TW200817987A - Contact sensitive device and method of determining information relating to a contact thereon - Google Patents

Abstract

A contact sensitive device comprises a member (12) capable of supporting bending waves, three sensors (16) mounted on the member (12) for measuring bending wave vibration in the member, whereby each sensor (16) determines a measured bending wave signal and a processor which calculates a location of a contact on the member from the measured bending wave signals. The processor calculates a phase angle for each measured bending wave signal and a phase difference between the phase angles of least two pairs of sensors so that at least two phase differences are calculated from which the location of the contact is determined.

Description

200817987 IX. Description of the invention: [Technical field to which the invention pertains] The present invention relates to a touch sensitive device. [Prior Art] A visual display typically contains some form of touch sensitive screen. This phenomenon has become increasingly common with the advent of next-generation portable multimedia devices such as handheld computers. The most sophisticated technique for detecting contact using waves is the Surface Acoustic Wave (SAW) technique, which produces high-frequency waves on the surface of a glass' screen and uses high-frequency wave attenuation caused by finger contact to detect the touch. Control position. This technique is a "time-of-flight" type in which the time required for the arrival of the disturbance - or multiple sensors - is used to make the contact position. This method is feasible when the medium acts in a non-dispersive manner, ie the speed of the wave does not vary significantly over the relevant frequency range. In the inventors' WO01/48684 and PCT/GB2002/003073, two types of touch sensitive devices and methods of use thereof have been proposed. In the two applications, the apparatus can include a component capable of supporting bending wave vibrations and a component mounted thereon for measuring bending wave vibrations in the component and for transmitting a signal to the processor A sensor in which a contact made from a surface of the component produces a bending wave vibration change in the component to calculate information about the contact. / Curved wave vibration means an excitation, such as by contact, which causes an out-of-plane displacement of the offending component. Many materials bend, some have a pure curvature with a completely square root dispersion relationship, and some have a blend of pure bow and chopped test. The dispersion relationship indicates the in-plane velocity of the wave. 127365.doc 200817987 The dependence of the degree on the frequency of the wave. Words have advantages such as improved strength and reduced sensitivity to surface scratches. However, the bending wave is a scatter wave, that is, the speed of the bending wave and thus the pulsation time is related to the frequency. In general, a pulse contains a wide range of frequency components, so if the pulse travels a short distance, the high frequency component will arrive first. In WO 01/48684 and PCT/GB2002/003073, the correction of the measured bending wave signal into a propagating signal from a non-dispersive wave source can be applied so that the technique used in the radar and sonar fields can be applied to detect the contact position. . SUMMARY OF THE INVENTION According to one aspect of the invention, a touch sensitive device is provided, the device comprising a component capable of supporting a bending wave, and three sensors mounted on the component for measuring bending wave vibrations in the component Wherein each sensor determines a measured bending wave signal and a processor for calculating a position of a contact on the component from the measured bending wave signal, the touch sensitive device being characterized by the processing A phase angle is calculated for each of the measured bending wave signals, and then a phase difference between the phase angles of at least two pairs of sensors is calculated and the position of the contact is determined from the phase difference. According to a second aspect of the present invention, there is provided a method of determining information relating to a contact on a touch sensitive device, the method comprising the steps of: providing a component capable of supporting a bending wave and mounting on the component for measurement Three sensors for bending wave vibrations in the component; applying a contact at a location of the component; using each sensor to determine a measured bending wave signal and calculating from the measured bending wave signal a contact 127365.doc 200817987, the method is characterized by calculating a phase angle of each measured bending wave signal, calculating a phase difference between phase angles of at least two pairs of sensors, and from at least two The calculated phase difference determines the location of the contact. The following features may be adapted to the processor 4 and the m-pad to adapt the processor to provide a number of calculations or processing steps of the method. The reflected wave can be suppressed by placing the absorber in contact with the edge of the component. The mechanical impedance of the absorption n and the material can be selected to minimize bending wave reflection at the edge of the element. In particular, the impedance chosen is such that the bending wave energy is similar to the selected frequency. The frequency band is strongly absorbed. The impedance of the absorber can be selected to be both resistant and compatible. The impedances can be selected to satisfy the following equation: where ΖΤ is the termination impedance of absorption ’ and ~ is the mechanical impedance of the edge of the component. The absorption II can be made of a blistering plastic which can have an open or closed cell and can be a polyanthene or a live animal 7#~久文四曰忒祆虱 ethylene. For example, the foam can be a soft, closed cell-based bead, such as MIERSTM, or a medium to high density open cell vinegar foam. Another suitable foam that has been found is an acrylic closed cell bubble bed. These have a higher degree of damping and a higher hardness. Such properties are particularly suitable for edge termination of hard, heavy materials such as glass. Examples include the 3M serial number he, side, 495〇 and 4655. The absorber can extend substantially around the perimeter of the component. The absorber can be used as a mounting frame for supporting the component in the frame or to the other surface. The surface of the component can include a raised pattern such that a contact dragged across the surface provides a variable force to the component to create a bowing wave in the component. The pattern can be a periodic or quasi-periodic pattern having a statistically well defined spatial fluctuation distribution. The pattern can be a random pattern such that the contact traveling over the surface of the component produces a random bending wave signal.

