WO2008138208A1

WO2008138208A1 - Multiple points touch positioning method

Info

Publication number: WO2008138208A1
Application number: PCT/CN2008/000845
Authority: WO
Inventors: Ruxi Lu; Chunjing Zhou; Junming Li
Original assignee: Vtron Technologies Ltd.
Priority date: 2007-05-16
Filing date: 2008-04-25
Publication date: 2008-11-20
Also published as: CN100590579C; CN101105733A

Abstract

A multiple points touch positioning method for a touch screen system, comprising the following steps: a?measuring a touch signal, judging a change instance of the signal, calculating a position coordinate occurred a touch event and/or a shape size of a touch point; b?according to the change instance of a position coordinate number, judging whether the touch information is a single point touch or a multiple points touch, if it is the single point touch, then the touch screen system accordingly performing every operation of the single point touch, if it is the multiple points touch, then the method turns into the step c; c?comparing the change of the position coordinate number and/or the change of the coordinate value detected in the present calculating period and the previous calculating period, judging whether there is a new touch point added or not or whether there is a touch point leaving or not, if there is a new touch point added, registering the new touch point information, recording the position coordinate of the new touch point, if there is a touch point leaving, then logouts the leaved touch point information.

Description

Multi-touch positioning method

The present invention relates to a touch positioning method for an interactive display system, and more particularly to a multi-touch positioning method that can distinguish simultaneous operation of a plurality of touch points. Background technique

At present, touch screens have been widely used in many occasions and fields as an input device instead of or in addition to ordinary keyboards and mice. In existing touch screens, the location detection technique for detecting touch locations can be based on different technologies, including infrared, camera, surface acoustic waves, and the like. Users usually do not need special operation training, and only need to press the touch screen at the location marked with the icon to implement a series of complicated instructions.

In order to calculate the location at which a touch event occurs, the touch screen system typically determines the location of the touch by measuring changes in the touch system detection component or unit output signal, and calculates the position coordinates of the touch point. In the current touch system, the touch screen detection system only receives a unique set of position coordinate data in a given time period, so that the position of the touch point can be accurately determined in the calibrated touch screen system, and no report error occurs. Touch the location. If two or more touch locations are pressed during a given time period, multiple touch signals will overlap during the time period. If the signals are not directly selected to calculate the touch location, the detection will be made. The touch location reported by the system is not the actual touch location. As shown in FIG. 1 , 101 is a conventional touch screen system using an orthogonal matrix detection method. The touch screen system may adopt infrared positioning technology or other technologies, and the detection system detects a touch event occurring at the first location 102 on the touch screen, and generates The first set of positioning coordinate data determines the actual location at which the first touch event occurred. When the user leaves the first touch location 102 and touches the second location 103, a second set of touch signals is generated to determine the actual location at which the second touch event occurred. If both the first touch location 102 and the second touch location 103 are pressed within a given time period, the first set of signals and the second set of signals will overlap during the time period, and the detection system will calculate multiple position coordinates. Data, the resulting touch location may be one of 102, 103, 104, 105, such that the touch screen system will report the wrong touch location and will not respond correctly to the user's operation.

Such a situation not only occurs in touch screens employing orthogonal detection and positioning techniques, but also in touch screen systems using other principles. As shown in FIG. 2, 201 is a touch screen system for determining coordinates of a touch point position by calculating an angle, and the touch screen system may employ multiple camera positioning technologies or other technologies, and the touch screen system detects the first

1

Confirmation When a touch event of the touch location 202 is touched, the actual location where the touch event occurs may be calculated according to the angle relationship. When the user touches the first touch location 202 and touches the second location 203, the touch screen system can also calculate the touch event. The actual location where it occurred. If the first touch location 202 and the second touch location 203 are both pressed within a given time period, the detection system will calculate a plurality of position coordinate data, and the possible touch locations thus obtained are 202, 203, 204, 205. One of them, because the existing touch screen detection system only receives a unique set of position coordinate data, the touch screen system will report the wrong touch position, which directly leads to the wrong user input instruction.

