Abstract:
The invention relates to a display arrangement for establishing a flexible mounting of a liquid crystal display (LCD) module in an electronic equipment for minimize the impact on the LCD module of externally applied forces on the electronic equipment, e.g. dropping the electronic equipment. This is managed by having a gap between the LCD and the surrounding mechanics in the electronic equipment. The LCD module is positioned in relation to the surrounding mechanics by provisions of elastic and adhesive members between the LCD module and the surrounding mechanics in the electronic equipment.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to a display arrangement for holding a liquid crystal display (LCD) in a communication terminal that minimize the impact of external forces applied on the display arrangement.  
           [0003]    2. Description of Prior Art  
           [0004]    Display holder arrangements are widely known in different electronic equipment. The display arrangement in electronic equipment aims to firstly hold the display for it to perform its purpose, but also secondly protect the display from the impact from any external forces applied on the electronic equipment. The second purpose of protecting the display is of particular importance for portable devices that easily can be dropped and that are handled less carefully.  
           [0005]    Communication terminals, like mobile phones, have the disadvantage that they can not be rigid enough to easily resist external forces, as they would be too clumsy for the normal user. Only specially designed craftsman phones, like Nokia 6250™, have this very rigid design. In other phones or electronic equipment are the display arrangement designed to prevent impact on the displays by a flexible or adjustable mounting. More precisely were the earlier implementations of display arrangements in communication terminals constructed so that the LCD module was supported by the sidewalls or placed towards the sidewalls, and held in its position by the surrounding mechanics, that were applied directly on the LCD module. This caused a lot of problems with cracking displays after the communication terminal accidentally had been dropped.  
           [0006]    An example of earlier solutions has been described in the prior art document GB 2190529 A. In document of GB 2190529 A is described a liquid crystal display (LCD) mounted on a printed circuit board. The LCD is mounted behind an opening the edges of which serve as a bezel for the LCD. A resilient gasket extends the around the periphery of the LCD and is sandwiched between the LCD and the bezel to prevent movement of the LCD relative to the housing. Another examples of display arrangement are EP 0939 532 A2, EP 0709714 B1 and FR 2674295 A1, that all describes solution where the display has been rigidly positioned in a housing and where the display not is provided with provisions for flexibility.  
           [0007]    The claimed invention aims to provide an improved display arrangement that solves the above-mentioned problems.  
         SUMMARY OF THE INVENTION  
         [0008]    It is an object of the present invention is to provide a display arrangement that is flexible and where a liquid crystal display (LCD) module can resist externally applied forces on the display arrangement.  
           [0009]    According to a first preferred embodiment of the claimed invention this objective is obtained by a display arrangement that has a gap between the LCD module and the surrounding mechanics and where flexible material is used to retain the relative position of the LCD module to the surrounding mechanics.  
           [0010]    Another object of the invention is to a method for arranging a LCD in relation to a housing to enable a flexible display that adjusts to externally applied forces on a display arrangement and thereby minimize the risk cracking of the LCD.  
           [0011]    According to an preferred embodiment of the claimed invention this objective is obtained by a method for establishing a flexible display arrangement, where a liquid crystal display (LCD) is attached to a housing by provisions of an adhesive member along the periphery of the bottom surface of the LCD, having a cavity between the side walls of the housing and the side periphery of the LCD, and further applying an elastic member between the top surface of the LCD and the housing.  
           [0012]    Yet another object of the invention is to provide a method for mounting a display module in a display arrangement to provide that the LCD retains a relative position to the rest of the display arrangement.  
           [0013]    According to the preferred embodiment of the claimed invention this objective is obtained by a method for arranging a LCD in relation to a housing in an electronic equipment comprising the steps of applying an adhesive member along the periphery of the bottom surface of the LCD and attaching the LCD to a first housing part, mounting a second housing part including a elastic member on the first member, as to enabling the elastic member to establishing a pressure on the LCD, and retaining a relative position between the LCD and the housing parts. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0014]    The invention will be explained more fully below, by way of example, in connection with preferred embodiments and with reference to the drawing, in which:  
         [0015]    [0015]FIG. 1 show in two different perspective views a known embodiment of a communication terminal.  
         [0016]    [0016]FIG. 2 schematically shows the essential parts of a telephone for communication with a cellular network.  
         [0017]    [0017]FIG. 3 shows a display arrangement and the topside of a liquid crystal display module in the display arrangement.  
         [0018]    [0018]FIG. 4 shows a cross section of the display arrangement according to the invention.  
         [0019]    [0019]FIG. 5 shows a part of a detailed cross section of the display arrangement according to the invention.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0020]    According to a first aspect the display arrangement according to the invention will be described with reference to a hand portable phone, preferably a cellular/mobile phone. An embodiment of this phone is shown in FIG. 1, where a cellular/mobile phone  1  is shown in perspective. As will be seen, the phone is provided with a front cover  2  having a window frame  3  encircling the protection window of the display assembly  3 . The cellular/mobile phone comprises a user interface having an on/off button  4 , a speaker  5  (only openings are shown), a keypad  7 , a battery  14 , a display/LCD  3  and a microphone  6  (only openings are shown).  
         [0021]    The keypad  7  has a first group of keys  8  as alphanumeric keys, by means of which the user can enter a telephone number, write a text message (SMS), write a name (associated with the phone number), etc. Each of the twelve alphanumeric keys  8  is provided with a figure “0-9” or a sign “#” or “*” respectively. In alpha mode each key is associated with a number of letters and special signs used in the text editing.  
