Patent Publication Number: US-2005140725-A1

Title: Video display device with onboard hardcopy capability

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
      This is a Continuation application of U.S. Ser. No. 10/949,292 filed on Sep. 27, 2004, which is a Continuation of Ser. No. 10/432,956 filed on May 29, 2003, now issued U.S. Pat. No. 6,799,853 which is a 371 of PCT/AU01/01512 filed on Nov. 22, 2001 the entire contents of which are herein incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION  
      The following invention relates to a data projector with an internal printer. More particularly, though not exclusively, the invention relates to a data projector having a pagewidth drop on demand ink jet printhead and a source of print media located in the projector body.  
      It is known to make presentations to a group of people using a data projector connected to a portable computer. Using appropriate software, the portable computer can generate a sequence of text and/or graphic images for projection upon a screen using the projector.  
      The portable computer might also be connected to a printer. However, if a member or members of the group require a printout of an image on a screen, printer driver software must be activated by the operator of the portable computer. Usually, a printer driver-associated window appears in the screen to report the status of any printing request. Such a window would be disruptive to the overall presentation as it would appear on the image being projected onto the screen. This would be disruptive, particularly if only one person of the group required a printout.  
      The attachment of a separate printer to the portable computer would also be generally inconvenient as there would be separate cabling required between the computer and the printer and the printer would need a power supply, possibly requiring the use of an electrical double adaptor or the like.  
     OBJECTS OF THE INVENTION It is an object of the present invention to overcome or substantially ameliorate at least one of the above disadvantages.  
      It is another object of the present invention to provide a data projector having an in-built printer.  
      It is a further object of the present invention to provide a simple means of printing a “screen dump” of a displayed image without the necessity of cabling in addition to that which would normally be necessary to operate the data projector with a portable computer.  
      It is yet another object of the present invention to provide a means of enabling a printed “screen dump” of an image projected by a data projector without that image being altered by any printer-driver software.  
     DISCLOSURE OF THE INVENTION  
      According to the invention, there is provided a data projector that comprises projector control circuitry for receiving analogue data signals from a computer-based machine representing images to be projected at a viewing surface;  
      an analogue to digital converter connected to the control circuitry for receiving the analogue data signals from the control circuitry and for converting said signals into digital signals;  
      a printhead for printing images represented by the digital signals; and  
      printer control circuitry for controlling operation of the printhead and delivery of data to the printhead.  
      A memory device may be interposed between the printer and the converter to store digitized data received from the converter.  
      The memory device may be a digital frame store.  
      The printer control circuitry may include a print engine controller that is connected to the printhead to receive data from the memory device.  
      The printer control circuitry may include a micro-controller to provide the print engine controller with print activation signals.  
      The data projector may include an actuation device that is connected to the micro-controller to permit an operator to control operation of the printhead.  
      There is disclosed herein a data projector for projecting images at a viewing surface, the data projector including a built-in printer for printing an image projected by the projector. Preferably the data projector receives video information from a portable computer.  
      Preferably, the data projector includes an activator to activate a print request.  
      Preferably, the activator is a button on the data projector.  
      Alternatively, the activator is a keypad on the data projector.  
      Alternatively, the activator includes a signal receiver on the data projector associated with a remote signal transmitter.  
      Preferably the signal receiver and/or transmitter use infrared data transmission.  
      Preferably the data projector has means for storing a supply of print media therein.  
      Preferably integrated with and/or associated with circuitry in the projector is an analogue to digital converter to convert analogue image data into digital form.  
      Preferably the digital form of the image is stored in a frame store.  
      Preferably the projector also has built into it a print engine control chip receiving information from the frame store and sending that information to a printhead upon instruction from the activator.  
      Preferably a micro-control circuit controls information from the frame store to the print engine control chip.  
      Preferably the printhead is a pagewidth printhead such as that described in greater detail in our co-pending applications U.S. Ser. No. 09/575,115 and U.S. Ser. No. 09/575,141. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      A preferred form of the present invention will now be described by way of example with reference to the accompanying drawings wherein:  
       FIG. 1  is a schematic illustration showing an association between a data projector having an in-built printer and a portable computer, and  
       FIG. 2  is a schematic block diagram including circuity built into the data projector to enable an image projected thereby to be printed. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
      In  FIG. 1  of the accompanying drawings there is schematically depicted a data projector  10  interconnected with a portable computer  17  by means of a “VGA” cable  16 . Cable  16  relays analogue video signals from the portable computer  17  to the projector  10 . These signals would typically be “VGA” or Video Graphic Adaptor signals or signals providing a higher resolution image such as “SVGA” or Super Video Graphic Adaptor signals or the like.  
      Typically, cable  16  is the only cable extending between computer  17  and projector  10 . However, if a desktop computer is used, a power supply cable might also extend from the computer to the projector.  
      The projector  10  includes a lens  11  by which an image is projected upon a screen.  
      Located within the housing of projector  10  is a printer including a printhead  23  and a store of print media (not shown). The print media would typically be A4 sized paper.  
      In order to activate a printing operation so as to produce a printout or “screen dump” of an image projected by lens  11 , one of several activators is provided. For example, a single print button  13  might be provided or a keypad  12 . As a further option, an infrared detector  24  might be provided.  
      Where a single print of an image being projected is required, button  13  might be depressed. As a result, a sheet  14  would be produced by the printer. It might be desirable to produce a printout of every image of a sequence of images projected by the projector  10  and/or multiple copies of a single image for distribution to several people. This might be accommodated by pressing certain keys or combinations of keys on keypad  12 .  
      The presenter of a presentation being projected by the projector  10  might hold an infrared remote control unit. Depression of a key or keys on that unit could transmit a signal to be read by infrared receiver  24  to produce the same effect as single button  13  or the keypad  12 . More complex signals such as those required to achieve the same effect as pushing a key or combination of keys on keypad  12  might also be transmitted by an infrared remote control unit to the receiver  24 .  
      With reference to  FIG. 2 , there is shown the computer  17  transmitting analogue video signals via cable  16  to projector circuitry  18  situated within projector  10 . Associated with that circuitry or added thereto is an analogue to digital converter  19  converting analogue image data into digital form for storage in a digital frame store  20 . That is, frame store  20  would hold at any given time digital information equivalent to an analogue image projected by lens  11 .  
      The output of information from frame store  20  can be received by a print engine control chip  22  to control printhead  23  situated within the projector housing. A micro-control  21  receives an activation signal from one of activation devices  12 ,  13  or  24  to instruct the print engine control chip to control the printhead so as to print a frame stored in frame store  20 .  
      The printhead  23  would typically be a pagewidth printhead of the type disclosed in our co-pending applications U.S. Ser. No. 09/575,115 and U.S. Ser. No. 09/575,141.  
      Associated with the printhead would be a print media transportation mechanism and platen across which the sheets would be driven whilst receiving printed information prior to dispensing from the projector housing as shown in  FIG. 1 .  
      It should be appreciated that modification and alterations obvious to those skilled in the art are not to be considered as beyond the scope of the present invention. For example, rather than incorporating the printer mechanism into a data projector, it could be incorporated into any video display device.