United States Patent [191
`Moore et al.
`
`[11] Patent Number:
`[45] Date of Patent:
`
`4,566,001
`Jan. 21, 1986
`
`[54] TOUCH STRIP INPUT FOR DISPLAY
`TERMINAL
`[75] Inventors: Timothy G. Moore, Ottawa; David G.
`Dockendorff, Kanata; Stephen J.
`Harris, Ottawa, all of Canada
`
`[73] Asslgnee: :omaem Telecom Lumted’ Montreal’
`ana a
`[21] Appl- N0-: 464,959
`[22] Filed:
`Feb. 8, 1983
`
`[51] Int. Cl.‘ ........................ .. G09G 1/00; GO9G 3/00
`[52] US. Cl. .................................. .. 340/711; 340/706;
`,
`340/709; 340/365 VL; 178/18; 178/19
`Fleld of Search ............. ..
`340/710’ 711’ 365 VL’ 365’ s’ 3 5 ’ 178/1189’
`
`[56]
`
`References Cited
`Us PATENT DOCUMENTS
`
`3,898,643 8/1975 Ettlinger ....................... .. 340/707 x
`4,193,119 3/1980 Arase et a1.
`340/707 X
`4,202,041 5/1980 Kaplow et a1. .
`340/712 X
`
`4,204,204 5/1980 Pitstick , . . . . . . . . . . .
`
`. . . . . . .. 340/712
`
`4,238,792 12/1980 Cohen et a1. ................. .. 340/712 X
`
`4,310,839 1/ 1982 Schwerdt ...................... .. 340/709 X
`Primary Examiner-John W. Caldwell, Sr.
`Assistant Examiner—-Vincent P. Kovalick
`Attorney, Agent, or Firm-Stuart L. Wilkinson
`[57]
`ABSTRACT
`The screen of a display terminal has touch strips extend
`ing adjacent horizontal and vertical edges. The touch
`strips have electrical outputs dependent on the position
`along the strips at which they are touched. Using micro
`processor control the touch strips can be made to ma
`nipulate a displayed image and control the rate or level
`or other terminal functions. By selecting an appropriate
`programming mode the touch strips can be made to
`present a series of programmable or Soft keys‘ Also the
`touch strips can be used to provide a menu selection,
`scrolling and cursor generation and movement for word
`processing. The use of two touch strips requires less
`complex circuitry than a known transparent input over
`la for the dis la screen. Moreover, it is a cleaner
`tezhnique resulrt’ing in reduced image attenuation and
`.
`.
`dlsmmon
`
`18 Claims, 3 Drawing Figures
`
`TCL EXHIBIT 1012
`Page 1 of 6
`
`

`
`US. Patent Jan. 21, 1986
`
`Sheet 1 of2
`
`4,566,001
`
`TCL EXHIBIT 1012
`Page 2 of 6
`
`

`
`U.S. Patent Jan. 21, 1986
`
`Sheet 2 of 2
`
`4,566,001
`
`D12
`:2: AH
`
`gum-uh;
`
`Oh
`
`:12
`
`
`
`nzchm IUDOF
`
`mwioa
`
`.523
`
`mohuudum
`
`TCL EXHIBIT 1012
`Page 3 of 6
`
`

`
`1
`
`TOUCH STRIP INPUT FOR DISPLAY TERMINAL
`
`0
`
`This invention relates to an interactive display termi
`nal.
`An input device for most interactive display terminals
`is a keyboard which typically has an array of alphanu
`meric keys and a number of additional functional keys
`such as shift, erase, etc. To limit the keyboard size, a
`known development of the conventional keyboard has
`several blank or soft keys which can be given any of a
`number of functional designations. Processor control
`enables the functional designation of each soft key to be
`changed if and when desired during use.
`One implementation of the soft key keyboard is used
`in the Displayphone (registered trademark), a combined
`telephone and display terminal marketed by Northern
`Telecom. In the Displayphone, the programmable or
`“sof ” keys are located as a linear series at the rear of the
`keyboard and the currently assigned soft key designa
`tion selected by the user is displayed in the bottom few
`lines of the associated cathode ray tube (CRT) display.
`This equipment is limited to soft keys which are ?xed in
`number and in length of assigned display space. More
`?exibility would be permitted by a variable number of
`25
`variable length soft keys.
`Interactive display terminals are known in which a
`touch sensitive transparent input device overlies the
`whole terminal screen. Such input devices have row
`and column conductors on opposed surfaces. When the
`device is touched a pulsed signal applied cyclically to
`the row conductors appears at a speci?c time on a spe
`ci?c one of the column conductors. From this, the posi
`tion touched is determined and an appropriate output is
`taken to a controlling processor.
