Display panel based on biological identification technology, manufacturing method thereof and display device
阅读说明:本技术 基于生物识别技术的显示面板及其制造方法、显示装置 (Display panel based on biological identification technology, manufacturing method thereof and display device ) 是由 杜晓松 周文斌 郭丰 李高敏 孙剑 高裕弟 于 2020-06-18 设计创作,主要内容包括:本发明实施例公开了一种基于生物识别技术的显示面板及其制造方法、显示装置。显示面板包括驱动背板,驱动背板包括多个过孔和与多个过孔一一对应的多个焊盘;位于焊盘远离驱动背板一侧的多个像素,像素包括感测像素单元和发光显示像素单元;感测像素单元用于感测带有识别信息的信号光并输出感测信号;发光显示像素单元用于根据接收到的驱动背板的信号进行发光,发光显示像素接收到的信号与感测信号关联;其中,感测像素单元包括依次设置于焊盘上的保护层和图像传感层;保护层包括第一开口,第一开口暴露出部分焊盘以连通焊盘和图像传感层。本发明实施例的技术方案提升了显示面板的生物识别效果和显示效果,提高电子产品解锁的效率。(The embodiment of the invention discloses a display panel based on a biological recognition technology, a manufacturing method thereof and a display device. The display panel comprises a driving backboard, wherein the driving backboard comprises a plurality of through holes and a plurality of bonding pads in one-to-one correspondence with the through holes; the pixels are positioned on one side of the bonding pad, which is far away from the driving backboard, and comprise sensing pixel units and light-emitting display pixel units; the sensing pixel unit is used for sensing the signal light with the identification information and outputting a sensing signal; the light-emitting display pixel unit is used for emitting light according to the received signal for driving the backboard, and the signal received by the light-emitting display pixel is associated with the sensing signal; the sensing pixel unit comprises a protective layer and an image sensing layer which are sequentially arranged on the bonding pad; the protective layer includes a first opening exposing a portion of the pad to communicate the pad and the image sensing layer. The technical scheme of the embodiment of the invention improves the biological recognition effect and the display effect of the display panel and improves the unlocking efficiency of the electronic product.)
1. A display panel based on biometric identification technology, comprising:
the driving back plate comprises a plurality of through holes and a plurality of bonding pads in one-to-one correspondence with the through holes;
the plurality of pixels are positioned on one side of the bonding pad, which is far away from the driving backboard, and each pixel comprises a sensing pixel unit and a light-emitting display pixel unit; the sensing pixel unit is used for sensing the signal light with the identification information and outputting a sensing signal; the light-emitting display pixel unit is used for emitting light according to the received signal of the driving backboard, and the signal received by the light-emitting display pixel is associated with the sensing signal;
the sensing pixel unit comprises a protective layer and an image sensing layer which are sequentially arranged on the bonding pad; the protective layer includes a first opening exposing a portion of the pad to communicate the pad and the image sensing layer.
2. The biometric technology based display panel of claim 1, wherein the sensing pixel unit further comprises:
the first insulating layer is positioned on one side, far away from the driving back plate, of the image sensing layer and comprises a second opening, and the second opening exposes part of the image sensing layer; the projection of the first opening on the driving back plate is staggered with the projection of the second opening on the driving back plate;
and the sensing electrode is positioned on one side of the first insulating layer, which is far away from the driving back plate, and is in contact with the image sensing layer through the second opening.
3. The biometric technology-based display panel of claim 1, wherein the light-emitting display pixel unit comprises:
the pixel structure comprises a red sub-pixel unit, a green sub-pixel unit and a blue sub-pixel unit; the light emitting color of the light emitting layer in the red sub-pixel unit is red, the light emitting color of the light emitting layer in the green sub-pixel unit is green, and the light emitting color of the light emitting layer in the blue sub-pixel unit is blue;
each sub-pixel unit further comprises a first display electrode, a first semiconductor layer, a second semiconductor layer and a second display electrode; the first semiconductor layer is located on one side, away from the driving backboard, of the light emitting layer, the first display electrode is located on one side, away from the driving backboard, of the first semiconductor layer, the second semiconductor layer is located on one side, close to the driving backboard, of the light emitting layer, the second display electrode is located on one side, close to the driving backboard, of the second semiconductor layer, and the second display electrode is in contact with the bonding pad.
