Abstract:
There is provided a communication device including (a) a device body, (b) an operator formed with the device body, (c) a displaceable section which is displaced by the operator, (d) a displacement detector which transmits a control signal in accordance with displacement of the displaceable section, and (e) a controller which operates the communication device in accordance with the control signal. For instance, when the communication device includes a display screen, and the controller changes what is displayed in the display screen, in accordance with the control signal. The communication device provides enhanced operability in comparison with a conventional communication device.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a communication device such as a cellular phone, and a method of operating a communication device. 
     2. Description of the Related Art 
     Data can be input into a communication device such as a cellular phone in several ways. A conventional cellular phone is generally designed to have keys in a front thereof Various functions of a cellular phone are assigned to the keys. A user can select a desired function of a cellular phone by pushing a key associated with the desired function. 
     Apart from the above-mentioned example, data can be input into a cellular phone as follows. 
     FIG. 1 illustrates a first example of a cellular phone. The illustrated cellular phone has number keys  81  on a front thereof Various functions are assigned to the number keys  81 . A user can select a desired function of the cellular phone by pushing two or more of the number keys  81  in combination. 
     FIG. 2 illustrates a second example of a cellular phone. The illustrated cellular phone has an operation key  91  on a front thereof By pushing the operation key  91  at an upwardly directed arrow, what is displayed in a display screen  92  is upwardly scrolled, and by pushing the operation key  91  at a downwardly directed arrow, what is displayed in the display screen  92  is downwardly scrolled. 
     FIG. 3 illustrates a third example of a cellular phone. The illustrated cellular phone has an operation dial  101  at a left side of the cellular phone. By rotating the operation dial  101 , what is displayed in a display screen  102  can be scrolled. 
     However, the above-mentioned conventional cellular phones are accompanied with the following problems. 
     In the first example illustrated in FIG. 1, it is assumed that combinations of the number keys  81  are known to a user, because various functions of the cellular phone are assigned to such combinations. Accordingly, a user has to memorize combinations of the number keys  81 , or refer to a function table indicative of correspondence between functions of the cellular phone and combinations of the number keys  81 , each time he/she makes a call. 
     In the first and second examples illustrated in FIGS. 1 and 2, respectively, the cellular phones are held by a user with fingers indicated with broken lines. Hence, when the number keys  81  or the operation key  91  is to be operated, a user has to take his/her thumb off the cellular phone, and operate the number key  81  or the operation key  91  with his/her thumb  93  in such a manner as illustrated in FIG.  2 . As an alternative, a user has to operate the number key  81  or the operation key  91  with the other hand (not illustrated). Thus, a user is laborious in either way. 
     In the third example illustrated in FIG. 3, the operation dial  101  is positioned so that the operation dial  101  can be operated with either a thumb  103  when a user holds the cellular phone with his/her left hand or a forefinger (not illustrated) when a user holds the cellular phone with his/her right hand. 
     However, the operation dial  101  is designed such that it can be readily operated with a thumb  103  of a user. Hence, when the operation dial  101  is arranged at a left side of the cellular phone as illustrated in FIG. 3, the operation dial  101  can be readily operated with a left hand of a user, which means that the operation dial  101  is operated with some difficulty when it is operated with a right hand of a user. 
     In addition, in the first to third examples illustrated in FIGS. 1 to  3 , a user is required to push the keys  81  or  91 , or rotate the operation dial  101  many times until he/she can retrieve or select a desired function. This is somewhat laborious to a user. 
     Japanese Unexamined Patent Publication No. 7-220552 has suggested a switch to be used for an electronic device, comprising a portion rotatable for switching connections, a second portion fixed on a supporter, and a switch knob mounted on the second portion by means of assembly means and fastener means. 
     Japanese Unexamined Patent Publication No. 10-65786 has suggested a portable radio-signal communication device including a rotary dial formed at a side of a device body. The rotary dial is designed to be rotatable about a rotation shaft, and is supported such that the rotary dial together with the rotation shaft can be pushed into the device. When the rotary dial is pushed into the device, the communication device is put into a mode for inputting data thereinto. A desired alphabet is selected by rotating the rotary dial. Since the rotary dial is arranged at a side of a device body, a user can operate the rotary dial with slight movement of a finger or fingers. The rotary dial slightly extends beyond a side of the device body so as not to interfere with a user&#39;s face while he/she is making a call. 
     Japanese Unexamined Patent Publication No. 10-28166 has suggested a method of inputting data into a cellular phone. In accordance with the method, data associated with telephone numbers can be displayed at a display screen at the first and second orders by operating an operator arranged at a side of a device body. Then, data displayed at the display screen is input into the cellular phone by further operating the operator. The operator includes a rotary member rotatable about a rotation axis. By rotating the rotary member in a first direction, data is displayed at the display screen at the first order, and by rotating the rotary member in a second direction which is opposite to the first direction, data is displayed at the display screen at the second order. By pushing the operator down, data displayed at the display screen is input into the cellular phone. 
