CN107741671B - Display device and preparation method thereof - Google Patents

Abstract

The embodiment of the invention discloses a display device and a preparation method thereof. The display device includes: the display device comprises a display panel and a backlight unit, wherein the backlight unit comprises a plurality of micro light-emitting diodes; wherein, the micro light-emitting diodes are passive micro light-emitting diodes. Because the size of the micro light-emitting diode is very small, when the backlight unit is attached to the display panel, the requirement on the attachment precision is low; the plurality of micro light-emitting diodes adopt a passive driving mode, and the driving method is simple; moreover, compared with the backlight unit in the prior art, the thickness of the backlight unit with the micro light-emitting diodes is thinner, and the thickness of the whole display device is reduced.

Description

Display device and preparation method thereof

Technical Field

The embodiment of the invention relates to the technical field of display, in particular to a display device and a preparation method thereof.

Background

A Liquid Crystal Display (LCD), which belongs to a flat panel Display. With the development of technology, the LCD technology information products are also developed toward light, thin, short and small targets.

The LCD belongs to a passive light emitting device, and a backlight device is required to provide light for the LCD when the LCD performs light emitting display. In the prior art, after the LCD is prepared, the LCD and the backlight unit are generally bonded together by alignment bonding, and the alignment bonding precision requirement is high. Moreover, the backlight unit in the prior art has a relatively thick thickness, which results in a relatively thick final thickness of the LCD product, and does not meet the trend of thinning and lightening the LCD.

Disclosure of Invention

The invention provides a display device and a preparation method thereof, and aims to solve the technical problems that a backlight unit is thick and the requirement on bonding precision is high when the backlight unit is bonded with a display panel in the prior art.

In a first aspect, an embodiment of the present invention provides a display device, which includes a display panel and a backlight unit, where the backlight unit includes a plurality of micro light emitting diodes; wherein, the micro light-emitting diodes are passive micro light-emitting diodes.

In a second aspect, an embodiment of the present invention further provides a method for manufacturing a display device, where the method includes:

providing a display panel;

a backlight unit is provided, the backlight unit comprises a plurality of micro light emitting diodes, wherein the micro light emitting diodes are passive micro light emitting diodes.

The display device provided by the embodiment of the invention comprises a display panel and a backlight unit formed by a plurality of micro light-emitting diodes, wherein the micro light-emitting diodes have the size of micron level and are very small relative to the pixel pitch of dozens of micron levels, so that the micro light-emitting diodes are used as the backlight unit, and the requirement on the attaching precision can be reduced when the backlight unit is aligned and attached with the display panel; moreover, the plurality of micro light-emitting diodes in the backlight unit are passive micro light-emitting diodes, so that the driving mode of the micro light-emitting diodes is simple, the small thickness of the micro light-emitting diodes can be ensured, and the problems that the backlight unit in a display device such as a liquid crystal display in the prior art is thick and has high requirement on the attaching precision of the backlight unit are solved.

Drawings

Fig. 1 is a schematic top view of a display device according to an embodiment of the present invention;

fig. 2 is a schematic top view of another display device according to an embodiment of the present invention;

FIG. 3 is a schematic cross-sectional view of the display device shown in FIG. 2 along the section line A-A';

fig. 4 is a schematic top view of another display device according to an embodiment of the present invention;

FIG. 5 is a schematic cross-sectional view of the display device shown in FIG. 4 along the section line B-B';

fig. 6 is a schematic top view of another display device according to an embodiment of the present invention;

fig. 7 is a schematic top view of another display device according to an embodiment of the invention;

FIG. 8 is a schematic diagram illustrating a top view of another display device according to an embodiment of the present invention;

fig. 9 is a schematic top view of another display device according to an embodiment of the present invention;

fig. 10 is a schematic top view of another display device according to an embodiment of the present invention;

fig. 11 is a schematic top view of another display device according to an embodiment of the invention;

fig. 12 is a schematic top view of another display device according to an embodiment of the present invention;

fig. 13 is a schematic structural diagram of a micro light emitting diode according to an embodiment of the present invention;

fig. 14 is a schematic flow chart of a method for manufacturing a display device according to an embodiment of the present invention;

fig. 15-21 are schematic cross-sectional views illustrating various processes for fabricating a plurality of micro light emitting diodes on a side away from light emitted from a display panel 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 device, which comprises a display panel and a backlight unit, wherein the backlight unit comprises a plurality of micro light-emitting diodes, and the micro light-emitting diodes are passive micro light-emitting diodes. According to the technical scheme of the embodiment of the invention, the backlight unit formed by a plurality of micro light-emitting diodes is used as the backlight unit of the display panel, and the size of the micro light-emitting diodes is only in a micron level, so that the pixel pitch in the display panel in a dozen microns level is very small, therefore, when the backlight unit is aligned and attached with the display panel, the attaching precision of the display panel and the backlight unit can be reduced; moreover, the plurality of micro light-emitting diodes in the backlight unit are passive micro light-emitting diodes, and only corresponding potential signals need to be provided for electrodes of the micro light-emitting diodes when the micro light-emitting diodes are driven to emit light, so that the driving mode of the micro light-emitting diodes is simple, the small thickness of the micro light-emitting diodes can be ensured, and the technical problems that the backlight unit in a display device such as a liquid crystal display in the prior art is thick and the requirement on the attaching precision of the backlight unit is high are solved.

