示，射出的红外光用于与显示装置中的红外接收器配合用于例如红外眼球追踪和红外指纹识别等红外光应用。
在图2示出的实施例中，LED光源10设置在导光板2的一侧(即图2中所示的左侧22)，即，图2中示出的背光源1为侧入式背光源，LED光源10设置在导光板2的入光面22侧。红外量子点20设置在导光板2的与入光面22相对的一个表面24上。这样，LED光源10发出的可见光的一部分不会入射至红外量子点20，这部分可 见光仍作为可见光从出光面26射出；同时，LED光源10发出的可见光的另一部分会入射至红外量子点20，此时红外量子点20受这另一部分可见光激发后发出红外光，然后LED光源10发出的可见光的一部分和所述红外光一起经由导光板2的出光面26射出。
下面，以LED光源10发出的三束可见光L1、L2、L3为例说明从LED光源10发出的光线的不同传播路径。如图2所示，LED光源10发出的可见光L1、L2照射至与入光面22相对的表面24，而可见光L3照射至反射片6上。由于在表面24上间隔设置有红外量子点20，所以可见光L1未入射至红外量子点20，其经胶框12上的反射层14反射后经导光板2射向反射片6；而可见光L2入射至红外量子点20，红外量子点20受可见光L2激发后发出红外光，然后该红外光经胶框12上的反射层14反射后经导光板2射向反射片6，最后，通过反射片6的反射，可见光L1、L2、L3分别变为可见光L1’、红外光L2’、可见光L3’从导光板2的出光面26射出。由此可见，本发明的实施例中仅将原先可能耗散掉的一部分可见光转换为红外光，并且无需设置单独的红外发射器电源，因此极大地降低了系统功耗。并且，在现有的利用单独的红外发射器的背光源中，红外光仅从红外发射器一点射出，而在本发明实施例的背光源中，红外光可以从整个出光面均匀地射出，有利于红外眼球追踪和红外指纹识别等技术的应用。
应理解的是，虽然图2中示出红外量子点20设置在与LED光源相对的一个表面上，但是在其它实施例中，红外量子点20也可以设置在入光面和/或出光面上的至少部分区域上。
可选地，如图2所示，红外量子点20的外部涂覆有一层量子点保护层202，以防止红外量子点20被水、氧侵蚀后失效。
图3示出了图2的背光源结构的右侧视图，其中为了示出红外量子点20，图2中的量子点保护层202被移除。如图3所示，红外量子点20的横截面为圆形。根据一个实施例，红外量子点20的直径小于导光板2的厚度T。这样，能够确保红外量子点20不被水、氧侵蚀而失效。虽然在图3中示出了4个红外量子点20，但是可以根据 实际应用的需要设置更多或更少数量的量子点。虽然在图3中示出了红外量子点20为圆形，但是红外量子点可以不必为圆形，在这种情况下，可选地，红外量子点20的整体尺寸小于导光板2的厚度T。
在图2的实施例中，红外光从导光板2的出光面26射出后，还需要通过液晶面板(图中未示出)而射出，而液晶面板对红外光的透过率约为18％～30％，根据面板的分辨率和尺寸不同而有所差异，而红外光波段中透过率最高的为波长约950nm的红外光，所以，在一个实施例中，红外量子点20发出波长为约950nm的红外光。
另外，本发明的实施例还提供一种制造如上所述的背光源1的方法，如图4所示，该方法可以包括如下步骤：
S1.将发射可见光的LED光源10组装在背光源1的导光板2的入光面侧；
S2.将红外量子点20均匀混合于液体光固胶中；
S3.将混合有红外量子点20的红外量子点液滴滴至导光板2的至少一个面上。
在一个实施例中，在步骤S2中，将混合有红外量子点20的红外量子点液滴滴至导光板2的除入光面和出光面以外的至少一个面上。
在另一个实施例中，在步骤S1中，将LED光源10组装在导光板2的入光面22侧，并且在步骤S2中，将混合有红外量子点20的红外量子点液滴滴至导光板2的与入光面22相对的一个表面24上。
根据一个实施例，所述方法还可以包括如下步骤：
