`
`Filed Aug. 2, 1966
`
`E. A. Johnson
`TOUCH DISPLAYS
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`3,482,241
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`3. Sheets-Sheet l
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`4-4. As 1-4.
`torneys
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`Petitioner Exhibit 1022, Page 1
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`
`
`Dec. 2, 1969
`
`Filed Aug. 2, 1966
`
`E, A.JOHNSON
`TOUCH DISPLAYS
`
`3,482,241
`
`3. Sheets-Sheet 2
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`Attorneys
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`Petitioner Exhibit 1022, Page 2
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`
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`Dec. 2, 1969
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`Filed Aug. 2, 1966
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`9
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`REASSESSMENT
`OR
`REVALUATION
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`
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`E. A. JOHNSON
`TOUCH DISPLAYS
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`3,482,241
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`3. Sheets-Sheet 5
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`3
`CONTROL OF PLANT
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`5
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`DATA INPUT
`FROM SENSORS
`DATA INPUT FROM
`OTHER OPERATORS
`7
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`NEW DISPLAY 9
`OF CHOICES
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`3
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`OPERATOR
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`PAST EXPERENCE
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`SENSES (SIGHT, HEARING)
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`5
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`INDICATES
`CHOICE
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`F.G. S.
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`Anventor
`Ae/c/27%f deasey
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`4.444 vé-A-
`
`orneys
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`Petitioner Exhibit 1022, Page 3
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`
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`United States Patent Office
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`3,482,241
`Patented Dec. 2, 1969
`
`1
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`3,482,241
`TOUCH DISPLAYS
`Eric Arthur Johnson, Malvern, England, assignor to
`Minister of Aviation in Her Britannic Majesty's
`Government of the United Kingdom of Great
`Britain and Northern Ireland, London, England
`Filed Aug. 2, 1966, Ser. No. 569,731
`Claims priority, application Great Britain, Aug. 5, 1965,
`33,524/65; June 28, 1966, 28,883/66
`Int, C. G09b 13/00, H05b 41/00; G06k I/00
`U.S. C. 340-337
`7 Claims
`
`ABSTRACT OF THE DISCLOSURE
`A plurality of touch-sensitive contacts, placed adjacent
`the "screen of a cathode ray tube, which may be selec
`tively actuated for indicating which portion of the image
`on the cathode ray screen is to be exmained in further
`detail. The position of the actuated contact with respect
`to the viewing screen indicates which portion of the
`image has been selected to an output means such as
`a data processing system. Either resistance change or
`capacitance change across the actuated contact may be
`sensed.
`
`The presnet invention relates to touch displays.
`A very large number of so-called automatic data proc
`essing systems require the co-operation of human opera
`tors to achieve satisfactory operation. In many of these
`systems it is necessary to reduce operator reaction time
`to a minimum, which in turn demands an arrangement
`where communciations between the operator and the
`system and vice versa is the best possible. This requires
`that the methods of presenting information to and re
`ceiving instructions from the operator should be rapid
`and easy.
`For the presentation of information to the operator,
`a method often used at the present time is some form
`of printing, usually electromechanical. Although the
`normal teleprinter output is rather slow in relation to
`the speed with which an operator can absorb informa
`tion, an extension of the technique to line printing cn
`overcome this. Alternatively an electronic data display is
`sometimes used, and in the case of line printing or elec
`tronic data display time required to produce a readable
`output from the system does not really add significantly
`to the time required for an operator to accept informa
`tion. There is also a considerable amount of flexibility
`of format available to ease understanding.
`The situation is not so satisfactory in the case of
`accepting instructions from an operator. A current
`method is to make use of some form of keyboard with
`either a standard set of alpha-numeric keys or some
`special keys, usually called function keys, or both. The
`function keys as their name implies, usually provide con
`trol instructions to the system whilst the alpha-numeric
`keybord is used for information input, interpreted by
`the system in acocrdance with the most recent control
`instructions. The process can be rather slow and clumsy
`especially when a fairly large system is involved with
`several operators having a wide range of input possibili
`ties in the interests of flexibility.
`It is an object of the invention to provide means for
`feeding data (instructions or information) to a system
`by using a touch display by means of which means re
`sponsive to touch are associated with a display. The
`means responsive to touch may be connected to a data
`input of the system.