The Ik machine embossed pattern can be an anti-reflective coating, an anti-glare surface light or a pattern of light found on many well-known transparent panels placed in front of the electronic display. Can be by having a selected frequency (7). A bandpass filter and a waver centered and having a bandwidth Δω are used to process each of the measured bending wave signals. The bandwidth of the filter is preferably chosen to solve the Doppler effect, where the frequency at which a bending wave reaches a point is different from its original frequency. Therefore, the bandwidth preferably satisfies the following relationship: Δω»2^〇)ν_ Where vmax is the maximum lateral velocity of contact across the surface, for example, if the contact is provided by a stylus, Vmax is the maximum speed at which the user can move the stylus. Obtained by comparison with a reference signal. The reference signal may have a frequency %. The average phase difference between the measured phase input and the reference apostrophe is preferably measured during interval 2. Alternatively, the reference signal may be from a second A filtered signal is derived from one of the sensors, in which case the measured phase is the difference between the two input signals. 曰 The phase difference can be calculated at intervals of 2 W-, which can be less than 10 ms. Interval. Reference and input signal feedback, < - phase detection 127365.doc 200817987. The output of the phase detector can be fed through a low pass with a cutoff frequency of about / 2 The waver, then through the digitizer, and finally through a processor to calculate the phase angle Θ. The instantaneous phases θι(1) and &(1) of the two measured bending wave signals satisfy the phase difference equation: =k(ty〇)Axlm + 2^nIm 〇

U where ΔΧΐTM=Χΐ-^, Um and X, respectively, from the contact position to the distance between each sensor marked with a paw and a ), and k(6)) is a wave vector. If the path length difference between the two sensors is less than the coherence length of the belt moneyer, the equation can be satisfied. The coherence length of the bandpass filter can be defined as: , 2 feet 0 △ cok (co0) coherent The condition is therefore ^^. If the coherent condition is not met, the above phase equation may not be satisfied. Prison this

The value of the difference between the phase and the phase angle determines the position of the contact.形状 The shape of the part can be chosen to limit the amplitude of < to less than - the wavelength of the L::: ). In this case, if all possible values of ~ satisfy the condition, there is a ^ value to infer. ~ "The person, η can be estimated in some way or., the range of b values can be used to produce a collinear path long sounds s ^ ^ show the king only my degree difference, thus the discrete hyperbolic winding in the column, 丨v main _ face on the line of a line to the table of the impossible contact. ^τ #丄 The path length difference is pinned. You can hunt each hyperbolic parent or nearly intersecting _$+, the inner hyperbolic phase 4", and the position of the contact position 。, which is defined by the difference in length. This point may be true 127365. Doc -10- 200817987 Contact position. If I is unknown' then the minimum number of hyperbola series required to determine the contact position is one and the likelihood of correct contact is increased by increasing the number of hyperbola to be drawn. A plurality of sensors are used, wherein a phase angle difference can be calculated for each pair of sensors to produce a plurality of hyperbola. In this particular embodiment, the minimum number of sensors is three. Ο u or if ^ Unknown 'The measured bending wave signal from each sensor can be divided into two or more discrete frequency bands, where each phase band and = each pair of sensing 11 can be calculated - the phase angle difference. Calculating multiple phase angle differences # ' for the sensor but the phase angle differences at different frequencies are derived from the same path length difference. Therefore, the minimum number of sensors is three. It can be at least with different passband frequencies Two band pass filters The device processes the bending wave signal, thereby dividing the frequency band. For example, using two bandpass filters having frequency and two, the phase angle difference ΔA 'A0b of the two sensors can be defined as A0a==kK+^,) Ax + 2^na A0b=:kK-^)Ax + 2^nb where ΔΧ is the single path length difference defined by the contact and sensor position. Therefore 'can select the value of na and call' to make the measured phase angle The difference can be inferred from the similar value of the path length difference. Only one (na, called) value combination satisfies this point. In this case, the true value of the path length difference can be determined. The correct 'matching (na, nb) can be To minimize the following expression: △0a -2 3 A0h -2mb Η^ο〇+ωδ) k(〇)0-^) 127365.doc -11 - 200817987 Path length difference can be estimated as

