Abstract: A viscoelastic body is interposed between a vibrating membrane vibrating in association with a piezoelectric vibrator composed of a piezoelectric element and a base and a support member supporting the vibrating membrane. The viscoelastic body attenuates vibration transmitted from the support member to the vibrating membrane and converts vibration of the vibrating membrane in the surface direction parallel to its main surfaces to vibration of the vibrating membrane in the direction nearly perpendicular to the surface direction. The vibrating membrane is annular with an opening at the center, and the base is joined to the vibrating membrane coaxially with opening.

Abstract: One object of the present invention is to an achieve increase of amplitude of vibrations and/or flattening of frequency dependence of the amplitude of a piezoelectric actuator. Piezoelectric actuator (100) has first piezoelectric vibrator (102), second piezoelectric vibrator (104), and vibrating membrane (106). First piezoelectric vibrator (102) includes first pedestal (116) and first piezoelectric element (112) connected to the first pedestal. Second piezoelectric vibrator (104) includes second pedestal (118) and second piezoelectric element (114) connected to the second pedestal. Vibrating membrane (106) has opening (108). First piezoelectric vibrator (102) is connected to one surface of vibrating membrane (106) straddling opening (108) of the vibrating membrane. Second piezoelectric vibrator (102) is connected to another surface of vibrating membrane (106) straddling opening (108) of the vibrating membrane.

Abstract: A piezoelectric acoustic device comprises: at least two piezoelectric actuators; a support body that supports the at least two piezoelectric actuators; and a signal input unit that drives the at least two piezoelectric actuators at respective arbitrary times. At least one pair of piezoelectric actuators among the at least two piezoelectric actuators is arranged in such a manner that their sound radiation surfaces face each other with a predetermined gap.

Abstract: A viscoelastic body is interposed between a vibrating membrane vibrating in association with a piezoelectric vibrator composed of a piezoelectric element and a base and a support member supporting the vibrating membrane. The viscoelastic body attenuates vibration transmitted from the support member to the vibrating membrane and converts vibration of the vibrating membrane in the surface direction parallel to its main surfaces to vibration of the vibrating membrane in the direction nearly perpendicular to the surface direction. The vibrating membrane is annular with an opening at the center, and the base is joined to the vibrating membrane coaxially with opening.

Abstract: Piezo-electric actuator 50 of the present invention comprises piezo-electric element 10 for performing expansion/contraction motions in accordance with an electric field condition, seat 20 to which piezo-electric element 10 is adhered on at least one surface thereof, and supporting member 45 for supporting piezo-electric element 10 and seat 20, wherein piezo-electric element 10 and seat 20 vibrate up and down in accordance with the expansion/contraction motions of piezo-electric element 10. Seat 20 is connected to supporting member 45 through vibration 30 film which is less rigid than this seat 20.

Abstract: One object of the present invention is to an achieve increase of amplitude of vibrations and/or flattening of frequency dependence of the amplitude of a piezoelectric actuator. Piezoelectric actuator (100) has first piezoelectric vibrator (102), second piezoelectric vibrator (104), and vibrating membrane (106). First piezoelectric vibrator (102) includes first pedestal (116) and first piezoelectric element (112) connected to the first pedestal. Second piezoelectric vibrator (104) includes second pedestal (118) and second piezoelectric element (114) connected to the second pedestal. Vibrating membrane (106) has opening (108). First piezoelectric vibrator (102) is connected to one surface of vibrating membrane (106) straddling opening (108) of the vibrating membrane. Second piezoelectric vibrator (102) is connected to another surface of vibrating membrane (106) straddling opening (108) of the vibrating membrane.

Abstract: Piezoelectric actuator (51) includes a piezoelectric element (11) that performs expansion/contraction movement in accordance with the state of an electrical field, a base (21) with the piezoelectric element (11) adhered to one surface thereof, and a support member (46) for supporting the piezoelectric element (11) and the base (21), the piezoelectric element (11) and base (21) vibrating up and down in accordance with the expansion/contraction movement of the piezoelectric element (11). The base (21) is connected to the support member (46) by way of a vibration film (31) having less rigidity than the base (21). In addition, the piezoelectric element (11) and support member (46) have different outline shapes.

Abstract: Provided is a piezoelectric speaker (40) including: a piezoelectric element (42) that deforms in response to an input signal; a diaphragm (43) that is set in bending motion by the piezoelectric element (42) to generate sound; and a resilient portion (44) that holds at least a part of an outer edge of the diaphragm (43). The piezoelectric speaker further includes a lock portion (46) arranged to block extension of the diaphragm (43) by coming into contact with a part of a vibration plane of the diaphragm (43) when an input signal is not input to obtain a lock state and to release the lock state immediately after the input signal is input. Consequently, bending motion of the diaphragm (43) can be started quickly and movement of the diaphragm is not obstructed after starting of the bending motion.

Abstract: Arrangement of an internal component (not shown) arranged in the vicinity of the top side is different from that of the hinge side of an image element protective screen (2). An actuator (5) is fixed to the top side of the image element protective screen (2) and an actuator (4) is fixed to the hinge side of the image element protective screen (2). Since Arrangement of the internal component in the vicinity of the actuator is different, different sound pressure frequency characteristics or the like are experienced when each actuator is driven independently. When the actuators (4, 5) are driven simultaneously, sound pressure frequency characteristics and vibration frequency characteristics can be flattened. Isolation between the vibration speed of a vibrator near one actuator and the vibration speed of a vibrator in the region near the other actuator that are produced by respective actuators is set at 10 dB or above.