For the above reasons, existing touch screen technology will fail in some cases. For example, some common functions for ordinary keyboards are generally not seen in current touch screen systems. For example, pressing two or more buttons at the same time can enter a dedicated keyboard function to perform a specific operation. Also for example, in a video game played by two or more players, the player desires to simultaneously input information using a single touch screen. While each person can use a separate predetermined touch screen portion during game play, there are many overlapping touch phenomena when each person operates their touch screen portion, which may cause the game response to be inconsistent with the wishes of one or more players. Although this situation can be improved by some means, such as letting everyone use a separate dedicated touch screen, this method does not solve the problem ideally due to factors such as cost, space constraints, and functions. In the above and many other examples and applications, touch algorithms based on single-touch responses are unable to properly respond to multiple simultaneous touches, thus greatly limiting the application of touch screens in such situations.

In view of the above-mentioned deficiencies of the current touch screen system, it is necessary to provide a method for realizing multi-touch positioning. Summary of the invention

The object of the present invention is to provide a multi-touch for a touch screen system, which can recognize two or more touch operations, and can also report an effective touch position when multiple points are simultaneously touched, in view of the problems existing in the prior art. Positioning method.

In order to achieve the above object, the present invention adopts the following technical solution - a multi-touch positioning method for a touch screen system for discriminating simultaneous touch events of two or more points, including the following steps:

a, measuring the touch signal, judging the signal change, calculating the position coordinates of the touch event and

/ or the size of the touch point; b. determining whether the touch information is a single touch or a multi-touch according to the change of the number of position coordinates, and if the touch is a single touch, the touch screen system performs the operations of the single touch correspondingly, if it is a multi-touch, Go to step C;

c. Compare the change of the number of position coordinates detected by the calculation cycle and the previous calculation cycle and/or the change of the coordinate value, determine whether a new touch point is added or has a touch point to leave, if a new touch point is added, register New touch point information, record the position coordinates of the new touch point, if there is a touch point to leave, cancel the touched point information that has left; d, compare the coordinate value (X, Y) detected in the calculation period and the previous calculation period Change the situation, compare the coordinate value (Χ, Υ) with the current position coordinates of the already registered touch point, and judge the motion of each touch point;

e. Calculate and judge the touch point where the position changes, and assign the latest coordinate value to the touch point.

In the above steps, according to the actual application, only a few of the steps may be selected instead of using all the steps. For example, when it is only necessary to judge a plurality of touch points, it is not necessary to judge the movement of each point, and only the Step a to step c, when it is necessary to judge the movement of a plurality of points without reproducing the motion trajectory of each point, only steps a to d can be used. By applying the multi-touch positioning method of the present invention, when the touch screen system touches an event while discriminating two points or more points, when the detection speed is fast enough, it can be distinguished that the "simultaneous" occurrence of the touch event is The difference in time, according to the order of the touch events, first determine the coordinate value of a touch point, register it and save it, when the next touch event occurs, according to the position coordinate value calculated by the touch screen system, combined with the registered touch point The position coordinates, analyze and separate the position coordinates of the new touch event, so that the coordinate recognition of the new touch point can be completed. After the respective touch points are correctly identified, a plurality of simultaneously operated touch points are tracked and recognized according to the change of the touch position coordinates detected by the touch screen system, thereby realizing effective recognition of the position coordinates after the movement of the respective touch points.

Further, the method for determining whether the touch information is a single touch or a multi-touch in the step b is: if there is only one set of position coordinate values within a certain period of time, it is determined to be a single touch, if it is detected within a certain period of time When there are two or more sets of position coordinate values, it is considered that there are multiple touch points.

In order to better distinguish multiple touch points, one method that can be adopted is: determining the coordinates of the touch point position, and the number of detecting units in different coordinate directions (X, Y direction) caused by the touch point when touched / or numerical change law, detecting the shape and size of the touch point, marking according to the shape size and further identifying different touches Touch it. The detection method of the shape of the touch point differs depending on the specific detection technique. For a touch screen using multiple cameras or lens positioning technology, by detecting the distance of the touch points from the respective cameras, combined with the shape of the touch points captured by the camera, the shape and size of each touch point can also be calculated.