     Japanese Unexamined Patent Publication No. 11-8686 has suggested a telephone including a knob arranged in parallel with a display screen, a detector which detects a direction in which the knob rotates, and a controller which displays data about telephone numbers stored therein, at the display screen in accordance with results of the detection of the detector. 
     The international publication WO95/31863 has suggested a terminal communication device including a rectangular parallelopiped body having a radio-displacement detector and a radio-signal receiver, and an operator. The body has a straight portion defining a side of the body, and a projecting portion outwardly projecting beyond the straight portion and formed integral with the straight portion. The operator is formed at the projecting portion, and includes a single operation member movable in positive and negative directions. The operator inputs data into the radio-displacement detector and receiver, and switches operation between the radio-displacement detector and receiver. The projecting portion has an arcuate surface extending beyond the side of the body. The single operation member is comprised of a rotary member rotatable relative to the body. 
     SUMMARY OF THE INVENTION 
     In view of the above-mentioned problem of the prior art, it is an object of the present invention to provide a communication device which can be operated well with either a right or left hand of a user to thereby enhance operability thereof. 
     In one aspect of the present invention, there is provided a communication device including (a) a device body, (b) an operator formed with the device body, (c) a displaceable section which is displaced by the operator, (d) a displacement detector which transmits a control signal in accordance with displacement of the displaceable section, and (e) a controller which operates the communication device in accordance with the control signal. 
     For instance, the controller may be designed to select one of functions of the communication device in accordance with the control signal. 
     It is preferable that the communication device further includes a display screen formed with the body, in which case, the controller may change what is displayed in the display screen, in accordance with the control signal. 
     It is preferable that the communication device includes two operators which are formed at opposite sides of the communication device. 
     It is preferable that the displacement detector keeps transmitting the control signal while the displaceable section is kept displaced. 
     It is preferable that the displacement of the displaceable section is comprised of at least one of a degree of expansion or contraction, a degree of deformation, a degree of angular displacement, and a degree of torsion. 
     It is preferable that the displacement detector transmits the control signal in accordance further with a direction in which the displaceable section is displaced. 
     It is preferable that the communication device further includes a converter which converts the displacement of the displaceable section into electric energy. 
     It is preferable that the displaceable section is composed of elastic material deformable by the operator. 
     It is preferable that the displacement detector transmits first to N-th control signals in accordance with the displacement of the displaceable section, wherein N is an integer equal to or greater than 2, the controller operating the communication device at first to N-th rates in response to the first to N-th control signals, respectively. 
     It is preferable that the operator is designed to be rotatable relative to the device body and to extend beyond opposite sides of the device body. 
     It is preferable that wherein the communication device includes two operators having arcuate surfaces symmetrical with each other about a center of the device body. 
     It is preferable that the operator includes a non-displaceable section which is not displaced by the operator, the communication device further including a deformation detector which is connected to both of the displaceable section and the non-displaceable section to thereby detect deformation of the displaceable section and transmit a detection signal in accordance with the thus detected deformation, the displacement detector transmitting the control signal in accordance with the detection signal. 
     It is preferable that the communication device includes two deformation detectors located horizontally symmetrical with each other about a center of the device body. 
     It is preferable that the communication device includes four deformation detectors located horizontally and vertically symmetrical with one another about a center of the device body. 
     It is preferable that the displacement detector includes a sensor having a wheatstone bridge structure. 
     It is preferable that the operator is formed integral with the device body. 
     There is further provided a communication device including (a) a device body, (b) at least one operator having an outer arcuate surface partially extending beyond the device body, and rotatable relative to the device body, (c) a displaceable section which is displaced by the operator, (d) a displacement detector which detects displacement of the displaceable section and transmits a detection signal accordingly, and (e) a controller which operates the communication device in accordance with the detection signal. 
     It is preferable that the communication device further includes a supporter fixed to the device body and having an arcuate outer surface having the same curvature as a curvature of an inner arcuate surface of the operator, the supporter supporting the operator thereon for rotation. 
     It is preferable that the device body is formed with a cut-out having an inner arcuate surface having the same curvature as a curvature of the outer arcuate surface of the operator, the outer arcuate surface of the operator being in facing relation to the inner arcuate surface of the cut-out. 
     It is preferable that the displacement detector includes (a) a non-deformable portion fixed to the device body, (b) an deformable portion connecting the non-deformable portion to the operator, and (c) a deformation detecting device located across the non-deformable portion and the deformable portion for detecting a degree of deformation of the deformable portion. 
