Display module

Abstract

The present invention relates to a display module and a vehicle comprising such a display module. The display module 1 comprises a backplate 2, a display frame 3 with a first surface 9 and a second su

Description

Description The present invention relates to a display module and a vehicle comprising such a display module. Display modules are well known from the state of the art. The known display modules comprise a backplate, a display frame and a display panel. The display module is built in a sandwich design such that the display frame is attached to the backplate, and the display panel is attached to the display frame. Thus, the display frame is ordered between the backplate and the display panel. An example of a display module 1 known from the state of the art is shown in Fig. 1. The display module 1 comprises a backplate 2, a display frame 3 and a display panel 4. Usually, the backplate comprises a thickness of 1mm to 2mm, depending on the area of the backplate, and usually is made of an AIMgZn alloy and is produced in a thixomolding process. The display frame 3 is usually made of Polycarbonate in an injection molding process and has an overall thickness of about 1mm. The display module 1 is set up in a sandwich design such that the display frame 3 is attached to the backplate 2 and the display panel 4 is attached to the display frame 3. The display panel 4 is attached to the display frame 3 via a double-sided adhesive tape 5 and the display frame 3 is attached to the backplate 2 via clipping means 6. At the ground of the backplate 2, between the display frame 3 and the backplate 2, optical components 7 such as a light conductor and foil stack can be seen. The usage of clipping means has some drawbacks, as it is very difficult to achieve a good flatness for the display frame assembled on the backplate, by clipping means. The display panel is a very sensitive component. Even the smallest flatness deviation means stress in the display panel, affecting its performance, leading to a lack of uniformity in the display panel, thus leading to Black MURA issues. The Black Mura Standard is a standard measurement method for evaluating uniformity in automotive displays. The Black MURA issues may lead to a high scrap rate due to unfulfillment of uniformity requirements of the displays which in turn leads to a high waste of materials. Even though the Backplate, due to being a stable component of the display module, may have a good, controlled flatness, the display frame, as already mentioned, is a very sensitive component as it is a flexible component of the display module. Bringing these two components, the backplate and the display frame, of the display module together by clipping means, therefore, may cause some issues. As known, the components, e.g., the clipping means, the backplate and the display frame, usually have tolerances, for example because of production process. These tolerances make a synchronization of all the clipping means nearly impossible, especially under considering that, for example, the clipping means are manufactured in different cavities or even come from different suppliers. Due to slight deviations of the individual components from each other, which can be caused by corresponding tolerances, it is not uncommon that after attachment of the display frame to the backplate by clipping means, the display frame has a wavy surface. The problem of a wavy surface for the display frame is becoming bigger with an increasing number of used clipping means. Therefore, a verification step is a common procedure during production in order to be sure that all the clipping means were clipped properly in respective clipping holes of the backplate and / or the display frame, and in order to verify that the display frame does not show a wavy surface. It is not unusual that an adjustment of the clipping means, e.g., in the clipping holes, must be done individually for each single clipping mean. This however means additional costs and high efforts. Also, the clipping holes in the display frame and / or the backplate have some drawbacks, in case that the display module is used in a wet bonding technology. In such a case, the clipping holes must be covered in order to prevent a bonding fluid from entering inside of the module, which would lead to an increased risk of a particle contamination. Furthermore, there is a risk of noise and friction between the Display Frame and the Backplate due to the usage of clipping means. From the state of the art, e.g., EP 3196 864 A1, it is known to attach the backplate to the optical components, i.e., the monitor, and the backplate to the display panel, using a double-sided adhesive tape. However, the EP 3 196 864 A1 does not describe a display module which comprises a display frame. Hence, the EP 3 196 864 A1 is not confronted with a problem of attaching a display frame to a backplate. Furthermore, EP 3 196 864 A1 is also not confronted with problems of the flatness of the display frame affecting the display panel with regard to its performance and with regard to Black MURA issues. It is an object of the present invention to provide a display module comprising a display frame and a backplate which overcomes at least one of the afore-mentioned problems. This object is achieved by a display module according to claim 1 and by a vehicle comprising such display module according to claim 6. The dependent claims include advantageous further developments and improvements of the present principles as described below. According to a first aspect, a display module comprises a double-sided adhesive cushion tape arranged between the first surface of the display frame and the backplate adhesively attaching the first surface of the display frame to the backplate. This bears the advantage that there is no need for additional clipping means to attach the display frame to the backplate. Therefore, there are no longer clipping holes needed to receive the clipping means. Furthermore, as a result, tolerances which where needed regarding the clipping means and other components such as backplates as well as the clipping holes must not be longer taken into consideration due to the lack of necessity of clipping means and clipping holes. This greatly simplifies production and verification of such display modules and avoids wavy surface. This in turn saves time and money. In addition, a high scrap rate due to unfulfillment of black homogeneity requirements and thus a high waste of materials is avoided with a display module according to the invention. The fact that clipping holes are no longer needed also