`In order to achieve high resolution, the overlay, must
`have a very dense array of conductors on opposed sur
`faces which causes some attenuation and distortion of
`the displayed image. Moreover, because the screen is
`repeatedly touched, dirt and skin oils can also add to
`attenuation and distortion.
`According to the invention there is provided a termi
`nal comprising a display unit having a display screen,
`and a position sensitive touch strip extending along an
`edge of the screen, the touch strip having an output in
`response to its being touched by a user, the nature of the
`output being dependent on the distance along the strip
`of the position touched by a terminal user.
`The display screen can be of rectangular form having
`the touch strip extending along one edge. A second
`touch strip can be mounted to extend along an adjacent
`edge of the screen in a direction perpendicular to the
`direction in which the ?rst touch strip extends. The
`strip or strips can be mounted at positions offset from
`the screen. Alternatively touch strips can be mounted
`on a bezel surrounding the screen. In another alterna
`tive, the touch strip can be mounted on the screen but at
`a location so as not unduly to distort or block a dis
`played image.
`Preferably the touch strip has an analog output, the
`analog output taken to an analog-to-digital converter to
`provide an encoded digital output to a processor for use
`in controlling the display. For example a touch strip
`functioning as a voltage divider, can have a strip of
`resistive material spaced from a strip of conductive
`65
`material, means for establishing a voltage gradient
`along the resistive strip, means maintaining the strips
`spaced apart unless the touch strip is pressed to establish
`
`4,566,001
`2
`electrical contact between the conductive and resistive
`strips some distance along the touch strip. The voltage
`at the selected location on the resistive strip is trans
`ferred to the conductive strip and appears as an input to
`the analog-to-digital converter.
`An embodiment to the invention will now be de
`scribed by way of example, with reference to the ac
`companying drawings in which:
`FIG. 1 shows a perspective view of a terminal ac
`cording to the invention;
`FIG. 2 is a part perspective, part schematic view of
`one form of touch sensitive strip; and
`FIG. 3 is a block schematic diagram showing the
`operation of the FIG. 1 terminal;
`Referring firstly to FIG. 1, the terminal illustrated
`has a cathode ray tube (CRT) unit 10 with a rectangular
`screen 12. In front of the screen is a keyboard 14 which
`has a conventional set of alphanumeric keys and a num
`ber of additional functional keys such as shift and erase.
`Extending horizontally and vertically along two edges
`of a bezel surrounding the rectangular screen are touch
`sensitive strips 16 and 18 respectively. The vertical and
`horizontal touch strips are of identical construction and
`in use each has a voltage output which is representative
`of the distance along it at which it is touched.
`Referring in detail to FIG. 2, each of the touch strips,
`which operate on a voltage dividing principle has a
`?exible conductive strip 20 overlaying a resistive sub
`strate 22. The conductive strip and the substrate are
`normally separated from one another by an insulating
`frame 24 but can be locally brought together by press
`ing the strip downwardly at a desired location along the
`strip. A voltage gradient is established along the resis
`tive substrate by applying voltages V+, and V
`through resistors R to electrodes contacting the sub
`strate ends.
`As shown schematically in FIG. 3 the touch strip has
`a power supply to establish the voltage gradient along
`the resistive substrate. The output of the touch strip is
`taken to the input of a ?lter/buffer unit and the output
`of the ?lter/buffer unit is taken to one input of an ana
`log-to-digital converter. The analog-to-digital con
`verter operation is controlled by a select/control logic
`circuit which is driven by timing impulses from a clock
`circuit. The operation of the clock circuit is determined
`by an interface circuit which also loads data from the
`analog-to-digital converter into a microprocessor unit.
`Outputs from the microprocessor unit are used to con
`trol operation of the touch strip input circuit and also to
`alter terminal functions in response to the strip being
`touched. Generally the control exercise by the micro
`processor unit is divided into a generation of image data
`and the operation of control functions such as control
`ling the volume, rate or level of certain parameters of
`the image and other terminal functions.
`An output voltage representing a position touched on
`the touch strip is monitored as the difference between
`potentials V6 and V1,. The monitored potential differ
`ence is received at the ?lter/buffer circuit which moni
`tors when a contact has been initially made at the touch
`strip, ascertains whether that contact is truly a deliber
`ate actuation of the touch strip, and generates a voltage
`representing the position touched on the strip. The time
`constant of the ?lter circuit is appropriately set so as to
`register most strip actuations which are deliberate and
`so as not to register most of the touch strip contacts
`which are unintended.
`
`30
`
`35
`
`40
`
`45
`
`TCL EXHIBIT 1012
`Page 4 of 6
`
`

`
`0
`
`20
`
`3
`In order for the microprocessor unit to accept data
`from the touch strip, the strip must be calibrated so that
`the range of monitored voltages |Vc—V1,| and the
`corresponding relationship to input data is known.
