(19) United States
`(12) Patent Application Publication (10) Pub. No.: US 2011/0175835 A1
` Wang (43) Pub. Date: Jul. 21, 2011
`
`
`
`US 20110175835A1
`
`(54) METHOD FOR SCANNING PROJECTIVE
`CAPACITIVE TOUCH PANEL, STORAGE
`MED] UM AND APPARATUS FOR SCANNING
`PROJECTIVE CAPACITIVE TOUCH PANEL
`.
`,
`W'anqiu Wang, Singapore ($6)
`
`Inventor:
`
`(75)
`
`.
`(73) Assrgnee:
`
`TPK TOUCH SOLUTIONS
`(XIAM EN) INC
`
`(21) App]. No.:
`
`13/009,847
`
`(22)
`
`Filed:
`
`Jan' 193 2011
`
`(30)
`
`Foreign Application Priority Data
`
`Jan. 21, 2010
`
`(CN) ......................... 2010101039566
`
`Publication Classification
`
`(51)
`
`Int Cl
`(2006.01)
`G015F 3/041
`(52) U.s.C1. ........................................................ 345/173
`(57)
`ABSTRACT
`
`The present invention relates to a method for scanning a
`projective capacitive touch panel including: A. scanning each
`first-axis electrode arranged along a first—axis and each sec-
`ond—axis electrode arranged along a second-axis, then obtain-
`ing the first-axis electrode and the second—axis electrode
`Whose self capacitance changes; B. detecting the mutual
`capacitance at each intersection between the first-axis elec-
`trode and the second-axis electrode whose sell" capacitance
`changes to determine whether
`the mutual capacrtance
`changes, then the area where the mutual capac1tance changes
`being taken as a touched area. The present invention also
`relates to a storage medium storing instructions of imple-
`menting above method and an apparatus that implements the
`above method.
`
`
`
`Petitioner Samsung EX-1043, 0001
`RESP_0003897
`
`Petitioner Samsung Ex-1043, 0001
`
`

`

`Patent Application Publication
`
`Jul. 21, 2011 Sheet 1 of6
`
`US 2011/0175835 A1
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`Petitioner Samsung EX-1043, 0002
`RESP 0003898
`
`Petitioner Samsung Ex-1043, 0002
`
`
`

`

`Patent Application Publication
`
`Jul. 21, 2011 Sheet 2 of 6
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`US 2011/0175835 A1
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`Petitioner Samsung EX-1043, 0003
`RESP_0003899
`
`Petitioner Samsung Ex-1043, 0003
`
`

`

`Patent Application Publication
`
`Jul. 21, 2011 Sheet 3 of 6
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`US 2011/0175835 A1
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`Petitioner Samsung EX-1043, 0004
`RESP_0003900
`
`Petitioner Samsung Ex-1043, 0004
`
`

`

`Patent Application Publication
`
`Jul. 21, 2011 Sheet 4 of 6
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`US 2011/0175835 A1
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`Petitioner Samsung EX-1043, 0005
`RESP_0003901
`
`Petitioner Samsung Ex-1043, 0005
`
`

`

`Patent Application Publication
`
`Jul. 21, 2011 Sheet 5 0f6
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`Petitioner Samsung EX-1043, 0006
`RESP 0003902
`
`Petitioner Samsung Ex-1043, 0006
`
`

`

`Patent Application Publication
`
`Jul. 21, 2011 Sheet 6 of6
`
`US 2011/0175835 A1
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`Petitioner Samsung EX-1043, 0007
`RESP 0003903
`
`Petitioner Samsung Ex-1043, 0007
`
`
`
`
`
`

