CN101697106B

CN101697106B - Auto-correction method of touch panel

Info

Publication number: CN101697106B
Application number: CN2009100356551A
Authority: CN
Inventors: 刘杰; 马里剑
Original assignee: Suzhou Pixcir Microelectronics Co Ltd
Current assignee: Suzhou Pixcir Microelectronics Co Ltd
Priority date: 2009-09-30
Filing date: 2009-09-30
Publication date: 2011-10-12
Anticipated expiration: 2029-09-30
Also published as: CN101697106A

Abstract

The invention relates to an auto-correction method of a touch type panel, comprising the following steps of starting the touch type panel, acquiring the summation of induction absolute capacitance values of all scanning lines of the panel, recording the minimum value thereof as an initiative value and providing the initiative value for the touch type panel. The auto-correction method of panel overcomes the defects of manually correcting the panel in the traditional method, is simple, can automatically regulate the touch type panel, and has stable operation without easily being interfered from the external environment and extremely high capacity of resisting interference.

Description

The automatic bearing calibration of contact panel

Technical field

The present invention relates to a kind of bearing calibration, refer in particular to a kind of automatic bearing calibration of touch panel.

Background technology

Along with high-speed development of science and technology, snafu variation has taken place in electronic product, appearance along with recent touch electronic product, the touch-control product more and more is subjected to pursuing of people, not only it can save the space, be convenient for carrying, but and the user by finger or pointer etc. direct control just, use comfortable, very convenient.For example, the common personal digital assistant (PDA) of existing market, touch-control class mobile phone, portable notebook computer or the like have all strengthened the input to touch technology, use so touch-control device must have more widely in every field in the future.

At present, capacitance type touch-control panel is because wear-resistant, life-span is long, and on light loss and system behavio(u)r, have more advantage, so capacitance type touch-control panel has been subjected to pursuing of market recently, various capacitance touching control screen products emerge one after another, thereby the principle of work of capacitance type touch-control panel generally is to come the capacitance variations of induction panel to judge the position and the action of finger by a touch-control chip, so just need know that panel doing reference without any the original capacitance under the input state, promptly do not have the finger or other object touching state under the original capacitance value as a reference, so just need a method of proofreading and correct panel, the method of at present common correction panel all is a manual calibration, promptly under the initial environment when touching without any input media, this influence value is write in the touch-control chip, but under initial environment, even without any input media, also can be subjected to as temperature, numerous influences of external environments such as humidity, be commonly referred to noise, so just there is instability in initial environment, in case initial environment changes like this, the operation of contact panel will be influenced, and normal condition can not be recovered.

Therefore need solve above problem for users provide a kind of easier method.

Summary of the invention

The actual technical matters to be solved of the present invention is the method how a kind of automatically calibrating contact panel is provided.

In order to realize above-mentioned purpose of the present invention, the invention provides a kind of automatic bearing calibration of contact panel, it may further comprise the steps: start this contact panel; The method of employing difference measurement is obtained the relative capacitance of induction of above-mentioned panel, obtains the induction absolute capacitance values of every sweep trace of above-mentioned panel again by the mode of integration; Obtain the induction absolute capacitance values sum of these all sweep traces of panel, write down its minimum value and, described initial value is offered contact panel as initial value; When the induction absolute capacitance values sum of described all sweep traces constantly changed, initial value was minimum induction absolute capacitance values sum all the time.

Method from the normal moveout correction contact panel of the present invention has overcome the method that conventional manual is proofreaied and correct panel, not only method simple, can regulate touch panel automatically, and be not vulnerable to the interference of external environment, have very strong antijamming capability.

Description of drawings

The variation diagram of induction amount when Fig. 1 is a contact panel without any input;

Fig. 2 is the variation diagram of contact panel induction amount during according to existing differential capacitance;

Fig. 3 is the variation diagram of the automatic timing induction amount according to the present invention;

Embodiment

The present invention is further illustrated below in conjunction with drawings and Examples.

At present common inductance capacitance adopts the method for difference measurement, so-called difference measurement is meant: after contact panel powers on, sweep trace begins scanning, without any the input media contact surface plate time, the variation of whole touch panel capacitance is tending towards a steady state value, as shown in Figure 1, when any input equipment such as this panel of finger touches, this capacitance will change, after scanning for the first time, when scanning again for the second time, two capacitances of same position have just formed a difference, have just so just formed, negative capacitance is arranged, promptly finally formed minimum and maximum capacitance, thereby can judge the position of finger, as shown in Figure 2.