In step C, since the change of the touch point is random, the situation is more complicated, and there may be a touch point to leave while a new touch point is added, and the determination, registration, and logout of the new touch point need to be used according to the use. Targeted solutions are developed for occasions or areas of use, often requiring trial and error to determine a defined method or mechanism that is more consistent with actual use. But no matter what, seemingly simultaneous events, as long as the detection speed is fast enough, through subdivision, the order of events can always be distinguished. The method for calculating and determining the touch point of the position change in the step e includes the following steps:

i, calculating a coordinate position (X, Y) of the touch position according to the measurement signal;

Ii. Calculate the distance between the coordinate value (X, Y) and the current coordinate of each adjacent touch point, wherein the distance from the first point η is A, and the distance between the second point ₂ is

D ₂ , ..., the distance from the nth point 7;

D ₂ =

,

D„ =

,

i ii, comparing the calculated distance values A, D ₂ , ..., D _n , finding the minimum value Z) _m , where D _m =Mi" £ , D ₂ , ... D„ , determining the corresponding to Z _m Touch point 7 where the position changes;;

Iv. Replace the existing position coordinates of the touch point 7 with the smallest distance value with the position coordinates (X, Y) detected in the current calculation cycle.

The method for judging the touch point Γ „ (χ, y) adjacent to the coordinate value (X, Y) in the step ii is adopted by detecting a range in which the coordinate value changes, detecting a rate at which the coordinate value changes, or detecting a change in the coordinate value. The direction trend method is used to determine.

The touch location detection technology used in the present invention is an infrared technology, a camera technology or other technologies. Compared with the existing single-touch technology, the multi-touch positioning method of the present invention has the following advantages: 1. Multi-touch positioning can be realized without increasing hardware cost. Second, the touch screen can be used for various detection principles, especially the touch screen using infrared positioning and camera positioning technology.

Third, the application is more extensive. It can realize single touch and multi-touch, and can complete multi-person simultaneous operation functions that cannot be completed by existing touch screens, and can be applied to more fields and occasions.

DRAWINGS

1 is a schematic diagram of a touch screen operation in the prior art;

2 is a schematic diagram of another touch screen operation in the prior art;

3 is a schematic diagram of two points in touch according to an embodiment of the present invention;

4 is a schematic flow chart of an embodiment of the present invention;

Figure 5 is a flow chart for determining the movement of a touch point in accordance with the present invention. detailed description

According to the multi-touch positioning method of the present invention, for the touch screen system shown in FIG. 1, when the touch events occur simultaneously with 102 and 103, the first touch event is first recorded according to the difference in the timing of the occurrence of the touch events 102 and 103. The coordinates of the place of occurrence are (xl, yl ), register and save this touch point. When the second touch event is superimposed on the first touch event, the system detects multiple sets of position coordinates (xl, x2, yl, y2), thereby judging that a new touch point is added, by comparing the existing registrations. Point position coordinates (xl, yl), excluding the possibility of other coordinates (xl, y2), (x2, yl), thereby determining the coordinates of the newly added touch point is (x2, y2), so that two touches can be distinguished Points 102, 103.

Similarly, for the touch screen system shown in Fig. 2, the two touch points 202, 203 can be more easily distinguished by applying the method of the present invention. The methods and steps are as described above and will not be described here.

Fig. 3 is a specific embodiment of the method of the present invention in which two points are simultaneously touched, which occurs in the case of simultaneous writing by multiple people or multiplayer games. Referring to FIG. 3, 301 is a touch screen device. The location detection technology used by the touch screen device may be infrared technology or camera positioning technology or other technologies. 302 is a touch point whose trajectory of the touch operation is 303. In another location, another touch point 304 is also operating on the same touch screen, the touch point 304 may be from the same user or from a different user, 306 is a touch location of the touch point 304 at a certain time, the trajectory of its operation It is 305. In the touch screen of the prior art, since only a single touch can be responded, when only one touch point 302 or 304 is on the touch screen The touch screen can work normally during operation. For the case where the two touch points shown in the illustration are simultaneously touched, the touch screen will not be able to report the correct touch location, and an erroneous response will occur.

The process in which the touch event is judged and recognized will be described below with reference to FIG.

Referring to FIG. 3, touch points 302 and 304 are simultaneously operated on the touch screen. When the touch point 302 and the touch point 304 are recognized, the detection system may first determine a touch event of the touch point according to the order in which the touch event occurs, and register the coordinate position thereof. And saving; in the next calculation cycle, according to the calculated touch coordinate value, compared with the touch coordinate value that has been registered and saved, the touch position coordinate value of the other touch point is separated from the calculated touch coordinate, and the same is also Register and save. In this way, the touch screen system completes the distinction and recognition of the two touch points, and then the tracking trend of the plurality of simultaneously operated touch points can be tracked and recognized according to the change of the touch position coordinates.