     It is preferable that the displacement detector further includes an auxiliary deformable portion connecting the non-deformable portion to the operator, the deformable portion connecting to the non-deformable portion at one of upper and lower edges of the non-deformable portion, the auxiliary deformable portion connecting to the non-deformable portion at the other edge of the non-deformable portion. 
     It is preferable that the communication device further includes a second deformation detecting device located across the non-deformable portion and the auxiliary deformable portion for detecting a degree of deformation of the auxiliary deformable portion. 
     It is preferable that the communication device further includes a display screen formed with the body, and wherein the controller changes what is displayed in the display screen, in accordance with the detection signal. 
     It is preferable that the displacement detector keeps transmitting the detection signal while the displaceable section is kept displaced. 
     It is preferable that the displacement detector transmits the detection signal in accordance further with a direction in which the displaceable section is displaced. 
     It is preferable that the displacement detector transmits first to N-th detection signals in accordance with the displacement of the displaceable section, wherein N is an integer equal to or greater than 2, the controller operates the communication device, at first to N-th rates in response to the first to N-th detection signals, respectively. 
     It is preferable that the displacement detector transmits first to N-th detection signals in accordance with the displacement of the displaceable section, wherein N is an integer equal to or greater than 2, the controller changes what is displayed in the display screen at first to N-th rates in response to the first to N-th detection signals, respectively. 
     It is preferable that the displacement detector includes a sensor having a wheatstone bridge structure. 
     It is preferable that the displacement detector transmits the detection signal only when the displacement of the displaceable section is equal to or greater than a threshold displacement. 
     There is still further provided a communication device including (a) a device body, (b) a first operator having an outer arcuate surface partially extending beyond the device body, and rotatable relative to the device body, (c) a second operator having an outer arcuate surface partially extending beyond the device body, and rotatable relative to the device body, the first and second operators being formed at opposite sides of the communication device, (d) a first displaceable section which is displaced by the first operator, (e) a second displaceable section which is displaced by the second operator, (f) a first displacement detector which detects displacement of the first displaceable section and transmits a first detection signal accordingly, (g) a second displacement detector which detects displacement of the second displaceable section and transmits a second detection signal accordingly, and (h) a controller which operates the communication device in accordance with at least one of the first and second detection signal. 
     It is preferable that the first and second operators rotate in synchronization with each other. 
     It is preferable that the first operator rotates in a direction opposite to a direction in which the second operator rotates. 
     It is preferable that the first and second operators are rotatable independently of each other. 
     It is preferable that the communication device further includes first and second supporters fixed to the device body and each having an arcuate outer surface having the same curvature as a curvature of an inner arcuate surface of each of the first and second operators, the first and second supporters supporting the first and second operators thereon for rotation, respectively. 
     It is preferable that the device body is formed with first and second cut-outs each having an inner arcuate surface having the same curvature as a curvature of the outer arcuate surface of each of the first and second operators, the outer arcuate surface of each of the first and second operators being in facing relation to the inner arcuate surface of each of the first and second cut-outs, respectively. 
     It is preferable that the communication device further includes a non-deformable portion fixed to the device body, the first displaceable section being connected to both the first operator and the non-deformable portion, the second displaceable section being connected to both the second operator and the non-deformable portion, the first displacement detector being located across the non-deformable portion and the first displaceable section, the second displacement detector being located across the non-deformable portion and the second displaceable section. 
     It is preferable that the communication further includes a first auxiliary displaceable section being connected to both the first operator and the non-deformable portion, and a second auxiliary displaceable section being connected to both the second operator and the non-deformable portion. 
     It is preferable that the first displaceable section is connected to the non-deformable portion at one of upper and lower edges of the non-deformable portion, and the first auxiliary displaceable section is connected to the non-deformable portion at the other edge of the non-deformable portion, and wherein the second displaceable section is connected to the non-deformable portion at one of upper and lower edges of the non-deformable portion at the opposite side to the first displaceable section, and the second auxiliary displaceable section is connected to the non-deformable portion at the other edge of the non-deformable portion at the opposite side to the first auxiliary displaceable section. 
     It is preferable that the communication device further includes a third displacement detector which detects displacement of the first auxiliary displaceable section and transmits a third detection signal accordingly, and a fourth displacement detector which detects displacement of the second auxiliary displaceable section and transmits a fourth detection signal accordingly. 
     It is preferable that the communication device further includes a display screen formed with the body, and wherein the controller changes what is displayed in the display screen, in accordance with at least one of the first and second detection signals. 
     It is preferable that the first and second displacement detector keep transmitting the first and second detection signals while the first and second displaceable sections are kept displaced. 
     It is preferable that the first and second displacement detectors transmit the first and second detection signals in accordance further with directions in which the first and second displaceable sections are displaced. 