The above is the core idea of the present invention, and the technical solution in the embodiment of the present invention will be clearly and completely described below with reference to the drawings in the embodiment of the present invention. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without any creative work belong to the protection scope of the present invention.

Fig. 1 is a top view of a display device according to an embodiment of the present invention, and referring to fig. 1, the display device specifically includes:

adisplay panel 100 and abacklight unit 200, thebacklight unit 200 comprising a plurality of microlight emitting diodes 210; the microlight emitting diodes 210 are passive micro light emitting diodes.

Thebacklight unit 200 is disposed on a side of thedisplay panel 100 away from the light emitting area, and includes a plurality of microlight emitting diodes 210, and the microlight emitting diodes 210 are passive micro light emitting diodes, and referring to fig. 1, the passive micro light emitting diodes are arranged in an array. It can be understood that the passive micro light emitting diode is different from the active micro light emitting diode, and the passive micro light emitting diode only needs to input voltage signals of corresponding potentials to the cathode electrode and the anode electrode thereof in the light emitting process, and does not need to use a driving circuit including a thin film transistor and the like, so that the driving mode is simple.

Because the size of the micro light-emitting diode is only in the micron level and is very small relative to the pixel pitch of the dozens of microns, the micro light-emitting diode is used as a backlight unit, and the requirement on the attaching precision can be reduced when the backlight unit is aligned and attached with the display panel; moreover, the plurality of micro light-emitting diodes in the backlight unit are passive micro light-emitting diodes, so that the driving mode of the micro light-emitting diodes is simple, the small thickness of the micro light-emitting diodes can be ensured, and the problems that the backlight unit in a display device such as a liquid crystal display in the prior art is thick and has high requirement on the attaching precision of the backlight unit are solved.

With continued reference to fig. 1, thedisplay panel 100 may optionally include: abase substrate 110; a plurality ofpixel units 120 formed on thebase substrate 110; the vertical projection of at least a portion of thepixel unit 120 on thesubstrate 110 covers the vertical projection of themicro-light emitting diode 210 on thesubstrate 110. It should be noted that fig. 1 only exemplifies a case where the vertical projection of all thepixel units 120 on thesubstrate 110 covers the vertical projection of the microlight emitting diodes 210 on thesubstrate 110.

As shown in fig. 1, thebacklight unit 200 composed of the microlight emitting diodes 210 is used as the light source of thepixel unit 120, and the size of the microlight emitting diodes 210 is much smaller than that of thepixel unit 120, so that when thebacklight unit 200 is aligned and attached to thedisplay panel 100, only the vertical projection of thepixel unit 120 on thesubstrate 110 is required to cover the vertical projection of the microlight emitting diodes 210 on thesubstrate 110, and the alignment and attachment accuracy is low.

Optionally, the vertical projection of at least a part of thepixel units 120 on thesubstrate base 110 covers the vertical projection of the microlight emitting diodes 210 on thesubstrate base 110, which may be understood as that the vertical projection of a part of thepixel units 120 on thesubstrate base 110 covers the vertical projection of the microlight emitting diodes 210 on thesubstrate base 110, and may also be understood as that the vertical projection of a part of thepixel units 120 on thesubstrate base 110 covers the vertical projection of the microlight emitting diodes 210 on thesubstrate base 110, and the vertical projection of a part of thepixel units 120 on thesubstrate base 110 does not cover the vertical projection of the microlight emitting diodes 210 on thesubstrate base 110. The following description will be made separately for these two cases.

Fig. 2 is a top view of another display device according to an embodiment of the invention, fig. 3 is a schematic cross-sectional view of the display device shown in fig. 2 along a sectional line a-a', and referring to fig. 2 and fig. 3, apixel unit 120 may include adisplay area 121 and atransmission area 122; thedisplay region 121 includes afirst pixel electrode 1211, a firstcommon electrode 1212, and a firstthin film transistor 1213 connected to thefirst pixel electrode 1211; the vertical projection of thedisplay area 121 on thesubstrate base 110 covers the vertical projection of the microlight emitting diodes 210 on thesubstrate base 110.

For example, the display device provided in the embodiment of the present invention may be a liquid crystal display device, and the liquid crystal display device may include an array substrate, a color film substrate, and a liquid crystal layer (not shown in the figure) located between the array substrate and the color film substrate; an alignment film layer (not shown in the figure) is arranged on the array substrate and/or the color film substrate, and the alignment film layer is used for controlling the initial deflection direction of the liquid crystal layer. Alternatively, the Liquid Crystal layer may be a Polymer Dispersed Liquid Crystal (PDLC) layer, and the Polymer Dispersed Liquid Crystal film is a film material with excellent overall performance obtained by dispersing Liquid Crystal in a Polymer in the form of droplets. Wherein, the polymer is used as a membrane material to provide a stable network structure for the liquid crystal microdroplets; the liquid crystal molecules have strong optical anisotropy and dielectric anisotropy, so that the PDLC film is endowed with remarkable electrooptical characteristics, and the PDLC film becomes a novel light control film. The PDLC layer adopted by the liquid crystal layer can be used without a polaroid, so that the transmittance of the display device is increased.