ΔX A0a ~2^na A0b -2mh ]<ί(ω0+ωδ) k(ty〇-ωδ) If this procedure is repeated for two pairs of sensors, the difference between the two path lengths can be determined, the two The difference in path length can in turn be used to determine the location of the contact. Alternatively, if 'unknown', the initial decision of the contact location can be made using the method taught in w〇01/48684 and PCT/GB2002/003073 (as outlined in Figure i i). Then, it can be assumed that the contact is 1* more than the bending wave shift 因此 因此 so the phase angle difference varies less during the time scale. Therefore, each value of η can be selected to minimize variations in path length differences. The measured phase angle difference can include a random error that would result in the selection of an incorrect η value. For example, the state space estimator can be used to mitigate the possibility of a continuous sequence of n by means of a state-of-the-art estimator such as the well-known evaluator. The sequence with the largest possible measurement is selected. The state space estimator provides an estimate of the state of the system in which the noise is measured. The necessary input of the state space estimator is system-like: it: i statistical description. An example of this state is a set of coordinates that illustrate the position and velocity of the component. A well-known system, one: Preface two other state space estimators can provide the observed noise measurements. The second column: The measurement of the likelihood that the model of the state is consistent. The t^ state space estimator can therefore be used to take a pair of path length differences made at different times (eg ^ 2 ' 3 , ···), and the sequence of the cool A 2 兴 A2 is used to estimate the system state of the time. That is, contact, and can be down to the speed of the e-sports. The equivalent of the 127365.doc path length difference is related to the system model, which is the total -12-200817987. If the phase length difference sequence is obtained from a phase angle difference sequence and _, a group integer (^(1)), n(t2), n(t3), . . . , the matrix is generated by the state space estimator. The measured value of the possibility can be used to infer the possibility that the correct value has been selected. From this, it is concluded that the method used to select the correct sequence of the integer η is to find the sequence that the state space estimator gives to the most daunting probability measurement.

As mentioned above, the state space estimator uses some statistical description of the evolution of the system state. The appropriate model for contact movement can be - a simple random walk. Or the model can use a detailed description of how the user moves the stylus or finger. - The example is a statistical description of how the user moves a pen while writing a person's text or individual characters. The processor can be adapted to include any information available about the intended location of the contact in the garment. For example, 'If the component is a graphical user interface input device' where the user can choose to press a "button", then a useful system assumes that any contact on the component occurs in a discrete area corresponding to the button. Alternatively, a map of the probability of contact may occur, and the probability is based on the expected behavior of the user. The device can include a software application having a graphical user interface (GUI) that utilizes an application interface (Αρι) to interact with the operating system, wherein the API tuning is adapted to generate a probability map. The probability map can be based on the position, size, and frequency of use of the object presented by the graphical user interface. The probability map can also be based on information about the relative possibilities of launching various Gm components. 127365.doc -13 - 200817987 The following features are applicable to all specific embodiments of the invention. The apparatus can include a recording member for recording a measured f-wave wave from the sensor or each sensor over time as the contact moves across the component; Calculate information related to contact. The two devices may be spaced at or near the edge of the component. It can be used to convert the f-curve vibration into a class. A's Sensing Converter This part can be in the form of a plate or panel. The component can be transparent or =' for example having a printed pattern. The part can have a uniform thickness. Or = the component may have a more complex shape, such as a curved surface and/or the device may be a pure passive sensor, wherein the bending wave is generated by an initial impact or frictional movement of the contact: a bending wave signal. The contact can be touched by a finger or a stylus (which can be in the form of a hand-held pen). The touch can be generated - even the stylus is The movement of the LrT signal on the component is affected by the speed of the stylus on the component. The stylus can be, for example, a rubber tip that is "difficult to create a f-curve in the component to apply a variable force to the surface m. the variable force can be adhered to the component.表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面 表面The surface slides 71σ leather k to allow internal frequency components. "The wave can have an ultrasonic region (10) kHZ) 127365.doc -14· 200817987 The component can also be a "acoustic ejector" and can be mounted on the transmitter 'on the part' to excite bending wave vibrations in the part to produce an acoustic output. The frequency band of the audio signal of the converter is preferably different and does not overlap the frequency band of the measurement of the sensor. The audio signal can thus be filtered, such as: the 'audio frequency band can be limited to frequencies below 2G kHz, and the vibration measurement can be limited to frequencies above 20 kHz. A timer can have dual functionality and acts as a transmit converter.

