United States Patent [19J
`Norimatsu
`
`[54) TELEPHONE HAVING TOUCH SENSOR
`FOR RESPONDING TO A CALL
`
`Inventor: Hidehiko Norimatsu, Tokyo, Japan
`[75]
`[73] Assignee: NEC Corporation, Tokyo, Japan
`[21] Appl. No.: 998,652
`
`[22] Filed:
`
`Dec. 29, 1992
`
`[56)
`
`Related U.S. Application Data
`[63) Continuation of Ser. No. 474,910, Feb. 5, 1990, aban(cid:173)
`doned.
`Foreign Application Priority Data
`[30)
`Feb. 3, 1989 [JP]
`Japan .................................... 1-23713
`Int. Cl.s ............................................ H04M 11/00
`[51)
`[52) u.s. Cl ......................................... 379/58; 379/61;
`200/DIG. 2; 341/22
`[58) Field of Search ....................... 379/57, 58, 96, 61;
`200/DIG. 2; 341/22, 33, 34; 340/562
`References Cited
`U.S. PATENT DOCUMENTS
`3,668,659 6/1972 Hutchings .
`3,705,424 12/1972 Harvey, Jr ............... 200/DIG. 2 X
`3,728,501 4/1973 Larson et al. ............ 200/DIG. 2 X
`3,737,670 6/1973 Larson ...................... 200/DIG. 2 X
`3,811,054 5/1974 Wernet al. ..................... 340/562 X
`3,944,843 3/1976 Vaz Martins ............ 200/DIG. 2 X
`4,237,421 12/1980 Waldron ......................... 340/562 X
`4,281,323 7/1981 Burnett et al. .................... 341/33 X
`4,550,310 10/1985 Yamaguchi et al. ............. 341/33 X
`4,567,470 1/1986 Yoshikawa et al. .................. 341/33
`4,651,133 3/1987 Ganesan et al ................... 341/33 X
`4,725,817 2/1988 Wihlborg .............................. 341/34
`4,827,085 5/1989 Yaniv et al. ...................... 379/96 X
`4,831,279 5/1989 Ingraham ........................ 340/562 X
`4,848,887 7/1989 Suzuki et al. ......................... 379/58
`
`lllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllll
`5,329,577
`Jul. 12, 1994
`
`US005329577A
`[II] Patent Number:
`[45] Date of Patent:
`
`4,870,676 9/1989 Leno ..................................... 379/58
`4,870,696 9/1989 Yorita ............................... 379/57 X
`
`FOREIGN PATENT DOCUMENTS
`0213929 11/1987 European Pat. Off ..
`0283853 9/1988 European Pat. Off ..
`0100381 8/1981 Japan ................................... 340/562
`0153342 9/1984 Japan ..................................... 379/61
`0229432 11/1985 Japan ..................................... 379/61
`61-171230 8/1986 Japan .
`62-3546 1/1987 Japan .
`8503820 2/1985 PCT Int'l Appl ..
`2040524 8/1980 United Kingdom ................ 340/562
`
`OTHER PUBLICATIONS
`Patent Abstracts of Japan, vol. 11, No. 171
`(E-512)(2618) Jun. 2, 1987.
`Patent Abstracts of Japan, vol. 10, No. 379
`(E-465)(2436) Dec. 18, 1986.
`Primary Examiner-James L. Dwyer
`Assistant Examiner-Magdy Shehata
`Attorney, Agent, or Firm-Sughrue, Mion, Zinn,
`Macpeak & Seas
`
`ABSTRACT
`[57]
`The telephone includes a touch sensor which may be
`attached on a handset. When the telephone receives a
`call meant therefor, the telephone alerts the user to the
`call by outputting a ringing tone through a speaker. In
`response to the call, the telephone also transmits a sig(cid:173)
`naling tone to a base station which may be connected to
`the telephone over a radio channel and to a public
`switching telephone network. If the user touches the
`touch sensor in response to the ringing tone, the tele(cid:173)
`phone stops the signaling tone and thus informs the base
`station that the user has responded to the call.
`
`28 Claims, 3 Drawing Sheets
`
`42
`
`43
`
`~
`40 HANDSET
`
`MICROSOFT EXHIBIT 1006
`
`