     It is preferable that the third and fourth displacement detectors transmit the third and fourth detection signals in accordance further with directions in which the third and fourth displaceable sections are displaced. 
     It is preferable that each of the first and second displacement detectors transmits first to N-th detection signals in accordance with the displacement of each of the first and second displaceable sections, respectively, wherein N is an integer equal to or greater than 2, the controller operates the communication device at first to N-th rates in response to the first to N-th detection signals, respectively. 
     It is preferable that each of the first and second displacement detectors transmits first to N-th detection signals in accordance with the displacement of each of the first and second displaceable sections, respectively, wherein N is an integer equal to or greater than 2, the controller changes what is displayed in the display screen, at first to N-th rates in response to the first to N-th detection signals, respectively. 
     It is preferable that each of the first and second displacement detectors includes a sensor having a wheatstone bridge structure. 
     It is preferable that each of the first and second displacement detector transmits the detection signal only when the displacement of each of the first and second displaceable sections is equal to or greater than a threshold displacement. 
     There is yet further provided a communication device including (a) a device body, (b) at least one operator slidable relative to the device body, (c) a displaceable section which is displaced by the operator, (d) a displacement detector which detects displacement of the displaceable section and transmits a detection signal accordingly, and (e) a controller which operates the communication device in accordance with the detection signal. 
     There is still yet further provided a communication device including (a) a device body, (b) a first operator slidable relative to the device body, (c) a second operator slidable relative to the device body, the first and second operators being formed at opposite sides of the communication device, (d) a first displaceable section which is displaced by the first operator, (e) a second displaceable section which is displaced by the second operator, (f) a first displacement detector which detects displacement of the first displaceable section and transmits a first detection signal accordingly, (g) a second displacement detector which detects displacement of the second displaceable section and transmits a second detection signal accordingly, and (h) a controller which operates the communication device in accordance with at least one of the first and second detection signals. 
     It is preferable that the first and second operators slide in synchronization with each other. 
     It is preferable that the first operator slides in a direction opposite to a direction in which the second operator slides. 
     It is preferable that the first and second operators are slidable independently of each other. 
     It is preferable that the communication device further includes a non-deformable portion fixed to the device body, the first displaceable section being connected to both the first operator and the non-deformable portion, the second displaceable section being connected to both the second operator and the non-deformable portion, the first displacement detector being located across the non-deformable portion and the first displaceable section, the second displacement detector being located across the non-deformable portion and the second displaceable section. 
     It is preferable that the communication device further includes first auxiliary displaceable section being connected to both the first operator and the non-deformable portion, and second auxiliary displaceable section being connected to both the second operator and the non-deformable portion. 
     It is preferable that the first displaceable section is connected to the non-deformable portion at one of upper and lower edges of the non-deformable portion, and the first auxiliary displaceable section is connected to the non-deformable portion at the other edge of the non-deformable portion, and wherein the second displaceable section is connected to the non-deformable portion at one of upper and lower edges of the non-deformable portion at the opposite side to the first displaceable section, and the second auxiliary displaceable section is connected to the non-deformable portion at the other edge of the non-deformable portion at the opposite side to the first auxiliary displaceable section. 
     It is preferable that the communication device further includes a third displacement detector which detects displacement of the first auxiliary displaceable section and transmits a third detection signal accordingly, and a fourth displacement detector which detects displacement of the second auxiliary displaceable section and transmits a fourth detection signal accordingly. 
     It is preferable that the communication device further includes a display screen formed with the body, and wherein the controller changes what is displayed in the display screen, in accordance with at least one of the first and second detection signals. 
     It is preferable that the first and second displacement detector keep transmitting the first and second detection signals while the first and second displaceable sections are kept displaced. 
     It is preferable that the first and second displacement detectors transmit the first and second detection signals in accordance further with directions in which the first and second displaceable sections are displaced. 
     It is preferable that the third and fourth displacement detectors transmit the third and fourth detection signals in accordance further with directions in which the third and fourth displaceable sections are displaced. 
     It is preferable that each of the first and second displacement detectors includes a sensor having a wheatstone bridge structure. 
     It is preferable that each of the first and second displacement detector transmits the detection signal only when the displacement of each of the first and second displaceable sections is equal to or greater than a threshold displacement. 
     In another aspect of the present invention, there is provided a method of operating a communication device, including the steps of (a) displacing a displaceable portion of the communication device, (b) transmitting a control signal in accordance with displacement of the displaceable portion, and (c) operating the communication device in accordance with the control signal. 
     It is preferable that what is displayed in a display screen is changed in accordance with the control signal in the step (c). 
     It is preferable that the control signal is kept transmitted while the displaceable portion is kept displaced. 
     It is preferable that displacement of the displaceable portion is comprised of at least one of a degree of expansion or contraction, a degree of deformation, a degree of angular displacement, and a degree of torsion. 