`According to the present invention there is provided,
`for use with means for displaying data, means responsive
`to touch having an output indicative of the area touched.
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`The means responsive to touch may include a transparent
`Screen responsive to touch suitable for fixing in front of
`the means for displaying data.
`Preferably the means responsive to touch is connected
`to a data input of a data processing system. In such a
`case it is highly advantageous for the means for display
`ing data to be connected to a data output of the data
`processing system in such a manner that the data dis
`played may be altered under the control of the data
`processing system.
`A convenient means for displaying data is, of course,
`provided by the cathode ray tube, which may be con
`trolled to write output information on its screen; the
`invention provides a method of feeding more information
`to the data processing system, so continuing the pro
`gramme. For example, the cathode ray tube may display
`a list of items and it may be desired to examine one of
`the items in further detail. It is frequently troublesome
`to indicate to the data processing system which item is
`the one to be examined. Under these circumstances it
`should be possible to provide sites on the cathode ray
`tube which are responsive to touching by the hand of
`the operator. The effect would be that the operator
`touches the place on the cathode ray tube screen where
`the item is displayed and this signals back to the data
`processing system that that particular item is selected
`(for further examination, Say).
`Such a system may be arranged by embedding elec
`tric wires in the screen, one to each site on the cathode
`ray tube, and using the operator's natural capacitance
`30
`to earth, which is of the order of 100 pf.
`In an alternative arrangement a pair of wires may be
`arranged close to one another and the operator's finger,
`touching the two wires, would short them out via the
`natural skin resistance of the finger plus the contact re
`sistance, which is of the order of 500,000 ohms.
`Embodiments of the invention will be described by
`way of example with reference to the accompanying
`drawings, in which:
`FIGURE 1 is a circuit diagram of a touch sensitive
`system;
`FIGURE 2 is a more complete circuit diagram of
`part of a display incorporating a touch-sensitive system;
`FIGURE 3 is a circuit diagram of part of an alter
`native display incorporating a touch sensitive system;
`FIGURE 4 is a circuit diagram of part of a further
`alternative display incorporating a touch sensitive sys
`tem; and
`FIGURE 5 is a diagrammatic representation of the
`logic steps taken in a process using a data processing
`system and input and output facilities.
`In FIGURE 1 the primary winding of a transformer
`T1 is fed from a high frequency source S (say 3000
`cycles per second) and the secondary winding is centre
`tapped. One half L1 of the secondary winding is con
`nected bteween the centre tap CT1 and a terminal con
`nected to earth via a variable capacitor C1 and a varia
`ble resistor R1 in series and the other half L2 of the
`Secondary winding is connected between the centre tap
`CT1 and a sensitive electrode SE1. The centre tap CT1
`is connected to earth via the primary winding L3 of a
`transformer T2.
`The action of the circuit is as follows. The windings
`L1 and L2, together with the capacitor C1 and the
`resistor R1, and the self capacity of the sensitive elec
`trode SE1 form a bridge circuit which is adjusted to
`be balanced at the frequency fo of the source S. When
`the sensitive electrode SE1 is touched by an operator
`the capacitance to earth presented to it is sufficient to
`throw the bridge off balance and an alternating poten
`tial appears across the winding L3 and hence a signal ap
`pears in the Secondary winding of the transformer T2.
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`FIGURE 4 is a circuit diagram of part of a further
`In FIGURE 2 an electronic data display includes a
`alternative display incorporating a touch sensitive system.
`matrix M of sensitive electrodes SE1, SE2, . . . , two
`This is an alternative way of using the skin resistance
`of which are connected (via screened cable) to the end
`of the operator's finger to unbalance bridge circuits.