`

`U.S. Patent
`
`July 12, 1994
`
`Sheet 1 of 3
`
`5,329,577
`
`FIG. 1
`
`13
`
`II
`
`15
`
`16 RECEIVER
`
`17 MICROPHONE
`
`18 SPEAKER
`
`19
`
`TOUCH
`~-----.--.1SENSOR
`
`'--------1~ TOUCH-TONE
`PANEL
`
`20
`
`FIG. 4
`
`42
`
`43
`
`~
`40 HANDSET
`
`

`

`U.S. Patent
`
`July 12, 1994
`
`Sheet 2 of 3
`
`5,329,577
`
`WAITING
`
`RECEIVE 10 SIGNAL?
`
`TRANSMIT RESPONSE SIGNAL
`
`NO
`
`RECEIVE S-CH DESIGNATE SIGNAL?
`
`RECEIVE ALERT SIGNAL ?
`
`GENERATE RINGING TONE
`TRANSMIT SIGNALLING TONE
`
`57
`
`IS TALK START KEY PRESSED?~~
`0
`S9
`YES
`HANDSET IS PICKED UP ?
`
`NO
`
`DETECT TOUCH SIGNAL?
`
`CONVERSATION
`
`512
`
`FIG. 2
`
`

`

`U.S. Patent
`
`July 12, 1994
`
`Sheet 3 of 3
`
`5,329,577
`
`FIG. 3
`
`J19A TOUCH SENSOR
`
`r---------------,
`,~ 501 OSCILLATOR
`lb r-
`I
`I
`I
`I
`~'
`I
`~~
`{t51
`Ia ,-1
`I
`511-' L::.J
`I
`l
`I
`I
`
`521
`
`502
`
`503
`
`505
`
`541
`
`I
`I
`1
`53n
`533
`532
`531
`I
`I
`L----------------~
`T
`
`f - - - - - - -11 li----
`:, ...... - ...... :L
`l r
`
`1
`
`I ·
`I
`I
`I
`
`I
`
`REF.
`VALUE
`
`I
`
`I
`I
`I
`I
`
`I
`, . . ; -1 ! -
`i I
`~-=_-::-t Vur
`..,11~ r
`''u
`
`FIG. 6A
`
`FIG. 68
`
`531 INPUT -.-oil
`.. 1 W''
`
`5321NPUT
`
`FIG. 6C
`
`FIG. 60
`
`FIG. 6E
`
`53n INPUT l
`:
`...__ _ _,
`_jr------.1 i
`Vor *-:M
`t· II
`~~,~
`
`53n INPUT
`
`541
`
`1 1
`
`