     It is preferable that the control signal is transmitted in the step (b) in accordance further with a direction in which the displaceable portion is displaced. 
     It is preferable that the method further includes the step of converting the displacement of the displaceable portion into electric energy. 
     It is preferable that first to N-th control signals are transmitted in the step (b) in accordance with the displacement of the displaceable section, wherein N is an integer equal to or greater than 2, the communication device being operated in the step (c) at first to N-th rates in response to the first to N-th control signals, respectively. 
     The above and other objects and advantageous features of the present invention will be made apparent from the following description made with reference to the accompanying drawings, in which like reference characters designate the same or similar parts throughout the drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a front view illustrating a first example of a conventional portable radio-signal communication device. 
     FIG. 2 is a front view illustrating a second example of a conventional portable radio-signal communication device. 
     FIG. 3 is a front view illustrating a third example of a conventional portable radio-signal communication device. 
     FIG. 4 is a front view illustrating a portable radio-signal communication device in accordance with the first embodiment of the present invention. 
     FIG. 5A is a cross-sectional view illustrating an internal structure of the portable radio-signal communication device illustrated in FIG.  4 . 
     FIG. 5B is a cross-sectional view illustrating an internal structure of the portable radio-signal communication device illustrated in FIG. 4 while the communication device is being operated. 
     FIG. 6 is a circuit diagram of a displacement detector used in the communication device illustrated in FIG.  4 . 
     FIG. 7 is a graph showing a characteristic of a displacement detector used in the communication device illustrated in FIG.  4 . 
     FIG. 8 is a flow chart illustrating an operation of the communication device in accordance with the first embodiment. 
     FIG. 9 is a cross-sectional view illustrating a portable radio-signal communication device in accordance with the second embodiment of the present invention in operation. 
     FIG. 10 is a circuit diagram of a displacement detector used in the communication device in accordance with the second embodiment of the present invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     First Embodiment 
     FIG. 4 is a front view of a cellular phone in accordance with the first embodiment of the present invention. FIG. 5A illustrates an internal structure of the cellular phone not in operation, and FIG. 5B illustrates an internal structure of the cellular phone in operation. 
     As illustrated in FIG. 5A, the cellular phone has a device body  1 , and first and second operators  3   a  and  3   b  both having an outer arcuate surface partially extending beyond opposite sides of the device body  1 . As illustrated in FIGS. 4 and 5B, the first and second operators  3   a  and  3   b  are positioned such that when a user holds the cellular phone with his/her hand, his/her fingers naturally make touch with the first and second operators  3   a  and  3   b.    
     The first and second operators  3   a  and  3   b  are located in symmetry with each other about the device body  1 . 
     The first and second operators  3   a  and  3   b  are designed to be rotatable relative to the device body  1 . 
     The device body is formed at opposite sides thereof with first and second cut-outs  1   ka  and  1   kb  each having an inner arcuate surface having the same curvature as a curvature of the arcuate surface of the first and second operators  3   a  and  3   b . The arcuate surfaces of the first and second operators  3   a  and  3   b  are in facing relation to the inner arcuate surface of the first and second cut-outs  1   ka  and  1   kb , and partially project through the first and second cut-outs  1   kb.    
     As illustrated in FIG. 5A, the first and second operators  3   a  and  3   b  are connected to each other through a connecting bar  3   c . The connecting bar  3   c  ensures that the first and second operators  3   a  and  3   b  rotate in synchronization with each other. Accordingly, when the first operator  3   a  rotates in a clockwise direction, for instance, the second operator  3   b  rotates in a counterclockwise direction. 
     It should be noted that the first and second operators  3   a  and  3   b  may be designed to be rotatable independently of each other by not connecting the first and second operators  3   a  and  3   b  through the connecting bar  3   c.    
     The cellular phone further includes first and second supporters  2   a  and  2   b  located inwardly of the first and second operators  3   a  and  3   b , respectively. The first and second supporters  2   a  and  2   b  are fixed to the device body  1 . Each of the first and second supporters  2   a  and  2   b  is designed to have an arcuate outer surface having the same curvature as a curvature of the arcuate surface of the first and second operators  3   a  and  3   b . Thus, the first and second supporters  2   a  and  2   b  can support the first and second operators  3   a  and  3   b  thereon for smooth rotation, respectively. 
     In addition, when a compressive force directed inwardly of the cellular phone is applied to the first and second operators  3   a  and  3   b , the first and second supporters  2   a  and  2   b  act as a stopper to prevent the first and second operators  3   a  and  3   b  from being deformed inwardly of the cellular phone. 