The or each transmit transducer or sensor can be a bend converter that is directly soldered to the component, such as a piezoelectric transducer. Alternatively, the or each transmit transducer or sensor can be an inertial conversion coupled to the component at a single point. The inertial converter can be a motorized converter or a piezoelectric converter. The touch sensitive device in accordance with the present invention can be included in a mobile phone, laptop or personal data assistant. For example, a keypad that is conventionally mounted to a mobile phone can be replaced by a continuous mold that is a touch sensitive device in accordance with the present invention. In a laptop, a touchpad functioning as a mouse controller can be replaced by a continuous mold which is a touch sensitive device in accordance with the present invention. Alternatively, the touch sensitive device can be a display screen, such as a liquid crystal display screen containing liquid crystal, which can be used to excite or sense the helper wave. The display screen can present information about the contact. [Embodiment] FIG. 1 illustrates a touch sensitive device 1A including a transparent touch sensitive panel 12 mounted on the display device 14. Display device 14 may take the form of a television, an electric moon screen or other visual display device. A touch pen 18 in the form of a pen is used to write text 20 or other content on the touch sensitive panel 12. 127365.doc -15- 200817987 The transparent touch sensitive panel 12 is a component capable of supporting bending wave vibrations, such as an acoustic device. As shown in Fig. 2, four sensors 16 for measuring bending wave vibrations in the panel 12 are mounted on the lower side of the panel. The sensor 16 takes the form of a piezoelectric vibration sensor and will mount a sensor at each corner of the panel 12. At least one of the sensors 16 can also function as a launch transducer for exciting bending wave vibrations in the panel. In this way, the device can be used as a combined speaker and touch sensitive device. A mounting bracket 22 made of foamed plastic is attached to the underside of the panel 12 and extends substantially around the perimeter of the panel 12. The mounting bracket 22 has a viscous surface so that the component can be securely attached to any surface. The mechanical impedance of the mounting bracket and the plate is selected to minimize bending wave reflection at the edge of the board. The relationship between the mounting frame and the mechanical impedance of the plate can be approximated by considering the -dimensional model shown in Figure 3. The model includes a waveguide 34 in the form of a beam that terminates in an edge mount 36 having a termination impedance. The incident wave 38 traveling downward along the waveguide 34 is reflected by the mount 36 to form a reflected wave. The plane waves of the incident and reflected waves traveling in a direction perpendicular to the edges. It is assumed that the mounting strip 36 meets the following boundary conditions: (i) the terminating impedance is only coupled into the transverse bulk' ie it does not provide any torque [Ϊ force; thus the bending moment is equal to zero at the edge, and (ii) the transverse shear force at the edge The disc pro- 〇, the ratio is equal to the terminal impedance; the reflection coefficient of the women's surgery is given by: R(cd) = / ZR (ω) a j Ζτ / ΖΒ〇) + ι where ZT is the termination of the mount , impedance, and zB is the force of the end of the waveguide, given by 127365.doc 200817987 ζβ(6,) = β^Μ(1+〇2ω where k(«) is the wave vector, which is bent according to the panel Hardness 3 and mass/Z per unit area,

Therefore, the reflection coefficient depends on the ratio of the end of the waveguide to the impedance of the mount. In addition, the impedance of the waveguide is proportional to the square root of the frequency and has real and imaginary components of equal weight (i.e., π/4 phase angle). Therefore, the reflection coefficient ρ can be greatly related to the frequency. If the following conditions are met, the reflection coefficient disappears, that is, the bending wave energy is strongly absorbed in the frequency band around (7): Ο ζτ = - iZB 〇 0) Therefore, the termination impedance of the mount must have both real and imaginary components, or etc. Effectively' the mount must be both resistant and compatible. The plate may be, for example, a 1 mm thick polycarbonate sheet having a mass per unit area of // 1.196 kg m·2 and a bending hardness of β = 〇·38 Nm. The U-upper equation can be used to calculate the impedance of the plate and strongly absorb the impedance of the absorber required for the selected angular frequency called =2; r (900 Hz) around the bending wave energy. The impedance per unit width of the board (approx. 1 mm beam) is · ZB (%) = (l + i) 33.8 N s π Γ 2 〇 The characteristics of the absorber providing the required absorption are thus: resistance per unit width,

Re(ZT)=Im[ZB〇0)] = 33.8 N s ηΓ2 硬度 Hardness per unit width, 127365.doc -17- 200817987 -i Im(ZT)%=Re|;ZB (must. still.) 1 91χ1〇5 Ν m.2. The reflection coefficient is a unitless complex number. Figures 4a and 4b are graphs illustrating the reflection coefficient R (the amplitude and phase as a function of frequency. When approximately equal to 900 Hz, the amplitude of the reflection coefficient is Zero, the phase of the reflection coefficient is inverted.

