Abstract:
This invention provides a foldable and portable communication apparatus including a lower case, an upper case, and a connector. The connector is used to connect the lower case and the upper case in a foldable way. The lower case has a lower inner face. The upper case has an upper inner face and an upper outer face. The upper inner face is installed with a speaker to output an audio signal. The upper outer face is installed with an antenna. The antenna and the upper outer face form a predetermined tilt angle, and the predetermined tilt angle is less than 180 degree to reduce electromagnetic absorption by the user.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     This present invention relates to a portable communication apparatus, and more particularly, to a foldable and portable communication apparatus which can reduce the electromagnetic wave absorbed by users.  
         [0003]     2. Description of the Prior Art  
         [0004]     Mobile phones nowadays are very popular portable communication apparatuses. The American Federal Communications Commission (FCC) sets up standard criteria, the so called specific absorption rate (SAR), for the mobile phone or its apparatus. Other countries also set up similar standard criteria. SAR indicates the ratio of unit biomass to electromagnetic wave absorption. Under these standard criteria, in the prior art, the maximum SAR level of the ratio of head average unit mass to electromagnetic wave absorption cannot exceed a predetermined value while mobile phone cases radiate the maximum outputting power at normal usage position regarding to a mobile phone close to the head. SAR can be actually measured in a lab or computed by electromagnetic numerical analysis software.  
         [0005]     For foldable mobile phones, the method to reduce SAR of the prior art can be generally separated into two kinds: changing the circuit impedance or changing the radiating power of the antenna. However, changing the circuit impedance involves complicated circuit design, and changing the radiating power of the antenna may affect communication quality. Both ways of changing the foldable mobile phone of the prior art to reduce SAR involves complicated design modification.  
         [0006]     The efficiency of the radiating power of the antenna can be measured by effective isotropic radiated power (EIRP). In principle, when the communication distance is fixed, the bigger of the value of EIRP, the stronger the receiving signal, and the better the communication quality. In contrast, the same EIRP can exchange for farther communication distance or bigger covering range in the condition of the same communication quality and the same strength of receiving signal. When designing mobile phones, the EIRP must also be taken into consideration in addition to the fact that SAR should be reduced. In other words, the communication quality should be maintained while reducing the electromagnetic wave absorbed by users.  
         [0007]     A foldable mobile radio equipment was disclosed in Japan patent No. 2003-087375, which includes an upper case and a lower case. An antenna is disposed in the lower case and connected with the upper case by complicated machinery design. The major objective of the Japan patent is to avoid a situation in which radio wave reception sensitivity is reduced by antenna interference.  
         [0008]     It is very important to reduce SAR and also take EIRP into consideration while designing the portable communication apparatus.  
       SUMMARY OF THE INVENTION  
       [0009]     The major objective of the present invention is to provide a kind of foldable and portable communication apparatus to reduce the electromagnetic wave absorbed by users.  
         [0010]     The foldable and portable communication apparatus of the present invention includes a lower case, an upper case, and a connector. The connector is used for connecting the lower case and the upper case in a foldable manner. The lower case includes a lower inner face. The upper case includes an upper inner face and an upper outer face. The upper inner face is installed with a speaker to output a first audio signal. The upper outer face is installed with an antenna. The antenna and the upper outer face define a predetermined tilt angle, and the predetermined tilt angle is less than 180 degree.  
         [0011]     In the foldable and portable communication apparatus of the present invention, the antenna is installed in the upper case, and the predetermined tilt defined by the antenna and the upper outer case is less than 180 degree; this design keeps the radiation of the electromagnetic wave field, radiated by the antenna, away from a user who uses the communication apparatus, so as to reduce the electromagnetic energy absorbed by the user. Applying the present invention can reduce SAR of the foldable and portable communication apparatus and can also maintain EIRP at the same time, without complicated machinery or circuit design.  
         [0012]     The advantage and spirit of the invention may be understood by the following recitations together with the appended drawings. 
     
    
     BRIEF DESCRIPTION OF THE APPENDED DRAWINGS  
       [0013]      FIG. 1  is an external view diagram of the foldable and portable communication apparatus of the present invention.  