Optionally, thefirst pixel unit 1211 in thedisplay area 121 may be located on the array substrate, the firstcommon electrode 1212 may be located on the color film substrate, and the liquid crystal layer is located between thefirst pixel unit 1211 and the firstcommon electrode 1212; or thefirst pixel unit 1211 and the firstcommon electrode 1212 are both located on the array substrate. The embodiment of the present invention does not limit the specific positional relationship between thefirst pixel electrode 1211 and the firstcommon electrode 1212. Alternatively, the firstcommon electrode 1212 may correspond to the plurality offirst pixel electrodes 1211, as shown in fig. 2; thefirst pixel electrode 1211 may correspond to only one block, and the embodiment of the invention is not limited to this. It is understood that, since thedisplay area 121 of thepixel unit 120 includes thefirst pixel electrode 1211, the firstcommon electrode 1212 and the firstthin film transistor 1213 connected to thefirst pixel electrode 1211, the liquid crystal layer corresponding to the portion of thedisplay area 121 can be normally deflected under the voltage driving of thefirst pixel electrode 1211 and the firstcommon electrode 1212, thedisplay area 121 can display normally, and the microlight emitting diode 210 covered by thedisplay area 121 can provide a light source for the normal display of thedisplay area 121. Thetransmissive region 122 of thepixel unit 120 is not provided with the electrode film layer and the driving circuit, so that the liquid crystal layer of thetransmissive region 122 maintains the initial deflection direction under the action of the initial alignment film layer, and the vertical projection of thetransmissive region 122 on thesubstrate 110 does not cover the vertical projection of the microlight emitting diode 210 on thesubstrate 100, so that the portion of thedisplay panel 100 corresponding to thetransmissive region 122 is transparent.

In addition, in all technical solutions provided by the present invention, the pixel electrode, the common electrode, and the substrate are made of transparent materials.

In the above scheme, thepixel unit 120 is configured to include thedisplay region 121 and thetransmissive region 122, thedisplay region 121 includes thefirst pixel electrode 1211, the firstcommon electrode 1212, and the firstthin film transistor 1213 connected to thefirst pixel electrode 1211, thetransmissive region 122 is not configured with any film layer, and since the size of the microlight emitting diode 210 is much smaller than that of thepixel unit 120, the microlight emitting diode 210 is only configured at a position corresponding to thelight emitting region 121 in thepixel unit 120, so that thedisplay region 121 in the display device can implement a display function, and thetransmissive region 122 can implement a transparent function, and finally implement a transparent display of the display device.

Fig. 4 is a schematic top view of another display device according to an embodiment of the invention, fig. 5 is a schematic cross-sectional view of the display device shown in fig. 4 along a sectional line B-B', and referring to fig. 4 and fig. 5, apixel unit 120 may include adisplay region 121 and atransmission region 122; thedisplay region 121 may include asecond pixel electrode 1231, a secondcommon electrode 1232, and a secondthin film transistor 1233 connected to thesecond pixel electrode 1231; thetransmissive region 122 includes athird pixel electrode 1241 and a thirdcommon electrode 1242, and thethird pixel electrode 1241 is disconnected from thesecond pixel electrode 1231; wherein, the vertical projection of thedisplay area 121 on thesubstrate 110 covers the vertical projection of the microlight emitting diode 210 on thesubstrate 110.

Since thedisplay area 121 of thepixel unit 120 includes thesecond pixel electrode 1231, the secondcommon electrode 1232, and the secondthin film transistor 1233 connected to thesecond pixel electrode 1231, the liquid crystal layer corresponding to the portion of thedisplay area 121 can be normally deflected under the voltage driving of thesecond pixel electrode 1231 and the secondcommon electrode 1232, thedisplay area 121 can display normally, and the microlight emitting diode 210 covered by thedisplay area 121 can provide a light source for the normal display of thedisplay area 121. Since thetransmissive region 122 of thepixel unit 120 includes only thethird pixel electrode 1241, the thirdcommon electrode 1242, and no thin film transistor connected to thethird pixel electrode 1241, and thethird pixel electrode 1241 is disconnected from thesecond pixel electrode 1231, the liquid crystal layer in thetransmissive region 122 maintains the initial deflection direction under the action of the initial alignment film layer, and the vertical projection of thetransmissive region 122 on thesubstrate 110 does not cover the vertical projection of the microlight emitting diode 210 on thesubstrate 110, so that the portion of thedisplay panel 100 corresponding to thetransmissive region 122 is transparent.