图 In Figures 5a and 5b, the panel 12 has a uniform surface seam and is in the form of raised surface patterns 28,29. Dragging the stylus 18 ′ along the path 3 〇 across the surface creates a bending wave 32 in the component as the stylus 18 passes over the pattern _ convex portion or line. Thus the contact of the stylus 18 provides a source of bending wave vibration in the component. In Fig. 5a, the 'surface pattern 28 is a periodic pattern of raised intersections and lines, and in Fig. 5b, the surface of the surface of the ο0 达 T 面面 pattern 29 is a random relief pattern 0 in Figures 2, 5a and 5b. In an embodiment, the f-curved wave is isotropically radiated from the contact point in the component as the contact moves over the surface of the coarse wheel of the component. The displacement of the component from the contact point at distance X is related to the displacement at the contact point by the _ turn (four) number Η(ω; X). At a distance greater than the wavelength into = 2 Wk (at a time, the transfer function can be approximated,

Η(0>,χ)= __Factory A lkfV/>W ^(ω)χ is a constant and k(6° is the previously defined wave vector. Although it is said that H(.;x) is only applicable. The bending wave on the infinite plate, but because the mounting frame strongly absorbs the f-curve vibration, the relationship is satisfied. If a bending wave source emits - pure sinusoidal frequency, the angular frequency is:: for the source 'at the distance Xl The phase difference Δθ12 between the two positions at X2 and the displacement of the contact point is 127365.doc 200817987 exp(iA(912) = exp[ik(6>0)(x1 - χ2)] which means the phase angle difference , the difference in path length such as gas XU) and the following relationship between an integer η12. Αθη =: ^ ~(92 = k(ty0)Ax12 + 2mn Figure 6 illustrates the steps in the method of determining the contact position using this equation · a) use each sensor to measure a bending wave signal to provide measured bending wave signals Wi(1) and Wj(t), b) calculate the phase angles (1) and (1) of the measured bending wave signals %(1) and Wj(1), C) Calculate the difference between the two phase angles 0i(t) and 0j(t), d) calculate the contact position from the following formula; = Αθ1} - 2m{- Figure 7a illustrates the schematic of a device FIG., The means for calculating the bending wave Wj⑴ sensing device such as one of the measured phase angle θ. " %(1) is a random signal and is therefore uncorrelated during long-term calibration. This signal is first amplified by amplifier 42 and then processed by a class of bandpass filters 44 whose passband is (7). Centered, and the bandwidth is △ still. The moving source of the test curve can prove the D〇ppier effect, in which a bending wave emitted by a source having a frequency % and moving by a velocity 〃 toward a point on the component has %_k(iy())v when it reaches the point. A different frequency is defined. Therefore, the maximum angular frequency offset between the bending waves at two different points on the part is 2k (%) vmax, where Vmax is the maximum speed of the moving source. If the angular frequency offset becomes larger than the width of the band pass filter, the above phase difference equation does not hold. Therefore, the bandwidth Δ(7) of the filter 44 is set to be larger than the maximum 127365.doc -19-200817987 frequency offset, and thus the following relationship is satisfied: » 2kK) vraax is processed by the chopper 44. The signal %(1) has a frequency W. The amplitude and phase modulation carrier is defined by:

Wj (1) = Aj (t) sin [must. t + 0j(t)] , and j(t) and Gj(t) are the amplitude and phase of the #. During the time scale = fluctuation depends on the bandwidth of the filter, ie the heart. The maximum frequency that can be measured from the bandpass filter for independent phase angle measurement is &. Since the touch sensor typically provides an updated contact position measurement every 10 ms, the minimum frequency of the position measurement is Δί < 10 ms. The transmitted signal W,j(t) is then simultaneously sent to two analog phase detectors. Such detectors are well known in the art, for example, see Horowitz and Hill, "Electronic Technology," page 644. Reference signals each having a frequency but having a phase difference of; r/2 are also fed to the two phase detectors. The output of the phase detector passes through a low pass filter 48 each having a cutoff frequency of about Δα/2. The output of the low pass filter is proportional to c 〇 s (0j) and sin (ej), respectively. These outputs are then digitized by the digitizer 50 and processed by the processor 52 to provide a phase angle of one. Figure 7b illustrates how the reference signal used in Figure 7a can be generated. A second bending wave signal Wi(t) is measured at a second sensor. The signal is fed through an amplifier 42 and an analog bandpass filter 44 to produce a filtered signal W'j(t). The filtered signal w,j(t) forms a reference signal that is fed directly to a phase detector 46. The filtered signal is also fed via a device to a second phase detector 46 which shifts the phase of the signal by ^/2. Let 127365.doc -20- 200817987 use the phase offset 仏 tiger as the second phase detector (10) reference signal. It is used to explain the phase angle difference and thus how the path length difference is used to count the contact position. The equation of Figure 6 can be overlaid on the hyperbolic curve on the plate 12. Figure 8a illustrates the use of a skewed pair of senses 16 (one of each end of the short side of the panel 12); ^ @ Μ an unambiguous value and three calculated differences in phase angles譬 _ 9 < mu, double line 26. Similarly, Figures 8b and 8c illustrate a double Ο 曲线 curve 26 resulting from a difference in phase angle between two pairs of other sensors and a different value of ~. Figure 8 illustrates all hyperbolic curves produced by the sensor. Contact position 24 is the intersection of three hyperbola, each pair of sensors corresponding to a double hyperbolic line. The correct value of ^ can be inferred from the contact location 24. The method of inferring 〇 can be implemented using a specific embodiment not shown in FIG. The bending wave signal shame (1) measured by each sensor is processed by two bandpass subtraction writes. Two phase angles are calculated, one for each pair of choppers', for example, as described in FIG. The chopper...having a slightly different pass f frequency provides two phase angle differences by each pair of sensors, each passband frequency corresponding to a difference. The phase angle difference Δ&, 4 of the sensor can be defined as: = Ηω0 + ωδ ) Δχ + Aθb:=^ω0^ωδ)Ax^2mh combination: where Δχ is the single defined by the contact and sensor position Path length difference. The correct combination (na, nb) can be used to minimize the following expression: A0a - 2; ma Aeb - 2mh Κ ω0 + ω δ) ) ^ {ω^ωδ) The path length difference can be estimated as: 127365.doc -21 . 200817987 Δχ A^a~2^na ^ A9h-2Tmh 2 ^ k(<2>0 + co5 ) k(it)0 —6?^) Another pair of sensors can be used to determine a path The difference in length defines the parent point of a hyperbola on the panel as the contact position. As shown in Figures 8a through 8j, the intersection of the largest number of hyperbola is likely to be the true second path length difference. Each. These two hyperbolas draw a hyperbola and the contact position. Figure 10 illustrates an alternative method for calculating the contact position from the above equation:

Ο i. Measurement - for bending wave signals 1 (1) and (1), each signal is measured by a sensor; ii · Calculate the correlation function of the dispersion correction of the two signals using the method described in Figure MUa; The correlation function of the dispersion correction calculates the initial position of the contact, as described in Figures 11 and 1 la; iv. Re-measures the bending wave signals Wi(1) and Wj(t); v. Calculates the phase angle of each signal—for example, as shown in Figure Vi. Calculate the difference between the phase angles; vii·Select the i value that minimizes the variation of the path length difference; viii·Draw a hyperbola defined by: k(to0)A^ij - 2πη^ IX. Repeat steps (iv) to (viii) to re-measure the bending wave signal at regular intervals (for example, Δt = 2; r/^). In step (Viii), the minimum of the two hyperbola from several pairs of different sensors is required to determine the contact position. Therefore, it is necessary to have the entire program for at least two pairs of sensors at the same time. Therefore, the minimum of the two phase angle differences must be determined. 127365.doc -22-200817987 The values are as shown in Figure 9, which produces two phase angle differences by using two sensors and splitting the signal into two bands. Alternatively, multiple sensors can be used to calculate multiple phase angle differences using pairs of different sensors. Figure 11 illustrates a method of calculating the correlation function of the dispersion correction to show the difference in path length between the contact position and the sensor. The method presented below outlines the information in PCT/GB2GG2/G()3G73. The method comprises the steps of: (a) measuring two bending wave signals Wi(1) and W2(t); (b) calculating a Fourier transform of W1(1) and W2(1) to obtain (9)(8) and %(4) and thus obtaining an intermediate function "one; its W(8) is The complex total Fourier transform 't represents time' α is 2; rf, where ^ is the frequency. (4) Calculate a second intermediate function, which is a function of the agricultural (8) hook (10) (d) and (e) while performing the step (a) s (c), using a predetermined panel dispersion relationship k = (A/B) ) 1/4' to calculate the frequency extension operation avatar / hour / 4". (f) group ^ ^ (four) and coffee = = to get the correlation function of the dispersion correction · · G (〇 = I £ M[f( Iy)]exp(iiyt)diy; and (g) plot the correlation function of the dispersion correction according to time, the peak occurs at time ti2' as shown in Fig. 11a; 〇) from Δ, ΔΧΐ2 is from the first The path length difference between the path lengths Χι and x2 of the contact with the second sensor. (1) Δχ] 2 疋 a hyperbola, which can be plotted as shown in Fig. 7 to calculate the contact position. If the method of Fig. 10 is used, The minimum of the two hyperbola is required to determine the contact position. Therefore, the above method of generating more hyperbola can be applied to this method. 0 127365.doc -23· 200817987 The first intermediate function Μ(8) can simply be the clip (8): (8) , which can provide a standard deviation correction correlation function. Or, Μ (can be selected from the following functions, all of which will produce standard deviation Equivalent function of the phase correction correlation function: c) M⑻ = Free ⑻ ancient 2 »|| Free first ⑻ > :) | j wherein 〆χ) is a real-valued function