4. The biometric technology based display panel of claim 3, wherein the red, green, blue and sensing pixel cells are arranged in a checkerboard pattern;
red sub-pixel units in the four pixels are adjacently arranged and arranged in a field shape; green sub-pixel units in the four pixels are adjacently arranged and arranged in a field shape; blue sub-pixel units in the four pixels are adjacently arranged and arranged in a field shape; the sensing pixel units in the four pixels are adjacently arranged and arranged in a field shape.
5. The biometric technology-based display panel according to claim 4, further comprising:
the second insulating layer is positioned on one side, away from the driving backboard, of the sensing pixel unit and the light-emitting display pixel unit; the second insulating layer comprises a third opening, a fourth opening and a groove, the third opening exposes a part of the sensing electrode of the sensing pixel unit, and the fourth opening exposes a part of the first display electrode of the light-emitting display pixel unit; the vertical projection of the groove on the driving back plate is positioned between the vertical projections of the adjacent light-emitting display pixel units on the driving back plate.
6. The biometric technology-based display panel according to claim 5, further comprising: the common electrode is positioned on one side, far away from the driving back plate, of the second insulating layer, and covers the second insulating layer; the common electrode is in contact with the sensing electrode of the sensing pixel unit through the third opening, and is in contact with the first display electrode of the light-emitting display pixel unit through the fourth opening.
7. The biometric technology-based display panel according to claim 6, further comprising: the third insulating layer is positioned on one side, far away from the driving backboard, of the common electrode, and covers the common electrode.
8. The biometric technology based display panel of claim 7, wherein the sensing pixel unit further comprises a lens located on a side of the third insulating layer away from the driving backplane, a projection of the lens on the driving backplane at least partially coinciding with a projection of the image sensing layer on the driving backplane.
9. A display device based on biometric technology, comprising the biometric technology based display panel according to any one of claims 1 to 8.
10. The display device based on biometric technology according to claim 9, further comprising a prism unit for changing a propagation direction of light received and/or emitted by the display panel for human-computer interaction.
11. A method for preparing a display panel based on a biological recognition technology is characterized by comprising the following steps:
providing a driving back plate and a light-emitting display pixel unit substrate; the driving back plate comprises a plurality of through holes and a plurality of bonding pads in one-to-one correspondence with the through holes, and the light-emitting display pixel unit substrate comprises a plurality of light-emitting display pixel units;
respectively bonding the sub-pixel units with different colors with the driving backboard by adopting a mass transfer technology;
manufacturing sensing pixel units among the light-emitting display pixel units, wherein at least one light-emitting display pixel unit and at least one light-emitting display pixel unit form a pixel; the manufacturing of the sensing pixel unit comprises the steps of sequentially forming a protective layer, an image sensing layer and a sensing electrode on the bonding pad; the protective layer includes a first opening exposing a portion of the pad to communicate the pad and the image sensing layer.
Technical Field
The embodiment of the invention relates to the technical field of display, in particular to a display panel of a biological recognition technology, a preparation method of the display panel and a display device.
Background
With the continuous development of display technology, the application range of display panels is wider and wider, and the requirements of people on the display panels are higher and higher. For example, electronic products that are unlocked by biometric technology.
However, the existing display panel has the problem of poor biological recognition effect, the unlocking efficiency of the electronic product is reduced, and the user experience is influenced.
Disclosure of Invention
The embodiment of the invention provides a display panel based on a biological identification technology, a manufacturing method thereof and a display device, which are used for improving the biological identification effect and the display effect of the display panel and improving the unlocking efficiency of an electronic product.
In a first aspect, an embodiment of the present invention provides a display panel based on biometric technology, including:
the driving back plate comprises a plurality of through holes and a plurality of bonding pads in one-to-one correspondence with the through holes;
the plurality of pixels are positioned on one side of the bonding pad, which is far away from the driving backboard, and each pixel comprises a sensing pixel unit and a light-emitting display pixel unit; the sensing pixel unit is used for sensing the signal light with the identification information and outputting a sensing signal; the light-emitting display pixel unit is used for emitting light according to the received signal of the driving backboard, and the signal received by the light-emitting display pixel is associated with the sensing signal;
the sensing pixel unit comprises a protective layer and an image sensing layer which are sequentially arranged on the bonding pad; the protective layer includes a first opening exposing a portion of the pad to communicate the pad and the image sensing layer.