The above-mentioned scheme is to configure thepixel unit 120 to include thedisplay area 121 and thetransmissive area 122, thedisplay area 121 includes thesecond pixel electrode 1231, the secondcommon electrode 1232, and the secondthin film transistor 1233 connected to thesecond pixel electrode 1231, thetransmissive area 122 includes only thethird pixel electrode 1241, the thirdcommon electrode 1242, and does not include the thin film transistor connected to thethird pixel electrode 1241, and thethird pixel electrode 1241 is configured to be disconnected from thesecond pixel electrode 1231, and since the size of the microlight emitting diode 210 is much smaller than that of thepixel unit 120, in thepixel unit 120, the microlight emitting diode 210 is configured only at a position corresponding to thelight emitting area 121, so that thedisplay area 121 in the display device can implement a display function, thetransmissive area 122 can implement a transparent function, and finally implement a transparent display of the display device.

On the basis of the above scheme, optionally, as shown in fig. 2 and fig. 4, thedisplay panel 100 may further include a plurality ofscan lines 130 and a plurality ofdata lines 140, where the plurality ofscan lines 130 and the plurality ofdata lines 140 are insulated and crossed to define a plurality ofpixel units 120; the plurality ofdisplay regions 121 and the plurality oftransmissive regions 122 are arranged along the extending direction of thescan line 130; and thedisplay area 121 and thetransmissive area 122 are arranged at intervals along the extending direction of thedata line 140, as shown in fig. 2 and 4.

Optionally, fig. 6 is a schematic top view structure diagram of another display device provided in an embodiment of the present invention, and fig. 7 is a schematic top view structure diagram of another display device provided in an embodiment of the present invention, as shown in fig. 6 and 7, the plurality ofdisplay areas 121 and the plurality oftransmissive areas 122 may also be arranged along the extending direction of thedata line 140; and thedisplay area 121 and thetransmissive area 122 are arranged at intervals along the extending direction of thescan line 130. In the embodiment of the present invention, the positional relationship between thedisplay region 121 and thetransmissive region 122 in thesame pixel unit 120 is not limited.

Thedisplay areas 121 and thetransmissive areas 122 in thepixel units 120 are arranged at intervals, so that thedisplay areas 121 and thetransmissive areas 122 are uniformly distributed, and because thepixel units 120 are smaller, the distance between thedisplay areas 121 of every twopixel units 120 is also small, so that the display device ensures the continuity of a display picture when displaying the picture; similarly, the distance between thetransmissive regions 122 of every twopixel units 120 is also very small, so that when the display device performs transparent display, the continuity of the transparent picture is ensured, the transparency of the display device is realized, and finally, the uniform transparent display of the whole display device is realized. In addition, since thepixel unit 120 includes thedisplay area 121 and thetransmissive area 122, thetransmissive area 122 does not need to be provided with thin film transistors, thereby reducing the number of thin film transistors in the display device, increasing the aperture ratio of the transmissive area, improving the transmittance, and further increasing the transparent display performance of the display device.

Optionally, fig. 8 is a schematic top view structure diagram of another display device according to an embodiment of the present invention, and referring to fig. 8, a pixel unit includes a firsttype pixel unit 150 and a secondtype pixel unit 160. The first-type pixel unit 150 includes afourth pixel electrode 151, a fourthcommon electrode 152, and a thirdthin film transistor 153 connected to thefourth pixel electrode 151; wherein, the vertical projection of the first-type pixel unit 150 on thesubstrate 110 covers the vertical projection of the microlight emitting diode 210 on thesubstrate 110. The secondtype pixel unit 160 may include a transparent pixel electrode and a transparent common electrode disposed on thesubstrate base 110, as shown in fig. 8; it is also possible that any electrode film layer (not shown) is not included on thebase substrate 110.

The first-type pixel unit 150 includes afourth pixel electrode 151, a fourthcommon electrode 152, and a thirdthin film transistor 153 connected to thefourth pixel electrode 151, a portion of the liquid crystal layer corresponding to the first-type pixel unit 150 can be normally deflected under the voltage driving of thefourth pixel electrode 151 and the fourthcommon electrode 152, the first-type pixel unit 150 can normally perform display, and light emitted from the microlight emitting diode 210 covered by the first-type pixel unit 150 can provide a light source for the normal display of the first-type pixel unit 150. The secondtype pixel unit 160 is not provided with any electrode film layer, or only provided with an electrode film layer and not provided with a driving circuit, so that the liquid crystal layer corresponding to the secondtype pixel unit 160 maintains the initial deflection direction under the action of the initial alignment film layer, and when the vertical projection of the secondtype pixel unit 160 on the substrate does not cover the vertical projection of the microlight emitting diode 210 on thesubstrate 100, the portion of thedisplay panel 100 corresponding to the secondtype pixel unit 160 is transparent.

Optionally, the first-type pixel unit 150 may include afirst sub-pixel unit 1501, asecond sub-pixel unit 1502, and athird sub-pixel unit 1503, where thefirst sub-pixel unit 1501, thesecond sub-pixel unit 1502, thethird sub-pixel unit 1503, and the second-type pixel unit 160 may be arranged in a matrix of two rows and two columns, as shown in fig. 8; optionally, thefirst sub-pixel unit 1501, thesecond sub-pixel unit 1502, thethird sub-pixel unit 1503 and the second type ofpixel unit 160 may also be arranged in a row-by-four column matrix, as shown in fig. 9, and the specific arrangement relationship of thefirst sub-pixel unit 1501, thesecond sub-pixel unit 1502, thethird sub-pixel unit 1503 and the second type ofpixel unit 160 is not limited in the embodiment of the present invention.

