Patent Description:
Currently, for full-screen frameless products, in order to reserve space for the camera and the infrared sensor, it is necessary to perform laser hole-drilling treatment on the organic light-emitting diode (OLED) display panel. The laser hole-drilling treatment is a complicated process and is a process which would cause damage to a display substrate. Laser hole-drilling can cause undesirable effects such as edge cracks and thermal burns, resulting in reduced product reliability and reduced yield. Moreover, for the edge of the display panel hole-drilled with laser, design on thin film encapsulation is difficult and the encapsulation reliability is poor. Laser hole-drilling on panels with irregular shape has caused problems on OLED backplane circuit and thin film encapsulation (TFE). In summary, the laser hole-drilling in existing art to reserve space for the camera and the infrared sensor in the display product brought disadvantages such as great difficulty on thin film encapsulation, poor encapsulation reliability, and processing damage on the display panel.

<CIT> discloses an electronic device having a display. Inactive portions of the display such as peripheral portions of the display are masked using an opaque masking layer. An opening is provided in the opaque masking layer to allow light to pass. For example, a logo can be viewed through an opening in the opaque masking layer and a camera can receive light through an opening in the opaque masking layer. The display includes upper and lower polarizers, a color filter layer, and a thin-film transistor layer. The opaque masking layer is formed on the upper polarizer, is interposed between the upper polarizer and the color filter layer, or is interposed between the color filter layer and the thin-film transistor layer. The upper polarizer has unpolarized windows for cameras, logos, or other internal structures.

<CIT> discloses an electronic device having a display. Inactive portions of the display are masked using an opaque masking layer. An opening is provided in the masking layer. A camera receives light through the opening in the opaque masking layer. The display includes upper and lower polarizers, a color filter layer, and a thin-film transistor layer. The upper polarizer has an unpolarized window aligned with the opening in the opaque masking layer for the camera, a logo, or another internal structure. The unpolarized window is formed from openings in polarizer layers such as a polyvinyl alcohol layer and optical retarder layers. The openings passes through all or less than all of the polarizer layers. The openings is filled with transparent filler material. The polarizer includes a try-acetyl cellulose layer that continuously covers the opening in other polarizer layers.

<CIT> discloses an organic light emitting display device including a substrate, a gate insulation layer, a planarization layer, a boundary pattern, and a sub-pixel structure. The substrate includes a sub-pixel region and a transparent region. The gate insulation layer is disposed on the substrate. The planarization layer is disposed in the sub-pixel region on the gate insulation layer, and exposes the transparent region. The boundary pattern covers a boundary of the sub-pixel region and the transparent region. The sub-pixel structure is disposed on the planarization layer.

It is an objective of the present disclosure to provide a display panel, and display devices comprising the display panel.

The objective is achieved regarding the display panel by the features of independent claim <NUM>.

The display panel and display device according to the present invention have a high yield.

In order to clearly illustrate the technical solution of the invention, drawings will be briefly described in the following.

Embodiments of the present invention provide a display panel and a display device, in order to reduce process difficulty on thin film encapsulation of the display panel and improve reliability of the thin film encapsulation.

As illustrated in <FIG>, a display panel is provided. The display panel <NUM> includes: an array substrate <NUM> and a film layer structure <NUM> on the array substrate <NUM>. The array substrate <NUM> and the film layer structure <NUM> each have a transparent region <NUM>, and an orthographic projection of the transparent region of the array substrate is overlapped with an orthographic projection of the transparent region of the film layer structure in a direction perpendicular to the display panel.

The display panel includes at least one transparent region T and a display region <NUM> outside the at least one transparent region T. The plurality of pixels <NUM> are located in the display region D. A non-polarized radiation passes through the transparent region T of the display panel <NUM> without substantially polarized. The transparent regions <NUM> of the array substrate <NUM> and the film layer structure <NUM> are both located in the transparent region T of the display panel <NUM>.

The array substrate <NUM> includes a pixel structural layer <NUM> and an encapsulation layer <NUM> located on the pixel structural layer. The pixels <NUM> in the pixel structural layer are located outside the transparent region. An orthographic projection of the transparent region T on a plane P falls into an orthographic projection of the encapsulation layer on the plane P.

The transparent region T has a width at least <NUM> times larger than a distance between adjacent two pixels on the same side of the transparent region T in a direction parallel with the base substrate. Herein, the distance between two adjacent pixels can refer to a distance between their respective center positions.

In the display panel of <FIG>, the array substrate and the film layer structure each have a transparent region, and an orthographic projection of the transparent region of the array substrate is overlapped with an orthographic projection of the transparent region of the film layer structure in a direction perpendicular to the display panel. That is the display panel provided by the embodiment of the present disclosure has a transparent region, and the pixels in the pixel structural layer are disposed outside the transparent region. That is, opaque material in the pixel circuit of the pixel structural layer is disposed outside the transparent region, so that the encapsulation layer can completely cover the transparent region; therefore, when a display device includes the display panel, the camera and the infrared sensor can be disposed in a region corresponding to the transparent region if they are needed to be placed under the display panel. Laser hole-drill to the display panel is not needed, thus reducing the difficulty on thin film encapsulation during the preparation of the array substrate, improving the reliability of the thin film encapsulation, and avoiding processing damage such as edge cracks, thermal burns and the like caused by laser hole-drilling on the display panel.