Optionally, the sensing pixel unit further includes:
the first insulating layer is positioned on one side, far away from the driving back plate, of the image sensing layer and comprises a second opening, and the second opening exposes part of the image sensing layer; the projection of the first opening on the driving back plate is staggered with the projection of the second opening on the driving back plate;
and the sensing electrode is positioned on one side of the first insulating layer, which is far away from the driving back plate, and is in contact with the image sensing layer through the second opening.
Optionally, the light-emitting display pixel unit includes:
the pixel structure comprises a red sub-pixel unit, a green sub-pixel unit and a blue sub-pixel unit; the light emitting color of the light emitting layer in the red sub-pixel unit is red, the light emitting color of the light emitting layer in the green sub-pixel unit is green, and the light emitting color of the light emitting layer in the blue sub-pixel unit is blue;
each sub-pixel unit further comprises a first display electrode, a first semiconductor layer, a second semiconductor layer and a second display electrode; the first semiconductor layer is located on one side, away from the driving backboard, of the light emitting layer, the first display electrode is located on one side, away from the driving backboard, of the first semiconductor layer, the second semiconductor layer is located on one side, close to the driving backboard, of the light emitting layer, the second display electrode is located on one side, close to the driving backboard, of the second semiconductor layer, and the second display electrode is in contact with the bonding pad.
Optionally, the red sub-pixel units, the green sub-pixel units, the blue sub-pixel units and the sensing pixel units are arranged in a shape of Chinese character 'tian';
red sub-pixel units in the four pixels are adjacently arranged and arranged in a field shape; green sub-pixel units in the four pixels are adjacently arranged and arranged in a field shape; blue sub-pixel units in the four pixels are adjacently arranged and arranged in a field shape; the sensing pixel units in the four pixels are adjacently arranged and arranged in a field shape.
Optionally, the display panel further includes:
the second insulating layer is positioned on one side, away from the driving backboard, of the sensing pixel unit and the light-emitting display pixel unit; the second insulating layer comprises a third opening, a fourth opening and a groove, the third opening exposes a part of the sensing electrode of the sensing pixel unit, and the fourth opening exposes a part of the first display electrode of the light-emitting display pixel unit; the vertical projection of the groove on the driving back plate is positioned between the vertical projections of the adjacent light-emitting display pixel units on the driving back plate.
Optionally, the display panel further includes: the common electrode is positioned on one side, far away from the driving back plate, of the second insulating layer, and covers the second insulating layer; the common electrode is in contact with the sensing electrode of the sensing pixel unit through the third opening, and is in contact with the first display electrode of the light-emitting display pixel unit through the fourth opening.
Optionally, the display panel further includes: the third insulating layer is positioned on one side, far away from the driving backboard, of the common electrode, and covers the common electrode.
Optionally, the sensing pixel unit further includes a lens, the lens is located on a side of the third insulating layer away from the driving backplane, and a projection of the lens on the driving backplane is at least partially overlapped with a projection of the image sensing layer on the driving backplane.
In a second aspect, an embodiment of the present invention provides a display device based on biometric technology, including the display panel based on biometric technology according to any one of the first aspect.
Optionally, the display device further includes a prism unit, and the prism unit is configured to change a propagation direction of light received and/or emitted by the display panel to perform human-computer interaction.
In a third aspect, an embodiment of the present invention provides a method for manufacturing a display panel based on a biometric identification technology, including:
providing a driving back plate and a light-emitting display pixel unit substrate; the driving back plate comprises a plurality of through holes and a plurality of bonding pads in one-to-one correspondence with the through holes, and the light-emitting display pixel unit substrate comprises a plurality of light-emitting display pixel units;
respectively bonding the sub-pixel units with different colors with the driving backboard by adopting a mass transfer technology;
manufacturing sensing pixel units among the light-emitting display pixel units, wherein at least one light-emitting display pixel unit and at least one light-emitting display pixel unit form a pixel; the manufacturing of the sensing pixel unit comprises the steps of sequentially forming a protective layer, an image sensing layer and a sensing electrode on the bonding pad; the protective layer includes a first opening exposing a portion of the pad to communicate the pad and the image sensing layer.
