Abstract:
A television provides a full range of content to be rendered to the user, while complying with strict hospital electrical isolation standards. An interface unit receives control inputs from a pillow speaker, translates the control inputs to appropriate commands, and outputs the commands to a television via a commercial grade control interface, and to a set top box. The interface unit receives an audio output signal from the television, galvanically isolates the audio signal, selectively amplifies the audio signal in response to control inputs from the pillow speaker, and outputs the volume-controlled, isolated audio signal to the pillow speaker. In this manner, the television can display any programming carried on a cable (a direct input to the television), as well as any audio-video content provided to the television from the set top box, which may include pay-per-view, instructional videos, interactive gaming, web browsing, and the like.

Description:
[0001]     This application is a continuation-in-part of U.S. application Ser. No. 10/694,969, filed 28 Oct. 2003, the entirety of which is incorporated herein by reference. 
     
    
     BACKGROUND  
       [0002]     The present invention relates generally to the field of electronics and in particular to a system and method for selecting and controlling the content displayed on a television.  
         [0003]     The modern television does far more than its original function of displaying broadcast television shows. While the television still performs that function, it additionally displays a wide variety of other content, including prerecorded audio/video content. The television provides a user interface for interactive services, such as accessing the World Wide Web. The provision of the varied content displayed on a television is often controlled and coordinated by an external unit having a variety of content source inputs, ubiquitously referred to as a “set top box.” 
         [0004]     The ability of a television to display a variety of types of content has been exploited by the lodging and hospital industries. For example, a television in a hotel room, in addition to providing traditional broadcast and prerecorded audio/video content, may additionally offer interactive content, allowing a guest to view and order from a room service menu, or approve his or her bill for expedited checkout. This functionality is enabled by television manufacturers adding a sophisticated, “smart” interface and control module—referred to herein as a “commercial grade control interface”—to consumer grade televisions, which are then marketed as commercial grade (also known in the art as hospitality grade).  
         [0005]     Hospitals additionally exploit the ability of a television to provide a variety of content. A television in a hospital room, in addition to displaying broadcast and prerecorded audio/video content, may additionally provide educational material, such as reviewing common medical procedures and providing care instructions. A hospital may also provide Internet access via a television and appropriate input devices, such as a wired or wireless keyboard with a mouse. Typically, basic functionality of the television—such as content selection, channel selection, volume control, and the like—is controlled by an existing, wired remote control device commonly known as a “pillow speaker.” 
         [0006]     As its name implies, a pillow speaker is located physically on or near the patient&#39;s bed, and includes a speaker. Originally a nurse call and intercom device, the pillow speaker has evolved to include a variety of control inputs. In particular, a pillow speaker typically includes at least a numeric key pad, directional keys, and volume control keys, as well as a nurse call button. Hospitals impose stringent electrical conditions on any device that may contact a patient or sensitive electronics positioned around the patient&#39;s bed. In particular, they require strict galvanic isolation of any such device, to eliminate the possibility of stray current through ground loops.  
         [0007]     Television manufacturers have addressed this need by a providing galvanic isolation circuit at the audio output, known as a pendent control jack, in addition to the commercial grade control interface, in television sets marketed as health care grade (also known in the art as hospital grade). While this allows a user to control the television from the pillow speaker while complying with hospital electrical regulations, it does not address how to control a set top box, which may provide, e.g., Web browsing functionality, educational programming, on-line access to patient records, video-on-demand, interactive video games, and similar video and audio-video content to the television.  
       SUMMARY  
       [0008]     A television system is disclosed herein that provides a full range of content to be rendered to the user, while complying with strict hospital electrical isolation standards. In one or more embodiments, an interface unit receives control inputs from a pillow speaker, translates the control inputs to appropriate commands, and outputs the commands to a television via a commercial grade control interface, and to a set top box. The interface unit receives an audio output signal from the television, galvanically isolates the audio signal, selectively amplifies the audio signal in response to control inputs from the pillow speaker, and outputs the volume-controlled, isolated audio signal to the pillow speaker. In this manner, the television can display any programming carried on a cable (a direct input to the television), as well as any audio-video content provided to the television from the set top box, with isolated audio provided to the pillow speaker.  
         [0009]     In one embodiment, the present invention relates to a television system. The television system includes a television having a commercial grade control interface and having a cable input, a video input, an audio input, and an audio output. The television system also includes a set top box receiving audio-video content from a remote server, and providing a video signal to the television video input and an audio signal to the television audio input, the set top box including a data transfer interface. The television system further includes a cable providing a modulated signal to the television cable input, the signal carrying one or more channels of audio-video content. The television system additionally includes a remote control device including a speaker. Finally, the television system includes an interface unit connected to the set top box via the data transfer interface, connected to the television via the commercial grade control interface, receiving audio from the television via the audio output, and receiving commands from and outputting audio to the remote control device. The interface unit is operative to command the television to display video content from either the set top box or the cable in response to commands from the remote control device, and is further operative to output audio to the remote control device speaker.  