`

`1
`
`5,329,577
`
`2
`FIG. 4 is a perspective view of a handset on which
`the touch sensor shown in FIG. 3 is provided;
`FIG. 5 is a schematic circuit diagram of another
`touch sensor to be used in the FIG. 1 telephone; and
`FIGS. 6A to 6E are used to show the operation of
`touch sensor 19B shown in FIG. 5.
`
`TELEPHONE HAVING TOUCH SENSOR FOR
`RESPONDING TO A CALL
`
`This is a continuation of application Ser. No. 5
`07/474,910 filed Feb. 5, 1990 now abandoned.
`
`BACKGROUND OF THE INVENTION
`The present invention relates to a telephone and,
`more particularly, to a telephone suitable for a mobile 10
`telephone system.
`In a conventional telephone the user responds to a
`telephone call by picking up a handset or pressing a talk
`start button.
`In the case of picking up the handset, a hook switch 15
`of the telephone is closed to inform a telephone ex(cid:173)
`change, which in a mobile telephone system may be
`connected to the telephone through a mobile base sta(cid:173)
`tion, that the user of the telephone has responded to the
`call. If the user wants to use the telephone as a hands- 20
`free telephone, however, he does not need the handset;
`nevertheless, he must pick it up to connect the call.
`Similarly, upon pressing the talk start button, the
`telephone informs the telephone exchange that the user
`has responded to a call. In this case, however, the user 25
`must search for the talk start button among many but(cid:173)
`tons provided on the telephone. This may hinder driv(cid:173)
`ing when the telephone is used in a vehicle.
`
`SUMMARY OF THE INVENTION
`An object of the present invention is, therefore, to
`provide an improved telephone which has a touch sen(cid:173)
`sor to respond to a call.
`Another object of the present invention is to provide 35
`a telephone in which the user can easily respond to a
`call by simply touching the telephone.
`Yet another object of the present invention is to pro(cid:173)
`vide a telephone having a touch sensor to respond to a
`call in addition to a talk start button and to a hook 40
`switch.
`Still yet another object of the present invention is to
`provide a telephone suitable for a mobile telephone
`system, which eliminates any trouble in responding to a
`call, while the user drives a vehicle in which the tele- 45
`phone is installed.
`According to the present invention, there is provided
`a telephone comprising a speaker for annunciating a call
`meant for the telephone. The telephone also comprises
`a touch sensor which includes a sensor portion and 50
`detects whether the sensor portion is touched or not.
`Upon detecting a touch on the touch sensor, the tele(cid:173)
`phone informs a telephone exchange that the user has
`responded to the call. The exchange then connects the
`telephone to a calling party telephone from which the 55
`call originated.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`Above and other objects, features and advantages of
`the present invention will become more apparent from 60
`the following description referring to the accompany(cid:173)
`ing drawings in which:
`FIG. 1 is a block diagram showing a mobile tele(cid:173)
`phone embodying the present invention;
`FIG. 2 is a flow-chart showing the operation of the 65
`FIG. 1 telephone;
`FIG. 3 shows a schematic circuit diagram of a touch
`sensor to be used in the FIG. 1 telephone;
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENTS
`In FIG. 1, a mobile telephone 10 is shown which may
`be used for a mobile telephone system. The mobile
`telephone 10 may be connected over a radio channel to
`a mobile base station which in tum may be connected to
`a telephone exchange included in a public switching
`telephone network (PSTN).
`The mobile telephone 10 includes an antenna 11 for
`picking up a radio signal transmitted from the mobile
`base station (not shown). The antenna 11 is also used for
`transmitting a radio signal to the mobile base station.
`The antenna 11 is connected to both a transmitter 13
`and a receiver 14 through an antenna duplexer 12. The
`transmitter 13 receives a speech, or voice, signal and a
`control signal from a controller 15 through conductor
`lines 131 and 132, respectively. The transmitter 13 mod(cid:173)
`ulates a radio frequency signal with the received speech
`signal and control signal and transmits the modulated
`signal to the base station through the antenna duplexer
`12 and antenna 11.
`The receiver 14 receives a radio frequency signal
`30 from the base station through the antenna 11 and an(cid:173)
`tenna duplexer 12. The receiver 14 demodulates the
`received signal to provide the demodulated speech and
`control signals to the controller 15 through conductor
`lines 141 and 142, respectively. The controller 15
`changes the channel frequencies of transmitter 13 and
`receiver 14 through a conductor line 151. The control-
`ler 15 may be composed of a commercially available
`microprocessor. The antenna 11, antenna duplexer 12,
`transmitter 13 and receiver 14 are well-known in the art
`and thus no further description of them will be given.
`The mobile telephone 10 further comprises a receiver
`16, microphone 17 and speaker 18 which are coupled to
`the controller 15. The receiver 16 and microphone 17
`are used for a telephone conversation. The speaker 18 is
`used for annunciating a call to the user by outputting a
`ringing tone which is generated in the controller 15 in
`response to an alert signal, as will be described later.
`The receiver 16 and speaker 18 may be accommodated
`in an earpiece of a handset. The microphone 17 may be
`accommodated in a mouthpiece of the handset.
`The telephone 10 includes a touch-tone panel 20 for
`dialing. The panel 20 may include a key pad and a dis(cid:173)
`play. The telephone also includes a touch sensor 19
`which detects whether or not the user touches the tele(cid:173)
`phone 10 in response to the ringing tone, i.e., in response
`to a call meant for him. By using the touch sensor 19,
`the user can respond to the call without resorting to
`picking up the handset or to pressing any key. It is to be
`noted that the user may also respond to a call by picking
`up the handset or by pressing a talk start key as in the
`prior art.
`Referring to FIG. 2, the operation of the controller
`15 as shown in FIG. 1 will now be described in more
`detail. In a waiting state (step S1), the controller 15
`causes the transmitter 13 and receiver 14 to tune to a
`paging channel over which a calling signal is transmit-
`ted from the mobile base station. The calling signal may
`include an identification (ID) number of the mobile
`
`