According to the display panel based on the biological identification technology, the side, away from the driving backboard, of the bonding pad is provided with the plurality of pixels, and the pixels comprise sensing pixel units and light-emitting display pixel units; the sensing pixel unit is used for sensing the signal light with the identification information and outputting a sensing signal; the light-emitting display pixel unit is used for emitting light according to the received signal for driving the backboard, and the signal received by the light-emitting display pixel is associated with the sensing signal; the sensing pixel unit comprises a protective layer and an image sensing layer which are sequentially arranged on the bonding pad; the protective layer includes a first opening exposing a portion of the pad to communicate the pad and the image sensing layer. According to the technical scheme provided by the embodiment of the invention, the sensing pixel unit senses the signal light with the identification information and outputs the sensing signal, and the sensing pixel unit blocks oxidation of water and oxygen to the bonding pad between the image sensing layer and the driving back plate through the protective layer, so that the accuracy of the sensing signal output by the sensing pixel unit is improved, the biological identification effect of the display panel is improved, and the unlocking efficiency of the electronic product is improved. And the signals received by the light-emitting display pixels are associated with the sensing signals, so that the accuracy of the sensing signals output by the sensing pixel units is improved, and the display effect of the display panel is also ensured.
Drawings
Fig. 1 is a schematic structural diagram of a display panel based on biometric identification technology according to an embodiment of the present invention;
FIG. 2 is a schematic structural diagram of another display panel based on biometric identification technology according to an embodiment of the present invention;
fig. 3 is a schematic top view of a display panel based on biometric identification technology according to an embodiment of the present invention;
FIG. 4 is a schematic structural diagram of another display panel based on biometric identification technology according to an embodiment of the present invention;
FIG. 5 is a schematic structural diagram of another display panel based on biometric identification technology according to an embodiment of the present invention;
FIG. 6 is a schematic structural diagram of a display device based on biometric identification technology according to an embodiment of the present invention;
FIG. 7 is a light path diagram of the display device shown in FIG. 6;
fig. 8 is a schematic flowchart of a method for manufacturing a display panel based on biometric identification technology according to an embodiment of the present invention;
fig. 9-10 are schematic structural diagrams of display panels formed at various steps of a method for manufacturing a display panel based on biometric identification technology according to an embodiment of the present invention;
fig. 11 is a schematic flow chart of another method for manufacturing a display panel based on biometric identification technology according to an embodiment of the present invention;
fig. 12-13 are schematic structural diagrams of a portion of a display panel formed in another method for manufacturing a display panel based on biometric identification technology according to an embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.
The embodiment of the invention provides a display panel based on a biological identification technology, and the display panel can be suitable for display equipment such as AR/VR and the like. The display panel may be an Organic Light-Emitting Diode (OLED) display panel, a Micro Light-Emitting Diode (Micro LED) display panel, a Quantum Dot Light-Emitting Diode (QLED) display panel, or the like.
Fig. 1 is a schematic structural diagram of a display panel based on biometric identification technology according to an embodiment of the present invention, and referring to fig. 1, the display panel includes:
the
A plurality of
The
Specifically, the
The
The identification information may include fingerprint information and/or iris information, and the display panel performs biometric identification for unlocking according to the fingerprint information or iris information. The signal light carrying the fingerprint information is emitted to the
The iris information comes from the eyeball, the
According to the technical scheme provided by the embodiment of the invention, the sensing pixel unit senses the signal light with the identification information and outputs the sensing signal, so that the biological identification effect of the display panel is favorably improved, and the unlocking efficiency of the electronic product is improved. And the sensing pixel unit blocks oxidation of water and oxygen to a bonding pad between the image sensing layer and the driving back plate through the protective layer, so that the accuracy of sensing signals output by the sensing pixel unit is improved, the biological recognition effect of the display panel is improved, and the unlocking efficiency of electronic products is improved. And the signals received by the light-emitting display pixels are associated with the sensing signals, so that the accuracy of the sensing signals output by the sensing pixel units is improved, and the display effect of the display panel is also ensured.
