WO2021032274A1

WO2021032274A1 - Display stack for electronic device

Info

Publication number: WO2021032274A1
Application number: PCT/EP2019/072097
Authority: WO
Inventors: Jouni Tapio MÄKI; Sami MAATTANEN
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2019-08-19
Filing date: 2019-08-19
Publication date: 2021-02-25

Abstract

A display stack (1) for an electronic device (2) comprising a display arrangement comprising a plurality of adjoining layers and a support structure (6) comprising a support plate (6a). The layers comprise at least a cover layer (3), at least one adhesive layer (4), and a display panel (5). A main surface of the support plate (6a) is fixed to a main surface of the display panel (5) by means of the adhesive layer(s) (4). The display stack may be thinner than prior art, due to fewer necessary layers.

Description

DISPLAY STACK FOR ELECTRONIC DEVICE

TECHNICAL FIELD The disclosure relates to a display stack for an electronic device comprising a display arrangement, comprising a plurality of adjoining layers, and a support structure.

BACKGROUND The size of electronic devices, such as tablets and mobile phones, is an important consideration when designing electronic devices. There is movement towards very large displays which cover as much as possible of the electronic device, making the space available for other components very limited. Electronic devices may, e.g., be provided with actuators in order to generate audio and haptic waves by vibrating other components of the electronic device, i.e. components other than speakers, microphones etc. This reduces the number of components such that the space available for other components is increased. The vibrating components of the electronic device are, in other words, used as receiver and loudspeaker, and oftentimes includes the display stack. Hence, the display stack has to have high mechanical stiffness in order to withstand the stresses applied onto it due to the vibrations, and make the electronic device sufficiently durable.

Furthermore, prior art display stacks comprise a relatively large number of layers, some of which are relatively stiff in order to achieve sufficient audio quality and sufficient stability. The large number of layers adds to the volume of the display stack. SUMMARY

It is an object to provide an improved display stack. The foregoing and other objects are achieved by the features of the independent claims. Further implementation forms are apparent from the dependent claims, the description, and the figures.

According to a first aspect, there is provided a display stack for an electronic device comprising a display arrangement comprising a plurality of adjoining layers, the layers comprising at least a cover layer, at least one adhesive layer, and a display panel, a support structure comprising a support plate, a main surface of the support plate being fixed to a main surface of the display panel by means of the adhesive layer(s).

Such a solution facilitates a display stack for an electronic device which is thinner than prior art, due to the lack of need for separate components such as microphone, loudspeaker, or discrete sensors. This, in turn, allows a very clean looking electronic device which is not weakened by openings which would be necessary for the function of such components. This furthermore allows the display panel to be arranged as close to the surface of the device as possible, due to not having to consider the placement of such other components, which facilitates a very high-quality image for the user.

In a possible implementation form of the first aspect, the support plate and the display panel are adjoined such that there is no gap between the support plate and the display panel, reducing the volume of the display stack.

In a further possible implementation form of the first aspect, the support structure further comprises a rim extending at least partially around an edge of the support plate, the rim protruding at an angle to the main surface of the support plate, the cover layer being fixed to the rim by means of a further adhesive layer. The rim protects the other, more delicate layers of the display arrangement, provides a surface for interconnecting the support structure and the cover layer, as well as increases the stability of the display stack. In a further possible implementation form ofthe first aspect, the main surface ofthe support plate has a substantially identical surface area as the main surface ofthe display panel, such that the support structure provides as much support as possible to the display panel.

In a further possible implementation form ofthe first aspect, the adhesive layer(s) comprise optically clear adhesive, allowing good visibility through the adhesive layers(s).

In a further possible implementation form of the first aspect, the cover layer comprises one of glass or polymer material.

In a further possible implementation form of the first aspect, the support structure comprises a heat conductive material, removing the need for intermediate heat conductive layers such as copper layers in the display panel and allowing the support structure to function as a grounding layer.