`

`5,329,577
`
`55
`
`f= 1/(2nlit+tD+tu)
`
`The falling and rising times tD and tuare represented as
`follows:
`
`4
`3
`In FIG. 4, a handset 40 includes a sensor portion 191
`telephone 10. If the telephone 10 receives the calling
`attached on part of its surface. The handset 40 also
`signal, i.e., the controller 15 detects the ID number of
`includes a touch-tone panel having a key pad 41 and a
`telephone 10 at step S2, the controller 15 transmits a call
`response signal to the base station at step S3. In response
`display 42. The handset 40 further includes an earpiece
`to reception of the response signal, the base station 5 44 and mouthpiece 45. The earpiece may accommodate
`the receiver 16 and the speaker 18 (see FIG. 1). The
`transmits a speech-channel designate signal which rep-
`resents a speech channel designated to the telephone 10
`mouth-piece 45 may accommodate the microphone 17
`for conversation.
`(FIG. 1). The handset 40 may electrically be connected
`If the controller 15 receives the speech-channel des-
`to the controller 15 through a cord 43. The sensor por-
`ignate signal at step S4, the controller 15 proceeds to 10 tion, or mesh, 191 is attached to part of the handset
`surface, which part is so selected that the user can most
`step S5. Otherwise, the controller 15 returns back to
`step S2. At step S5, the controller 15 causes the trans-
`conveniently touch thereon.
`mitter 13 and receiver 14 to tune to the designated
`The touch sensor portion 191 may be attached to any
`speech channel. On this speech channel, the telephone
`part of a vehicle in which the mobile telephone 10 is
`10 waits at step S6 for an alert signal which makes the 15 installed. For example, the sensor portion 191 may be
`provided on the surface of a steering wheel.
`controller 15 generate a ringing tone, and causes the
`speaker 18 to output the ringing tone (see step S7).
`In FIG. 5, another touch sensor 19B is shown which
`If the controller 15 receives the alert signal, it trans-
`includes an oscillator 501, counter 502 and comparator
`mits a signaling tone (ST) to the base station (also see
`503. The oscillator 501 includes n cascaded inverters
`step S7). The ST informs the base station that the tele- 20 53/-53n (n is the positive odd integer), sensor portion
`phone 10 is annunciating a call to the user. When a talk
`511 and resistor 521 which is connected between the
`start key in the touch-tone panel is pressed at step S8,
`input of inverter 531 and the output of inverter 53n. The
`the controller 15 moves on to step Sll at which the ST
`sensor portion 511 includes a capacitor 51 having two
`is stopped. If the talk start key is not pressed, step S8 is
`conductive plates 1a and 1b which are connected to
`followed by step S9 at which the controller 15 sees if a 25 ground and the input of inverter 531, respectively. If the
`handset is picked up. If the answer is affirmative, the
`user touches the plate 1a, the capacitance C of capacitor
`operation proceeds to step S11. If it is negative, the
`51 increases. The plate 1a may be provided on the sur-
`operation moves on to step S10 at which the controller
`face of handset 40 as the sensor portion 191 (FIGS. 3
`15 monitors the output of touch sensor 19.
`and 4). Or the plate 1a may be attached to a steering