Optionally, as illustrated in <FIG>, in the display panel, the array substrate <NUM> further includes a transparent substrate <NUM>, and the pixel structural layer <NUM> is located on the transparent substrate <NUM>.

Optionally, the array substrate and the film layer structure further have a display region, and the display region surrounds the transparent region. That is, as illustrated in <FIG>, the display panel <NUM> also has a transparent region T and a display region <NUM>. <FIG>, for example, can be a cross-sectional view taken along line A-A' in <FIG>.

The display panel can be, for example, an OLED display panel. When a pixel circuit in the pixel structural layer is fabricated onto the transparent substrate, any non-transparent material should avoid presenting in the transparent region, and light-emitting material to be subsequently evaporated is should also avoid presenting in the transparent region, so that the OLED pixels are outside the transparent region and the transparent region is not provided with any non-transparent material.

Optionally, a material of the transparent substrate includes at least one or a combination of the following: glass, polyimide (PI), and plastic. Of course, the transparent substrate can also be selected from other transparent materials, and can also be a flexible material or a non-flexible material.

Optionally, as illustrated in <FIG>, in the display panel, the encapsulation layer includes a first inorganic layer <NUM>, an organic layer <NUM> located on the first inorganic layer <NUM>, and a second inorganic layer <NUM> located on the organic layer <NUM>. For example, the OLED can be encapsulated by a TFE technology to form an encapsulation layer. The material of the first inorganic layer and the second inorganic layer include at least one or a combination of the following: silicon oxide, and silicon nitride; and the material of the organic layer includes polyacrylate.

It should be understood that the TFE technology is formed by alternatively stacking inorganic layers and organic layers, thereby effectively blocking moisture and oxygen from entering the OLED device, and avoiding corrosion of the OLED device by moisture and oxygen. In the encapsulation process, as illustrated in <FIG>, a corresponds to a width of an edge of the organic layer, b corresponds to a width of an edge of the inorganic layer, and c corresponds to a width of an edge of the transparent substrate. For the edge region of the display panel, the TFE process should ensure that a, b, and c in <FIG> have relatively large values. For example, a case that a sum of a, b, and c are in a range from <NUM> to <NUM> is satisfied, which allows the encapsulation layer to effectively protect the OLED device, that is, to ensure the reliability of the encapsulation layer.

If a laser-drilling process is performed on the display panel, as illustrated in <FIG>, that is, in <FIG>, an edge encapsulation condition needs to be satisfied in an edge region <NUM>; therefore, in the case that the pixel density is the same, a size of a reserved region <NUM> for laser-drilling is smaller than that of the transparent region <NUM> of the display panel as illustrated in <FIG>. In the case that the reserved region <NUM> for laser-drilling is the same size as the transparent region <NUM> as illustrated in <FIG>, more pixels are needed to be sacrificed for laser hole-drilling. That is, a pixel region of the display is larger than a pixel region of the display panel provided by laser-drilling, thereby increasing the pixel density of the display panel.

Optionally, in the display panel, the film layer structure includes a touch screen panel (TSP), a polarizer (POL), and a transparent cover. As illustrated in <FIG>, in the display panel, the film layer structure <NUM> includes a touch screen panel (TSP) <NUM> located on the array substrate <NUM>, a polarizer (POL) <NUM> located on the TSP <NUM>, and a transparent cover <NUM> located on the POL <NUM>.

Alternatively, the positions of the POL and TSP in <FIG> can be interchanged. As illustrated in <FIG>, a display panel includes a POL <NUM> located on the array substrate <NUM>, a TSP <NUM> located on the POL <NUM>, and a transparent cover <NUM> located on the TSP <NUM>.

Alternatively, the TSP <NUM> may also be disposed on the transparent cover <NUM>. A display panel structure is, for example, as illustrated in <FIG>. The film layer structure <NUM> includes a POL <NUM> located on the array substrate <NUM>, a transparent cover <NUM> located on the POL <NUM>, and a TSP <NUM> located on the transparent cover <NUM>.

The polarizer <NUM> in <FIG> has an opening <NUM>, an orthographic projection of the opening <NUM> is overlapped with an orthographic projection of the transparent region <NUM> of the film layer structure, in the direction perpendicular to the display panel.

In the display panel, a material of the transparent cover plate can be, for example, glass or other transparent materials.

It should be understood that, in the display panel, the TSP includes a touch electrode, and a material of the touch electrode can be a transparent material or a non-transparent material. In the case that the material of the touch electrode is a non-transparent material, which corresponds to the present invention, it is required to drill a hole in the step of fabricating the TSP, a hole-drilling region corresponds to the transparent region of the display region. Preferably, in the display panel, the touch screen panel includes a touch electrode, and a material of the touch electrode includes one or a combination of the following materials: indium tin oxide, and graphene. In this way, the touch screen panel is a transparent touch screen panel, hole drilling in the touch screen panel is not needed, and avoid presence of circuit in particular region is also not needed, which further simplifies the process of fabricating the display panel. In the TSPs in <FIG> , the materials of the touch electrodes are all transparent materials.

