Patent Publication Number: US-2010119101-A1

Title: Integrated Audiovisual Output Device

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to an output device, and more particularly relates to an integrated audiovisual output device. 
     BACKGROUND OF THE INVENTION 
     Electronic devices with audiovisual capabilities have grown increasingly smaller and commonplace. Accordingly, miniaturization of audiovisual components has also grown important. However, traditional designs have required separate components for presenting video (e.g., a liquid crystal display (LCD) including two panels, typically composed of glass, with a liquid crystal layer therebetween) and audio (e.g., a speaker cone attached to a voice coil). 
     Recent developments in technology have led to attempts to integrate these audio and video components. For example, U.S. Pat. No. 6,427,017 teaches arranging a transparent piezoelectric speaker panel over an LCD display. Such an arrangement has the disadvantage of an increased thickness of the front panel, which results in both an increase in the device size as well as a decrease in the brightness and clarity of the display. Furthermore, piezoelectric elements have a relatively narrow frequency response compared to other audio output devices (e.g., electromagnetic speakers). 
     U.S. Patent Application Publication No. 2006/0227981 teaches attaching a piezoelectric excitation source to an end of one of the LCD substrate, thereby permitting the substrate to be used as a vibration plate in conjunction with an externally supplied sound signal. Although an improvement over the prior art, this requires both the use of a piezoelectric excitation source and an externally supplied sound signal, which results in both increased device size (due to the external excitation source and external generation of the sound signal) and diminished frequency response (due to the use of piezoelectric rather than electromagnetic technology). Moreover, many amplifier circuits have difficulty driving piezoelectric devices, which are primarily capacitive loads. 
     Accordingly, there exists a need for an integrated audiovisual output device which does not suffer from one or more of the above-noted problems exhibited by conventional devices. 
     SUMMARY OF THE INVENTION 
     The present invention meets the above-noted need by providing, in an illustrative embodiment thereof, an integrated audiovisual output device with a voice coil and/or a magnet contiguous with a display panel. 
     In accordance with one aspect of the invention, an integrated audiovisual output device includes at least one display comprising at least one panel, at least one voice coil contiguous with the at least one panel, and at least one magnet proximate to the at least one voice coil, wherein at least one panel is vibrated in order to generate audio output. The device may also include at least one frame arranged to house at least the at least one panel and the at least one voice coil. The at least one voice coil may, for example, be housed within the at least one frame or embedded within the at least one frame. The at least one magnet may, for example, be housed within the frame, embedded within the frame, or external to the frame. 
     In accordance with another aspect of the invention, an integrated audiovisual output device includes at least one display comprising at least one panel, at least one magnet contiguous with the at least one panel, and at least one voice coil proximate to the at least one magnet, wherein at least one panel is vibrated in order to generate audio output. The device may also include at least one frame arranged to house at least the at least one panel and the at least one magnet. The at least one magnet may, for example, be housed within the at least one frame or embedded within the at least one frame. The at least one voice coil may, for example, be housed within the frame, embedded within the frame, or external to the frame. 
     In accordance with another aspect of the invention, an integrated audiovisual output device includes at least one display comprising at least one panel and an audio transducer for vibrating at least one panel of the at least one display, wherein at least one panel comprises driver circuitry operative to produce at least audio data for presentation by the audio transducer. The at least one panel comprising driver circuitry may itself be vibrated or the display may include at least a first panel comprising driver circuitry and a second panel which is vibrated. The audio transducer may include, for example, a piezoelectric element and/or a voice coil. 
     These and other features and advantages of the present invention will become apparent from the following detailed description of illustrative embodiments thereof, which is to be read in connection with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cross-sectional view showing at least a portion of an exemplary integrated audiovisual device having a voice coil contiguous with a display panel and a magnet external to a frame of the device, in accordance with an embodiment of the invention. 
         FIG. 2  is a cross-sectional view showing at least a portion of an exemplary integrated audiovisual device having a voice coil contiguous with a display panel and a magnet embedded within a frame of the device, in accordance with an embodiment of the invention. 
         FIG. 3  is a cross-sectional view showing at least a portion of an exemplary integrated audiovisual device having a voice coil contiguous with a display panel and a magnet housed within a frame of the device, in accordance with an embodiment of the invention. 