         [0010]     In another embodiment, the present invention relates to a method of controlling, by an interface unit, the content displayed on a television. Control inputs are received from a user. The television is configured, via a commercial grade control interface, to display content from either a cable or a set top box, in response to the control inputs. The set top box is configured to conditionally output content to the television, in response to the control inputs. The set top box is periodically monitored for proper operation.  
         [0011]     In yet another embodiment, the present invention relates to an interface unit for a television system. The interface unit includes an audio input; a pillow speaker interface receiving control inputs from a user and outputting a galvanically isolated audio signal; a television interface outputting commands to a commercial grade control interface; a set top box interface outputting commands to a set top box and receiving status information from the set top box; and a processor operative to generate commercial grade control interface commands and set top box commands in response to control inputs received at the pillow speaker interface. 
     
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0012]      FIG. 1  is a functional block diagram of a television control system according to one embodiment of the present invention.  
         [0013]      FIG. 2  is a flow diagram depicting a method of controlling the content displayed on a television.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0014]      FIG. 1  depicts a television control system, indicated generally by the numeral  10 , according to one embodiment of the present invention. The television control system  10 , particularly suited for use in a hospital, comprises a consumer or health care grade television  12 , set top box  14 , interface unit  16 , and a remote-control device having a speaker, such as the pillow speaker  18 .  
         [0015]     The television  12  includes a tuner  20  and display  22  as conventionally known, and a commercial grade control interface  24 . The commercial grade control interface  24  is known in the art by various brand names, such as SmartPort™, MPI™, CCI™, and DCP™. The television  12  additionally includes various control and processing circuits as well known in the art, which are not depicted in  FIG. 1  for clarity. In particular, the television  12  includes audio processing circuits that process and amplified audio signals from the tuner  20  or an external audio input port, and output a processed audio signal at an audio output port  28 . In one embodiment, the audio output port  28  comprises a pendent control jack that outputs a galvanically isolated audio signal, a data signal, and a ground reference.  
         [0016]     The television  12  receives a modulated signal comprising one or more audio-video channels from a conventional television programming distribution cable, output by a remotely-located cable head end  29 , at cable input  30 . The modulated cable signal is demodulated, and an audio-video channel extracted, by the tuner  20 , under control of the commercial grade control interface  24 . The tuner  20  provides a video signal to the display  22 , and audio to the audio output port  28 . The display  22 , which may comprise a cathode ray tube (CRT), LCD display, plasma display, or the like, renders the video to be viewed by the patient.  
         [0017]     The television  12  additionally receives a direct video signal, such as an SVGA signal, from the set top box  14  at a video input port  32 . The display  22  may directly render the video signal. The set top box  14  additionally provides an audio signal at the audio input port  26 . The set top box  14 , which may for example comprise the Activity  300  unit available from Fujitsu/Siemens, and/or BCM Model STB1100, receives the video and audio-video content over a high-bandwidth local area network (LAN) from a remotely-located server  34 , the output of which is distributed to a plurality of hospital rooms by a router  36 .  
         [0018]     The server  34  retrieves audio/video and interactive content from a variety of sources, including a video server  38  and computer network such as the Internet  40 . The video server  34  may store and provide premium audio/video content, such as movies, recorded concerts, and the like. The video server  34  may additionally store and provide customized audio/video content, such as medical documentaries, educational programs, hospital introduction and orientation programs, emergency evacuation instructions, and the like. The server  34  may also retrieve a broad variety of audio/video and interactive content from the Internet  40 , such as the World Wide Web.  
         [0019]     The set top box  14  may additionally generate audio-video displays internally, such as introductory screens, menus, icons, and the like, as part of a television content selection and control software, such as the TigerNet™ software from Telerent Leasing Corporation of Raleigh, N.C.  
         [0020]     The television control system  10  also includes the interface unit  16 . The interface unit  16  includes a processor or microcontroller (not shown) and software operative to translate between various command and control formats. For example, the interface unit  16  receives inputs from the pillow speaker  18  and/or one or more other input devices  46 ,  48 ,  52 ,  54 . These may be in the form of RC-5 codes for infrared communications. In response, the interface unit  16  controls the television  12  via the commercial grade control interface  24 , the format of commands for which may vary among television  12  manufacturers. Finally, the interface unit  16  controls the set top box  14 , via a data transfer link, such as a Universal Serial Bus (USB). The interface unit  16  processor may also run diagnostics and perform other overhead tasks.  
