WO2003049493A1

WO2003049493A1 - Display window for radiation of sounds in communication and multimedia devices

Info

Publication number: WO2003049493A1
Application number: PCT/DE2002/004137
Authority: WO
Inventors: Roland Aubauer
Original assignee: Siemens Aktiengesellschaft
Priority date: 2001-11-27
Filing date: 2002-11-08
Publication date: 2003-06-12
Also published as: DE10157790A1

Abstract

The invention relates to a mobile terminal device (1) comprising an opening in the area of the terminal device's display field that is covered at least in part by a display window (2) which radiates sound waves by means of actuators and is elastically mounted to the housing (1). The aim of the invention is to improve the mounting of the display window (2) by substantially, rigidly fixing at least one segment (3) of the display window's (2) edge to the housing. The display window is configured in an elastic manner inwards from the at least one substantially, rigidly fixed segment (3) so as to allow the display window (2) to radiate sound waves.

Description

description

Display window for sound radiation in communication and multimedia terminals

The invention relates to a mobile terminal according to the preamble of claim 1 and to a display window therefor.

Such a terminal is known for example from WO 00/024174 AI. The display window is used as a loudspeaker for sound radiation, which has considerable advantages for future mobile devices such as mobile phones, webpads, PDAs, notebooks, etc. Smaller end devices with improved sound reproduction with regard to bandwidth, volume and distortion, etc., in particular in the bass range, can be implemented. In addition, the risk of hearing damage can be avoided if the end device is accidentally held to the ear in hands-free mode. In hand-held device operation, in which a mobile phone is used on the ear, the surface radiation of the display window means that the positioning of the terminal device on the ear is uncritical compared to currently available devices with a smaller sound outlet opening.

In the display window, which is used as a loudspeaker, an excitation of bending vibrations is brought about by an actuator, so that sound radiation occurs. For this purpose, the display window must be elastically supported and mechanically and acoustically decoupled from the housing of the terminal.

So far, the mechanical and acoustic decoupling of the display window from the housing has been realized by a "floating" mounting of the display window via a foam ring. This foam ring with a rectangular cross-section has a corresponding height and width of about 1mm. The foam ring connects the edge of the display window to the housing of the terminal and is usually coated with adhesive on both sides, so that one side can be glued to the housing and the other side to the display window.

In this prior art, it is considered disadvantageous that the assembly of the display window to ensure the elastic mounting is complex.

Proceeding from this, the object of the invention is to improve the storage of the display windows in mobile end devices which use the display windows for sound radiation.

This object is achieved by a mobile terminal with a housing which has an opening in the area of a display panel of the terminal, which is at least partially covered with a display window which is actuated by actuators for emitting sound waves and is mounted on the housing, at least one section being provided of the edge of the display window is attached to the housing in a substantially rigid manner and the display window is designed to be elastic at an intermediate section inward from the at least one essentially rigidly attached section such that the display window is adapted to emit sound waves.

The basic idea of the invention is to use the display window itself for elastic storage, in which the inherent elasticity of the display window material is used for the elastic storage. In contrast to the prior art, for at least a portion of the edge of the display window there is no need to provide separate means, such as foam material, for the elastic mounting of the display window. However, the entire edge of the display window is preferably attached to the housing in an essentially rigid manner. In this embodiment, the foam ring customary in the prior art is completely saved, which simplifies the production and manufacture of the terminal. A further advantage is that the display window can be sealed better with respect to the housing, so that dirt or water can effectively be prevented from penetrating into the housing of the terminal. The rigid attachment of the edge of the display window namely allows the use of fasteners that have a significantly increased tightness to liquids than the foam rings previously used.

In order to provide the required elasticity of the display window for use as a loudspeaker, the display window is divided into an inner part, which is to function as a loudspeaker, and an outer part, which is rigidly attached to the housing. These two parts are elastically connected to each other by the intermediate section made of the display window material, which is modified so that it has such an elasticity that the inner part can work as a loudspeaker.

Several embodiments are conceivable for providing this elasticity. In one case, the material thickness of the display window can be substantially constant, but the material thickness of the display window is reduced at the intermediate section in such a way that the display window is adapted to emit sound waves. A reduced material thickness is thus present in the intermediate section, so that the required elasticity is available for mounting the inner part of the display window.

In another embodiment, the material thickness of the display window in its edge area from the inside of the Remove the display window from in the direction of the at least one essentially rigidly fastened section or towards the edge of the display window, including the intermediate section, in such a way that the display window is adapted to emit sound waves. In this case, the material thickness of the display window either decreases continuously or in the form of a shoulder from the inside to the outside, the material thickness in the outer area being selected in such a way that the required elasticity results.

In alternative embodiments to provide the required elasticity, material weakening is conceivable.