In a further possible implementation form of the first aspect, the display panel comprises a plurality of adjoining sub-layers, the sub-layers comprising at least one of a display layer, a sensor layer, a polarizer layer, and a touch sensor layer.

According to a second aspect, there is provided an electronic device comprising a chassis, an actuator, and a display stack according the above, the actuator being arranged between the display stack and the chassis, and being adapted to move the display stack relative to the chassis. This facilitates an electronic device which may be thinner than prior art due to a reduction in necessary components, and which is not weakened by openings which would be necessary for the function of such components.

In a possible implementation form of the second aspect, the electronic device further comprises a housing, the chassis being enclosed by the display stack and the housing, the display stack being fixed to the housing by means of a ductile adhesive.

This and other aspects will be apparent from and the embodiments described below. BRIEF DESCRIPTION OF THE DRAWINGS

In the following detailed portion of the present disclosure, the aspects, embodiments and implementations will be explained in more detail with reference to the example embodiments shown in the drawings, in which:

Fig. 1 shows a cross-sectional side view of an electronic device in accordance with an embodiment of the present invention; Fig. 2 shows a partial cross-sectional side view of an electronic device in accordance with an embodiment of the present invention;

Fig. 3 shows an exploded view of an electronic device in accordance with an embodiment of the present invention;

Fig. 4 shows a partial cross-sectional side view of a display stack in accordance with an embodiment of the present invention;

Fig. 5 shows a partial cross-sectional side view of a display stack in accordance with a further embodiment of the present invention;

Fig. 6 shows a partial cross-sectional side view of a display stack in accordance with yet another embodiment of the present invention; Fig. 7 shows a perspective view of a selection of components of an electronic device in accordance with an embodiment of the present invention. DETAILED DESCRIPTION

Figs. 1 to 3 and 7 show illustrations of an electronic device 2 comprising a chassis 8, at least one actuator 9, and a display stack 1 which described in more detail further below. The actuator(s) 9 is/are arranged between the display stack 1 and the chassis 8, and are adapted to move the display stack 1 relative to the chassis 8. The electronic device 2 further comprises a housing 10 which, together with the display stack 1, encloses the chassis 8. The display stack 1 may be fixed to the housing 10 by means of a ductile adhesive 11, as shown in Fig. 2.

The actuator(s) 9 vibrate the display stack 1 such that audio and haptic waves are generated. This allows a solution which does comprise separate components such as microphone, loudspeaker, or discrete sensors for generating vibration. This, in turn, allows a very clean looking electronic device which is not weakened by openings which would be necessary for the function of such components.

The display stack 1 , shown in detail in Figs 3 to 6, comprises a display arrangement and a support plate 6 supporting the display arrangement. The display arrangement comprises a plurality of adjoining layers, the layers being at least a cover layer 3, at least one adhesive layer 4, and a display panel 5.

In one embodiment, the cover layer 3 comprises one of glass or polymer material.

The display panel 5 may comprise a plurality of adjoining sub-layers, the sub-layers comprising at least one of a display layer, a sensor layer, a polarizer layer, and a touch sensor layer. The display layer may, e.g., be an OLED or AMOLED display layer.

The support structure 6 comprises a support plate 6a. A main surface of the support plate 6a is fixed to a main surface of the display panel 5 by means of at least one adhesive layer 4. The support plate 6a and the display panel 5 may be adjoined such that there is no gap between the support plate 6a and the display panel 5, i.e. the main surface of the support plate 6a is separated from the main surface of the display panel 5 by the adhesive layer 4 only.

The main surface of the support plate 6a may have a substantially identical surface area as the main surface of the display panel 5, however the two main surfaces may also be of different sizes. One or both of the main surfaces may also be divided into several sub surfaces, one or several sub-surfaces being adhered to one or several of the opposite sub surfaces.