         FIG. 4  is a cross-sectional view showing at least a portion of an exemplary integrated audiovisual device having a magnet contiguous with a display panel and a voice coil external to a frame of the device, in accordance with an embodiment of the invention. 
         FIG. 5  is a cross-sectional view showing at least a portion of an exemplary integrated audiovisual device having a magnet contiguous with a display panel and a voice coil embedded within a frame of the device, in accordance with an embodiment of the invention. 
         FIG. 6  is a cross-sectional view showing at least a portion of an exemplary integrated audiovisual device having a magnet contiguous with a display panel and a voice coil housed within a frame of the device, in accordance with an embodiment of the invention. 
         FIG. 7  is a cross-sectional view showing at least a portion of an exemplary integrated audiovisual device wherein a display panel contains driver circuitry and is vibrated to produce audio output. 
         FIG. 8  is a cross-sectional view showing at least a portion of an exemplary integrated audiovisual device wherein a first display panel contains driver circuitry and a second display panel is vibrated to produce audio output. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     At least one aspect of the present invention will be described herein in the context of illustrative devices including a single liquid crystal display, a single spiral induction voice coil, a single permanent magnet, and a single frame. While reference may be made herein to certain device components, it is to be understood that the present invention is not limited to these or any particular device components or arrangements thereof. Rather, the invention is more generally applicable to techniques for integrated audiovisual output. For example, this device may be used with any number and type of displays, including, but not limited to, liquid crystal displays, plasma screens, touch-sensitive screens, electronic paper displays, light-emitting diodes, thin-film transistor (TFT) displays, etc. Each display may include any number and type of panels, which may include, for example, glass, plastic, amorphous silicon, polysilicon, continuous-grain silicon, etc., or any substantially transparent material. Likewise, this device may be used with any number and type of voice coils (including, but not limited to, spiral induction coils), and magnets (including, but not limited to, permanent magnets and electromagnets). Furthermore, the device may be constructed with any number of frames or with no frame. Techniques of the present invention provide an integrated audiovisual output device having decreased size and enhanced frequency response compared to standard audiovisual presentation arrangements. Unlike conventional approaches, the present invention permits the integration of a voice coil and/or driver circuitry with the display. 
       FIG. 1  is a cross-sectional view showing at least a portion of an exemplary integrated audiovisual device  100 , formed in accordance with an embodiment of the invention. Audiovisual device  100  includes a display  110 , which may be a liquid crystal display comprising two panels  111 ,  113  with a liquid crystal layer  112  therebetween. Display  110  may be affixed to a frame  130 , which is preferably composed of a substantially rigid material, such as plastic and/or metal, although the invention is not limited to a rigid frame. Frame  130  is preferably substantially fixed relative to display  110 , which is preferably at least partially free to move in relation to the fixed frame so as to produce vibrations. There may be an interior space  120  defined by display  110  and an interior of frame  130  (e.g., a bottom and sidewalls of the frame). This space may be at least partially occupied by, for example, backlighting circuitry  160  for use in illuminating the display  110  and/or driver circuitry  170  for use in generating audio and/or video output for presentation on audiovisual device  100 . Space  120  may also serve as a resonating cavity for the audio output. 
     Audiovisual device  100  further comprises an audio transducer including a voice coil  140  contiguous with a panel  113  of display  110  and a magnet  150  external to frame  130 . The voice coil  140  and magnet  150 , when used in conjunction with one another, may be used for presenting audio output. The voice coil  140  is preferably capable of producing vibrations in at least panel  113 . Voice coil  140  may be attached to panel  113  using any known attachment means, such as, for example, fasteners (e.g., screws, etc.), adhesive, etc, as will become apparent to those skilled in the art. Alternatively, voice coil  140  may, for example, be printed onto panel  113  (e.g., using electrically conductive ink, etc.). Voice coil  140  may, for example, include a spiral inductor, wire segments, or alternative means for generating an electromagnetic field when a current is passed through the voice coil. Voice coil  140  may be controlled by driver circuitry  170  which may, for example, be located on a panel  113  of display  110  (e.g., system-on-glass), in space  120 , or outside frame  130 . Magnet  150 , which may include, for example, a permanent magnet and/or an electromagnet, may be located external to frame  130 , as shown, but still proximate enough to exert a magnetic influence on voice coil  140 . 
