Abstract:
A light responsive data entry system includes a panel having a plurality of data entry areas for transmitting light incident on a surface of the panel to a sensor having an array of light responsive areas through a plurality of optical conductors extending between the panel and the sensor. The sensor is capable of generating output signals representative of incidence of the light on said light responsive areas.

Description:
BACKGROUND  
         [0001]    Various home and workplace mechanical units such as printers, scanners, facsimile machines, document copiers and units which combine various of these and other functions, as well as many other types of equipment including machinery, automotive and equipment for various purposes, require a data entry keypad for controlling the equipment. These keypads include moveable buttons and bars which are expensive to construct. A reliable and less expensive data entry keypad is therefore desired.  
         SUMMARY  
         [0002]    Disclosed herein is a data entry system comprising a panel having a plurality of data entry areas for transmitting light incident on a surface of said panel to a sensor having an array of light responsive areas thereon through a plurality of optical conductors extending between said panel and said sensor, said sensor being capable of generating output signals representative of incidence of light on said light responsive areas. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0003]    [0003]FIG. 1 is a schematic side elevation view of a document scanner having a stationary light sensor.  
         [0004]    [0004]FIG. 2 is a schematic side elevation view of a portion of FIG. 1  
         [0005]    [0005]FIG. 3 is a plan view of the keypad seen in FIG. 1.  
         [0006]    [0006]FIG. 4 is a schematic side elevation view of a document scanner having a moveable light sensor.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0007]    Embodiments of the present invention relate to a data entry system which is useful in various office equipment including, but not limited to, document handling equipment such as printers, scanners, facsimile machines, document copiers and units which combine various of these functions. Embodiments of the invention will be described in the context of a document scanner but the details and concepts disclosed herein are broadly applicable to a much wider variety of equipment.  
         [0008]    [0008]FIG. 1 depicts a simplified side elevation of a scanner in which the document to be scanned, which may comprise a sheet of printed media, follows a straight-through path in the scanner  2  from an input device  4 , which may comprise an inclined tray or an automatic single sheet feeder to an output tray  6 . A sensor  8  detects the presence of a media sheet loaded in the input device  4 . In response to the detection of printed media, pick-up rollers  10  pull the media onto a transparent surface  12  which supports the media sheet during scanning of the image(s) printed thereon. An illumination source  14 , which may comprise an array of different colored LEDs or a fluorescent lamp, directs light onto a mirror  16  which in turn reflects the light onto the media as it moves over the transparent surface  12 . A lens  18  focuses light reflected from the surface of the media onto an optical sensor  20  which may comprise an array of charge coupled devices (CCD) or charge image sensors (CIS). The sensor  20  senses the image formed from the light reflected off the surface of the printed media in order to generate electrical signals representing the image on the surface of the printed media, these signal in turn being fed to a storage device  26  which stores digital data representative of the scanned image. After the sheet is scanned, it is grasped and moved to the output device  6  by suitable means such as opposed rollers  22 ,  24 .  
         [0009]    The data entry keypad  30  seen in enlarged elevation view in FIG. 2 and in plan view in FIG. 3 is comprised of an array of light transmitting key areas  32  which may be used for alphanumeric data entry, for turning the equipment on and off or for other control functions. The key areas may be arranged in any suitable configuration such as a rectangular pattern as shown in FIG. 3 and any desired number of key areas  32  may be provided. The panel  30  is preferably fabricated of plastic or lightweight metal with apertures at the key areas  32 . A translucent or transparent cover layer  34  of plastic or glass may be bonded to the panel  30  to cover the key areas  32  for protection from the ingress of dirt and other foreign materials. The data entry keypad  30  may alternatively comprise a LCD display having translucent or transparent key areas in a polarizable panel. Such LCD panels may normally be opaque and selected areas thereon may be polarized to translucent or transparent when desired. These properties of LCD displays are particularly useful to display desired user interface information on key areas  32  and non-key areas of the keypad  30  of a multi-function unit such as a facsimile/copier/printer.  
         [0010]    Light incident on the cover layer  34 , which may be ambient or from a provided separate source, described below, is transmitted through each of the key areas  32  to an associated optical conductor or light pipe  40  having an input end  42  positioned in light transmitting proximity to the inner surface of the respective key area  32  and an output end  44  positioned to direct ambient light transmitted from the key areas  32  onto selected data entry locations  21  on the light receptive surface of the optical sensor  20 . Those skilled in the art will understand that the optical sensor  20  includes an adequate number of light responsive areas for receiving the scanned image as well. Interruption, or reduction of the incident light detected by the sensor  20  is caused by coverage of the chosen key areas  32  with fingers or other objects during entry of data. Thus, entered data is transmitted to the storage device  26  by output signals provided by the optical sensor in response to detected reductions in the incident light ordinarily transmitted by the light pipes  40 . The routing of the light pipes  40  from the keyboard  30  to the optical sensor panel  20 , may be done in alternative ways, although it may be desirable to reduce the length, vibration and bending of the pipes  40 . FIG. 1 schematically shows routing of a bundle  48  of light pipes  40 . The use of an inexpensive keypad  30  having light transmitting key areas  32  and optical conductors or light pipes  40  to transmit incident light to the existing CCD/CIS array of the optical sensor  20  which is then useful for data entry purposes is a cost effective and significantly advantageous concept particularly for low end document handling equipment such as scanners.  
         [0011]    The data entry keypad  30  and light conductors  40  can easily also be used in scanners of the type shown in FIG. 4 which have a manually moveable lid  28  to hold down a media sheet placed on the transparent surface  12 . This form of scanner holds the document in a stationary position during scanning and uses a moveable scanner bar incorporating the optical sensor array  20 . The scanner bar and sensor  20  is mounted in any suitable manner such as on spaced guides  50  and may be parked proximate the keypad  30  near the light discharge ends  44  of the light conductors  40  when data is entered.  
         [0012]    Since ambient light conditions vary from place to place and at different times of the day, a source  52  of supplemental light may be provided for an essentially constant amount of illumination to the data entry side of the keyboard  30  during data entry. The light source  52  can be automatically actuated in any suitable fashion, such, for example, as when the lid  28  is opened or the machine is switched on. The source  52  may comprise an individual light or lights or suitable optical conduit (not shown) for conducting light from an existing source of illumination in the apparatus such as the source  14  seen in FIG. 1 to illuminate the outer surface of the keypad  30 . The source may comprise, for example, a side illuminated LCD screen.  
         [0013]    Persons skilled in the art will also appreciate that various modifications can be made from the specific embodiments shown and described above.