The support structure 6 may also comprise a rim 6b, as shown in Figs 4 and 6. The rim 6b extends at least partially around an edge of the support plate 6a, possibly around the entire edge of the support plate 6a. The rim 6b protruding at an angle to the main surface of the support plate 6a, e.g. at 90° such that the support structure has a U-shaped cross-section. The rim 6b may be a separate component attached to the support plate 6a or to the cover layer 3, or the rim 6b may be integral with the support late 6a. A rim is preferable should one or several of the layers of the display panel 5 be very soft, e.g. due to a thick adhesive layer 4, in which case the rim helps stabilize the display stack 1 in order to make it durable and possible to generate vibrations.

The support structure 6 may comprise a heat conductive material, allowing heat generated by e.g. a processor to be conducted away from heat sensitive parts such as an OLED display layer. This allows a display stack 1 which comprises neither air gaps between display panel and support structure, which would otherwise be necessary in order to insulate the display layer from the processor, nor cushioning layers, which would be necessary in order to protect the more delicate layers of the display panel from impact with the support structure. Additionally, a heat conductive support structure 6 removes the need for intermediate heat conductive layers such as copper layers in the display panel. The support structure 6 may also function as a grounding layer. The heat conductive material may be, e.g., aluminum, magnesium, steel, or a composite comprising metal parts. The cover layer 3 may be fixed to the rim 6b by means of a further adhesive layer 7, such that the remainder of the display arrangement is substantially enclosed by the cover layer 3 and the support structure 6.

In the case the support structure 6 comprises only the support plate 6a, the cover layer 3 is adhered to one of the layers of the display arrangement, e.g. the display panel 5.

One or more of the adhesive layers 4, 7 may comprise optically clear adhesive.

The various aspects and implementations have been described in conjunction with various embodiments herein. However, other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed subject-matter, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination ofthese measured cannot be used to advantage.

The reference signs used in the claims shall not be construed as limiting the scope.

Claims

1. A display stack (1) for an electronic device (2) comprising

-a display arrangement comprising a plurality of adjoining layers, said layers comprising at least a cover layer (3), at least one adhesive layer (4), and a display panel (5),

-a support structure (6) comprising a support plate (6a), a main surface of said support plate (6a) being fixed to a main surface of said display panel (5) by means of said adhesive layer(s) (4).

2. The display stack (1) according to claim 1, wherein said support plate (6a) and said display panel (5) are adjoined such that there is no gap between said support plate (6a) and said display panel (5).

3. The display stack (1) according to claim 1 or 2, wherein said support structure (6) further comprises a rim (6b) extending at least partially around an edge of said support plate (6a), said rim (6b) protruding at an angle to said main surface of said support plate (6a), said cover layer (3) being fixed to said rim (6b) by means of a further adhesive layer (7).

4. The display stack (1) according to any one of the previous claims, wherein said main surface of said support plate (6a) has a substantially identical surface area as said main surface of said display panel (5).

5. The display stack (1) according to any one of the previous claims, wherein said adhesive layer(s) (4, 7) comprise optically clear adhesive.

6. The display stack (1) according to any one of the previous claims, wherein said cover layer (3) comprises one of glass or polymer material.

7. The display stack (1) according to any one of the previous claims, wherein said support structure (6) comprises a heat conductive material.

8. The display stack (1) according to any one of the previous claims, wherein said display panel (5) comprises a plurality of adjoining sub-layers, said sub-layers comprising at least one of a display layer, a sensor layer, a polarizer layer, and a touch sensor layer.

9. An electronic device (2) comprising a chassis (8), an actuator (9), and a display stack (1) according to any one of claims 1 to 8, said actuator (9) being arranged between said display stack (1) and said chassis (8), and being adapted to move said display stack (1) relative to said chassis (8).

10. The electronic device (2) according to claim 9, wherein said electronic device (2) further comprises a housing (10), said chassis (8) being enclosed by said display stack (1) and said housing (10), said display stack (1) being fixed to said housing (10) by means of a ductile adhesive (11).