Optionally, fig. 2 is a schematic structural diagram of another display panel based on biometric technology according to an embodiment of the present invention, and referring to fig. 2, the sensing pixel unit further includes:
a first insulating
and a
Specifically, the side of the
Optionally, fig. 3 is a schematic top view of a display panel based on biometric identification technology according to an embodiment of the present invention, and referring to fig. 3 and in conjunction with fig. 2, the light-emitting
a red sub-pixel unit R, a green sub-pixel unit G and a blue sub-pixel unit B; the emission color of the
Wherein each sub-pixel unit further comprises a
Specifically, the light-emitting
Optionally, with reference to fig. 3, the red sub-pixel unit R, the green sub-pixel unit G, the blue sub-pixel unit B, and the sensing pixel unit S are arranged in a shape of a Chinese character 'tian';
red sub-pixel units R in the four pixels are adjacently arranged and arranged in a field shape; green sub-pixel units G in the four pixels are adjacently arranged and arranged in a field shape; blue sub-pixel units B in the four pixels are adjacently arranged and arranged in a field shape; the sensing pixel units S in the four pixels are adjacently arranged and arranged in a field shape.
Specifically, the red sub-pixel unit R, the green sub-pixel unit G, the blue sub-pixel unit B and the sensing pixel unit S are located on the same plane, the red sub-pixel unit R, the green sub-pixel unit G, the blue sub-pixel unit B and the sensing pixel unit S are arranged in a field shape, four sub-pixel units with the same color are arranged in a concentrated manner, and four sensing pixel units S are arranged in a concentrated manner. The field-shaped structure is in array arrangement, which is beneficial to the compactness of pixels and improves the display effect of the pixels. In the manufacturing process of the display panel, a bulk transfer technology may be adopted to place the sub-pixel units of different colors on the driving
Optionally, fig. 4 is a schematic structural diagram of another display panel based on biometric identification technology according to an embodiment of the present invention, and referring to fig. 4, the display panel further includes:
a second insulating
Specifically, the
Optionally, with continued reference to fig. 4, the display panel further includes: the
Specifically, the
Optionally, fig. 5 is a schematic structural diagram of another display panel based on biometric identification technology according to an embodiment of the present invention, and referring to fig. 5, the display panel further includes: and a third insulating
Optionally, with continued reference to fig. 5, the
Optionally, with continued reference to fig. 5, the display panel further includes a
The embodiment of the invention also provides a display device based on the biometric identification technology, which comprises the display panel based on the biometric identification technology in any embodiment.
Specifically, the display device may be, for example, AR glasses or VR glasses. The technical principle and the generated effect are similar, and the detailed description is omitted.
Optionally, fig. 6 is a schematic structural diagram of a display device based on a biometric technology according to an embodiment of the present invention, fig. 7 is a light path diagram of the display device shown in fig. 6, and referring to fig. 6-7, exemplarily, the display device in fig. 8 is an AR glasses, the display device further includes a prism unit 1, and the prism unit 1 is configured to change a propagation direction of light received and/or emitted by the display panel to perform human-computer interaction. The waveguide structure formed by the prism unit 1 can realize a 30-40 degree angle of view on glass within 3mm, and the thickness is thin and light, so that the waveguide structure can be combined with AR glasses. The AR glasses produced based on the AR optical structure have lighter and thinner volume, are closer to normal-vision glasses or sunglasses than AR glasses on the world in appearance, have larger angle of view of AR display pictures under the same volume, and have simple process and low cost.
The embodiment of the present invention further provides a method for manufacturing a display panel based on a biometric identification technology, fig. 8 is a schematic flow chart of the method for manufacturing a display panel based on a biometric identification technology according to the embodiment of the present invention, and fig. 9 to 11 are schematic structural diagrams of the display panel formed in each step by the method for manufacturing a display panel based on a biometric identification technology according to the embodiment of the present invention; referring to fig. 8-11, the method includes:
s110, providing a driving back plate and a light-emitting display pixel unit substrate; the driving backboard comprises a plurality of through holes and a plurality of bonding pads in one-to-one correspondence with the through holes, and the light-emitting display pixel unit substrate comprises a plurality of light-emitting display pixel units.