The mode of above-mentioned difference measurement capacitance, just get the method for relative capacitance, through facts have proved, has more intense antijamming capability, but when calibrating panel automatically, whether the relative electric capacity of this kind really is difficult to judge has input media such as finger touches panel or noise is arranged, because when also touching when promptly not being suspended in the top of panel of finger, be subjected to the influence of inductance capacitance, also can form a differential capacitance this moment, when finger really touches this panel, can form a differential capacitance again, might the influence value when pointing that practical touch is not to panel be input to this moment in the chip in the panel, like this when finger is really touched this panel, operation is just unstable, occurs variety of issue easily.

From the above, if want contact panel to write down differential capacitance value accurately, just need carry out from normal moveout correction contact panel, the form of utilizing differential capacitance at present is that the form of relative electric capacity is difficult to judge whether input media or noise are arranged, so can adopt the mode of absolute capacitance in the touch surface plate automatic calibration.As long as because have any input media near or touch a contact panel, absolute capacitance values is to be increase tendency certainly, as shown in Figure 3, so just the position of minimum capacitance of original state can be deposited in the chip on the panel, thereby guarantee when the finger practical touch, can work normally.

The concrete principle of work that absolute capacitance is proofreaied and correct contact panel is: after contact panel powers on, promptly start this contact panel, the surface sweeping line begins scanning, at first need to adopt the method for difference measurement, obtain the relative capacitance of induction of this panel, then in the induction absolute capacitance values of further obtaining every sweep trace of this panel, wherein a kind of method is to utilize the mode of integration just can obtain the induction absolute capacitance values of every sweep trace, as the numerical value of establishing article one sweep trace induction absolute capacitance values T1 is raw (0), wherein establishing raw (0) is a reference value, it is T1=raw (0), the numerical value of the induction absolute capacitance values T2 of second sweep trace is raw (0)+raw (1) just so, and the like, article three, its numerical value of induction absolute capacitance values T3 of sweep trace be raw (0)+raw (1)+raw (2) just, so the induction absolute capacitance values Ti of i bar sweep trace with regard to be raw (0)+raw (1)+raw (2)+... + raw (i-1).The induction absolute capacitance sum of all sweep traces induction absolute capacitance values T1 that just is equivalent to article one sweep trace adds the induction absolute capacitance values T2 of second sweep trace like this, and addition successively directly is added to the induction absolute capacitance values of i bar sweep trace Ti.Like this when the inductance capacitance value changes, just obtain the induction absolute capacitance sum of all surface sweeping lines, write down its minimum value and, more described initial value is offered contact panel as initial value, thereby just finished panel from normal moveout correction, and then just can accurately judge whether input media.And when capacitance constantly changes, the induction absolute capacitance values sum of surface sweeping line also can constantly change, system can select minimum numerical value initial value the most automatically, thereby in continuous scanning process, in case found littler induction absolute capacitance values sum, then can abandon original numerical value, littler induction absolute capacitance values sum is deposited in the chip of panel, thus make from the mode of normal moveout correction contact panel just more accurate.

What need to replenish is, has at least the induction absolute capacitance values of a sweep trace to fix in the induction absolute capacitance values of described all sweep traces, is used to guarantee the induction absolute capacitance values of other sweep trace.Generally speaking, the induction absolute capacitance values T1 of above-mentioned article one sweep trace can be made as an invariable numerical value, in order to ensure T1 is that raw (0) is a steady state value, on the chip (Tango) of contact panel, need to look for a constant reference point of electric capacity, wherein a kind of implementation method is exactly to add two capacitor C 1 and C2 respectively on two sweep traces that are not used of entire chip, wherein, the inductance capacitance value Tc1 that connects the sweep trace of capacitor C 1 plays scan action, and the inductance capacitance value Tc2 of sweep trace that connects capacitor C 2 is as reference point.

Method from the normal moveout correction contact panel of the present invention does not need manual adjustment, and system will select minimum capacitance to be deposited in the chip of panel automatically, thereby judges whether the input media contact surface plate is arranged.

Claims

1. the automatic bearing calibration of a contact panel, it may further comprise the steps:

Start this contact panel;

The method of employing difference measurement is obtained the relative capacitance of induction of above-mentioned panel, obtains the induction absolute capacitance values of every sweep trace of above-mentioned panel again by the mode of integration;

Obtain the induction absolute capacitance values sum of these all sweep traces of panel, write down its minimum value and, described initial value is offered contact panel as initial value;

When the induction absolute capacitance values sum of described all sweep traces constantly changed, initial value was minimum induction absolute capacitance values sum all the time.

2. the method for claim 1 is characterized in that: have at least the induction absolute capacitance values of a sweep trace to fix in the induction absolute capacitance values of described all sweep traces.

3. method as claimed in claim 2 is characterized in that: the induction absolute capacitance values of article one surface sweeping line in the induction absolute capacitance values of described all sweep traces is fixed.