d) Μ(8)= Disaster (10) Ancient 2»(8), where (8) is a real-valued function or Μ( can be a function ό(4), which is the Fourier transform of the correlation function D(1): ο(ΐ)〇(ί + ί,)\ Ν2 (〇ώ, these steps are to calculate D(t); calculate & call and apply a frequency extension operation to obtain the correlation function of the dispersion correction: G(t) = go to Ren as (8) (four) (four)) such as poor or, 1 In step (f), the following correlation function of the dispersion correction can be calculated: G(t) = 5 f>i[f (10) tear [f(WM2[f (4) which (10)) d (7) where private 2 (8) = forgiveness » 』(_χρ[-ϋί(ω)Δχ ]

j JJ where {9(4)} and {} are the two measured Four-Dimensional and Four-Fourier Fourier transforms of the bending wave signal {Wi"(1)} and {W2,j(t)}, and {know] is the path length difference. ^ - The sensor can be regarded as a first-and second-sensor, wherein the correlation function of the dispersion correction is an auto-correlation function. The autocorrelation function can be calculated by applying the same steps to the correlation function of the dispersion correction using W1(1), (1). 127365.doc -24- 200817987 Figure 12a shows a touch sensitive device that also serves as a speaker. The figure illustrates a method for suppressing the contribution of an audio signal to a processed signal that has been processed by dividing the audio signal and the measured signal into two different frequency bands. The device includes a device 106 in which a bending wave is generated by a transmit transducer or driver 108. The reflection converter applies an audio signal to it. Element 106 is used to produce an output. The audio signal is filtered by a low pass filter 112 prior to application to the component, as shown in Figure 12b, which removes the audio signal above the critical frequency f〇. As shown in Figure 12b, the contact produces a signal whose power output is substantially constant over a larger frequency band. The signal from the contact is summed with the audio frequency to obtain a combined signal that passes through the high pass filter 114 to remove signals above the critical frequency center. The filtered signal is then passed to a digitizer 116 and a processor 118. BRIEF DESCRIPTION OF THE DRAWINGS The present invention is schematically illustrated in the accompanying drawings in which: FIG. 1 is a schematic plan view of a touch sensitive device according to an aspect of the present invention, and FIG. 2 is a schematic view of the device of FIG. Figure 3 is a schematic side view of a one-dimensional beam; Figure 4a is a graph illustrating the amplitude versus frequency (Hz) of the reflection coefficient, since the amplitude is a ratio, there is no unit; the graph is the phase of the reflection coefficient (in terms of Graph of radians (in radians) versus frequency (Hz); Figures 5a and 5b are schematic perspective views of alternative touch sensitive devices; 127365.doc -25- 200817987 Figure 6 is a flow chart of a method for finding contact locations in accordance with the present invention Figure 7a is a schematic block diagram of an apparatus for calculating a phase angle; Figure 7b is a schematic block diagram of an apparatus for use with a device incorporating W7a; Figures 8a to 8d are plan views of a device according to the present invention, illustrating a difference in path length Figure 9 is a schematic block diagram of an alternative device for calculating a phase angle, and Figure 10 is a flow chart illustrating an alternative method of calculating a contact position;

11 is a flow chart of a method for calculating a contact position using a correlation function of dispersion correction; FIG. 11a is a graph of correlation function of dispersion correction versus time, and FIG. 12a is a schematic block of a touch sensitive device that doubles as a speaker operation. Figure, and Figure 12b illustrate a method of separating an audio signal from a measured bending wave signal in the apparatus of Figure 12a. [Main component symbol description] 10 Touch sensitive device 12 Touch sensitive panel 14 Display device 16 Sensor 18 Stylus 20 Text 22 Mounting bracket 24 Contact position 26 Hyperbola 127365.doc Ο 200817987 28 Raised surface pattern (periodic 29 raised surface pattern (random) 30 path 32 bending wave 34 waveguide 36 edge mount 38 incident wave 40 reflected wave

ϋ 42 Amplifier 44 Analog Bandpass Filter 46 Analog Phase Detector 48 Low Pass Filter 50 Digitalizer 52 Processor 54 Bandpass Filter 106 Component 108 Converter or Driver 112 Low Pass Filter 114 High Pass Filter 116 Digital Processor 118 processor 127365.doc -27-

Claims (1)