`If the touch sensor 19 produces a detection signal 30 wheel of a vehicle in which the telephone is used. The
`capacitor 51 and resistor 521 constitute a filter whose
`indicating that the user touches the sensor 19, i.e., he
`responds to the call, the controller 15 goes on to step
`time constant is determined by the resistance R of resis-
`S11. Otherwise, the operation returns back to step S8.
`tor 521 and the capacitance C.
`In response to the stoppage of ST, the mobile base sta-
`The operation of the touch sensor 19B will now be
`tion connects the mobile telephone 10 and a calling 35 described referring to FIGS. 6A-6E. FIG. 6A shows an
`party for conversation. After step S11, the mobile tele-
`input waveform applied to the inverter 531 and FIG.
`6B, an input waveform applied to the inverter 532. The
`phone user enters conversation with the calling party
`(step S12). The operation after step S12 is the same as
`waveform of FIG. 6B is delayed from the waveform of
`FIG. 6A by ~t. Likewise, each input waveform is de-
`usual mobile telephone system and, therefore, such
`40 layed from the previous waveform by ~t, as shown in
`operation will be omitted in this specification.
`FIGS. 6c and 60. The output (FIG. 6D) of inverter
`In FIG. 3, a touch sensor 19A includes a sensor por-
`tion 191, resistors 192 and 193 and an operational ampli-
`53n passes the filter including the resistor 521 and the
`capacitor 51. FIG. 6E shows the output waveform of
`fier 194. The sensor portion 191 is composed of conduc-
`the filter which has a falling time tDand a rising time tu.
`tive thin lines 911 and 912 which constitute a mesh and
`may be attached to a handset as will be described refer- 45 These times tD and tu are determined by the time con(cid:173)
`ring to FIG. 4. The resistor 192 is connected between
`stant of the filter and by the threshold levels V DTand
`one end of the line 911 and a terminal 195 to which a
`V UT of inverter 531.
`high voltage source V DD is applied. The resistor 193 is
`As can be seen from FIGS. 6A-6E, the period T of
`connected between one end of the line 912 and a non-
`50 oscillation output is given by
`inverted terminal of amplifier 194. An inverted terminal
`of amplifier 194 is connected to a terminal196 to which
`a reference voltage V REF is applied. The output of am(cid:173)
`plifier 194 is provided to the controller 15 (FIG. 1).
`The lines 911 and 912 are electrically separated from
`each other. When the user touches the sensor portion
`191, the lines 911 and 912 are electrically connected to
`each other. As a result, a high voltage is applied to the
`non-inverted terminal of amplifier 194 from the terminal
`195 through the resistor 192 and lines 911 and 912. The
`high voltage is set to be higher than the reference volt- 60
`age V REF· Thus, when the user touches the sensor por(cid:173)
`tion 191, the amplifier 194 produces a high-level signal
`which is sent to the controller 15 as a detection signal.
`Otherwise, the amplifier 194 produces a low-level sig(cid:173)
`nal. As mentioned earlier, in response to the detection 65
`signal, the controller 15 determines that the user has
`responded to a call and then stops the transmission of
`the signaling tone.
`
`Thus, the oscillation frequency f of oscillator 501 is
`written as
`
`ID=-CR In VDT
`
`tu=-CR In (1-Vur)
`
`Then the frequency f will become
`
`f=l/[2nlit-CR In VDr(I-Vur)]
`
`