`terminals of the transformer T1. One of the end terminals
`(depending on the stray capacities) of the secondary
`A matrix of pairs of sensitive electrodes SP00, SP01,
`winding of the transformer T1 is connected to earth via
`SP02, SP03, SP10, SP11, SP12, SP13, SP20, SP21, SP22,
`the capacitor C1 and the resistor R1 in series. The centre
`SP23, SP30, SP31, SP32 and P33 is connected in rows
`to the secondary windings of two transformers T4 and
`tap CT of the secondary winding of the transformer
`T1 is connected to earth via the primary winding of
`T5 in the following manner. One terminal of the second
`ary winding of the transformer T4 is connected to the
`the pulse transformer T2, as before. The secondary wind
`upper electrode of each of the pairs. P00, SP.01, SP02
`ing of the transformer T2 is connected to a phase control
`unit P the output of which is connected to a phase sensi
`and SP03 of sensitive electrodes in the first row, the
`other terminal of the secondary winding of the trans
`tive detector PSD via an amplifier/limiter. The output
`former T4 is connected to the upper electrode of each
`of the phase sensitive detector PSD is applied to a com
`puter K which has an output applied to the display
`of the pairs SP10, SP11, SP2 and SP13 of sensitive
`electrodes in the second row, one terminal of the second
`control DC.
`ary winding of the transformer T5 is connected to the
`The action of this circuit differs from that of the circuit
`upper electrode of each of the pairs SP20, SP21, SP22
`described with reference to FIGURE 1 in the fact that
`the bridge circuit R1-C1-T1 secondary-T2 primary may
`and SP23 of sensitive electrodes in the third row, and
`the other terminal of the secondary winding of the trans
`be unbalanced by touching either of the sensitive elec
`former T5 is connected to the upper electrode of each
`trodes SE1 or SE2. In each case the result will be an
`output from the transformer T2 but the phase relation
`of the pairs SP30, SP31, SP32 and SP33 of sensitive
`ship of this output with the supply current S will be
`electrodes in the fourth row.
`Similarly the matrix is connected in columns to the
`different for the two different electrodes SE1 and SE2.
`primary windings of two transformers T6 and T7 in
`The function of the phase control P is to ensure that
`the signal is in the correct phase to ensure a suitable
`the following manner. The lower electrode of each of
`output from the phase sensitive detector after allowing
`the pairs SP.00, SP10, SP20 and SP30 of sensitive elec
`for stray phase shift throughout the system. The output
`trodes in the first column is connected to one terminal
`of the transformer T2 is applied from the phase control
`of the primary winding of the transformer T6, the lower
`P to the amplifier A and thence to the phase sensitive
`electrode of each of the pairs SP01, SP11, SP21 and
`detector PSD where its phase is compared with that of
`SP31 of sensitive electrodes in the second column is con
`the supply current S. The phase sensitive detector PSD
`nected to the other terminal of the primary winding of
`has two outputs and these will therefore correspond sepa
`the transformer T6, the lower electrode of each of the
`rately to the two separate sensitive electrodes SE1
`pairs SP02, SP12, SP22 and SP32 of sensitive electrodes
`in the third column is connected to one terminal of the
`and SE2.
`Thus an output, indicating which sensitive electrode is
`primary winding of the transformer T7 and the lower
`touched, is applied to the computer K, where it is used
`electrode of each of the pairs SP03, SP13, SP23 and
`typically to set up a fresh display via the display con
`SP33 of sensitive electrodes in the fourth column is con
`nected to the other terminal of the primary winding of
`trol DC.
`The remaining electrodes (SE3, etc.) are also con
`the transformer T7.
`The primary windings of the transformers T4 and T5
`nected in pairs to circuits similar to FIGURE 2 while
`for the sake of economy the amplifier A and phase sensi
`are each excited by a high frequency source (say 3000
`cycles per second). The primary winding of a transformer
`tive detector may be time shared between the circuits.
`FIGURE 3 is a circuit diagram of part of an alterna
`T8 is connected between a centre tap on the secondary
`tive display incorporating a touch-sensitive system. In
`winding of the transformer T4 and earth and the primary
`this display a matrix M1 of pairs of sensitive electrodes
`winding of a transformer T9 is connected between a cen
`Such as SP1 is arranged on the display. All the upper
`tre tap on the secondary winding of the transformer T5
`electrodes of each row are connected together to a posi
`and earth. The secondary windings of the transformers
`tive voltage source via a common resistor such as R11
`T8 and T9 are connected in series in a row interrogate
`and all the lower electrodes of each column are connected
`wire RI.
`together to earth via a common resistor such as R21.