It can be understood that, in the prior art, a liquid crystal display device generally includes a red light emitting unit, a green light emitting unit, and a blue light emitting unit, and light emitted by a backlight unit in the prior art is generally white light, and a color resistance layer is disposed on a color film substrate of the liquid crystal display device to ensure that light emitted by different light emitting units has different colors. In the embodiment of the invention, each micro light-emitting diode is independently used as the backlight source of the pixel unit, so that the technical effect of different light colors emitted by different light-emitting units can be realized by comprehensively setting the light-emitting colors and the color resistance layers of the micro light-emitting diodes. This will be specifically described below.

Optionally, fig. 10 is a schematic top view structure diagram of another display device according to an embodiment of the present invention, and as shown in fig. 10, the microlight emitting diode 210 may include a microred diode 211, a microgreen diode 212, and a microblue diode 213; wherein, the vertical projection of at least part of thepixel units 120 on thesubstrate base plate 110 covers the vertical projection of the microred diodes 211, the microgreen diodes 212 and the microblue diodes 213 on thesubstrate base plate 110. Fig. 10 is only illustrated by taking as an example that the vertical projection of thedisplay area 121 in thepixel unit 120 on thesubstrate 110 covers the vertical projection of the microred diode 211, the microgreen diode 212, and the microblue diode 213 on thesubstrate 110, respectively. As shown in fig. 10, the microred light diode 211, the microgreen light diode 212, and the micro bluelight diode 213 are respectively and independently arranged as the light sources of thedisplay regions 121 in thepixel unit 120, and because the microred light diode 211, the microgreen light diode 212, and the micro bluelight diode 213 can independently emit red light, green light, and blue light, a color resistance layer is not required to be arranged on the color film substrate, so that different colors of light emitted bydifferent display regions 121 can be ensured, and a film layer arrangement manner of the display device is simple.

Optionally, fig. 11 is a schematic top view structure diagram of another display device according to an embodiment of the present invention, and as shown in fig. 11, the color filter substrate may further include a color resistlayer 410, where the color resist layer includes a red color resistlayer 411, a green color resistlayer 412, and a blue color resistlayer 413; the microlight emitting diodes 210 include microwhite light diodes 214; the vertical projection of the red, green, and blue color resistlayers 411, 412, and 413 on thesubstrate base 110 covers the vertical projection of the microwhite light diodes 214 on thesubstrate base 110. Fig. 11 shows the color resistlayer 410 only by way of example, and only illustrates that the vertical projection of the color resistlayer 410 on thesubstrate 110 covers the vertical projection of thedisplay area 121 in thepixel unit 120 on thesubstrate 110. As shown in fig. 11, each of the microwhite light diodes 214 is independently used as a backlight source of thedisplay area 121, and is matched with the color resistlayer 410 on the color filter substrate to achieve the technical effect that the light colors emitted bydifferent display areas 121 are different.

The arrangement of the red color resistlayer 411, the green color resistlayer 412, and the blue color resistlayer 413 on the color filter substrate is not limited to the arrangement shown in fig. 11, and those skilled in the art can set the arrangement according to actual needs.

Fig. 12 is a schematic top view of another display device according to an embodiment of the invention. Referring to fig. 12, the color filter substrate includes a color resistlayer 410, and the color resistlayer 410 includes a red color resistlayer 411, a green color resistlayer 412, and a blue color resistlayer 413; the microlight emitting diode 210 includes a microred diode 211, a microgreen diode 212, and a microblue diode 213; the vertical projection of the red color resist 411 on thesubstrate base 110 covers the vertical projection of the micro red light-emittingdiodes 211 on thesubstrate base 110, the vertical projection of the green color resist 412 on thesubstrate base 110 covers the vertical projection of the micro green light-emittingdiodes 212 on thesubstrate base 110, and the vertical projection of the blue color resist 413 on thesubstrate base 110 covers the vertical projection of the micro blue light-emittingdiodes 213 on thesubstrate base 110. As shown in fig. 12, not only each of the microred diodes 211, the microgreen diodes 212, and the microblue diodes 213 is independently used as a backlight source of thedisplay area 121, but also the red color resistlayer 411, the green color resistlayer 412, and the blue color resistlayer 413 on the color filter substrate are matched to further ensure that the light colors emitted bydifferent display areas 121 are different.

Fig. 13 is a schematic structural diagram of a micro light emitting diode according to an embodiment of the present invention. Referring to fig. 13, optionally, the microlight emitting diode 210 includes a firstdriving electrode layer 215, a light emittingfunction layer 216, and a seconddriving electrode layer 217 sequentially stacked.