`

`US 2011/0175835 A1
`
`Jul. 21, 2011
`
`METHOD FOR SCANNING PROJECTIVE
`CAPACITIVE TOUCH PANEL, STORAGE
`MEDIUM AND APPARATUS FOR SCANNING
`PROJECTIVE CAPACITIVE TOUCH PANEL
`
`BACKGROUND OF THE INVENTION
`
`[0001] This application claims the benefit of People’s
`Republic ofChinaApplication No. 2010101039566, filed on
`Jan. 21, 2010.
`
`FIELD OF THE INVENTION
`
`[0002] The present invention generally relates to a capaci-
`tive touch panel, and more particularly, to a method for scan—
`ning a projective capacitive touch panel, a storage medium
`and an apparatus for scanning a projective capacitive touch
`panel.
`
`DESCRIPTION OF THE RELATED ART
`
`[0003] Capacitive touch panels are divided into projective
`capacitive touch panels and surface capacitive touch panels
`The projective capacitive touch panel includes two layers of
`conductive electrodes orthogonally placed. One layer of con-
`ductive electrodes includes M (Mil) first-axis electrodes
`parallelly arranged along a first—axis (electrode X). The other
`layer of conductive electrodes includes N (N; 1) second-axis
`electrodes parallelly arranged along a second—axis (electrode
`Y).
`[0004] A conventional method to determine the position of
`the touch point is to scan all the M><N capacitances based on
`the fact that the position of the intersections in the electrode
`matrix can determine the position on the screen. As the size of
`the touch screen increases, a time period for scanning the
`electrode matrix becomes longer accordingly for the same
`scanning accuracy. For a 42—inch touch panel, if M is 170, N
`is 100 and the scanning time of each capacitance is 30 us, the
`time period for scanning the electrode matrix is 170><lOO><30
`us:0.51 s In other words, the seaming frequency is l/0.5 l :1 .
`96 Hz. That is a very low scanning frequency, which will
`cause a delay in determining a touch point. If the touch panel
`is a multi-touch panel then the time delay will get worse
`leading to a loss of touch points.
`[0005] Thus, it is desired to provide a method for scanning
`a projective capacitive touch panel that overcomes the above
`drawbacks of the conventional scanning method.
`
`SUMMARY OF THE INVENTION
`
`In one aspect, a method for scanning a projective
`[0006]
`capacitive touch panel is provided including: A. scanning
`each first-axis electrode arranged along a first—axis and each
`second—axis electrode arranged along a second—axis,
`then
`obtaining the first—axis electrode and the second—axis elec-
`trode whose self capacitance changes; B. detecting the mutual
`capacitance at each intersection between the first-axis elec-
`trode and the second-axis electrode which electrodes’ self
`
`capacitance changes to determine whether the mutual capaci-
`tance changes, then taking an area where the mutual capaci—
`tance changes as a touched area. Also provided are storage
`medium for storing instructions of implementing the above—
`described method and an apparatus that
`implements the
`above-described method.
`
`[0007] Thus, by combining detecting self capacitance and
`mutual capacitance, the method of present invention can sig-
`
`nificantly reduce the scanning time and boost the scanning
`frequency while the scanning accuracy is also guaranteed in a
`large touch panel.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`Skilled persons in the art will understand that the
`[0008]
`drawings, described below, are for illustration purposes only
`and do not limit the scope of the present invention in any way.
`It is appreciated that the quantity ofthe disclosed components
`could be more or less than what is disclosed unless expressly
`specified otherwise.
`[0009]
`FIG. 1 shows a projective capacitive touch panel
`connecting to a controller according to the present invention;
`[0010]
`FIG. 2 illustrates scanning the self capacitance of
`first-axis electrodes along a first-axis according to the present
`invention;
`[0011]
`FIG. 3 illustrates scanning the self capacitance of
`second-axis electrodes along a second-axis according to the
`present invention;
`[0012]
`FIG. 4 shows a single touch on a touch panel accord—
`ing to a first embodiment of the present invention;
`[0013]
`FIG. 5 is a plan view of a single touch on a touch
`panel according to a preferred embodiment of the present
`invention;
`[0014]
`FIG. 6 shows a double touch on a touch panel
`according to the first embodiment of the present invention;
`FIG. 7 shows a view of one ofthe electrodes in FIG.
`[0015]
`6;
`[0016]
`6.
`
`FIG. 8 shows the touched area and ghost area in FIG.
`
`DETAILED DESCRIPTION OF THE INVENTION
`
`In accordance with the usual meaning of “a” and
`[0017]
`“the” in patents, reference, for example, to “an” electrode or
`“the” electrode is inclusive of one or more electrodes. In this
`
`application, the use of the singular includes the plural and
`vice versa unless specifically stated otherwise, for example,
`the term “mutual capacitance” includes singular and plural
`forms,. The section headings used herein are for organiza-
`tional purposes only, and are not to be construed as limiting
`the subject matter described.
`[0018] The detailed description of the present invention
`will be discussed in the following embodiments, which are
`not intended to limit the scope of the present invention, but
`still can be adapted for other applications. While drawings are
`illustrated in details, it is appreciated that the quantity of the
`disclosed components could be greater or less than disclosed,
`except those components with express restricting amount.
`[0019] The method ofthe present invention is performed by
`a touch screen including a projective capacitive touch panel
`13 and a controller 14, which is shown in FIG. 1, the control—
`ler 14 is electrically connected to the projective capacitive
`touch panel 13 to drive the projective capacitive touch panel
`13. The projective capacitive touch panel 13 includes M first—
`axis electrodes parallelly arranged along a first-axis (defined
`as x-axis) and N second-axis electrodes parallelly arranged
`along a second—axis (defined as y—axis). The first-axis and the
`second—axis are orthogonal to each other. There are M+N self
`capacitances measured as relative to ground. There are also
`M><N mutual capacitance formed at intersections between the
`first-axis electrodes and the second—axis electrodes.
`
`Petitioner Samsung Ex-1043, 0008
`RESP_0003904
`
`Petitioner Samsung Ex-1043, 0008
`
`