`The primary windings of the transformers T6 and T7
`The terminals remote from the positive voltage source of
`are each earth centre tapped. The secondary winding of
`the resistors (such as R11) associated with the upper
`the transformer T6 is connected across the primary wind
`electrodes are connected to separate leads in a bundle
`ing of a transformer T10 and a switch SW1 is connected
`across them both. The secondary winding of the trans
`L1 and the terminals remote from earth of the resistors
`(such as R21) associated with the lower electrodes are
`former T7 is connected across the primary winding of a
`connected to separate leads in a bundle L2.
`transformer T11 and a switch SW2 is connected across
`When a pair of electrodes (such as the pair SP1) is
`them both. The secondary windings of the transformers
`touched by an operator a current will flow and this may
`T10 and T11 are connected in series in a column inter
`be detected both by a voltage drop at the terminal remote
`rogate wire CI.
`from the positive voltage source of the corresponding
`The acion of the circuit is an extension of that de
`resistor (such as R11) connected to the positive voltage
`scribed above with reference to FIGURE 2; the touching
`Source and a voltage rise at the terminal remote from
`of a pair of electrodes such as the pair SP12 will unbal
`earth of the corresponding resistor (such as R21) con
`ance two bridge circuits, namely in this case the bridge
`nected to earth. This rise and fall in voltage may be
`circuit which includes the secondary winding of the trans
`amplified, inverted and/or otherwise manipulated in a
`former T4 and the bridge circuit which includes the pri
`known manner and a series of known gates connected
`mary winding of the transformer T7, the bridge circuits
`between pairs of wires of which one is from the bundle
`associated with the columns (i.e. the bridge circuits which
`L1 and one from the bundle L2. By this way which pair
`include the primary windings of the transformers T6 and
`of wires has been touched may be determined exactly.
`T7 respectively) being energised from the transformers
`Alternatively the rows of upper electrodes and the
`T4 and T5 via the capacitances between the electrodes of
`columns of lower electrodes may be connected to inde
`the sensitive electrode paris SP00 etc. The particular
`pendent Systems each system being a set of circuits similar
`"row' and "column” bridges unbalanced and the direc
`to FIGURE 2, An output simultaneously from row and
`tion of unbalance define exactly which pair of electrodes
`column system then indicates which pair of electrodes
`is touched. The result will be an A.C. signal having a
`has been touched.
`given phase in the primary winding of one of the trans
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`Petitioner Exhibit 1022, Page 5
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`formers T8 or T9 and an A.C. signal having a given
`tor. These of course change quite often and normally con
`sist of up to seven alpha-numeric symbols. By labelling
`phase in the primary winding of one of the transformers
`T10 or T11. In a time-shared system which bridge is un
`"keys' in this way, communication with the system for a
`balanced may be determined by shorting out the primary
`particular aircraft can be established in a single operation.
`windings of the transformers T8 and T9 in turn and ob
`The first requirement of a data input device based on
`serving when the signal in the row interrogate wire RI
`the ideas outlined above, is a flexible display system, ca
`disappears and similarly shorting out the primary wind
`pable of presenting the possible choices to an operator.
`ings of the transformers T10 and T11 in turn and observ
`Such a possibility is clearly available in an electronic
`ing when the signal in the column interrogate wire CI
`data display for many applications. An extension to pro
`disappears.
`vide some form of graphical display may be desirable
`This system may obviously be extended to a larger
`in certain cases. The second requirement is to provide
`sensitive areas of the display screen which are capable of
`matrix of pairs of sensitive electrodes.
`FIGURE 5 is a diagrammatic representation of the
`producing a signal when touched by a bare finger. Such
`logic steps taken in a process using a data processing sys
`an arrangement is described above.
`.
`tem and input and output facilities.
`An example will be given of the use of the touch dis
`play device in the amendment of flight plans in an Air
`In such a process the system may be constantly reas
`Traffic Control system. In order to simplify the descrip
`sessing or revaluing a situation (step 1) in the light of
`tion it will be assumed that the amendments arise as a
`various data inputs. The result. of its reassessment or re
`result of radio telephone reports from the aircraft.
`valuation may be applied to the control of plant 3 (such as
`The sequence of events is as follows.
`industrial plant) or air traffic or some other situation.