The firstdriving electrode layers 215 of the microlight emitting diodes 210 are all connected to a first power signal, and the seconddriving electrode layers 217 of the microlight emitting diodes 210 are all connected to a second driving signal. For example, the first driving signal may be a positive voltage signal, the second driving signal may be a negative driving signal, or the second driving electrode is grounded to drive the light emittingfunction layer 216 to emit light.

Optionally, the microlight emitting diode 210 further includes areflective layer 218 disposed on a side surface of the microlight emitting diode 210, wherein thereflective layer 218 is used to prevent light emitted from the microlight emitting diode 210 from exiting from the side surface.

Because the outer side of the micro light-emitting diode is surrounded by the reflecting layer, light can be gathered and directly irradiated into thepixel units 120, and color cross of twoadjacent pixel units 120 is avoided.

An embodiment of the present invention further provides a method for manufacturing a display device, where as shown in fig. 14, the method includes:

s110, providing a display panel.

And S120, providing a backlight unit, wherein the backlight unit comprises a plurality of micro light-emitting diodes, and the micro light-emitting diodes are passive micro light-emitting diodes.

According to the preparation method of the display device provided by the embodiment of the invention, the backlight unit comprising the plurality of micro light-emitting diodes is provided, and the micro light-emitting diodes are only in micron level and are very small relative to the pixel pitch of tens of micron level, so that the micro light-emitting diodes are used as the backlight unit, and the requirement on the attaching precision can be reduced when the backlight unit is aligned and attached with the display panel; moreover, the plurality of micro light-emitting diodes in the backlight unit are passive micro light-emitting diodes, so that the driving mode of the micro light-emitting diodes is simple, the small thickness of the micro light-emitting diodes can be ensured, and the problems that the backlight unit in a display device such as a liquid crystal display in the prior art is thick and has high requirement on the attaching precision of the backlight unit are solved.

Optionally, providing a display panel may include:

providing a substrate base plate;

preparing a plurality of pixel units on a substrate;

providing a backlight unit including a plurality of micro light emitting diodes may include:

and preparing a plurality of micro light-emitting diodes on the side far away from the light emitting side of the display panel, wherein the vertical projection of at least part of the pixel units on the substrate covers the vertical projection of the micro light-emitting diodes on the substrate.

Because the size of the micro light-emitting diode is far smaller than that of the pixel unit, when the backlight unit is aligned and attached with the display panel, only the vertical projection of the pixel unit on the substrate is required to cover the vertical projection of the micro light-emitting diode on the substrate, and the alignment and attachment precision requirement is low.

Optionally, preparing a plurality of micro light emitting diodes on the side far away from the light exit of the display panel may include sequentially preparing a first driving electrode on the side far away from the light exit of the display panel; preparing a light-emitting functional layer on one side of the first driving electrode, which is far away from the display panel; preparing a second driving electrode on one side of the micro light-emitting diode far away from the first driving electrode; the first driving electrode, the light-emitting functional layer and the second driving electrode form the micro light-emitting diode, and the first driving electrode and the second driving electrode are used for driving the light-emitting functional layer to emit light.

Optionally, preparing a plurality of micro light emitting diodes on the side far away from the light emitting of the display panel, and further sequentially preparing a first driving electrode on the side far away from the light emitting of the display panel; preparing a plurality of light-emitting functional layers on a bearing substrate; picking up a plurality of light-emitting functional layers from a carrier substrate by using a transfer head array; placing a plurality of light emitting functional layers on the first drive electrode; releasing a plurality of light emitting functional layers from the transfer head array; preparing a second driving electrode on one side of the light-emitting functional layer far away from the first driving electrode; the first driving electrode, the light-emitting functional layer and the second driving electrode form the micro light-emitting diode, and the first driving electrode and the second driving electrode are used for driving the light-emitting functional layer to emit light.

Specifically, fig. 15 to fig. 21 are schematic cross-sectional structural diagrams of respective processes for preparing a plurality of micro light emitting diodes on a side away from light exit of a display panel according to an embodiment of the present invention, and referring to fig. 15 to fig. 21, the preparation method specifically includes:

as shown in fig. 15, thefirst driving electrode 215 is prepared at a side far from the light emitted from thedisplay panel 100;

as shown in fig. 16, a plurality of light-emittingfunctional layers 216 are prepared on acarrier substrate 310;

as shown in fig. 17 and 18, the plurality of light-emittingfunctional layers 216 are picked up from thecarrier substrate 310 by thetransfer head array 320;

as shown in fig. 19, a plurality of light-emitting function layers 216 are disposed on thefirst drive electrode 215;

as shown in fig. 20, the plurality of light-emittingfunctional layers 216 are released from thetransfer head array 320;

as shown in fig. 21, thesecond drive electrode 217 is provided on the side of the light-emittingfunction layer 216 remote from thefirst drive electrode 215;

thefirst driving electrode 215, the light emittingfunction layer 216, and thesecond driving electrode 217 form the microlight emitting diode 210, and thefirst driving electrode 215 and thesecond driving electrode 217 are used to drive the light emittingfunction layer 216 to emit light.