`

`5,329,577
`
`5
`where V DT and V UT are smaller than one and thus
`-CR In V nr(l-Vur) is always positive. Therefore, if
`the capacitance C is changed, the oscillation frequency
`f can be changed. In other words, if the user touches the
`sensor portion 511, the capacitance C increases and thus 5
`the frequency f decreases.
`The oscillation frequency f of oscillator 501 is
`counted by the counter 502. The counted number is
`applied to the comparator 503 through a parallel bus.
`The comparator 503 compares the counted number 10
`with a reference number applied thereto from a terminal
`504 through a parallel bus. The comparator 503 pro(cid:173)
`vides a high-level output to the controller 15 (FIG. 1)
`when the counted number is smaller than the reference
`number; i.e., the user touches the sensor portion 511. 15
`Otherwise, the comparator 503 provides a low-level
`output to the controller 15. The comparator 503 may be
`composed of a device of j.LPD4063B manufactured and
`marketed by NEC.
`What is claimed is:
`1. A telephone comprising:
`first means for annunciating a call meant for said
`telephone;
`a touch sensor portion;
`second means for detecting whether said touch sen- 25
`sor portion is touched or not and for producing a
`detection signal when said touch sensor portion is
`touched; and
`third means responsive to said detection signal for
`causing said telephone to respond to said call only 30
`after the annunciation of said call.
`2. A telephone as claimed in claim 1, wherein said
`annunciating means comprises means for generating a
`ringing tone and speaker means for outputting said ring(cid:173)
`ing tone.
`3. A telephone as claimed in claim 1, wherein said
`touch sensor portion comprises two conductive thin
`lines which are electrically separated from each other
`and constitute a mesh, one of said lines being connected
`to a voltage source, and wherein said second means 40
`comprises an operational amplifier having a non(cid:173)
`inverted input terminal and or inverted input terminal
`which are connected to the other of said lines and to a
`reference voltage source, respectively, the output of
`said amplifier being outputted as said detection signal. 45
`4. A telephone as claimed in claim 3, further compris(cid:173)
`ing a handset having a surface, said mesh being attached
`to part of said surface.
`5. A telephone as claimed in claim 1, further compris-
`ing:
`transmitter means coupled to said first and third
`means for transmitting a radio frequency signal
`which is modulated with a speech signal and a
`control signal; and
`receiver means coupled to said first and third means 55
`for receiving a radio frequency signal which is
`modulated with a speech signal and a control sig(cid:173)
`nal.
`6. A telephone as claimed in claim 5, wherein said
`telephone is installed in a vehicle having a steering 60
`wheel, and wherein said touch sensor portion is at(cid:173)
`tached to said steering wheel.
`7. A mobile telephone comprising:
`means for detecting a calling signal meant for said
`mobile telephone to produce a first detection sig- 65
`nal;
`means responsive to said first detection signal for
`transmitting a response signal;
`
`6
`means for recetvmg a speech-channel designation
`signal which is transmitted from a base station in
`response to said response signal and which desig(cid:173)
`nates a speech channel to said mobile telephone to
`produce a received channel designation signal;
`means responsive to said received channel designa-
`tion signal for tuning said mobile telephone to said
`speech channel;
`means for receiving an alert signal to produce a re(cid:173)
`ceived alert signal;
`means response to said received alert signal for pro(cid:173)
`ducing a ringing tone;
`means response to said received alert signal for trans(cid:173)
`mitting a signaling tone;
`touch sensor means for producing a touch signal
`when being touched;
`meatts for detecting said touch signal to produce a
`second detection signal; and
`means responsive to said second detection signal for
`stopping the transmission of said signaling tone
`only after the reception of said alert signal.
`8. A telephone comprising:
`first means for detecting a call;
`second means responsive to the output of said first
`means for producing an annunciate signal;
`third means having a sensor portion for producing a
`touch signal when said sensor portion is touched;
`and
`fourth means responsive to said touch signal for re(cid:173)
`sponding to said call, only after the production of
`said annunciation signal.
`9. A telephone as claimed in claim 8, further compris(cid:173)
`ing a handset having a surface, wherein said sensor
`35 portion comprises a mesh attached to part of said sur(cid:173)
`face.
`10. A telephone as claimed in claim 8, wherein said
`telephone is installed in a vehicle having a steering
`wheel, and wherein said sensor portion is attached to
`said steering wheel.
`11. A telephone as claimed in claim 8, wherein said
`sensor portion comprises first and second conductive
`lines which are electrically separated from each other
`and constitute a mesh, and wherein said third means
`comprises a high voltage source connected to said first
`conductive line and an operational amplifier having
`non-inverted and inverted inputs which are connected
`to said second conductive line and to a reference volt(cid:173)
`age source, respectively, for outputting an output as
`said touch signal when a voltage applied to said non(cid:173)
`inverted input is higher than the voltage of said refer(cid:173)
`ence voltage source.
`12. An apparatus comprising:
`means for communicating with other parties;
`means connected to said communicating means for
`annunciating a reception of a call;
`touch sensor means for sensing human being's touch
`thereon; and
`means responsive to the output of said touch sensor
`means for making said apparatus respond to said
`call only after the annunciation of reception of said
`call.
`13. An apparatus as claimed in claim 12, wherein said
`communicating means comprises a receiver and a mi(cid:173)
`crophone for telephone conversation; and a handset for
`accommodating said receiver and microphone, and
`wherein said touch sensor means is attached to the sur(cid:173)
`face of said handset.
`
`20
`
`50
`
`