`One data input to the system may be from sensors or
`Firstly, in the rest condition, i.e., between amendments
`other automatic devices some of which may be controlled
`the next action of the controller must logically be to refer
`by the plant 5. Another may be from other human opera
`to a particular aircraft, and the programme of the data
`tors 7. Sooner or later the data process will reach a stage
`processing system is written to take this into account. The
`in which the system is programmed to ask for human
`system already has the call signs of all the aircraft in
`intervention and a display of choices is made 9. The
`the sector, and it therefore displays these call signs one
`human operator makes the choice 11 in the light of past
`against each touch wire.
`experience 13 his senses (such as what he sees or hears)
`Secondly, when the aircraft calls and identifies itself
`15 and so on. The choice is indicated to the system 17
`by its call sign, the controller touches the wire against
`and becomes a further data input 19 and the process
`the call sign.
`continues.
`This may be contrasted with the conventional present
`It is obvious that the speed of such a process will de
`day action in which the five to seven characters involved
`pend upon the speed of the slowest step, that is, the step
`are typed on a teleprinter, or the number of the line on
`17 (in a conventional system) and the invention is an
`which the call sign is shown is read off and injected into
`attempt to overcome this speed limitation.
`an electronic data display.
`The first idea underlying the design and operation of
`The computer has now been instructed as to which
`a touch display is that, no matter what the overall and
`aircraft is involved and the computer programme is such
`complete range of possible signals from an operator might
`that the controller must next specify which item of the
`be, at any one time the signal actually sent by the opera
`flight plan is to be amended. The computer therefore
`tor to the data processing system will be one chosen
`displays on the top half of the touch-display the call
`from a strictly limited range. For example, the signal
`sign selected followed by the items of the flight plan,
`might be one of the ten numerical digits. Possibly one of
`each item consisting of its name and under the name the
`the widest range of choice actually exercised would be
`present value. Against the touch wires there are dis
`to select one from the twenty-six available alphabetic
`played the names of items, the pattern of the arrangement
`characters. Secondly, in order that the system should be
`of the items being made the same as in the flight plan dis
`able to interpret the signal correctly, it must know from
`played above.
`what range of possibilities it has been chosen and also
`The controller selects an item by touching the wire
`what consequences must stem from that choice. This in
`and the computer responds by marking the selected item
`formation within the system can therefore be used to
`and offering to the controller, against the touch wires,
`restrict the range of choice available to the operator at
`the list of possibilities for the first character of the value.
`any given time to just those possibilities which are rele
`If it is a numerical value the digits 0 to 9 may be offered
`vant to his present task. Subsequent to any input signal
`but if the first digit is limited, as for a time in minutes
`being received the system can alter the range of choice
`to 5 then only 0 to 5 need be offered; on the other
`as and when required. This control is, of course, exercised
`hand if the value is a symbol, then the appropriate sym
`by the computer programme in the system and in conse
`bols can be offered.
`quence, the operation of the touch display system can be
`The controller selects the character and the computer
`described as programmed control.
`inserts this in the flight plan under the first character of
`One consequence of this control is that the scope for
`the old value of the item and then, if the value consists
`operator errors, especially errors of omission, is signifi
`of more than one character, the computer presents the
`cantly reduced.
`possibilities for the next character and so on, until the new
`Since the matter actually displayed on the electronic
`value of the item has been built up and displayed under
`data display may be varied by the system, the meaning
`the old value.
`of the touch wires (or the units of whatever touch sys
`The computer than asks the controller by words against
`tem is in use) is variable. In other words, the display
`the touch wires is this new value to be "executed' or
`resembles an alpha-numeric keyboard in which the labels
`"ignored'; the controller inspects the old and new values
`attached to the keys are not fixed but can be changed by
`to see if the new value appears correct and credible and
`the system computers in accordance with the required
`if so, by touching "execute,” instructs the computer to in
`meaning at any time. The effect of this idea is far reach
`corporate the new value.
`ing. Not only does it allow the number of "keys' to be
`The computer then puts the display back to the initial
`very limited whilst retaining a large measure of flexibility
`in their interpretation but also it allows the "meaning' of
`reset condition to await the arrival of a new amendment.