         [0014]      FIG. 2  is a lateral view of  FIG. 1  wherein the portable communication apparatus is in an unfolded state.  
         [0015]      FIG. 3  is a lateral view of another embodiment of the present invention wherein the foldable and portable communication apparatus is in a folded state.  
         [0016]      FIG. 4  is a lateral view of  FIG. 3  wherein the portable communication apparatus is in an unfolded state.  
         [0017]      FIG. 5  is a table of test results showing SAR, EIRP, and the tilt angle of the antenna of the portable communication apparatus.  
         [0018]      FIG. 6  is a schematic diagram of the electromagnetic wave energy distribution corresponding to the tilt angle of the antenna installed in the test of  FIG. 5  which is 180 degree.  
         [0019]      FIG. 7  is a schematic diagram of the electromagnetic wave energy distribution corresponding to the tilt angle of the antenna installed in the test of  FIG. 5  which is 110 degree. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0020]     Referring to  FIG. 1  and  FIG. 2 ,  FIG. 1  is an outer-view diagram of the foldable and portable communication apparatus  10  of the present invention, and  FIG. 2  is a lateral view of  FIG. 1  wherein the portable communication apparatus  10  is in an unfolded state. In an embodiment of the present invention, a foldable and portable communication apparatus  10  includes an upper case  12 , a lower case  20 , and a connector  24 . The connector  24  is used for connecting the upper case  12  and the lower case  20  in a foldable manner.  
         [0021]     The lower case  20  includes a lower inner face  19 . The lower inner face  19  is installed with a plurality of input buttons  18  to provide the user a medium for inputting an alphabet, a character, or a number. The upper case  12  includes an upper inner face  13  and an upper outer face  14 . The upper inner case face  13  is installed with a display panel  11  to display an alphabet, a character, a number, a graphic, or an image.  
         [0022]     The upper case  12  also includes a first side  15  and a second side  16 , wherein the first side  15  is closer to the connector  24 , and the second side  16  is further away from the connector  24 . The upper outer face  14  is installed with an antenna  22  in the vicinity of the first side  15 .  
         [0023]     When the portable communication apparatus  10  is in a non-communicating state, or standby mode, the upper case  12  and the lower case  20  are kept in the folded manner by the connector  24 , so that the upper inner face  13  and the lower inner face  19  contacts each other due to the folding. When the portable communication apparatus  10  is in a communication state, the upper case  12  and the lower case  20  are kept in the unfolded manner by the connector  24 .  
         [0024]     In the embodiment illustrated in  FIG. 1  and  FIG. 2 , the connector  24  includes a shaft member  25 , recess portions  21  formed in the lower case  20 , and two holes formed in the lower case  20 . The shaft member  25  includes an axle  26  and two contact portions which are disposed in the two holes of the lower case. The upper case  12  rotates through the axle  26  of the shaft member  25  which enables the upper case  12  and the lower case  20  to be kept in a folded or unfolded manner. In another embodiment, the connector  24  includes two shaft members  25 , wherein one contact portion of each shaft member  25  is disposed in the corresponding hole of the lower case  20 , and the axle  26  of the two shaft members  25  correspond with each other to allow the upper case  12  to rotate through the axle  26  of the two shaft members  25 .  
         [0025]     The upper inner face  14  is installed with a speaker  17  for outputting a first audio signal. The lower inner face  19  is installed with a microphone (not shown) for receiving a second audio signal. When the communication apparatus  10  is in a communicating state, the upper case  12  and the lower case  20  are kept in an unfolded manner by the connector  24 , so that the user hears the first audio signal by approaching the speaker  17  of the upper inner face  13 . Furthermore, when the communication apparatus  10  is in a communicating state, the user can also send out the second audio signal by approaching the microphone of the lower inner face  19 , and the second audio signal is received by the microphone.  
         [0026]     The antenna  22  is a dipole antenna in a column shape, and at least a section of the antenna protrudes from the upper outer face  14 . The antenna  22  and the upper outer face  14  define a predetermined tilt angle A which is less than 180 degree. Because the antenna  22  is installed on the upper case  14 , the antenna  22  moves with the upper case  12 , wherein this kind of moving mechanism does not require complicated machinery design while the upper case  12  and the lower case  20  are kept in an unfolded manner.  