eliminates the problem that the clipping holes must be covered during bonding process in order to prevent a bonding fluid from entering inside of the display module, which would lead to an increased risk of a particle contamination. By using the cushion tape, a good flatness of the Backplate is transferred, through the cushion tape to the flexible display frame making it to take the shape of the backplate. The cushion material of the cushion tape in between the two components, i.e., the backplate and the display frame, functions as a compensator for tolerances and reduces the stress which might be transferred via the display frame into the display panel. All in all, a better flatness on the surface of the display frame is achieved, resulting in a better uniformity which reduces Black MURA issues. It has been shown that a display module, which uses a double-sided adhesive cushion tape between the display frame and the backplate is more robust, e.g., at validation tests and also during the lifetime, when compared to a display module without such cushion tape. Furthermore, it has been shown that the usage of the cushion tape is providing a better fixation when compared to clipping means. Such display module can be used in any display module concept which has a similar structure with a backplate and a display frame. According to an embodiment of the present invention, the backplate comprises a tub-shaped form with a sidewall ending in an edge directed to the first surface of the display frame. The double-sided adhesive cushion tape is arranged at the edge of the backplate attaching the first surface of the display frame to the backplate. Due to this embodiment, a particularly good flatness is achieved. In addition, this embodiment is particularly easy to implement and saves a particularly high level of effort in a manufacturing process. Another advantage is that a space is created between the backplate and the frame, which can be optimally used for optic components. According to another embodiment of the present invention, the display frame comprises a first shank and a second shank. The first shank is arranged essentially orthogonal to the second shank. The first shank comprises the first surface and the second surface of the display frame. The first shank is arranged essentially parallel to the edge. The second shank protrudes beyond the edge of the tub-shaped backplate, so that the second shank is arranged essentially parallel to the sidewall of the backplate. Such an embodiment makes it easier to align the backplate and the display frame with each other, which greatly simplifies an assembly process and thus saves time and costs. According to another embodiment of the present invention, the double-sided adhesive cushion tape is frame-shaped and is arranged at the edge of the backplate attaching the first surface of the display frame to the backplate. Such an embodiments simplifies the attachment of display frame and backplate. According to another embodiment of the present invention, the double-sided adhesive cushion tape additionally protrudes beyond the edge over the sidewall of the backplate, additionally attaching at least a part of the second shank of the display frame to the sidewall of the tub-shaped backplate. Such an embodiment favors a particularly good and robust connection. According to a second aspect is directed to a vehicle that comprises a display module as described before. Further features of the present invention will become apparent from the following description and the appended claims in conjunction with the figures. Figures Fig. 1 shows a state-of-the-art display module for a motor vehicle, Fig. 2 shows an embodiment of a display module for a motor vehicle in accordance with the present invention, and Fig. 3 shows an alternative embodiment of a display module for a motor vehicle in accordance with the present invention. Detailed description For a better understanding of the principles of the present invention, embodiments of the invention will be explained in more detail below with reference to the figures. Like reference numerals are used in the figures for the same or equivalent elements and are not necessarily described again for each figure. It is to be understood that the invention is not limited to the illustrated embodiments and that the features described may also be combined or modified without departing from the scope of the invention as defined in the appended claims. Fig. 2 shows an embodiment of a display module 1 for a motor vehicle in accordance to the present invention. The display module 1 comprises a backplate 2, a display frame 3 with a first surface 9 and a second surface 10, and a display panel 4. The first surface 9 of the display frame 3 is attached to the backplate 2 and the second surface 10 of the display frame 3 is attached to the display panel 4. The backplate 2 comprises a tub-shaped form with a sidewall 11 ending in an edge 12 directed to the first surface 9 of the display frame 3. A frame-shaped double-sided adhesive cushion tape 8 is arranged at the edge 12 of the backplate 2 adhesively attaching the first surface 9 of the display frame 3 to the backplate 2. The double-sided adhesive cushion tape 8 thus is arranged between the first surface 9 of the display frame 3 and the backplate 2 attaching the first surface 9 of the display frame 3 to the backplate 2. The display frame 3 comprises a first shank 13 and a second shank 14. The first shank 13 is essentially arranged orthogonal to the second shank 14, i.e., in 90° ± 10°. The first shank 13 comprises the first surface 9 and the second surface 10 of the display frame 3. The first shank 13 is arranged essentially parallel to the edge 12. The second shank 14 protrudes beyond the edge 12 of the tub-shaped backplate 2 so that the second shank 14 is arranged essentially parallel to the sidewall 11 of the backplate 2. Fig. 3 shows an alternative embodiment of a display module for a motor vehicle in accordance with the present invention. The embodiment shown in fig. 3 differs from that shown in Fig. 2 only in that the double-sided adhesive cushion tape 8 additionally protrudes beyond the edge 12 over the sidewall 11 of the backplate2. Thus, a part of the second shank 14 of the display frame 3 is additionally attached to the sidewall 11 of the tub-shaped backplate 2. Reference Numerals 1 Display module 2 backplate 3 display frame 5 4 display panel 5 double-sided adhesive tape 6 clipping means 7 optical components 8 double-sided adhesive cushion tape 10 9 first surface 10 second surface 11 sidewall 12 edge 13 first shank 15 14 second shank