         [0021]     The interface unit  16  additionally receives audio output from the audio out port  28 , and provides the audio to the pillow speaker  18 . In one embodiment, the interface unit  16  includes a galvanic isolation circuit (not shown) to isolate the audio signal from interface unit  16  or television system  10  electrical ground prior to providing it to the pillow speaker  18 . This allows the television control system  10  of the present invention to utilize a commercial grade television  12  (which may not provide galvanic isolation of output audio), rather than the more specialized, and hence more expensive, health care grade television  12  (assuming the commercial grade television  12  otherwise complies with hospital standards).  
         [0022]     The interface unit  16  and pillow speaker  18  are connected by a wired connection  42 . In one embodiment, interposed in the wire  42  between the interface unit  16  and the pillow speaker detain is an optical input port  44 . The optical input port  44  includes an optical receiver, such as a photo diode, and circuits to convert received optical signals to electrical signals, which are forwarded to the interface unit  16 . This allows the television control system  10  to receive control inputs from a variety of wireless optical control devices, such as a conventional IR remote control  46 , optical keyboard  48 , or the like. The optical interface is typically infrared optical, and complies with the RC-5 codes for infrared communications. The infrared communication typically comprises an 880 nm wavelength infrared signal, modulated at 36 KHz. In addition, the pillow speaker  18  may include an accessory jack  50  that provides DC power to, and receives data input from, external accessory devices such as for example a wired keyboard  53  or game controller  54 .  
         [0023]     In operation, the interface unit  16  interprets user input from the pillow speaker  18 , and controls other elements of the television control system  10  to display the user&#39;s desired content on the television  12 , as depicted in the flowchart of  FIG. 2 . The user initially turns the system on via a command from the pillow speaker  18  (block  62 ). In response, the interface unit  16  turns on the television  12 , and directs it to display output from the video input port  32  via commands to the commercial grade control interface  24  (block  62 ). The interface unit  16  additionally directs the set top box  14  to run content selection software, outputting a text or graphical menu to the video input port  32  of the television  12  (block  64 ).  
         [0024]     The user navigates the displayed menu via keys on the pillow speaker  18  to select the desired content (block  66 ). Signals from the pillow speaker  18  are interpreted by the interface unit  16 . If the user selected programming from among that provided by the cable, the interface unit  16  forwards appropriate commands to the commercial grade control interface  24  to display content from the tuner  20  on the display  22  (block  68 ). The interface unit  16  galvanically isolates audio output by the television  12  at the audio output port  28 , selectively amplifies the audio, and provides it to the pillow speaker  18 . The interface unit  16  adjusts the audio level directly, in response to volume up/down commands from the pillow speaker  18 . The interface unit  16  interprets channel selection commands from the pillow speaker  18 , and forwards appropriate commands to the commercial grade control interface  24  to change channels.  
         [0025]     If the user selected other content (block  66 )—such as pay-per-view, instructional video, or other audio-video content; Internet Web browsing; video game playing; or the like—the interface unit  16  forwards the appropriate commands to the set top box  14  to retrieve and display the desired content from the video server  38 , Internet  40 , or other source (block  70 ). The server  34  provides the requested content via the router  36  over a high-bandwidth channel, such as a Local Area Network, to the set top box  14 . The set top box  14  outputs the video and, if present, audio to the television  12 . The interface unit  16  controls the audio volume, and forwards commands to the set top box  14 , in response to signals from the pillow speaker  18 . Interactive signals, such as from the game controller  54  or keyboard  48 ,  52 , are translated and forwarded to the set top box  14 , for relay to the server  34 .  
         [0026]     Regardless of which content the user selects, in one embodiment the interface unit  16  periodically sends a status request command to the set top box  14 , to verify the proper connection and operation of the set top box  14  (block  72 ). This is an ongoing background task, and if the set top box  14  responds, the interface unit  16  continues to monitor the pillow speaker  18  (or other input device  46 ,  48 ,  52 ,  54 ) for command signals and provides the selected content (block  66 ). If the interface unit  16  does not receive a response from the set top box  14  within a time-out period, the interface unit  16  will direct the commercial grade control interface  24  to display content from the cable via the tuner  20 , and will respond to volume changes and channel selection signals from the pillow speaker  18  (block  68 ). In this case, if the set top box  14  had been retrieving content from the server  34 , the server  34  will eventually become aware of no activity from the set top box  14 , and may initiate a maintenance order or other corrective action.  
         [0027]     Although the present invention has been described herein with respect to particular features, aspects and embodiments thereof, it will be apparent that numerous variations, modifications, and other embodiments are possible within the broad scope of the present invention, and accordingly, all variations, modifications and embodiments are to be regarded as being within the scope of the invention. The present embodiments are therefore to be construed in all aspects as illustrative and not restrictive and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.