     The cellular phone further includes a deformation detecting unit  9 . The deformation detecting unit  9  is comprised of a rectangular non-deformable body  9 A fixed to the device body  1  by means of a pin  4 , a first deformable section  6   a  connected to both the first operator  3   a  and the non-deformable body  9 A, and deformed by the first operator  3   a , a second deformable section  6   b  connected to both the second operator  3   b  and the non-deformable body  9 A, and deformed by the second operator  3   b , a first auxiliary deformable section  7   a  connected to both the first operator  3   a  and the non-deformable body  9 A, and deformed by the first operator  3   a , a second auxiliary deformable section  7   b  connected to both the second operator  3   b  and the non-deformable body  9 A, and deformed by the second operator  3   b , a first deformation detector  5 A which is located across the non-deformable body  9 A and the first deformable section  6   a , and which detects deformation of the first deformable section  6   a  and transmits a first detection signal accordingly, a second deformation detector  5 B which is located across the non-deformable body  9 A and the second deformable section  6   b , and which detects deformation of the second deformable section  6   b  and transmits a second detection signal accordingly, and a controller  8  which operates the communication device in accordance with the first and second detection signals. 
     The first and second deformable detectors  5 A and  5 B keep transmitting the first and second detection signals while the first and second deformable sections  6   a  and  6   b  are kept deformed. 
     As illustrated in FIG. 5A, the first deformable section  6   a  is connected to the non-deformable body  9 A at a left side and at an upper edge of the non-deformable body  9 A, and the first auxiliary deformable section  7   a  is connected to the non-deformable body  9 A at a left side and at a lower edge of the non-deformable body  9 A. The second deformable section  6   b  is connected to the non-deformable body  9 A at a right side and at an upper edge of the non-deformable body  9 A, and the second auxiliary deformable section  7   b  is connected to the non-deformable body  9 A at a right side and at a lower edge of the non-deformable body  9 A. 
     Though not illustrated, the communication device may be designed to further include a third deformation detector which is located across the non-deformable body  9 A and the first auxiliary deformable section  7   a , and which afetects deformation of the first auxiliary deformable section  7   a  and transmits a third detection signal accordingly, and a fourth deformation detector which is located across the non-deformable body  9 A and the second auxiliary deformable section  7   b , and which detects deformation of the second auxiliary deformable section  7   b  and transmits a fourth detection signal accordingly. 
     As illustrated in FIG. 5B, when the first and second operators  3   a  and  3   b  are made to rotate, the non-deformable body  9 A is kept non-deformed. When the first and second operators  3   a  and  3   b  are made to rotate, the first and second deformable sections  6   a  and  6   b  and the first and second auxiliary deformable sections  7   a  and  7   b  follow the first and second operators  3   a  and  3   b . As a result, stress is concentrated at proximal ends of the first and second deformable sections  6   a  and  6   b  and the first and second auxiliary deformable sections  7   a  and  7   b , and thus, the proximal ends of the sections  6   a ,  6   b ,  7   a  and  7   b  are made deformed. 
     Specifically, when the first and second operators  3   a  and  3   b  are made to rotate in a clockwise direction indicated with an arrow M, a shrinkage force exerts on the first deformation detector  5 A, and a tensile force exerts on the second deformation detector  5 B. 
     The first and second deformation detectors  5 A and  5 B convert displacement thereof caused by the shrinkage and tensile forces, into electric energy, and transmits the first and second detection signals accordingly. 
     When the first and second operators  3   a  and  3   b  are made to rotate, the controller  8  incorporated in the device body  1  and connected to the first and second operators  3   a  and  3   b  detects an angular moment generated by the first and second operators  3   a  and  3   b , as displacement of the first and second deformable portions  6   a  and  6   b , based on the first and second detection signals transmitted from the first and second deformation detectors  5 A and  5 B. 
     The controller  8  accomplishes one of functions of the cellular phone in accordance with the thus detected angular moment. For instance, the controller  8  scrolls what is displayed in a display screen  1 A (see FIG. 4) in accordance with a magnitude of the detected angular moment. If the detected angular moment is positive in a direction or if the first and second operators  3   a  and  3   b  are made to rotate in a clockwise direction, what is displayed in the display screen  1 A is upwardly scrolled, whereas if the detected angular moment is negative in a direction or if the first and second operators  3   a  and  3   b  are made to rotate in a counterclockwise direction, what is displayed in the display screen  1 A is downwardly scrolled. 
     FIG. 6 is a circuit diagram of a circuit included in the controller  8 . The illustrated circuit has a wheatstone bridge structure. 
     In the circuit illustrated in FIG. 6, it is assumed that there is generated an output voltage VO between c and d, when a voltage VE is applied across a and b. As the first and second deformable sections  6   a  and  6   b  are deformed, resistances of the first and second deformation detectors  5 A and  5 B vary, resulting in that the output voltage VO between c and d also varies. By measuring the output voltage VO, it is possible to measure a force exerting on the first and second operators  3   a  and  3   b.    