S4.在含有红外量子点的红外量子点液滴固化后，在固化物外部涂覆一层量子点保护层202。
在一个实施例中，所述红外量子点20的直径小于导光板2的厚度T。
此外，本发明的实施例还提供一种显示装置，其包括如上所述的背光源1。
在一个示例的实施例中，显示装置还包括红外接收器。在上述背光源1中，LED光源10发出的可见光的一部分和红外光一起经由导 光板2的出光面26射出，并且射出的可见光用于显示装置的图像显示，射出的红外光经眼球或手指反射后被红外接收器接收，从而实现红外眼球追踪或红外指纹识别。
进一步地，如上所述的背光源1可以被应用于红外指纹识别和/或红外眼球追踪中。
根据本发明的各实施例，直接使用背光源的可见光源对红外量子点进行激发而发出红外光，无需设置单独的红外发射器，能够进一步提高背光源结构的集成度，并且降低系统功耗，同时还减少了组装工序。并且在本发明的背光源中，红外光可以从导光板的整个出光面均匀地射出，有利于红外眼球追踪和红外指纹识别等技术的应用。
在上述各实施例中，以侧入式背光源作为示例描述和图示了本发明的构思，本领域技术人员应理解的是，在不背离本总体发明构思的原则和精神的情况下，本发明的技术构思可以应用于其它类型和/或结构的背光源中。
虽然结合附图对本发明进行了说明，但是附图中公开的实施例旨在对本发明的实施方式进行示例性说明，而不能理解为对本发明的一种限制。
虽然本发明总体构思的一些实施例已被显示和说明，本领域普通技术人员将理解，在不背离本总体发明构思的原则和精神的情况下，可对这些实施例做出改变，本发明的范围以权利要求和它们的等同物限定。

Claims (13)

  1. 一种背光源，包括：
    发射可见光的LED光源；
    导光板，该导光板具有入光面和出光面，所述入光面所在的一侧为导光板的入光侧；
    红外量子点；
    其中，所述LED光源设置在所述导光板的入光侧，所述红外量子点设置在所述导光板的至少一个面上，以能够接受LED光源发出的部分可见光，并发出红外光。
  2. 根据权利要求1所述的背光源，其中，所述红外量子点设置在所述导光板的除入光面和出光面以外的至少一个面上。
  3. 根据权利要求1所述的背光源，其中，所述红外量子点设置在所述导光板的入光面和出光面的部分区域上。
  4. 根据权利要求1或2所述的背光源，其中，所述导光板为侧入式导光板，所述红外量子点设置在所述导光板的与入光侧相对的一侧上。
  5. 根据权利要求1-4中任一项所述的背光源，其中，所述背光源还包括胶框，在所述胶框面向所述导光板的内表面上设置有反射层，用于将从所述导光板射出的可见光和/或红外光反射回所述导光板。
  6. 根据权利要求1-5中任一项所述的背光源，其中，所述红外量子点发出的红外光的波长为950nm。
  7. 根据权利要求4所述的背光源，其中，所述红外量子点的尺寸小于所述导光板的厚度。
  8. 根据权利要求1-7中任一项所述的背光源，其中，所述红外量子点的外部涂覆有一层量子点保护层。
  9. 一种制造背光源的方法，该方法包括：
    将发射可见光的LED光源组装在背光源的导光板的入光侧上；
    将红外量子点混合于光固胶中；
    将混合有红外量子点的红外量子点液滴滴至所述导光板的至少一个面上。
  10. 根据权利要求9所述的方法，还包括：
    在红外量子点液滴固化后，在固化物的外部涂覆一层量子点保护层。
  11. 根据权利要求9所述的方法，其中，所述红外量子点的尺寸小于所述导光板的厚度。
  12. 一种显示装置，包括根据权利要求1-8中任一项所述的背光源。
  13. 一种根据权利要求1-8中任一项所述的背光源的用途，其中，将所述背光源应用于红外指纹识别和/或红外眼球追踪。
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