`

`US 2011/0175835 A1
`
`Jul. 21, 2011
`
`[0020] The method for scanning a projective capacitive
`touch panel includes the following steps:
`A. scanning each first-axis electrode and each second-axis
`electrode to get the first—axis electrodes and the second—axis
`electrodes whose selfcapacitance change;
`B. detecting the mutual capacitance at each intersection
`between the first—axis electrode and the second-axis electrode
`
`which electrodes’ self capacitance changes to determine
`whether the mutual capacitance changes, then the area where
`the mutual capacitance changes being taken as a touched area.
`[0021]
`FIG. 4 shows a single touch on a touch panel accord—
`ing to a first embodiment of the present invention. A single
`touch affects the first—axis electrode(s) and the second—axis
`electrode(s) that pass through the touched area 133. In some
`embodiments, the width of the first-axis electrode or the
`second-axis electrode may be wider than the touched area
`133, thus the single touch may only involves one first—axis
`electrode and one second—axis electrode. Ifchanges ofthe self
`capacitance of the first—axis electrode and second-axis elec-
`trode are detected in the case of the single touch according to
`step A mentioned above, the position of a touch point can be
`determined by obtaining the x-coordinate (Xi, léiéM) of
`the first-axis electrode and the y-coordinate (Yj, léj EN) of
`the second—axis electrode. The mutual capacitance at the
`intersection between the first-axis electrode and the second—
`
`aXis electrode is further detected to confirm the position ofthe
`touched area which has only one touch point.
`[0022]
`In other embodiments, the touched area is generally
`wider than the width ofthe electrodes. FIG. 5 is a plan View of
`a single touch on a touch panel according to another embodi-
`ment of the present invention, the width of the electrodes is
`halfof the touched area 134, thus the touched area 134 of the
`single touch affects two first—axis electrodes and two second-
`axis electrodes that pass through the touched area 134. There
`are four intersections having different coordinates located in
`the touched area, and a centroid can be further calculated
`according to the coordinates ofthe four intersections. Assum-
`ing that the x-coordinates ofthe touch-relevant first-axis elec-
`trodes are X,, X,“ (1 éiéM—l), the voltage difference of the
`touched first—axis electrodes are U,, Ui+1(1‘=:i‘=’~M—l) respec—
`tively; the y-coordinates of the touch—relevant second—axis
`electrodes areYl.,Y,.+1(1§i§N—1), and the voltage difference
`of the touched second-axis electrodes are U], Uj+1(1 éj EN—
`1) respectively. The X-coordinates of the centroid is X:(X,><
`Ui+Xi+l><Ui+1)/’(U,+U,+l), and the y-coordinates of the cen-
`troid isY:(Yj><Uj+Y1+ 1 ><Uj+1)/(Uj+Uj+1), then the position of
`the touch point is determined by the centroid (X,Y). In other
`embodiments, the single touch may involves more than two
`first-axis electrodes or two second-axis electrodes, and the
`calculation method of the centroid is similar to the above
`mentioned method.
`
`[0023] A more complicated situation is that there may be
`more than one touched area. A touch with more than one
`
`touched area will lead to forming ghost areas which are not
`really touched, but just a theoretically calculated result. If the
`ghost areas are not eliminated, they will be regarded as real
`touched areas in subsequent process, definitely causing fake
`locating. FIG. 6 shows a double touch on a touch panel
`according to another embodiment of the present invention.
`The touch-relevant first—axis electrodes and second—axis elec-
`
`trodes form intersections grouped in four areas 135a, 1352),
`1350 and 135d (as shown in FIG. 7), ofwhich areas 135a and
`13519 are touched areas and areas 135(: and 135d are ghost