4 is a schematic flow chart of a multi-touch implementation method according to an embodiment of the present invention, which mainly includes the following steps: a. The touch screen detection system measures a touch signal, determines a signal change, and calculates a position coordinate ∑ (X, Y) at which a touch event occurs. It may contain one or more sets of coordinate data, which is a collection of coordinate data; if necessary, the shape and size of the touched point can also be calculated;

b. According to the change of the number of position coordinates, determine whether the touch information is a single touch or a multi-touch. If there is only one set of position coordinate values (X, Y) within a certain period of time, it is judged as a single touch, and the touch screen system correspondingly Perform various operations of single touch, such as writing, clicking, etc. If the detected position coordinate value is more than one set within a certain period of time, it can be judged that there are multiple touch points, proceed to step c; c. Compare the calculation The change in the number of position coordinates detected by the cycle and the previous calculation cycle and/or the change in the coordinate value, to determine whether a new touch point is added or touched to leave, if a new touch point is added, registering a new touch point information, Record the position coordinates of the new touch point. If there is a touch point to leave, the information of the touched point is cancelled. To track and identify the position of each touch point, the position coordinates of each touch point are recorded in the pth calculation period, the first The point record is 7 (Xp, YP), the second point is recorded as 7 (Xp, Yp), ... the Nth point is recorded as T _n (Xp, Yp );

d. Compare the change of the coordinate value (Χ, Υ) detected in the calculation cycle and the previous calculation cycle, compare the coordinate value (Χ, Υ) with the current position coordinate of the already registered touch point, and judge each touch point. Situation of movement;

e. Calculate and judge the touch point where the position changes, and assign the latest coordinate value to the touch point. In this embodiment, the preset is predicted to be two touch point operations, and in step 3, the new touch point is identified. And registration can be achieved by monitoring the change in the number of touch coordinate values, which is relatively easy. However, if there are more than two touch point operations, the change of the touch point is random, and the situation is more complicated. When the touch point leaves, a new touch point may be added, and the new touch point is discriminated. Registration, registration, and cancellation require a tailored solution based on the location of the touch screen or the field of use. Usually, trial and error can be used to determine a more appropriate judgment method or mechanism. But fundamentally, events that seem to occur at the same time, as long as the detection speed is fast enough, through subdivision, the order of events can always be distinguished.

Referring to FIG. 5, the method for determining the position coordinate change of the touched point in step 5 mainly includes the following steps: i. Calculating the touch position coordinate position (X, Y) according to the measurement signal.

Ii. Calculate the distance between the coordinate value (X, Y) and the current coordinate of each adjacent touch point, where the distance from the first point 7; is Z^, and the second point: Γ ₂ The distance between A, ..., and the nth point 为 is

= l[T ₂ (x) - Xf + [T2(y) - Y] ² ,

D„

,

In this embodiment, the touch event occurs at each touch point is continuous, and the touch point 7 adjacent to the coordinate value (X, Y); (X, y) can be determined by detecting the range or detecting the change of the coordinate value. The method of changing the rate of the coordinate value, that is, setting the range of the coordinate value in each calculation period in advance, and when the (X, Y) value falls within the range of the coordinate value of a certain touch point, it can be considered as The touch point is near the coordinate value, Y), and it may be that one of the touch point positions moves. If the touch event occurring at each touch point is discontinuous, the method of determining the touch point 7 (X, y) adjacent to the coordinate value (X, Y) is determined in conjunction with the actual use of the touch screen.

Iii. Compare the calculated distance values A, A, ..., . „, Find the minimum value ^, D _m =Min(D _{i ;} D ₂ , ... D„ to determine the touch point r _m that changes with the corresponding position. iv, the position coordinate is detected within the current calculation period (X, Y) instead of the touch point 7 with the smallest distance value; the existing position coordinates.