As a particular advantage of the embodiment in which the entire edge of the display window is fastened to the housing in a substantially rigid manner, it should be emphasized that a closed arc is arranged arbitrarily in the plane of the display window in which the material of the display window is weakened to provide elasticity can be. In particular, it is possible to choose the arrangement of the arc so that as many natural vibration modes as possible of the display window can be formed. In this respect, there is more freedom for the acoustic design of the display window, in particular with regard to the control of the acoustic modes of the display window. If as many natural vibration modes of the display window as possible can be formed, the frequency response for the display window is all the smoother. Since, in the prior art, acoustically non-optimal shapes are chosen for the outer shape of the display window, for example due to design requirements, the shape defined for design reasons also defines the acoustic quality of the display speaker used as a loudspeaker. In contrast, according to the invention, both design requirements and acoustic requirements for the display window can be taken into account independently of one another. For - essentially rigid - fastening of the display window to the housing of the terminal, the at least a portion of the edge of the display window or the edge as a whole can be glued to the housing of the terminal.

The housing preferably has a shoulder in the edge region of the display window which is designed and arranged to limit the deflection of the display window. This results in a higher protection of the display field under the display window against a deflection of the display window in the middle area towards the inside at high pressure from the outside.

With the mobile phone, a design insert in the

Display window can be integrated, wherein it is preferably arranged near the outside of the display window. In this way, a profile can be provided on the inside of the display window, with which the required elasticity is provided.

Part of the display window is preferably equipped inward of the intermediate section with a vibration-damping element for suppressing reverberation. This has the advantage of improved acoustic quality of the sound signal emitted by the display window.

Embodiments of the invention are described in more detail below with reference to the drawings. Show it:

FIG. 1 shows a partial cross-sectional view of an upper housing shell of a mobile telephone with a display window attached thereto in accordance with its first embodiment of the invention;

Figure 2 is a partial cross-sectional view of a housing upper shell of a mobile phone with attached Display window according to a second embodiment of the invention;

Figure 3 is a cross-sectional view of part of a display window with an integrated design insert and

Figure 4 is a plan view of a display window.

In FIG. 1, the transition area between a housing upper shell 1 and a to a

Sound radiation used display window 2 shown. An edge section 3 of the display window 2 rests on a shoulder 4 of the upper housing shell 1, with the interposition of an adhesive layer 5. The edge section 3 is thus essentially rigid, ie. apart from a remaining elasticity of the adhesive layer 5, attached to the housing shell 1. The edge section 3 of the display window 2 has a reduced material thickness compared to the remaining part of the display window 2. An intermediate section 21 with a reduced material thickness inwards from the edge section 3 is not glued to the housing upper shell 1, so that it shows its own elasticity. This own elasticity is dimensioned such that the part of the display window 2 located inwards from the edge section 3 can work as a loudspeaker. For this purpose, the inward part of the display window 2 is provided with actuators (not shown) which can excite the display window 2 to cause bending vibrations.

To limit a bending deflection of the display window 2 inwards, in the direction of a display field (not shown) of the mobile telephone, a shoulder 6 is provided on the upper housing shell 1, which in the present exemplary embodiment adjoins the shoulder 4 inwards. The height difference between paragraphs 4 and 6 is such that when the display window 2 bends in the direction of the display field below it Display field cannot be touched. In particular, when a bending vibration is carried out, the display window 2 hits the resulting edge 7 of the paragraph 6 rather than touching the display panel. It should be emphasized that instead of paragraph 6, any other mechanical configuration of the upper housing shell can be used to limit the deflection of the display window 2, which creates a stop point or a stop surface for the display window 2.

In order to prevent the part of the display window 2 used for sound radiation from re-oscillating, a vibration-damping element 22 is provided inwards from the intermediate section 21, which element is arranged between the shoulder 6 and an assigned section of the display window 2. Foam can be used as the material for the vibration-damping element 22.

FIG. 2 shows an alternative embodiment of a mobile terminal, with, as in FIG. 1, the

Transitional area between a housing upper shell 8 and a display window 9 is shown. An edge region 10 of the display window 9 is fixed essentially rigidly by means of an adhesive layer 11 to a shoulder 12 of the upper housing shell 8. The material thickness of the display window 9 is essentially constant. However, an intermediate section 13 of the display window 9 is provided inward of the edge section 10 and has a reduced material thickness. This intermediate section 13 has such inherent elasticity that the inward part of the

Display window 9 can be operated as a speaker.

Similar to the embodiment according to FIG. 1, a shoulder 15 of the upper housing shell 8 is provided to form an attachment point 14. The attachment point 14 avoids excessive deflection of the Display window 9 in the direction of a display field (not shown) of the mobile phone.