     When an electric current corresponding to a signal generated by driver circuitry associated with the audio transducer is passed through voice coil  140 , which is within the magnetic field of magnet  150 , the voice coil will attempt to move in relation to the magnet (e.g., either towards or away from the magnet, depending on a direction of the current passing through the voice coil), thus inducing vibrations in at least the contiguous panel  113 . 
       FIGS. 2 and 3  are cross-sectional views depicting alternative exemplary configurations of the integrated audiovisual device  100  shown in  FIG. 1 , in accordance with other embodiments of the invention. For example,  FIG. 2  depicts an audiovisual device  200  including an audio transducer comprising voice coil  240  contiguous with a panel  113  of display  110 , as in the audiovisual device  100  (see  FIG. 1 ), and a magnet  250  embedded in a bottom of frame  130 . It is to be understood that magnet  250  is not limited to being embedded in frame  130  in the particular location shown. Rather, magnet  250  may be embedded essentially anywhere in frame  130  that is proximate enough to voice coil  240  so as to cause the voice coil to move relative to the magnet and thereby induce vibrations at least in panel  113 . For example, magnet  250  may be embedded in one or more sidewalls of frame  230 . As an alternative, the frame  130  itself may comprise a magnetic material and thereby act as a magnet. 
     Likewise,  FIG. 3  depicts an audiovisual device  300  including an audio transducer comprising voice coil  340  contiguous with panel  113  of display  110 , as in the audiovisual device  100  (see  FIG. 1 ), and a magnet  350  located housed within frame  130 . Magnet  350  may, for example, be attached to frame  130  using any known attachment means, such as, but not limited to, fasteners (e.g., screws, etc.), adhesive, etc, as will become apparent to those skilled in the art. The location of magnet  350  within frame  130  is not limited to the particular location shown, but may be located essentially anywhere in frame  130  that is proximate enough to voice coil  340  so as to cause the voice coil to move relative to the magnet and thereby induce vibrations at least in panel  113 . For example, magnet  350  may be attached to an interior surface of one or more sidewalls of frame  130 . Alternatively, magnet  350  may, for example, be printed onto frame  130  (e.g., using magnetic ink, etc.). 
       FIG. 4  is a cross-sectional view showing at least a portion of an exemplary integrated audiovisual device  400 , formed in accordance with another embodiment of the invention. Audiovisual device  400  includes a display  410 , which may be a liquid crystal display comprising two panels  411 ,  413  with a liquid crystal layer  412  therebetween. Display  410  may be affixed to a frame  430 , which is preferably composed of a substantially rigid material, such as plastic and/or metal, although the invention is not limited to a rigid frame. Frame  430  is preferably substantially fixed relative to display  410 , which is preferably at least partially free to move in relation to the fixed frame so as to produce vibrations. There may be an interior space  420  defined by display  410  and an interior of frame  430  (e.g., a bottom and sidewalls of the frame). This space may be at least partially occupied by, for example, backlighting circuitry  460  for use in illuminating the display  410  and/or driver circuitry  470  for use in generating audio and/or video output for presentation on audiovisual device  400 . Space  420  may also serve as a resonating cavity for the audio output. 
     Audiovisual device  400  further comprises an audio transducer including a magnet  440  contiguous with a panel  413  of display  410  and a voice coil  450  external to frame  430 . The magnet  440  and voice coil  450 , when used in conjunction with one another, may be used for presenting audio output. The magnet  440  is preferably capable of producing vibrations in at least panel  413 . Magnet  440  may be attached to panel  413  using any known attachment means, such as, for example, fasteners (e.g., screws, etc.), adhesive, etc, as will become apparent to those skilled in the art. Alternatively, magnet  440  may, for example, be printed onto panel  413  (e.g., using magnetic ink, etc.). Magnet  440 , which may include, for example, a permanent magnet and/or an electromagnet, should be located with sufficient proximity to voice coil  440  so that the magnet will be caused to move relative to voice coil  450  by a current flowing through the voice coil. Voice coil  450  may, for example, include a spiral inductor, wire segments, or alternative means for generating an electromagnetic field when a current is passed through the voice coil. Voice coil  450  may be controlled by driver circuitry (not shown) which may, for example, be located on a panel  413  of display  410  (e.g., system-on-glass), in space  420 , or outside frame  430 . 