         [0022]    The keypad  7  additionally comprises two menu selections or soft-keys  9 , two call handling keys  12 , and a navigation-key  10 . The function of the soft-key depends on the state of the phone and the navigation in the menu by using a navigation-key. The present function of the menu selection keys  9  is shown in separate fields in the display  3  just above the keys  9 . The two call handling keys  12  are used for establishing a call or a conference call, terminating a call or rejecting an incoming call. This key layout is characteristic of e.g. the Nokia 6210™ phone.  
         [0023]    The navigation-key  10  is an up/down key and is placed centrally on the front surface of the phone between the display  3  and the group of alphanumeric keys  8 . Hereby the user will be able to control this key with his thumb. This is the best site to place an input key requiring precise motor movements. Many experienced phone users are used to one-hand handling. They place the phone in the hand between the fingertips and the palm of the hand. Hereby the thumb is free for inputting information.  
         [0024]    [0024]FIG. 2 schematically shows the most important parts of a preferred embodiment of the phone/terminal, said parts being essential to the understanding of the invention. The microphone  6  records the user&#39;s speech, and the analogue signals formed thereby are A/D converted in an A/D converter (not shown) before the speech is encoded in an audio part  20 . The encoded speech signal is transferred to a processor  18  (physical layer processor), which e.g. supports GSM terminal software. The processor  18  also forms the interface to the peripheral terminals of the apparatus, including RAM and ROM memories  17   a  and  17   b , a SIM card  16 , the display  3  and the keypad  7  (from FIG. 1) as well as data, power supply, etc. The processor  18  controls the communication with the network via the transmitter/receiver circuit  19  and an antenna  21 . The audio part  20  speech-decodes the signal, which is transferred from the processor  18  to the speaker  5  via a D/A converter (not shown).  
         [0025]    The processor  18  is connected via a bus  24  to a RAM memory  17   a  and a Flash ROM memory  17   b , a SIM card  16 , the display  3  and the keypad  7  (as well as data, power supply, etc.). Furthermore a phonebook  23  is connected to the processor  18  via the bus  24 . The phonebook  23  may be stored on the SIM card  16 , and/or in the Flash ROM memory  17   a.    
         [0026]    [0026]FIG. 3 schematically show a display arrangement according to a first embodiment of the claimed invention. A display module  30  includes a liquid crystal display (LCD)  31  having a frame  32 , connector pads  33  and lines (not shown) connecting the LCD  31  to the connector pads  33 . The connection between the connector pads  33  and the printed circuit board has been left out from FIG. 3 to simplify it. All the way around the LCD module  30  is an air gap or cavity  34 , and outside the gap or cavity is located a light guide  35 , wherein the LCD module has been disposed.  
         [0027]    The exact design of the rest of the lightguide is not a part of the invention, but is substantially similar to lightguides used in e.g. Nokia 6210™, 3310™, 3330™ or 6510™. The hatched section  36  around the inner periphery  37  of the lightguide  35  symbolize the rest of the lightguide  35 . The reference A-A in FIG. 3 is shown as a cross section in FIG. 4. The cross section of the lightguide  35  is more clear as well as the of the LCD module  30 . The air gap or cavity  34  around the LCD module  30  is also shown together with an air gap or cavity  38  between the bottom surface of the LCD module  30  and the lightguide  35 . Further is included a metal frame  39  that has been placed on top of the lightguide  35  to hold the LCD module  30  is position. The metal frame has been provided with an elastic gasket  40  along the inner periphery of the metal frame  39  to establish a flexible pressure on the topside of the LCD module  30 . The flexible pressure enables the LCD module  30  to adjust to externally applied forces on the display arrangement that otherwise would risk to crack under the externally applied forces.  
         [0028]    The metal frame  39  can be hold in its position by clips (not shown), snapping provisions or be provided with cut outs wherein welded plastic from the lightguide can project and thereby holding the metal frame in position. The metal frame  39  can cover over parts than the display arrangement that surrounds the display arrangement.  
         [0029]    In FIG. 5 is shown an enlarged part of the display arrangement including the lightguide  35 , the LCD module  30 , the metal frame  39  and the elastic gasket  40 . It also shows an adhesive member  42  that has been applied along the periphery of the bottom surface of the LCD module  30 . Outside and inside the adhesive  42  is an air gap  34  respectively  38  between the LCD module  30  and the lightguide  35 . The adhesive  42  has elastic properties to enables absorption on externally applied forces, similar properties to those of the elastic gasket  40 . The absorption of externally applied forces minimizes the impact on the LCD module  30 , and the risk that the LCD  31  cracks.  
         [0030]    The end  43  of the elastic gasket  40  appears to enter into the LCD module  30 , but this is made only to show that the elastic gasket end  43  comprises to some degree in order to apply a holding pressure on the LCD module  30 .  
         [0031]    The elastic gasket  40  is further provided with a flange  41  that serves as dust protection for the LCD module  30  and a protection window (not shown) on a front cover  2 . It does not need to be a lightguide that surrounds the LCD module, but can be any kind of surrounding mechanics or fixture, as long as there is an air gap or cavity around the LCD module. The lightguide can be replaced by an illuminating foil or other provisions that can supply the LCD module with lihgt for illumination.  
         [0032]    The invention is not limited to the above-described examples or to the drawings showing examples of an embodiment, but can be varied within the scope of the appended claims.