A vibration-damping element 23 is provided in the area of the intermediate section 13 in order to avoid a re-oscillation of a part of the display window 9 used for sound radiation. The vibration-damping element 23 is arranged within a depression which results from the reduced material thickness of the display window 9 in the intermediate section 13. Alternatively, a vibration-damping element in the embodiment according to FIG. 2 can also be arranged between the shoulder 15 and an assigned section of the display window 9.

Both in FIG. 1 and in FIG. 2, the upper housing shell 1 or the upper housing shell 8 extends over a distance along the display window 2 or the display window 9, so that, on the one hand, there is sufficient space for accommodating a respective display field and, on the other hand, the respective attachment point 7 or 14 is sufficiently inward according to its purpose.

In FIG. 3, the design of a display window 16 corresponds to that of the display window 9 from FIG. 2. One

Design insert 17 is integrated in the display window 16 and arranged in that area of the display window 16 in which there is a reduction in material thickness. As a result, the reduction in material thickness from the outside of the mobile phone is covered by the design insert 17. The design insert 17 can also be arranged to conceal actuators provided for operating the display window 16 as a loudspeaker.

FIG. 4 shows a plan view of a display window 18, the course of an arc having a reduced material thickness being shown in dashed lines. In Figure 4 are each Right-angled courses of the edge of the display window 18 and the arch 19 differ with regard to their side dimensions, so that the side dimensions of the display window 18 can be adapted to design requirements, while the course of the arch 19 with reduced material thickness with regard to acoustic requirements for one surrounded by the arch 19 Part 20 of the display window 18 can be optimized. It can be seen from this that, in contrast to the prior art, there is independence with regard to the geometric dimensions of the display window and a part of the display window 18 used as a loudspeaker.

Plexiglass (PMMA), Vivak, polycarbonate are considered as material examples for the display windows. to

Production of the display window, a spray process or a casting process can be used to implement the profiles described above in the form of sections with reduced material thickness. Mechanical processing of a display window, which has a constant material thickness in the initial state, is also possible. The first two methods, in particular, as illustrated in FIG. 4, make it possible to integrate design inserts into display windows.

Claims

claims

1. Mobile terminal with a housing that has an opening in the area of a display field of the terminal that is at least partially covered with a display window that is actuated by actuators for emitting sound waves and is mounted on the housing, characterized in that at least one section (3; 10) of the edge of the display window (2; 9; 16; 18) is fixed to the housing (1; 8) in a substantially rigid manner and the display window (2; 9; 16; 18) at an intermediate section (13; 21 ) inwardly of the at least one essentially rigidly fastened section (3; 10) is designed such that the display window (2; 9; 16; 18) is adapted to emit sound waves.

2. Terminal according to claim 1, characterized in that the entire edge of the display window (2; 9; 16; 18) is fixed substantially rigidly to the housing (2; 8).

3. Terminal according to claim 1 or 2, characterized in that the material thickness of the display window (2; 9; 16; 18) is constant, but on the elastic

Intermediate section (13) essentially reduces the material density of the display window (2; 9; 16; 18) so that the display window (2; 9; 16; 18) is adapted to emit sound waves.

4. Terminal according to claim 1 or 2, characterized in that the material thickness of the display window (2; 9; 16; 18) in its edge region from the inside of the display window (2; 9; 16; 18) in the direction of the at least one essentially rigidly fastened section of the display window (2; 9; 16; 18) including the elastic intermediate section (21) so that the display window (2; 9; 16; 18) is adapted to emit sound waves.

5. Terminal according to one of claims 1 to 4, characterized in that the at least one section (3; 10) of the edge of the display window is glued to the housing of the terminal.

6. Terminal according to one of claims 1 to 5, characterized in that the housing (1) in the edge region of the display window (2;

9; 16; 18) has a shoulder (6; 15) which is designed and arranged to limit the deflection of the display window (2; 9; 16; 18).

7. Terminal according to one of claims 1 to 6, characterized in that a design insert (17) in the display window (2; 9; 16; 18) is integrated.

8. Terminal according to claim 7, characterized in that the design insert (17) is arranged near the outside of the display window (2; 9; 16; 18).

9. Terminal according to one of claims 1 to 8, characterized in that a part of the display window (2; 9; 16; 18) inwards from the intermediate section (13; 21) with a vibration-damping element (22; 23) for suppressing ringing Is provided.

10. Display window for sound radiation in mobile devices, characterized in that the display window (2; 9; 16; 18) in an inner part for emitting sound waves and an outer part for attachment to a housing of the terminal, the inner part (20) and the outer part being connected via an intermediate section (13; 21) of the display window (2; 9; 16; 18) are connected to one another, which has such elasticity that the inner part (20) is adapted for excitation with bending waves for sound radiation.

11. Display window according to claim 10, characterized in that the intermediate section (13; 21) has a reduced material thickness compared to the rest of the display window (2; 9; 16; 18).