Optionally, the film layer structure as illustrated in <FIG> further includes an optical adhesive <NUM>. The optical adhesive <NUM> is in the same layer as the polarizer and fills in the opening of the polarizer. The optical adhesive can be, for example, optically clear adhesive (OCA), optically clear resin (OCR), or the like.

It should be understood that air can be filled in the opening of the POL <NUM>, or an optical adhesive can be provided in the opening of the POL <NUM>. Compared with the opening region filled with air, the opening of the polarizer <NUM> filled with the optical adhesive makes transition in refractive index of different media in the light transmitting region more uniform, so that in the case that the camera is disposed under the transparent region of the display panel, the shooting effect of the camera is better.

Optionally, the array substrate and the film layer structure each include a plurality of transparent regions. That is, the display panel also has a plurality of transparent regions. Alternatively, different transparent regions have different shapes. As illustrated in <FIG>, the display panel <NUM> has a circular transparent region <NUM> and an elliptical transparent region <NUM>. The circular transparent region <NUM> may have a diameter of <NUM>, the elliptical transparent region <NUM> may have a minor axis of <NUM>, and the elliptical transparent region <NUM> may have a major axis of <NUM> to <NUM>.

Optionally, as illustrated in <FIG>, the display panel further includes: a heat dissipation film <NUM> disposed under the array substrate <NUM>. The heat dissipation film <NUM> has an opening region corresponding to the transparent region in shape. The heat dissipation film can be, for example, a copper film or a graphite film.

A display device, includes the display panel described before, and a photographing device and a distance sensing device which are located under the display panel. An orthographic projection of the transparent region on a plane completely covers orthographic projections of the photographing device and the distance sensing device on the plane.

Optionally, the photographing device includes a camera, and the distance sensing device includes an infrared sensor.

For example, in the case that the display panel includes a transparent region as illustrated in <FIG>, an orthographic projection of the circular transparent region <NUM> on an upper surface of the device body <NUM> completely covers an orthographic projection of the camera on the device body <NUM>. An orthographic projection of the elliptical transparent region <NUM> on the upper surface of the device body <NUM> completely covers an orthographic projection of the infrared sensor on the upper surface of the device body <NUM>. In the case that the display device includes the display panel as illustrated in <FIG>, a structure of the display device is as illustrated in <FIG> (infrared sensor is not illustrated), the camera <NUM> is disposed on the device body <NUM>, and the display panel is located on the camera <NUM>.

Optionally, in the case that the transparent region is provided with a transparent substrate, an encapsulation layer and a touch screen panel, the camera has a color temperature parameter matched with a color temperature parameter of materials of the transparent substrate, the encapsulation layer, and the touch screen panel. In the case that the transparent region of the display panel is provided with a transparent substrate, an encapsulation layer, a TSP and other film layers, a material of the transparent substrate, the encapsulation layer the TSP and the like in the transparent region have an influence on the color temperature of the light passing through the transparent region; therefore, in order to ensure the photographing effect of the camera, the camera has a color temperature parameter matched with a color temperature parameter of the stacked film layer consisting of the transparent substrate, the encapsulation layer, the TSP and other materials. For example, in the case that the camera has a color temperature parameter of <NUM> Kelvin (K) and the stacked film layer has a color temperature parameter of <NUM>, the camera is needed to be adjusted to increase the color temperature of the camera, so that the camera can still meet the color temperature requirement of <NUM> when the color temperature parameter of the stacked film layer is <NUM>.

Optionally, the display device further includes an integrated circuit (IC) and a flexible printed circuit (FPC) which are connected to the display panel.

Claim 1:
A display panel (<NUM>), comprising:
a base substrate (<NUM>),
a plurality of pixels (<NUM>) located on the base substrate (<NUM>), and
at least one transparent region (T) and a display region (<NUM>) outside the at least one transparent region (T), the plurality of pixels (<NUM>) being located in the display region (<NUM>),
characterized by,
an thin film encapsulation layer (<NUM>) located on the plurality of pixels (<NUM>);
a touch screen panel (<NUM>), and a transparent cover (<NUM>) which are located on a side of the thin film encapsulation layer (<NUM>) opposite to the base substrate (<NUM>);
wherein, in a direction parallel with the base substrate (<NUM>), a width of the transparent region (T) is larger than a distance between adjacent two of the pixels (<NUM>) on a same side of the transparent region (T); and
wherein, in a plan view, the orthographic projection of the transparent region (T) on a plane in the direction perpendicular to the base substrate (<NUM>) falls into the orthographic projection of the thin film encapsulation layer (<NUM>) on the plane in the direction perpendicular to the base substrate (<NUM>), wherein the plane is parallel with the base substrate (<NUM>),
wherein the touch screen panel (<NUM>) comprises a touch electrode made of a non-transparent material, and the touch electrode is provided with a hole-drilling region corresponds to the transparent region of the display region.