By adopting the method for manufacturing the micro light-emitting diode as shown in fig. 15-21, the micro light-emitting diode is manufactured on the side of the display panel far away from the light-emitting surface in a transfer mode, the thickness of the display device is reduced, and the performance of the obtained micro light-emitting diode is reliable.

Optionally, in the preparation method of the display device provided in the embodiment of the present invention, providing a display panel may include:

providing a substrate base plate;

preparing a plurality of pixel units on a substrate;

providing a backlight unit including a plurality of micro light emitting diodes may include:

providing a micro light-emitting diode array, wherein the micro light-emitting diode array comprises a plurality of micro light-emitting diodes;

and aligning and attaching the light emitting side of the micro light emitting diode array and the side of the display panel far away from the light emitting side so as to enable the vertical projection of at least part of the pixel units on the plane where the micro light emitting diodes are located to cover the micro light emitting diodes, wherein the micro light emitting diodes are used for providing a light source for the pixel units. By adopting the preparation method of the display device, the micro light-emitting diode array and the side of the display panel far away from the light-emitting side are directly aligned and attached, and the size of the micro light-emitting diode is only in the micron level, so that the pixel pitch is very small compared with the pixel pitch in the tens of micron level, and the requirement on the attachment precision is low when the micro light-emitting diode array and the display panel are aligned and attached.

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 illustrated 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.

Claims (19)

1. A display device comprises a display panel and a backlight unit, wherein the backlight unit comprises a plurality of micro light-emitting diodes; wherein the plurality of micro light-emitting diodes are passive micro light-emitting diodes;

the display panel includes:

a substrate base plate;

a plurality of scanning lines, a plurality of data lines and a plurality of pixel units which are formed on the substrate, wherein the plurality of scanning lines and the plurality of data lines are insulated and crossed to define the plurality of pixel units;

the pixel unit comprises a display area and a transmission area, wherein the vertical projection of the display area on the substrate covers the vertical projection of the micro light-emitting diode on the substrate, the vertical projection of the transmission area on the substrate does not cover the vertical projection of the micro light-emitting diode on the substrate, and the liquid crystal layer of the transmission area keeps the initial deflection direction under the action of the initial alignment film layer to realize transparent display; the vertical projection of the transmission area on the substrate base plate is not overlapped with the vertical projection of the scanning line and the data line on the substrate base plate;

or the pixel units comprise a first type of pixel unit and a second type of pixel unit; the vertical projection of the first pixel unit on the substrate covers the vertical projection of the micro light-emitting diode on the substrate, the vertical projection of the second pixel unit on the substrate does not cover the vertical projection of the micro light-emitting diode on the substrate, and the vertical projection of the second pixel unit on the substrate does not overlap with the vertical projection of the scanning line and the data line on the substrate.

2. The display device according to claim 1, wherein the pixel unit includes a display region and a transmissive region;

the display area comprises a first pixel electrode, a first common electrode and a first thin film transistor connected with the first pixel electrode;

the vertical projection of the display area on the substrate covers the vertical projection of the micro light-emitting diode on the substrate.

3. The display device according to claim 1, wherein the pixel unit includes a display region and a transmissive region;

the display area comprises a second pixel electrode, a second common electrode and a second thin film transistor connected with the second pixel electrode;

the transmission area comprises a third pixel electrode and a third common electrode, and the third pixel electrode is disconnected from the second pixel electrode;

wherein the vertical projection of the display area on the substrate covers the vertical projection of the micro light emitting diode on the substrate.

4. The display device according to claim 1, wherein the pixel units include a first type of pixel unit and a second type of pixel unit;

the first-class pixel unit comprises a fourth pixel electrode, a fourth common electrode and a third thin film transistor connected with the fourth pixel electrode.

5. The display device according to any one of claims 1 to 4, wherein the display device comprises an array substrate, a color film substrate, and a liquid crystal layer located between the array substrate and the color film substrate;

and an alignment film layer is arranged on the array substrate and/or the color film substrate and is used for controlling the initial deflection direction of the liquid crystal layer.

6. The display device according to claim 2 or 3, wherein a plurality of the display regions and a plurality of the transmissive regions are arranged along the scanning line extending direction; and along the extending direction of the data line, the display area and the transmission area are arranged at intervals;

or, the plurality of display areas and the plurality of transmissive areas are arranged along the extending direction of the data line; and along the extending direction of the scanning line, the display area and the transmission area are arranged at intervals.

7. The display device according to claim 4, wherein the first pixel unit comprises a first sub-pixel unit, a second sub-pixel unit and a third sub-pixel unit;

the first sub-pixel unit, the second sub-pixel unit, the third sub-pixel unit and the second type of pixel units are arranged in a matrix of two rows and two columns.

8. The display device according to claim 1, wherein the micro light emitting diodes comprise micro red diodes, micro green diodes, and micro blue diodes;

wherein the vertical projection of at least part of the pixel units on the substrate covers the vertical projection of the micro red diodes, the micro green diodes and the micro blue diodes on the substrate.