     As illustrated in FIG. 5B, the first and second deformation detectors  5 A and  5 B are deformed in opposite directions. Hence, the controller  8  could have better sensitivity than that of a controller including only one deformation detector. 
     As illustrated in FIG. 7, variation □V of the output voltage VO is in proportion to a force F exerting on the controller  8 . For instance, if it is assumed that when an angular moment M is applied to the first and second operators  3   a  and  3   b  in a clockwise direction, the variation □V is positive, when an angular moment (−M) is applied to the first and second operators  3   a  and  3   b  in a counterclockwise direction, the variation □V is negative. 
     FIG. 8 is a flow chart showing an operation of the cellular phone in accordance with the first embodiment. 
     When the cellular phone is powered on in step S 1 , the first and second deformation detectors  5 A and  5 B start detecting deformation of the first and second deformable sections  6   a  and  6   b  in step S 2 . 
     When the controller  8  detects the variation □V of the output voltage VO, the controller  8  checks whether an absolute value of the variation □V is equal to or greater than a predetermined threshold voltage Vth, in step S 3 . 
     If the absolute value of the variation □V is smaller than a predetermined threshold voltage Vt (NO in step S 3 ), the controller  8  repeats the step S 3 . 
     If the absolute value of the variation □V is equal to or greater than a predetermined threshold voltage Vt (YES in step S 3 ), the controller  8  then checks whether the variation □V is positive or negative, in step S 4 . 
     If the variation □V is positive (YES in step S 4 ), the controller  8  upwardly scrolls what is displayed in the display screen  1 A, in step S 5 . 
     If the variation □V is negative (NO in step S 4 ), the controller  8  downwardly scrolls what is displayed in the display screen  1 A, in step S 6 . 
     As explained above, when a force equal to or greater than a force corresponding to the threshold voltage Vth is applied to the first and second operators  3   a  and  3   b , what is displayed in the display screen  1 A is successively scrolled. Hence, a user does no longer have to push the operation keys  81  or  91  many time unlike the conventional cellular phones illustrated in FIGS. 1 and 2. 
     Though the comparison between the variation □V and the threshold voltage Vth in step S 3  is carried out by the controller  8  in the first embodiment, the comparison may be carried out by a micro-processor generally equipped in a cellular phone. The threshold voltage Vth is experimentally or theoretically calculated in advance, and is stored in a memory equipped in the cellular phone. 
     The above-mentioned first embodiment provides advantages as follows. 
     First, since the variation □V can be kept generated if the first and second operators  3   a  and  3   b  are kept rotated, , a user can readily operate the cellular phone while a user naturally holds the cellular phone. 
     Second, since the first and second operators  3   a  and  3   b  are located in symmetry with each other, a user can operate the first and second operators  3   a  and  3   b  with either a right or left hand. 
     In the above-mentioned first embodiment, though each of the first and second deformation detectors  5 A and  5 B is designed to transmit a constant detection signal, they may be designed to transmit a varying detection signal. For instance, each of the first and second deformation detectors  5 A and  5 B may transmit first to N-th detection signals in accordance with a degree of deformation of each of the first and second deformable sections  6   a  and  6   b , respectively. Herein, N is an integer equal to or greater than  2 . 
     In the above-mentioned case, the controller  8  changes what is displayed in the display screen  1 A at first to N-th rates in response to the first to N-th detection signals, respectively. 
     Second Embodiment 
     FIG. 9 illustrates an internal structure of a cellular phone in accordance with the second embodiment. 
     As illustrated in FIG. 9, the cellular phone has a device body (not illustrated), and first and second operators  73   a  and  73   b  both designed to be slidable along opposite sides of the device body. The first and second operators  73   a  and  73   b  are positioned such that when a user holds the cellular phone with his/her hand, his/her fingers naturally make touch with the first and second operators  73   a  and  73   b.    
     The first and second operators  73   a  and  73   b  are located in symmetry with each other about the device body  1 . 
     The cellular phone further includes a deformation detecting unit  9 . The deformation detecting unit  9  is comprised of a rectangular non-deformable body  9 A fixed to the device body by means of a pin, a first deformable section  6   a  connected to both the first operator  73   a  and the non-deformable body  9 A, and deformed by the first operator  73   a , a second deformable section  6   b  connected to both the second operator  73   b  and the non-deformable body  9 A, and deformed by the second operator  73   b , a first auxiliary deformable section  7   a  connected to both the first operator  73   a  and the non-deformable body  9 A, and deformed by the first operator  73   a , a second auxiliary deformable section  7   b  connected to both the second operator  73   b  and the non-deformable body  9 A, and deformed by the second operator  73   b , a first deformation detector  5 A which is located across the non-deformable body  9 A and the first deformable section  6   a , and which detects deformation of the first deformable section  6   a  and transmits a first detection signal accordingly, a second deformation detector  5 B which is located across the non-deformable body  9 A and the second deformable section  6   b , and which detects deformation of the second deformable section  6   b  and transmits a second detection signal accordingly, a third deformation detector  5 C which is located across the non-deformable body  9 A and the first auxiliary deformable section  7   a , and which detects deformation of the first auxiliary deformable section  7   a  and transmits a third detection signal accordingly, a fourth deformation detector  5 D which is located across the non-deformable body  9 A and the second auxiliary deformable section  7   b , and which detects deformation of the second auxiliary deformable section  7   b  and transmits a fourth detection signal accordingly, and a controller which operates the communication device in accordance with the first to fourth detection signals. 