Through the above calculation, the touch point whose position has changed can be correctly found, and the touch coordinate is generated by the movement of the touch point 304, indicating that the touch point 304 has moved from the previous coordinate position to the position indicated by 306. Positive After identifying the position coordinates of each touch point, various touch operation functions can be defined according to the movement trend of each point. For example, in an application, two touch points move in opposite directions to indicate that the zoom operation is performed; when two touch points move toward each other, it means to perform a zoom-out operation; and one touch point does not move, and another touch point performs an arc motion. Indicates that a rotation operation or the like is performed. These operational functions can be flexibly defined by the corresponding application software.

This embodiment cites the case where two touch points are touched at the same time, and the touch operation recognition of two or more points can also be performed according to the above method, first distinguishing each touch point, registering and saving the position coordinate value, and then according to The position of the position coordinate value changes to determine the touch point where the position changes. The shape of the touch point can also be detected if necessary, and each touch point is further marked and further identified according to the shape size.

The method of the present invention is applicable to a variety of different touch screen devices, including the touch location detection technology used therein as various touch screens based on infrared, camera or other technologies, although each touch screen technology differs in the principle of detecting touch input information. However, the technical idea and method of the present invention can be applied to various touch screen systems regardless of the position detection technology employed by the touch screen.

The above description is only one embodiment of the present invention. In fact, the use of multi-touch is far more than the ones mentioned in the embodiment; only two touch points are listed in the embodiment, which can be implemented according to the method of the present invention. The touch points may be two or more, and the scope of the present invention is not limited thereto, and any insubstantial changes based on the technical solutions of the present invention are included in the scope of the present invention.

Claims

Rights request

A multi-touch positioning method for a touch screen system for discriminating simultaneous touch events of two or more points, comprising the following steps:

a, measuring the touch signal, judging the signal change, calculating the position coordinates of the touch event and/or the shape and size of the touch point;

b. judging whether the touch information is a single touch or a multi-touch according to the change of the number of position coordinates. If it is a single touch, the touch screen system performs each operation of the single touch correspondingly, and if it is a multi-touch, enters Step c;

c. Compare the change of the number of position coordinates detected by the calculation cycle and the previous calculation cycle and/or the change of the coordinate value, determine whether a new touch point is added or has a touch point to leave, if a new touch point is added, register New touch point information, record the position coordinates of the new touch point, and if there is a touch point to leave, log out the touch point information that has left.

2. The multi-touch positioning method according to claim 1, further comprising the step of: comparing the change of the coordinate value detected by the calculation period and the previous calculation period, and the coordinate value and the already registered The current position coordinates of the touched points are compared to determine the motion of each touch point.

3. The multi-touch positioning method according to claim 2, further comprising the step of: calculating and determining a touch point whose position has changed, and assigning the latest coordinate value to the touch point.

The multi-touch positioning method according to any one of claims 1 to 3, wherein: the method of determining whether the touch information is a single touch or a multi-touch in the step b is: if, within a certain period of time, If there is only one set of position coordinate values, it is judged as a single touch. If there are two or more sets of position coordinate values detected within a certain period of time, it is considered that there are multiple touch points.

The multi-touch positioning method according to any one of claims 1 to 3, characterized in that: in determining the coordinates of the touch point position, the different coordinate directions (X, Y) are caused according to the touch point when the touch is touched. The number of detection units and/or numerical changes of the direction), the shape and size of the touched points are detected, and the different touch points are further marked according to the shape size.

6. The multi-touch positioning method according to claim 3, wherein: calculating and judging in step e The method of breaking the touch point of the position change includes the following steps:

i. calculating the coordinate position of the touch position according to the measurement signal;

Ii. Calculate the distance A between the coordinate values and the adjacent touch points Τ _π current coordinates, ·"·· · D _n ,

Ii i. Compare the calculated distance values A, A, ..., D„, find the minimum value Z) _m , and determine the touch point T _m where the position corresponding to D _m changes;

Iv. Replace the existing position coordinates of touch point 7 with the smallest distance value with the position coordinates detected during the current calculation cycle.

The multi-touch positioning method according to claim 6, wherein the determining method of the touch point adjacent to the coordinate value in the step ii is performed by detecting a range in which the coordinate value is changed, and detecting the coordinate value. The rate of change or the direction of the direction change of the detected coordinate value is determined.

The multi-touch positioning method according to any one of claims 1 to 3, characterized in that the touch location detecting technology used is infrared technology, camera technology or other techniques.