9. The display device according to claim 5, wherein the color filter substrate further comprises a color resist layer, and the color resist layer comprises a red color resist layer, a green color resist layer, and a blue color resist layer;

the micro light emitting diode comprises a micro white light diode;

the vertical projection of the red color resistance layer, the green color resistance layer and the blue color resistance layer on the substrate covers the vertical projection of the miniature white light emitting diode on the substrate.

10. The display device according to claim 5, wherein the color filter substrate further comprises a color resist layer, and the color resist layer comprises a red color resist layer, a green color resist layer, and a blue color resist layer;

the micro light-emitting diode comprises a micro red light diode, a micro green light diode and a micro blue light diode;

the vertical projection of the red color resistance layer on the substrate covers the vertical projection of the micro red light-emitting diode on the substrate, the vertical projection of the green color resistance layer on the substrate covers the vertical projection of the micro green light-emitting diode on the substrate, and the vertical projection of the blue color resistance layer on the substrate covers the vertical projection of the micro blue light-emitting diode on the substrate.

11. The display device according to claim 1, wherein the micro light emitting diode comprises a first driving electrode layer, a light emitting function layer, and a second driving electrode layer, which are sequentially stacked.

12. The display device according to claim 11, wherein the first driving electrode layers of the micro light emitting diodes are all connected to a first power signal, and the second driving electrode layers of the micro light emitting diodes are all connected to a second driving signal.

13. The display device according to claim 11, wherein the micro light-emitting diode further comprises a reflective layer on a side surface of the micro light-emitting diode, the reflective layer being configured to prevent light emitted from the micro light-emitting diode from exiting from the side surface.

14. The display device according to claim 5, wherein the liquid crystal layer is a polymer dispersed liquid crystal layer.

15. A method of manufacturing a display device, comprising:

providing a display panel;

providing a backlight unit, wherein the backlight unit comprises a plurality of micro light-emitting diodes, and the micro light-emitting diodes are passive micro light-emitting diodes;

wherein, provide a display panel, include:

providing a substrate base plate;

preparing a plurality of scanning lines and a plurality of data lines and a plurality of pixel units on the substrate, wherein the plurality of scanning lines and the plurality of data lines are insulated and crossed to define the plurality of pixel units;

the pixel unit comprises a display area and a transmission area, wherein the vertical projection of the display area on the substrate covers the vertical projection of the micro light-emitting diode on the substrate, the vertical projection of the transmission area on the substrate does not cover the vertical projection of the micro light-emitting diode on the substrate, and the liquid crystal layer of the transmission area keeps the initial deflection direction under the action of the initial alignment film layer to realize transparent display; the vertical projection of the transmission area on the substrate base plate is not overlapped with the vertical projection of the scanning line and the data line on the substrate base plate;

or the pixel units comprise a first type of pixel unit and a second type of pixel unit; the vertical projection of the first pixel unit on the substrate covers the vertical projection of the micro light-emitting diode on the substrate, the vertical projection of the second pixel unit on the substrate does not cover the vertical projection of the micro light-emitting diode on the substrate, and the vertical projection of the second pixel unit on the substrate does not overlap with the vertical projection of the scanning line and the data line on the substrate.

16. The method of claim 15, wherein providing a backlight unit comprising a plurality of micro light emitting diodes comprises:

and preparing a plurality of micro light-emitting diodes on the side far away from the light emitting side of the display panel.

17. The method of claim 16, wherein fabricating a plurality of micro light emitting diodes on a side of the display panel away from the light emitting side of the display panel comprises:

preparing a first driving electrode at one side far away from the light emitting side of the display panel;

preparing a light-emitting functional layer on one side of the first driving electrode, which is far away from the display panel;

preparing a second driving electrode on one side of the micro light-emitting diode far away from the first driving electrode;

the first driving electrode, the light-emitting functional layer and the second driving electrode form the micro light-emitting diode, and the first driving electrode and the second driving electrode are used for driving the light-emitting functional layer to emit light.

18. The method of claim 16, wherein fabricating a plurality of micro light emitting diodes on a side of the display panel away from the light emitting side of the display panel comprises:

preparing a first driving electrode at one side far away from the light emitting side of the display panel;

preparing a plurality of light-emitting functional layers on a bearing substrate;

picking up a plurality of light-emitting functional layers from the carrier substrate by using a transfer head array;

placing the plurality of light emitting functional layers on the first driving electrode;

releasing the plurality of light emitting functional layers from the transfer head array;

preparing a second driving electrode on one side of the light-emitting functional layer far away from the first driving electrode;

the first driving electrode, the light-emitting functional layer and the second driving electrode form the micro light-emitting diode, and the first driving electrode and the second driving electrode are used for driving the light-emitting functional layer to emit light.

19. The method of claim 15, wherein providing a backlight unit comprising a plurality of micro light emitting diodes comprises:

providing a micro light-emitting diode array, wherein the micro light-emitting diode array comprises a plurality of micro light-emitting diodes;

and aligning and laminating the light emitting side of the micro light emitting diode array and the side of the display panel far away from the light emitting side, wherein the micro light emitting diode is used for providing a light source for the pixel unit.

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