     As in the illustrative embodiments described above, when an electric current (e.g., corresponding to a signal generated by driver circuitry) is passed through voice coil  450 , which is within the magnetic field of magnet  440 , the voice coil will attempt to move in relation to the magnet. However, in the exemplary audiovisual device  400 , since the voice coil  450  is affixed to frame  430  and thus essentially prevented from exhibiting any significant movement, magnet  440  will attempt to move contiguous panel  413  (which is preferably free to move along frame  430 ) relative to the magnet, thus inducing vibrations in at least the panel. The direction of movement relative to voice coil  450  (e.g., towards or away from the voice coil) will depend upon the direction of the current passing through the voice coil. 
       FIGS. 5 and 6  are cross-sectional views depicting alternative exemplary configurations of the integrated audiovisual device  400  shown in  FIG. 4 , in accordance with other embodiments of the invention. For example,  FIG. 5  depicts an audiovisual device  500  including an audio transducer comprising magnet  440  contiguous with a panel  413  of display  410 , as in the audiovisual device  400  (see  FIG. 4 ), and a voice coil  550  embedded in a bottom of frame  430 . It is to be understood that voice coil  550  is not limited to being embedded in frame  430  in the particular location shown. Rather, voice coil  550  may be embedded essentially anywhere in frame  430  that is proximate enough to magnet  440  so that a current passing through the voice coil is able to cause a movement of the magnet and induce vibrations at least in contiguous panel  413 . For example, voice coil  550  may be embedded in one or more sidewalls of frame  430 . 
     Likewise,  FIG. 6  depicts an audiovisual device  600  including an audio transducer comprising magnet  440  contiguous with panel  413  of display  410 , as in the audiovisual device  400  (see  FIG. 4 ), and a voice coil  650  located housed within frame  430 . Voice coil  650  may, for example, be attached to frame  430  using any known attachment means, such as, but not limited to, fasteners (e.g., screws, etc.), adhesive, etc, as will become apparent to those skilled in the art. The location of voice coil  650  within frame  430  is not limited to the particular location shown, but may be located essentially anywhere in frame  430  so that a current passing through the voice coil is able to cause a movement of the magnet and induce vibrations at least in panel  413 . For example, voice coil  650  may be attached to an interior surface of one or more sidewalls of frame  430 . Alternatively, voice coil  650  may, for example, be printed onto frame  430  (e.g., using electrically conductive ink, etc.). 
       FIG. 7  is a cross-sectional view showing at least a portion of an exemplary integrated audiovisual device  700 , formed in accordance with an embodiment of the invention. Audiovisual device  700  includes a display  710 , which may be a liquid crystal display comprising two panels  711 ,  713  with a liquid crystal layer  712  therebetween. Display  710  may be mounted on a frame  730 , which is preferably composed of a rigid material, such as plastic and/or metal. There may be an interior space  720  defined by display  710  and a bottom and sidewalls of frame  730 , which may be at least partially occupied by, for example, backlighting circuitry for use in illuminating display  710 . At least one panel  713  of display  710  is capable of being vibrated (e.g., by an audio transducer  750 , which may include, for example, a piezoelectric element, a voice coil, a magnet, etc.) to produce audio output controlled at least in part by driver circuitry  740  located on the same panel (e.g., using system-on-glass methodologies). It is to be appreciated that the driver circuitry  740  and audio transducer  750  need not be located on the same panel (e.g.,  713 ) of display  710 . 
     For example,  FIG. 8  is a cross-sectional view showing at least a portion of an exemplary integrated audiovisual device  800 , formed in accordance with an embodiment of the invention. Audiovisual device  800 , like device  700  depicted in  FIG. 7 , includes a display  810  which may be a liquid crystal display comprising first and second panels  811  and  813 , respectively, with a liquid crystal layer  812  therebetween. Display  810  may be mounted to a frame  830 , which is preferably composed of a substantially rigid material, such as plastic and/or metal. There may be an interior space  820  defined by display  810  and a bottom and sidewalls of frame  830 , which may be at least partially occupied by, for example, backlighting circuitry for use in illuminating display  810 . At least first panel  813  is preferably capable of being vibrated (e.g. by an audio transducer  850 , which may include, for example, a piezoelectric element, voice coil, magnet, etc.) to produce audio output controlled at least in part by driver circuitry  840  located on at least second panel  811  (e.g., using system-on-glass methodologies). 
     Although illustrative embodiments of the present invention have been described herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various other changes and modifications may be made therein by one skilled in the art without departing from the scope of the appended claims.