Claims

1. A display module (1) comprising:- a backplate (2),- a display frame (3) with a first surface (9) and a second surface (10), and- a display panel (4),- wherein the first surface (9) of the display frame (3) being attached to the backplate (2) and the second surface (10) of the display frame (3) being attached to the display panel (4),characterized in that, the display module (1) further comprising:- a double-sided adhesive cushion tape (8) arranged between the first surface (9) of the display frame (3) and the backplate (2) adhesively attaching the first surface (9) of the display frame (3) to the backplate (2).

2. Display module (1) according claim 1, characterized in that the backplate (2) comprises a tub-shaped form with a sidewall (11) ending in an edge (12) directed to the first surface (9) of the display frame (3) and wherein the double-sided adhesive cushion tape (8) is arranged at the edge (12) of the backplate (2) attaching the first surface (9) of the display frame (3) to the backplate (2).

3. Display module (1) according claim 2, characterized in that the display frame (3) comprises a first shank (13) and a second shank (14), wherein the first shank (13) is essentially arranged orthogonal to the second shank (14), wherein the first shank (13) comprises the first surface (9) and the second surface (10) of the display frame (3) and is arranged essentially parallel to the edge (12), and wherein the second shank (14) protrudes beyond the edge (12) of the tub-shaped backplate (2) so that the second shank (14) is arranged essentially parallel to the sidewall (11) of the backplate (2).

4. Display module (1) according one of claims 2 or 3, characterized in that the double-sided adhesive cushion tape (8) is frame-shaped being arranged atthe edge (12) of the backplate (2) attaching the first surface (9) of the display frame (3) to the backplate (2).

5. Display module (1) according claim 4, when dependent on claim 3,5 characterized in that the double-sided adhesive cushion tape (8) additionallyprotrudes beyond the edge (12) over the sidewall (11) of the backplate (2), additionally attaching at least a part of the second shank (14) of the display frame (3) to the sidewall (11) of the tub-shaped backplate (2).10 6. A vehicle comprising a display module (1) according to one of claims 1 to 5.

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