`Because the operator’s ?ngers are relatively broad,
`?nger contact resolution is typically within 1 centimeter
`whereas sampling resolution can be as high as 10 units
`per centimeter. Consequently, while a contact is made
`many values within a range of about 10 units can be
`generated. To avoid an input error at the microproces
`sor, previous values generated by the strip are stored
`and the difference between the stored and current input
`values are computed. If this difference is greater than a
`preset magnitude then a new value from the strip is
`generated and is either stored in a memory location to
`be polled by the microprocessor or generates a software
`interrupt.
`’
`The touch strips‘ can be used in a variety of ways
`depending on the manner in which the microprocessor
`is programmed. In order to select the desired program
`one of the functional designation keys in the primary
`keyboard is pressed. Typical functional keys associated
`with the touch strips are soft-key designation, menu
`selection, cursor generation, graded control and scroll
`mg.
`For the soft-key designation the microprocessor is
`programmed to permit a touch strip to be notionally
`divided into a selected number of selected width indi
`; vidual keys. After pressing soft-key designation func
`tion key of the primary keyboard, the user presses an
`~ other key to indicate the ?rst or left-hand soft key is
`-' about to be selected, establishes the identity of that soft
`-- key, for example, DATE, by using the alphanumeric
`keyboard. Lastly the user establishes a key length both
`on the touch strip and within the associated display if
`the key designation is to be illustrated on the display.
`Optionally, the user can establish a neutral or spacer
`section between adjacent assigned key intervals within
`-~the touch strip before going on to program the second
`and subsequent selections along the touch strip. Once
`40
`vprogrammed, the terminal operator uses the terminal as
`" if the touch strip were divided into a number of separate
`keys functioning essentially as an extension of the ?xed
`keyboard.
`By pressing the menu selection function key, a pro
`gram is selected which enables the user to select one
`title from a list of displayed titles merely by pressing the
`touch strip (usually the vertically extending touch strip)
`at a location adjacent to the particular displayed title.
`Once having selected this title from the list the user then
`can perform any of a number of manipulating functions,
`for example displaying a further set of possible selec
`tions within the broad title selected.
`When the cursor generation program is selected by
`pushing the appropriate functional key, a cursor is gen
`erated at a reference position in the terminal display the
`cursor being usable for many functions as is well known
`in the word processing art. In contrast to the soft-key
`and menu selection functions which enable selection
`along the screen width or the screen height, cursor
`manipulation depends upon pressing contacts at both
`strips to establish a position on the screen area. As with
`the linear applications, calibration or assignment of a
`mapping factor must be undertaken. For each of the
`vertical and horizontal strips the mapping factor,
`M=screen range>< l/strip range. To reposition the
`cursor from the reference to a selected position, the two
`touch strips are touched at positions corresponding to
`
`4,566,001
`4
`the XY co-ordinates of the selected position. Once the
`XY co-ordinates have been assigned, the cursor is auto
`matically transferred from the reference to the selected
`display position. A word processing function is then
`performed. Part of the function may require movement
`of the cursor using the lateral touch strip. Once com
`pleted, the cursor is removed to the reference or an
`other selected position by appropriately activating the
`horizontal and vertical touch strips.
`By pressing the graded control key and an appropri
`ate character key, one or both of the touch strips can be
`used to control a continuously varying quantity. Exam
`' ples are sound volume (for telephone ringing or voice)
`and display brightness, contrast or colour determinants.
`Again, using a touch strip to control a level or rate, it
`is necessary to map values from the strip to values that
`are in the range of possible levels or rates. Here the
`mapping factor M=a range of levels or ratesX l/strip
`range.
`By pressing the scrolling key, the terminal is pro
`grammed to permit the displayed text or graphics to be
`moved vertically or laterally to display adjacent parts
`of the displayed matter of which the currently dis
`played ?eld is just a part stored in memory. To operate
`the terminal in this mode, the user merely strokes the
`touch strips along their length in the direction in which
`the displayed ?eld is to move.
`Although the invention has been described in terms
`of two touch strips along respective adjacent edges of a
`display terminal screen, it will be appreciated that touch
`strips may extend along all the edges of the screen.
`Moreover, if desired, a bank of such touch strips can be
`mounted along each edge. In this latter case keys associ
`ated with the functional keyboard must permit switch
`ing between different ones of the banks of strips.
`Although for simplicity the preferred form of touch
`strip uses a voltage dividing network and associated
`monitoring circuit, each of the touch strips may instead
`be embodied as a linear array of discrete touch sensitive
`areas, for example of capacitative character. When such
`a touch sensitive area is touched by the terminal user a
`corresponding input to a multiplexer changes state. A
`counter is operated to cycle through the addresses of
`the multiplexer and when an address corresponding to a
`touched area is generated an output from the multi
`plexer enables a buffer whereby the current counter
`output is transferred to the microprocessor.