`areas (as shown in FIG. 8). Since the ghost areas can not be
`
`recognized only by determining changes of the self capaci-
`tance of the first-axis electrodes and the second—axis elec-
`
`trodes, the mutual capacitance at the intersections in the areas
`135a, 135b, 135c and 135d will be further detected to deter-
`mine the touched areas 135a and 1351) according to step B.
`And the touch points are determined by calculating the cen-
`troid of the touched areas.
`
`[0024] According to the above embodiments, it needs to
`scan M+N+(p1xp2) times comparing to the conventional M
`X N times to get a touched area in a period of scanning,
`wherein M and N are the number of the first-axis electrodes
`
`and the second-axis electrodes respectively, pl and p2 are the
`number ofthe touch-relevant first-axis electrodes and second-
`
`axis electrodes. When M and N are significantly greater than
`2 and pl, p2 are very small, M><N is significantly greater than
`M+N+(p1xp2). In the case of a touch that two first-axis elec—
`trodes and two second-axis electrodes are involved, if M and
`N are both greater than 4, M><N will be greater than M+N30
`2x2. In addition, if a touch involves 10 first-axis electrodes
`and 10 second-axis electrodes (this number is generally the
`maximum number of a multi-touch system can support), M
`and N are both much greater than 11 in most touch panel
`applications, thus M><N will be much greater than M+N+10><
`10.
`
`[0025] The calculation for a 42-inch touch screen which
`has 170 first—axis electrodes and 100 second—axis electrodes is
`
`described in detail as follows: referring to FIG. 4, in the case
`of a single touch, only one first—axis electrode and one sec-
`ond—axis electrode are touched, scanning the 170 first-axis
`electrodes and 100 second-axis electrodes will immediately
`get the first-axis electrodes and second-axis electrodes whose
`self capacitance changes, and get the unique intersection 133,
`thus conclude the touch point. Each scanning costs about 30
`us, therefore the total scanning time in a scam1ing period is
`(170+100)><30 us+l><l><30 us:8.13 ms, that is, the scanning
`frequency is 123 frames per second, which is greater than the
`conventional 1.96 frames per second. Referring to FIG. 6, in
`the case of a double touch and each touch with only one
`first-axis electrode and one second-axis electrode being
`touched, two first-axis electrodes (131a, 1311)) and two sec-
`ond—axis electrodes (132a, 1322)) will be detected. The
`mutual capacitance at the four intersections will be detected
`according to step B, so the total scanning time in a scanning
`period is (170+100)+30 tts+2><2><30 its:8.22 ms, that is, the
`scanning frequency is 121 frames per second, which is also
`greater than the conventional 196 frames per second.
`[0026]
`It is obvious that the method for scam1ing a projec-
`tive capacitive touch panel of the present invention can sig-
`nificantly reduce the scanning time and boost the scanning
`frequency while the scamiing accuracy is also guaranteed for
`a large touch panel.
`[0027] The process of obtaining the first—axis electrode and
`the second—axis electrode whose self capacitance changes
`according to step A includes more detailed steps as follows:
`comparing a current self capacitance of each first-axis elec-
`trode and second—axis electrode with a preset reference self
`capacitance;
`obtaining the first—axis electrode and the second-axis elec—
`trode whose current self capacitance satisfies a preset condi—
`tion defined by a preset threshold value to be exceeded by the
`difference of the self capacitance to the preset reference self
`capacitance.
`[0028]
`Self capacitance can be obtained by charging an
`electrode (first-axis electrode or second-axis electrode) to a
`
`Petitioner Samsung EX-1043, 0009
`RESP_0003905
`
`Petitioner Samsung Ex-1043, 0009
`
`