     The first to fourth deformable detectors  5 A to  5 D keep transmitting the first to fourth detection signals while the first and second deformable sections  6   a  and  6   b  and the first and second auxiliary deformable sections  7   a  and  7   b  are kept deformed. 
     In the second embodiment, since the first and second operators  3   a  and  3   b  are connected to each other through the deformation detecting unit  9 , the first and second deformable sections  6   a  and  6   b  and the first and second auxiliary deformable sections  7   a  and  7   b  are deformed in synchronization with each other, but in opposite directions. 
     As illustrated in FIG. 9, the first deformable section  6   a  is connected to the non-deformable body  9 A at a left side and at an upper edge of the non-deformable body  9 A, and the first auxiliary deformable section  7   a  is connected to the non-deformable body  9 A at a left side and at a lower edge of the non-deformable body  9 A. The second deformable section  6   b  is connected to the non-deformable body  9 A at a right side and at an upper edge of the non-deformable body  9 A, and the second auxiliary deformable section  7   b  is connected to the non-deformable body  9 A at a right side and at a lower edge of the non-deformable body  9 A. 
     In brief, the cellular phone in accordance with the second embodiment is structurally different from the cellular phone in accordance with the first embodiment in that the first and second operators  3   a  and  3   b  are replaced with the first and second operators  73   a  and  73   b . Since the first and second operators  73   a  and  73   b  are in the form of a flat plate, it is not necessary for the cellular phone in accordance with the second embodiment to have the supporters  2   a  and  2   b  and the cut-outs  1   ka  and  1   kb.    
     In the cellular phone illustrated in FIG. 9, the controller detects vertical displacement of the first and second operators  73   a  and  73   b  which is made when a force Fa is applied to the first operator  73   a . 
     In the cellular phone illustrated in FIG. 9, when a user upwardly slides the first operator  73   a  with a thumb  78  by a certain length, the second operator  73   b  is downwardly slid with an index finger  79  by the same length in synchronization with the first operator  73   a . To the contrary, when a user upwardly slides the second operator  73   b  with an index finger  79  by a certain length, the first operator  73   a  is downwardly slid with a thumb  78  by the same length in synchronization with the second operator  73   b.    
     It should be noted that the first and second operators  73   a  and  73   b  may be designed to slide independently of each other to thereby make different displacements from each other. 
     FIG. 10 is a circuit diagram of a circuit constituted by the first to fourth deformation detectors  5 A to  5 D. The illustrated circuit has a wheatstone bridge structure like the circuit illustrated in FIG.  6 . In the second embodiment, since the facing first and second deformation detectors  5 A to  5 B are deformed in opposite directions, and in addition, the facing first and second auxiliary deformation detectors  5 C to  5 D are deformed in opposite directions, the circuit can have higher sensitivity than that of the circuit illustrated in FIG. 6, and hence, can detect displacements of the first and second operators  73   a  and  73   b  more accurately than the circuit illustrated in FIG.  6 . 
     As having been illustrated in FIG. 7, the variation □V of the output voltage VO is in proportion to a force F applied to the first and second operators  73   a  and  73   b . By determining a plurality of threshold voltages, it would be possible to gradually change a rate at which what is displayed in the display screen  1 A is scrolled. That is, if a greater force is applied to the first and second operators  73   a  and  73   b , what is displayed in the display screen  1 A is scrolled at a greater rate, and to the contrary, if a smaller force is applied to the first and second operators  73   a  and  73   b , what is displayed in the display screen  1 A is scrolled at a smaller rate. 
     While the present invention has been described in connection with certain preferred embodiments, it is to be understood that the subject matter encompassed by way of the present invention is not to be limited to those specific embodiments. On the contrary, it is intended for the subject matter of the invention to include all alternatives, modifications and equivalents as can be included within the spirit and scope of the following claims. 
     The entire disclosure of Japanese Patent Application No. 11-105921 filed on Apr. 13, 1999 including specification, claims, drawings and summary is incorporated herein by reference in its entirety.