`What is claimed is:
`1. A terminal comprising a rectangular display
`screen, display means for displaying an image on the
`screen, a position sensitive touch strip spaced from the
`screen, mounted along one side thereof and extending
`the length of the screen, voltage generating means for
`generating a voltage level in response to the touch strip
`being touched, the voltage level corresponding to the
`position at which the strip is touched, a selector for
`selecting one of a plurality of possible display modes, an
`input interface unit having inputs from said voltage
`generating means and from said selector, a microproc
`essing unit having an input from the input interface unit
`and an output to an output interface unit, the output
`interface unit having an output controlling said display
`means, the microprocessing unit having stored therein a
`control program which determines the display mode in
`response to an input from the selector and determines
`image detail in response to an input from the voltage
`generating means.
`
`25
`
`30
`
`45
`
`65
`
`TCL EXHIBIT 1012
`Page 5 of 6
`
`

`
`10
`
`15
`
`25
`
`30
`
`35
`
`4,566,001
`6
`5
`the control program prepares the microprocessing unit
`2. A terminal as claimed in claim 1 wherein in re
`to receive cursor positional data and instructs the dis
`sponse to a selectable output from the selector, the
`control program de?nes both a plurality of individually
`play means to generate a cursor in the displayed image,
`energizable discrete lengths within the touch strip, and
`the control program further responding to inputs from
`a corresponding plurality of regions of the display
`the touch strips to drive the display means to alter the
`cursor position on the screen in directions parallel to the
`screen.
`strips.
`3. A terminal as claimed in claim 2 wherein the con
`trol program functions to preclude input data originat
`9. A terminal as claimed in claim 1 in which the
`ing when the touch strip is touched other than at posi
`screen is surrounded by a frame and the touch strip is
`tions within said discrete lengths.
`mounted on the frame.
`4. A terminal as claimed in claim 1, the terminal par
`10. A terminal as claimed in claim 1 in which the
`ticularly adapted for a display operating mode in which
`touch strip is mounted by means of an adhesive.
`the display depends on a continuously variably operat
`11. A terminal as claimed in claim 1 in which the
`ing parameter, the terminal further comprising control
`frame projects forwardly of the screen, the touch strip
`means for controlling the value of the variable operat
`located on an edge of the frame immediately adjacent to
`ing parameter, and wherein in response to a selected
`the screen.
`12. A terminal as claimed in claim 1 in which the strip
`output of the selector, the control program initiates an
`is mounted on a control panel angled relative to the
`output to select said control means and in response to an
`output of the touch strip, the control program initiates
`screen.
`13. A terminal as claimed in claim 1 in which the
`an output to the control means to drive the value of the
`screen is of rectangular form and the touch strip extends
`parameter to a value corresponding to the position at
`along one edge thereof.
`which the touch strip is touched.
`5. A terminal as claimed in claim I particularly
`14. A terminal as claimed in claim 2 in which the
`discrete lengths of the touch strip correspond in length
`adapted for a scrolling display operating mode wherein,
`and position to the plurality of regions in the screen
`in response to a selected output of the selector, the
`adjacent to the touch strip designations and the screen
`control program prepares the microprocessing unit to
`regions.
`receive scrolling data, the control program further re
`sponding to an input from the touch strip corresponding
`15. A terminal as claimed in claim 4 in which the
`to unidirectional stroking thereof to drive the display
`variable operating parameter is one of the group con
`sisting of image brightness, image colour, and image
`means to scroll the displayed image.
`scale.
`6. A terminal as claimed in claim 1 in which said
`touch strip is mounted at a location spaced from said
`16. A terminal as claimed in claim 14 in which the
`screen regions extend along a marginal portion of the
`side of said screen.
`screen immediately adjacent to the touch strip.
`7. A terminal as claimed in claim 1 in which a second
`touch strip extends along another side of the rectangu
`17. A terminal as claimed in claim 16 in which the
`lar screen in a direction substantially perpendicular to
`display is of the raster scan type in which a frame con
`the direction in which the ?rst touch strip extends, the
`sists of a plurality of horizontal scan lines, the touch
`strip being horizontal and the screen regions occupying
`terminal including a further voltage generating means
`for generating a voltage in response to the second touch
`a plurality of lines at the end of the raster scan.
`strip being touched, the second voltage level corre
`18. A terminal as claimed in claim 16 in which the
`display is of the raster scan type having a plurality of
`‘ sponding to the position at which the second strip is
`horizontal scan lines, the touch strip extending verti
`touched.
`cally and the screen regions occupying vertically
`8. A terminal as claimed in claim 7 particularly
`adapted for a display operating mode using a cursor
`aligned parts at one end of the raster scan lines.
`* i * i t
`wherein in response to a selected output of the selector,
`
`“
`
`45
`
`50
`
`55
`
`65
`
`TCL EXHIBIT 1012
`Page 6 of 6