`

`US 2011/0175835 A1
`
`Jul. 21, 2011
`
`preset capacitance and then comiecting a reference capacitor
`to the electrode to charge the reference capacitor, the elec-
`trode will discharge and its voltage will decrease. The time
`that the voltage decreases to a preset voltage value can be
`measured and used to represent the self capacitance of the
`electrode.
`
`[0029] There are two ways of setting the preset reference
`selfcapacitance of each first—axis electrode and second-axis
`electrode: the first way is directly writing the empirical value
`in the controller 14; the second way is getting an average
`value of multiple initial self capacitance correspondingly
`obtained from initialization scanning of the first-axis elec-
`trode and second-axis electrode repeatedly Since each elec-
`trode has a preset reference self capacitance, there will be
`M+N preset reference self capacitance.
`[0030] The initialization scanning includes: charging each
`of the first-axis electrode and second-axis electrode; dis-
`charging the reference capacitor connected to each of the
`first—axis electrode and second—axis electrode; obtaining the
`initial self capacitance of each of the first—axis electrode and
`the second—axis electrode according to the time of discharg—
`ing when the discharging process is completed.
`[0031]
`FIG. 2 illustrates scanning the self capacitance of
`first-axis electrodes along a first—axis according to the present
`invention. The controller 14 charges each first—axis electrode
`arranged along the first-axis (X-axis) and then discharge each
`of the first-axis electrode to the reference capacitor corre-
`spondingly connected to each of the first-axis electrode.
`When the discharging process of the first-axis electrode is
`completed, the current selfcapacitance of the first—axis elec—
`trode can be calculated. FIG. 3 illustrates scanning the self
`capacitance of second—axis electrodes along a second—axis
`according to the present invention. The current self capaci-
`tance of the second-axis electrode can be obtained by the
`same method.
`
`[0032] The process of determining whether the mutual
`capacitance changes includes: comparing a current mutual
`capacitance at each intersection with a preset reference
`mutual capacitance at the intersection; obtaining the current
`mutual capacitance that satisfies a preset condition.
`[0033] There are also two ways of setting the reference
`mutual capacitance at the intersections:
`the first way is
`directly writing the empirical value in the controller 14; the
`second way is calculating an average value of multiple initial
`mutual capacitance obtained from initialization scanning of
`the intersections repeatedly. Since there is a reference mutual
`capacitance for each intersection, there will be M><N preset
`reference mutual capacitance totally.
`[0034] The initialization scamring includes: charging each
`second-axis electrode; collecting the electric charges induced
`in the first—axis electrode and converting the electric charges
`to voltage value, according to which obtain the initial mutual
`capacitance at each intersection. In an alternative embodi-
`ment, the first—axis electrode may be firstly charged.
`[0035] The self capacitance or mutual capacitance may
`change in many situations, not only by touch, but also such as
`insufficient charge of the electrodes. In order to distinguish
`the capacitance change caused by a real touch or other events,
`the change of the current self capacitance or the current
`mutual capacitance should satisfy a preset condition. Gener-
`ally, the preset condition is defined by a preset threshold