Specifically, referring to fig. 9, a driving
And S120, respectively bonding the sub-pixel units with different colors with the driving backboard by adopting a mass transfer technology.
Specifically, referring to fig. 10, the red sub-pixel unit, the green sub-pixel unit, and the blue sub-pixel unit are placed on the
S130, manufacturing sensing pixel units among the plurality of light-emitting display pixel units, wherein at least one light-emitting display pixel unit and at least one light-emitting display pixel unit form a pixel; the manufacturing method of the sensing pixel unit comprises the steps of forming a protective layer, an image sensing layer and a sensing electrode on a bonding pad in sequence; the protective layer includes a first opening exposing a portion of the pad to communicate the pad and the image sensing layer.
Specifically, referring to fig. 1, the
Fig. 11 is a schematic flow chart of a method for manufacturing another display panel based on biometric identification technology according to an embodiment of the present invention, and fig. 12 to 13 are schematic structural diagrams of a portion of the display panel formed in the method for manufacturing another display panel based on biometric identification technology according to an embodiment of the present invention, and referring to fig. 11 to 13, with reference to fig. 2, 4 and 5, the method includes:
s210, providing a driving back plate and a light-emitting display pixel unit substrate; the driving backboard comprises a plurality of through holes and a plurality of bonding pads in one-to-one correspondence with the through holes, and the light-emitting display pixel unit substrate comprises a plurality of light-emitting display pixel units.
And S220, respectively bonding the sub-pixel units with different colors with the driving backboard by adopting a mass transfer technology.
S230, manufacturing sensing pixel units among the plurality of light-emitting display pixel units, wherein at least one light-emitting display pixel unit and at least one light-emitting display pixel unit form a pixel; the manufacturing method of the sensing pixel unit comprises the steps of forming a protective layer, an image sensing layer and a sensing electrode on a bonding pad in sequence; the protective layer includes a first opening exposing a portion of the pad to communicate the pad and the image sensing layer.
It should be noted that steps S210 to S230 are identical to steps S110 to S130, and are not described herein again.
S240, sequentially forming a first insulating layer and a sensing electrode on one side, far away from the driving backboard, of the image sensing layer, wherein the first insulating layer comprises a second opening, and the second opening exposes part of the image sensing layer; the projection of the first opening on the driving back plate is staggered with the projection of the second opening on the driving back plate; the sensing electrode is in contact with the image sensing layer through the second opening.
Specifically, referring to fig. 2, the first insulating
S250, forming a second insulating layer on one side, away from the driving backboard, of the sensing pixel unit and the light-emitting display pixel unit; the second insulating layer comprises a third opening, a fourth opening and a groove, wherein the third opening exposes part of the sensing electrode of the sensing pixel unit, and the fourth opening exposes part of the first display electrode of the luminous display pixel unit; the vertical projection of the groove on the driving back plate is positioned between the vertical projections of the adjacent light-emitting display pixel units on the driving back plate.
Specifically, referring to fig. 12, the
S260, forming a common electrode on one side, far away from the driving back plate, of the second insulating layer, wherein the common electrode covers the second insulating layer; the common electrode is in contact with the sensing electrode of the sensing pixel unit through the third opening and in contact with the first display electrode of the light-emitting display pixel unit through the fourth opening.
Specifically, referring to fig. 4, the
And S270, forming a third insulating layer on one side of the common electrode, which is far away from the driving back plate, wherein the third insulating layer covers the common electrode.
Specifically, referring to fig. 13, a new groove is formed at a position where the
And S280, arranging a lens on one side of the third insulating layer far away from the driving backboard.
Specifically, referring to fig. 5, the
And S290, adhering a glass packaging layer to one side, far away from the driving back plate, of the third insulating layer through an adhesive layer.
Specifically, referring to fig. 5, the
It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.
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