         [0027]     In the portable communication apparatus  10 , the predetermined tilt angle A corresponds to an electromagnetic wave field that the antenna  22  radiates. The electromagnetic wave field changes accordingly when the predetermined tilt angle A is changed. Changing the predetermined tilt angle A of the antenna  22  keeps the radiation of the electromagnetic wave field radiated by the antenna  22  away from the user who uses the communication apparatus  10 , so as to reduce the electromagnetic energy absorbed by the user.  
         [0028]     Comparing with the foldable and portable communication apparatus of the prior art, the portable communication apparatus  10  of the present invention is very different. In the foldable and portable communication apparatus of the prior art, the antenna protrudes in a direction parallel with the lower case, and the antenna correspondingly parallels with the user&#39;s head while the user listens with their ears close to the portable communication apparatus of the prior art. In the portable communication apparatus  10  of present invention, as the antenna  22  is disposed on the first side  15  of the upper case  14  in a predetermined tilt angle A of less than 180 degree, the antenna  22  is correspondingly away from the user&#39;s head while the user unfolds the portable communication apparatus and listens with his/her ear close to the upper inner face  13 , as illustrated in  FIG. 2 . Therefore, the electromagnetic wave field radiated by the antenna  22  of the portable communication apparatus  10  of the present invention is kept away from the user who uses the portable communication apparatus  10 , so as to reduce the electromagnetic wave energy absorbed by the user. The invention does not require complicated machinery and circuit design to be put into practical application.  
         [0029]     In different embodiments, besides taking the predetermined tilt angle A, defined by the antenna  22  and the upper outer face  14 , into consideration, the connector  24  can be different structures. The design of the connector  24  mainly takes the following aspects into consideration: the upper case  12  should be able to rotate through the axle  26  of the shaft member  25  in order to keep the upper case  12  and the lower case  20  in a folded or unfolded manner, and the antenna  22  disposed on the upper case  12  should not collide with the lower case  20  while the portable communication apparatus  10  is in the unfolded manner, so that the user can hold and use the portable communication apparatus  10  by hand comfortably. In different embodiments, the antenna  22  is correspondingly away from the user&#39;s head while the user unfolds the portable communication apparatus, and the electromagnetic wave field radiated by the antenna  22  of the portable communication apparatus  10  of the present invention is kept away from the user who uses the portable communication apparatus  10 , so as to reduce the electromagnetic wave energy absorbed by the user.  
         [0030]     Besides, in different embodiments, the antenna  22  of the portable communication apparatus  10  can be installed in the vicinity of the second side  16  of the upper outer face  13 , and the predetermined tilt angle defined by the antenna  22  and the upper case is less than 180 degree. Please refer to  FIG. 3  and  FIG. 4 ;  FIG. 3  is a lateral view of another embodiment of the present invention wherein the foldable and portable communication apparatus  30  is in a folded state, and  FIG. 4  is a lateral view of  FIG. 3  wherein the portable communication apparatus  30  is in an unfolded state. According to another embodiment of the present invention, the portable communication apparatus  30  includes an upper case  32 , a lower case  40 , and a connector  44 . The main difference between the portable communication apparatus  10  and the portable communication apparatus  30  is the structure of the connector. In the portable communication apparatus  30 , the connector  44  includes a shaft member  45 . The lower case  40  includes two recess portions, and the structure of the side  35  of the upper case  32  corresponds to the two recess portions of the lower case  40 , so as to allow the upper case  32  to rotate through the axle  46  of the shaft member  45  and to keep the upper case  32  and the lower case  40  in the folded or unfolded manner.  
         [0031]     In the portable communication apparatus  30 , as illustrated in  FIG. 3  and  FIG. 4 , the antenna  42  is disposed on the first side  35  of the upper case  32 , and the predetermined tilt angle B defined by the antenna  42  and the upper outer face  34  is less than 180 degree. In different embodiments, the tilt angle B can be different angle less than 180 degree. The electromagnetic wave field radiated by the antenna  42  changes accordingly when the predetermined tilt angle B is changed. Besides the tilt angle B, the design of the corresponding structures of the connector  44  and the upper case  32  and the lower case  40  can have different manners that are well-known to machinery designers of general foldable communication apparatuses, so it will not be described in detail again.  