`Various refinements can be added, for instance, “back
`a key to be changed as a result of information previously
`step” which cancels the previous input and restores the
`fed to the system. A particular example is given below
`display to the previous condition; this gives a quick way
`where one meaning attached to the keys is that of the
`of correcting input errors.
`“call signs” of the aircraft under control of a given opera
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`According to the amendment required, the sequence
`has been actuated by determining in which of said rows
`can vary. One in particular with deserves special mention
`and said columns said actuated contact means is located.
`is the sequence for cancelling a flight plan. It is of course,
`3. The apparatus defined in claim 1 wherein said
`means for generating visible images is a cathode ray
`very important that this does not happen by error and
`tube and said viewing means is a screen mounted on and
`so when the controller uses the touch wire labelled
`responsive to said cathode ray tube.
`“ERASE,” the computer is programmed to present the
`4. The apparatus defined in claim 1 wherein manual
`words “CONFIRM ERASURE OF KL104' for example.
`This illustrates the way in which the touch display can
`actuation of said touch sensitive contact means causes
`a capacitance change across the actuated contact means
`be used to alert the controller at critical phases in opera
`and said sensing means comprises a means for detecting
`tion.
`Of course other possible applications exist and if the
`a capacitance change at each of said touch sensitive
`display process has adequate flexibility to present solu
`tions to a problem pictorially then by appropriate labelling
`5. The apparatus defined in claim 4 wherein said means
`for detecting a capacitance change comprises a normally
`of the touch wires corresponding to the Solution the
`balanced alternating current bridge circuit adapted to
`choice can be indicated by a single operation. Again, an
`be unbalanced by a change in capacitance caused by
`other interesting possibility is the case of rarely used
`actuation of one of said touch sensitive contacts.
`procedures, for example. EMERGENCY. Here the in
`6. The apparatus defined in claim 1 wherein each of
`structions can be presented in plain language e.g., "alert
`said touch sensitive contact means incldue a first contact
`fire brigade,” “you must now choose to do. . . or to
`and a second contact and said sensing means comprises
`do
`..” and so on. The computer ensures that not
`means for detecting a resistance change between said
`only does the controller clearly understand what is to be
`first and second contacts of the selected contact means.
`done but ensures that no omissions occur.
`7. The apparatus defined in claim 6 wherein said means
`I claim:
`1. Apparatus for indicating to an output means which
`for detecting a resistance change between said first and
`portion of a data-representing image on a viewing means
`said second contacts of said selected contact means com
`prises normally balanced alternating current bridge means
`has been selected for further processing comprising
`display means including means for generating visible
`adapted to detect said resistance change.
`images, input means connected to said means for
`References Cited
`generating visible images for altering said image on
`said display means and viewing means responsive to
`UNITED STATES PATENTS
`said generating means for displaying said visible
`1,283,147 10/1918. Ghio.
`images,
`3,194,975
`7/1965 Diamond.
`a plurality of touch sensitive contact means sensitive
`3,207,905
`9/1965 Bray.
`to a change in impedance presented by touching by
`3,307,071
`2/1967 Diamond.
`the human body, said contact means being placed
`3,256,516
`6/1966 Melia et al. ------- 340-324.1
`adjacent said viewing means for indiacting which
`3,342,935
`9/1967 Leifer et al. ------- 340-324.1
`portion of the image on said viewing means has been
`8/1968 Ellis et al. --------- 340-324.1
`3,399,401
`selected, the position of said touch sensitive contact
`means selected with respect to said viewing means
`.
`. .
`'
`being related to the position of the selected portion
`of said image on said viewing means, and
`sensing means for determining and indicating to said
`output means which of said touch sensitive contacts
`has been activated.
`2. The apparatus defined in claim 1 wherein said plu
`rality of touch sensitive contact means are arranged in
`rows and columns and said sensing means is adapted to
`determine which of said touch sensitive contact means
`
`Bezgin, Generation of X and Y Coordinate Informa
`tion, IBM publication, vol. 1, No. 6, April 1959.
`JOHN W. CALDWELL, Primary Examiner
`MARSHALL M. CURTIS, Assistant Examiner
`U.S. C. X.R.
`235-61.6; 340-365
`
`20
`
`25
`
`30
`
`35
`
`40
`
`OTHER REFERENCES
`
`Petitioner Exhibit 1022, Page 7
`
`