`value. For detecting the self capacitance, the difference ofthe
`self capacitance to the preset reference self capacitance must
`be greater than a corresponding preset threshold value, when
`
`this condition is satisfied, a touch on the electrode can be
`confirmed. Similarly, for detecting the mutual capacitance
`change, the difference of the current mutual capacitance to
`the reference mutual capacitance at an intersection must be
`greater than another corresponding preset threshold value,
`when this condition is satisfied, a touch on the intersection
`can be confirmed.
`
`[0036] A storage medium is provided as well. The storage
`medium is used for storing a set of instructions capable of
`being executed by a processor to perform a method for scan—
`ning a projective capacitive touch panel. The method com—
`prises:
`A. scanning each first-axis electrode arranged along a first-
`axis and each second-axis electrode arranged along a second-
`axis, then obtaining the first-axis electrode and the second-
`axis electrode whose selfcapacitance changes;
`B. detecting the mutual capacitance at each intersection
`between the first—axis electrode and the second-axis electrode
`
`whose self capacitance changes to determine whether the
`mutual capacitance changes, then taking an area where the
`mutual capacitance changes as a touched area.
`[0037] A system for scanning a projective capacitive touch
`panel is also provided. The system includes a scanning mod—
`ule and a controlling module. The scamiing module is used
`for detecting self capacitances of first-axis electrodes and
`second—axis electrodes. The controlling module is used for
`determining whether the self capacitances change and con—
`trolling the scanning module to detecting a mutual capaci-
`tance at an intersection between a first-axis electrode and a
`
`second—axis electrode if the self capacitance of the first-axis
`electrode and the second—axis electrode changes and deter-
`mining a touched area defined by the intersection having a
`changed mutual capacitance.
`[0038] While certain embodiments have been shown and
`described, various modifications and substitutions may be
`made thereto without departing from the spirit and scope of
`the invention. Accordingly, it is to be understood that the
`present invention has been described by way of illustration
`and not limitations.
`
`What is claimed is:
`
`1. A method for scanning a projective capacitive touch
`panel, comprising:
`A- scanning each first—axis electrode arranged along a first-
`aXis and each second—axis electrode arranged along a
`second—axis by a controller, then obtaining the first-axis
`electrode and the second-axis electrode whose self
`
`capacitance changes;
`B— detecting mutual capacitance at each intersection
`between the first-axis electrode and the second-axis
`
`electrode which electrodes’ self capacitance changes to
`determine whether the mutual capacitance changes, then
`area where the mutual capacitance changes being taken
`as a touched area.
`
`2. The method according to claim 1, wherein the process of
`obtaining the first-axis electrode and the second-axis elec-
`trode whose self capacitance changes according to step A
`comprises:
`comparing a current self capacitance of each of the first-
`aXis electrode and the second—axis electrode with a pre-
`set reference self capacitance of the respective first-axis
`electrode and second-axis electrode;
`obtaining the first—axis electrode and the second—axis elec-
`trode whose current self capacitance satisfies a preset
`condition.
`
`Petitioner Samsung EX-1043 , 0010
`RESP_0003906
`
`Petitioner Samsung Ex-1043, 0010
`
`