200817987, Patent Application Range: A touch sensitive device comprising: a component capable of supporting a bending wave; a plurality of solid sensors for measuring bending wave vibrations in the component, wherein each sensor Determining a measured bending wave number; 13: The processor calculates the position of the last contact of the component by the measured bending wave signal; the processor calculates each measured f-wave signal - a phase angle and a phase difference between phase angles of at least two pairs of sensors to calculate at least two phase differences and calculate a position of the contact from the at least two phase differences; wherein each pair of sensors is in phase The phase difference between the angles is determined by the following equation: ' △6L = Hk〇0)AXim + 2_m, where ^ and the heart are the phase angles of the individual measured bending wave signals, AXlm-X/-xw is the sensor pair The path length difference between the two sensors, X/X is the relative distance 'k (still) of the contact position to each of the two sensors is a wave vector and & is an integer. 2. The touch sensitive device of claim 3, wherein the component is an input device of a graphical user interface; the processor is operative to calculate the contact location using a signal associated with the expected contact location. 3. The touch sensitive device of claim 2, wherein the graphical user interface allows the user to see the position of the selection button for contact, 127365.doc 200817987 and the process n determines the contact position Any contact assumed to be on the component occurs within the selector button position. The contact sensitive device of claim 3, wherein the contact position is determined by a probability value of where the contact can be made. 5. The touch sensitive device of claim 4, wherein the probability value is based on the position, size and frequency of one or more of the displayed objects on the user interface. f ϋ & As in the touch sensitive device of the patent scope i, the sensor is a piezoelectric vibration sensor. 7. The contact sensitive device of claim 3, wherein the value of the individual path length difference is determined for each pair of sensors; two hyperbolic curves are defined by the values of the two path length differences, The intersections determined by the hyperbola define the contact position. 8·如中#Patent||The contact sensitive $f of item 7 further includes: - a plurality of bandpass choppers, and each of the sensors is measured by two bandpass choppers The bending wave signal is calculated and two phase angles are calculated relative to each sensor and two phase angle differences are calculated relative to each pair of sensors. 9. A method of determining the position of a contact on a part of a part that can support the bending of the skin. There are a plurality of sensors for measuring the bending fluctuations within the 4 parts. The steps of the method include: Applying one of the contacts on one of the components, the sensors respectively measuring the bending wave signal; and utilizing at least one path length of each sensor pair of the at least two sensor pairs 127365.doc 200817987 path length The difference in position 4 of the measurement of the difference is determined by measuring the phase angle difference of one of the curved wave signals of the sensors of the pair of sensors. Οο. 11. The method of claim 9, further comprising: utilizing information about the expected location of contact when determining the contact location. The method of claim 2, wherein the component is a 1-shaped user interface, and the component displays a selection to the user, the contact position having a plurality of buttons; and the method further comprises: When the position is touched, it occurs that the button positions are set to be within any of the contacts on the component. 12. The method of claim 10, further comprising determining a probability value at which a contact may occur at a particular location, the contact location. For example, the method of claim 12, wherein the probability that the contact occurs at the U position is based on the position, size, and frequency of one or more of the displayed objects on the graphical user interface. 14. The method of claim 9, wherein the phase difference between the phase angles of the pair of sensors is determined by the following equation: · A6im - θι-θπι — k(6>0) Axim + 2^mm , where ^ and ' are the measured phase angles of the bending wave signals ΔXlm=X/-X, which are the path length difference between the two sensors in the sensor pair 'X/ and Xm are the contact positions To the relative distance of the two sensors, k((7)〇) is the wave vector and ^ is an integer; and 127365.doc 200817987 The method further comprises: estimating a Φ A using a state space estimator A contiguous sequence of ^1 ^ m and a contiguous sequence with the greatest probability of being set is selected in the sequence. 15. If the patent application is in accordance with item 14 of the patent scope, / or further, the state space estimator is used to continually construct a pair of roads, and the pair of roads are different. Only length. Specifically, regardless of the location and speed of the contact. 16. If you apply for the method of item 15 of the patent, enter the cow to select a positive ^ 乂匕. 1 'the state space estimator for the correct sequence Give a maximum likelihood measurement. 17. If the scope of patent application is 14th, the law 'where the state space estimator uses a random walking mode as a statistical description of the action of the contact mode 0, 18. = the method of claim 9 of the patent scope, where - The processing of detecting the position of the contact is performed in the processor. Ο 19. The method of claim 9, wherein each pair of sensors measures a value of a long path of production and is defined by a value of two path length differences. The two warpings ^ hyperbola ' define the contact position by using a point and point determined by the hyperbola. The method of claim 19, further comprising: i, the device measuring the bending wave signal using a plurality of band pass filters of the knife; calculating the f curve wave signal measured by the mother sensor Two phase angles 'the one of the exclusive fe A- angles corresponds to each bandpass filter; and 127365.doc 200817987 provides two phase angle differences for each pair of sensors; for each pair The two phase angle differences of the sensor are used to calculate the value of the individual path length difference for each pair of sensors. 21. The method of claim 9, wherein the processing of determining the contact position is performed in a processor. Γ 127365.doc