`

`5,329,577
`
`5
`
`20
`
`25
`
`8
`producing a second detection signal when a touch
`sensor is touched; and
`responsive to said second detection signal, stopping
`the transmission of said signaling tone only after
`the reception of said alert signal.
`22. A method as claimed in claim 21, further compris(cid:173)
`ing the steps of:
`producing a third detection signal when a particular
`key is pressed; and
`responsive to said third detection signal, stopping the
`transmission of said signaling tone.
`23. A telephone as claimed in clam 1, further compris(cid:173)
`ing a handset, wherein said touch sensor portion com(cid:173)
`prises a capacitor having two conductive plates one of
`which is attached to the surface of said handset, and the
`other of which is attached to a ground potential.
`24. A telephone as claimed in claim 1, wherein said
`touch sensor portion comprises a capacitor having two
`conductive plates, and wherein said second means com(cid:173)
`prises an oscillator in which said capacitor is included;
`a counter for counting the output frequency of said
`oscillator to produce a counted number; and a compara(cid:173)
`tor for comparing said counted number with a reference
`number to produce an output as said detection signal.
`25. An apparatus as claimed in claim 12, wherein said
`touch sensor means comprises oscillator means includ(cid:173)
`ing a capacitor which has two conductive plates for
`generating an oscillation signal whose frequency is
`changed by human being's touch on one of said two
`conductive plates; counter means for counting the fre(cid:173)
`quency of said oscillation signal to produce a counted
`number; comparator means for comparing said counted
`number with a reference number to produce an output
`as said output of said touch sensor means.
`26. An apparatus as claimed in claim 25, further com(cid:173)
`prising a handset, wherein one of said conductive plates
`is connected to ground and attached to the surface of
`said handset.
`27. A method as claimed in claim 19, further compris(cid:173)
`ing the steps of producing a key signal when a talk start
`key is pressed; and responsive to said key signal, making
`said telephone respond to said call.
`28. A method as claimed in claim 22, further compris(cid:173)
`ing the step of, responsive to the stoppage of transmis(cid:173)
`sion of said signaling tone, connecting said mobile tele(cid:173)
`phone to a telephone from which said call has been
`made.
`• • • • •
`
`7
`14. An apparatus as claimed in claim 13, wherein said
`touch sensor means comprises a conductive mesh.
`15. An apparatus as claimed in claim 13, wherein said
`annunciating means comprises a speaker installed in said
`handset.
`16. An apparatus as claimed in claim 13, wherein said
`communicating means further comprises transmitter
`means for transmitting the output of said microphone
`over a radio frequency; and receiver means for receiv(cid:173)
`ing a radio frequency signal and demodulating the re- 10
`ceived signal to provide a demodulated signal to said
`receiver.
`17. An apparatus as claimed in claim 16, wherein said
`apparatus is installed in a vehicle.
`18. An apparatus as claimed in claim 17, wherein said 15
`vehicle has a steering wheel, said touch sensor means
`being attached to said steering wheel.
`19. A method of making a telephone respond to a call
`addressed thereto, comprising the following steps of:
`annunciating a reception of said call;
`producing a touch detection signal when a touch
`sensors touched; and
`responsive to said touch detection signal, making said
`telephone respond to said call only after the annun-
`ciation of said call.
`20. A method as claimed in claim 19, further compris(cid:173)
`ing the step of, responsive to said reception of said call,
`transmitting a signaling tone, wherein said step of mak(cid:173)
`ing said telephone respond to said call comprises the
`step of stopping the transmission of said signaling tone. 30
`21. A method of making a mobile telephone respond
`to a call meant therefor, comprising the following steps
`of:
`detecting a call signal to produce a first detection
`signal;
`responsive to said first detection signal, transmitting a
`call response signal;
`receiving a channel designation signal which is trans(cid:173)
`mitted from a base station in response to said call
`response signal and which designates a speech 40
`channel to said mobile telephone;
`responsive to said channel designation signal, tuning
`said mobile telephone to said speech channel;
`receiving an alert signal;
`responsive to the received alert signal, generating a 45
`ringing tone;
`responsive to said received alert signal, transmitting a
`signaling tone;
`
`35
`
`50
`
`55
`
`60
`
`65
`
`

`

`:
`
`UNITED STATES PATENT AND TRADEMARK OFFICE
`CERTIFICATE OF CORRECTION
`5,329,577
`July 12, 1994
`Hidehiko Norimatsu
`It is certified that error appears in the above-identified patent and that said Letters Patent is hereby
`corrected as shown below:
`
`PATENT NO.
`DATED
`INVENTDR(S) :
`
`Column 4, line 20, delete "53l." and insert --531--.
`
`Signed and Sealed this
`
`Eighteenth Day of October, 1994
`
`Attest:
`
`Attesting Officer
`
`Commissioner of Patents and Tradef!!arks
`
`BRUCE LEHMAN
`
`