`

`US 2011/0175835 A1
`
`Jul. 21, 2011
`
`3. The method according to claim 2, wherein the process of
`obtaining the current self capacitance comprises:
`charging each of the first—axis electrode and the second-
`aXis electrode;
`discharging each of the first—axis electrode and the second-
`axis electrode to a reference capacitor correspondingly
`connected to the first-axis electrode and the second-axis
`electrode;
`obtaining the current self capacitance ofthe first-axis elec—
`trode and the second-axis electrode when the process of
`discharging is completed.
`4. The method according to claim 2, wherein the preset
`reference self capacitance of each of the first-axis electrode
`and the second-axis electrode is an average value of multiple
`initial self capacitance obtained from repeated initialization
`scanning of each of the first—axis electrode and the second-
`axis electrode correspondingly.
`5. The method according to claim 4, wherein the initializa-
`tion scanning comprises:
`charging each of the first—axis electrode and the second-
`axis electrode;
`discharging each of the first-axis electrode and the second-
`axis electrode to a reference capacitor correspondingly
`connected to each of the first—axis electrode and the
`second—axis electrode;
`obtaining the initial self capacitance of each of the first—
`axis electrode and the second—axis electrode when the
`
`process of discharging is completed.
`6. The method according to claim 2, wherein the preset
`condition is difference of the self capacitance to the preset
`reference self capacitance is greater than a preset threshold
`value.
`
`7. The method according to claim 1, wherein the process of
`determining whether the mutual capacitance changes com-
`prises:
`comparing a current mutual capacitance at each intersec-
`tion with a preset reference mutual capacitance at the
`intersection;
`obtaining the area where the current mutual capacitance
`satisfies a preset condition.
`8. The method according to claim 7, wherein the process of
`obtaining the current mutual capacitance comprises:
`charging each of the second-axis electrode whose self
`capacitance changes;
`collecting electric charges induced in the first—axis elec-
`trode and converting the electric charges to voltage
`value, according to which obtaining the current mutual
`capacitance at the intersection.
`
`9. The method according to claim 7, wherein the preset
`reference mutual capacitance at the intersection is an average
`value of multiple initial mutual capacitance obtained from
`initialization scanning of the intersection repeatedly.
`10. The method according to claim 9, wherein the initial-
`ization scamiing comprises:
`charging each of the second-axis electrode;
`collecting electric charges induced in the first-axis elec-
`trode and converting the electric charges to voltage
`value, according to which obtaining the initial mutual
`capacitance at the intersection.
`11. The method according to claim 7, wherein the preset
`condition is difference of the current mutual capacitance to
`the preset reference mutual capacitance at the intersection is
`greater than a preset threshold value.
`12. The method according to claim 1 further comprising:
`calculating centroid of the touched area.
`13. The method according to claim 1, wherein if the self
`capacitance of any of the first—axis electrode or the second-
`axis electrode does not change, repeat step A.
`14. A storage medium for storing a set of instructions to
`perform a method for scanning a projective capacitive touch
`panel, the method comprising:
`A— scanning each first—axis electrode arranged along a first—
`axis and each second-axis electrode arranged along a
`second—axis, then obtaining the first-axis electrode and
`the second-axis electrode whose self capacitance
`changes;
`13- detecting mutual capacitance at each intersection
`between the first-axis electrode and the second-axis
`
`electrode whose self capacitance changes to determine
`whether the mutual capacitance changes,
`then area
`where the mutual capacitance changes being taken as a
`touched area.
`
`15. A system for scanning a projective capacitive touch
`panel, comprising:
`a scanning module for detecting self capacitances of first-
`aXis electrodes and second—axis electrodes;
`a controlling module for detemiining whether the self
`capacitances change and controlling the scanning mod-
`ule to detect a mutual capacitance at an intersection
`between the first-axis electrode and the second-axis
`
`electrode if the self capacitance of the first—axis elec-
`trode and the second-axis electrode changes and deter-
`mining a touched area defined by the intersection having
`a changed mutual capacitance.
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`
`Petitioner Samsung Ex-1043, 0011
`RESP_0003907
`
`Petitioner Samsung Ex-1043, 0011
`
`