         [0032]     In the portable communication apparatus  30 , the upper inner face  33  is installed with a speaker, and the lower inner face  39  is installed with a microphone. The antenna  42  is correspondingly away from the user&#39;s head while the user unfolds the portable communication apparatus  30  to listen, and the electromagnetic wave field radiated by the antenna  42  is kept away from the user who uses the portable communication apparatus  30 , so as to reduce the electromagnetic wave energy absorbed by the user.  
         [0033]     Besides, in different embodiments, the antenna  42  of the portable communication apparatus  30  can also be installed in the vicinity of the second side  36  of the upper outer face  34 , and the predetermined tilt angle defined by the antenna  42  and the upper outer case  34  is less then 180 degree.  
         [0034]     Please refer to  FIG. 5 ,  FIG. 6 , and  FIG. 7 ;  FIG. 5  is a table of test results showing SAR, EIRP, and the tilt angle of the antenna of the portable communication apparatus;  FIG. 6  is a schematic diagram of the electromagnetic wave energy distribution corresponding to the tilt angle of the antenna installed in the test of  FIG. 5  which is 180 degree, and  FIG. 7  is a schematic diagram of the electromagnetic wave energy distribution corresponding to the tilt angle of the antenna installed in the test of  FIG. 5  which is 110 degree. In one of the test experiments, the changes of the maximum SAR value and the maximum ERIP value of the portable communication apparatus at different tilt angles will be tested in a condition with the same communication mode (CDMA), channel (384), and conducted power (25 dBM). In  FIG. 5 , the tilt angles C 1 , C 2 , C 3 , and C 4  defined by the tester, the antenna, and the portable communication apparatus respectively are 180, 150, 135, and 110 degree.  FIG. 6  and  FIG. 7  are respectively the equivalence energy curve corresponding to the electromagnetic wave in which the tilt angles are 180 degree and 110 degree, as defined by the antenna and the portable communication apparatus in  FIG. 5 . In  FIG. 7 , the antenna is inclined to the back side of the portable communication apparatus, so the diagram fails to display the tilt angle of the antenna.  
         [0035]     When the tilt angle decreases gradually from 180 degree, SAR also gradually decreases according to the test results of  FIG. 5 . In other words, the smaller the tilt angle of the antenna, the smaller the maximum SAR value measured. The coil circle  66  of  FIG. 6  and the coil circle  68  of  FIG. 7  respectively represent the covered region of higher SAR while the tilt angles are respectively 180 degree (C 1 ) and 110 degree (C 4 ). The region  681  of the high SAR, while the tilt angle is 110 degree, is smaller than the region  661  of the high SAR while the tilt angle is 180 degree. Comparing the respective area marked by the coil circle  62  of  FIG. 6  with that of the coil circle  64  of  FIG. 7 , the electric field energy in the vicinity of the antenna while the tilt angle is 110 degree ( FIG. 7 ) is weaker than while the tilt angle is 180 degree ( FIG. 6 ). However, comparing the ERIP while the tilt angles are respectively 180 and 110 degree shows little difference. Results of the above indicate that if the tilt angle of the antenna is closer to C 4 , SAR is smaller, but EIPR thereof will not reduce.  
         [0036]     In the foldable and portable communication apparatus of the present invention, the antenna is installed in the upper case, and the tilt angle defined by the antenna and the upper outer face is less than 180 degree. When the user unfolds the portable communication apparatus to listen, the antenna is correspondingly away from the user&#39;s head to keep the electromagnetic wave field radiated by the antenna away from the user who uses the communication apparatus, so as to reduce the electromagnetic energy absorbed by the user and to keep the efficiency of radiation of the antenna at the same time. The invention can be applied in practice for the foldable and portable communication apparatus without requiring complicated machinery or circuit modification.  
         [0037]     With the example and explanations above, the features and spirits of the invention will be hopefully well described. Those skilled in the art will readily observe that numerous modifications and alterations of the device may be made while retaining the teaching of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.