Abstract: An object is to provide an audio circuit in which flow of excessive current through a capacitive speaker and a drive circuit thereof can be prevented while degradation of sound quality of high-pitched tones is suppressed. The audio circuit for driving a capacitive speaker includes: a weighting circuit for performing weighting in conformity with frequency components of an audio signal; and a signal-voltage limiting compression circuit for compressing a signal, which is input to the drive amplifier or which has been output from the drive circuit, at a prescribed compression ratio in accordance with a difference voltage between the output signal of the weighting circuit and a preset threshold voltage when the weighted signal exceeds the threshold voltage.

Abstract: A piezoelectric acoustic device comprises: at least two piezoelectric actuators; a support body that supports the at least two piezoelectric actuators; and a signal input unit that drives the at least two piezoelectric actuators at respective arbitrary times. At least one pair of piezoelectric actuators among the at least two piezoelectric actuators is arranged in such a manner that their sound radiation surfaces face each other with a predetermined gap.

Abstract: An object is to provide an audio circuit in which flow of excessive current through a capacitive speaker and a drive circuit thereof can be prevented while degradation of sound quality of high-pitched tones is suppressed. The audio circuit for driving a capacitive speaker includes: a weighting circuit for performing weighting in conformity with frequency components of an audio signal; and a signal-voltage limiting compression circuit for compressing a signal, which is input to the drive amplifier or which has been output from the drive circuit, at a prescribed compression ratio in accordance with a difference voltage between the output signal of the weighting circuit and a preset threshold voltage when the weighted signal exceeds the threshold voltage.

Abstract: Piezo-electric actuator 50 of the present invention comprises piezo-electric element 10 for performing expansion/contraction motions in accordance with an electric field condition, seat 20 to which piezo-electric element 10 is adhered on at least one surface thereof, and supporting member 45 for supporting piezo-electric element 10 and seat 20, wherein piezo-electric element 10 and seat 20 vibrate up and down in accordance with the expansion/contraction motions of piezo-electric element 10. Seat 20 is connected to supporting member 45 through vibration 30 film which is less rigid than this seat 20.

Abstract: An acoustic processing system for an electronic device includes: an equalizer processor which boosts or cuts a digital signal which has been subjected to an acoustic process for each of frequency components; a low-pass filter which extracts a low-range signal from the signal from the equalizer processor and outputs the signal; a high-pass filter which extracts a high-range signal from the signal from the equalizer processor and outputs the signal; a high-frequency compressor which compresses the high-range signal; an adder which generates an addition of the low-range signal and the compressed high-range signal; and a speaker which outputs a sound in accordance with the addition of the signal.

Abstract: Provided is a piezoelectric speaker (40) including: a piezoelectric element (42) that deforms in response to an input signal; a diaphragm (43) that is set in bending motion by the piezoelectric element (42) to generate sound; and a resilient portion (44) that holds at least a part of an outer edge of the diaphragm (43). The piezoelectric speaker further includes a lock portion (46) arranged to block extension of the diaphragm (43) by coming into contact with a part of a vibration plane of the diaphragm (43) when an input signal is not input to obtain a lock state and to release the lock state immediately after the input signal is input. Consequently, bending motion of the diaphragm (43) can be started quickly and movement of the diaphragm is not obstructed after starting of the bending motion.

Abstract: Piezoelectric actuator (51) includes a piezoelectric element (11) that performs expansion/contraction movement in accordance with the state of an electrical field, a base (21) with the piezoelectric element (11) adhered to one surface thereof, and a support member (46) for supporting the piezoelectric element (11) and the base (21), the piezoelectric element (11) and base (21) vibrating up and down in accordance with the expansion/contraction movement of the piezoelectric element (11). The base (21) is connected to the support member (46) by way of a vibration film (31) having less rigidity than the base (21). In addition, the piezoelectric element (11) and support member (46) have different outline shapes.

Abstract: Arrangement of an internal component (not shown) arranged in the vicinity of the top side is different from that of the hinge side of an image element protective screen (2). An actuator (5) is fixed to the top side of the image element protective screen (2) and an actuator (4) is fixed to the hinge side of the image element protective screen (2). Since Arrangement of the internal component in the vicinity of the actuator is different, different sound pressure frequency characteristics or the like are experienced when each actuator is driven independently. When the actuators (4, 5) are driven simultaneously, sound pressure frequency characteristics and vibration frequency characteristics can be flattened. Isolation between the vibration speed of a vibrator near one actuator and the vibration speed of a vibrator in the region near the other actuator that are produced by respective actuators is set at 10 dB or above.

Abstract: A driving unit for an electronic device including a planar voice coil, a resilient member, a support section moveably attached to a plate member of the electronic device by the resilient member, and a first magnet disposed inside the planar voice coil and a second magnet disposed outside the planar voice coil, wherein the first and second magnets are fixedly attached to the support section, wherein the plate member comprises a transparent central section and another section adjacent to the transparent central section, the plate member being moveably attached to the another section by the resilient member.

Abstract: An electronic device, in which accommodation space for a display can be extended over the space where a speaker might be provided. A portable terminal, as an example of an electronic device, is provided with a display/speaker section, an operating section, and a microphone on the front surface of its main body. The portable terminal does not have an independent speaker. A display cover located in front of the display/speaker section for protecting the display surface vibrates in response to an audio signal by a drive to output sound. Consequently, the display can be situated even over the space where a speaker might be provided.

Abstract: When an incoming call is received, a control unit confirms using an open/close sensor whether or not a mobile terminal device is in the close state. When the mobile terminal device is folded, the control unit establishes a communications state, changes the amplification rate of a first amplifier such that the reception signal can be output at the sound level predetermined as the level to be output from the receiver, changes the signal path so that the received voice can be output from the speaker by operating a switch, and changes the transmitted voice sensitivity by adjusting the amplification rate of a second amplifier so that the microphone can collect sound although it is separate from the mouse of the user, thereby realizing the conversation with the mobile terminal device folded.