CN104202031A - Method for improving precision and accuracy of capacitive touch key - Google Patents

Abstract

The invention provides a method for improving the precision and the accuracy of a capacitive touch key. The method comprises the following specific steps of: step 1), a resistor is added to the transmission path of the touch key, thus the various noise signals are attenuated to amplitudes which cannot be identified after passing through the resistor, so as to improve the identification precision, a resistor with a resistance of 1k to 3k is added to the transmission path at the rear end of the touch key, and because the amplitude of an interference signal is low, the amplitude is greatly attenuated and cannot be wrongly identified after passing through the resistor; step 2) in order to solve the problem of nonadjustable sensitivity or too high sensitivity of the touch key, a capacitor is connected aside the key in parallel, after the capacitor is added, a total capacitance of the touch area of the touch key to the ground is equivalently increased, when the key is touched by a finger, the generated capacitance change is certain, and if the total capacitance is increased, that is, a change ratio is reduced, the problem of too high sensitivity of key touch identification is solved, and when a certain distance exists between the finger and the key or the finger incidentally slides through the surface of the key, the operations of the key cannot be triggered.

Description

A kind of method that improves capacitance touch button precision and accuracy

Technical field

The present invention relates to the capacitance touch button design of notebook computer, desktop computer and panel computer.The present invention proposes a kind of method that improves touch key-press touch recognition precision and accuracy, improve button antijamming capability and the ability of avoiding misoperation, specifically a kind of method that improves capacitance touch button precision and accuracy.

Background technology

Touch key-press is because of its good waterproof and dampproof property, better simply structural design and there is no the features such as mechanical key access times age limit, and the factor such as attractive in appearance, frivolous is used in a large number comprising on the electronic product of computer in addition.But because of features such as touch key-press reliability are not high, and general approach is unstable, in special-purpose fields such as special computers, rarely has application.The present invention proposes for the field that application has demand to focus on again touch recognition precision and accuracy simultaneously to touch key-press just.

Summary of the invention

The object of this invention is to provide a kind of method that improves capacitance touch button precision and accuracy.

The object of the invention is to realize in the following manner, concrete steps are as follows:

Step 1) increases a resistor on touch key-press transmission path, make various noise signals after this resistance, decay to the amplitude that can not be identified, to improve accuracy of identification, on the transmission path of touch key-press rear end, increase a 1k to the resistor between 3k, because of interference signal amplitude less, after this resistor, amplitude significantly decays, and can not identified by mistake

Step 2) for the sensitivity of solution touch key-press is non-adjustable or the too high problem of sensitivity, at the other shunt capacitor of button, increase after this capacitor, be equivalent to increase the total capacitance of touch key-press touch area to ground, when finger touch button, the electric capacitance change producing is certain, and total capacitance has increased, i.e. variation ratio has reduced, this has just solved the too high problem of button touch recognition sensitivity, when finger is while also having certain distance apart from button or when finger slips over from keytop unintentionally, button operation can not be triggered;

For different situations, choose the capacitor that capacitance is different, to reach touch recognition sensitivity adjustable effect, according to electric capacity, increase the principle that variation ratio reduces, choose capacitor capacitance larger, sensitivity is lower, choose capacitor capacitance less, sensitivity is higher, experimental verification, choosing 5p is advisable to capacitance between 60p, in conjunction with notebook structural member situation, consider keytop thickness of insulating layer, capacitor capacitance selects 20p left and right more applicable.

Object beneficial effect of the present invention is: a kind of method that improves touch key-press touch recognition precision and accuracy of the present invention, can improve button antijamming capability and the ability of avoiding misoperation.

Accompanying drawing explanation

Fig. 1 is circuit diagram;

Fig. 2 is workflow diagram.

Embodiment

With reference to Figure of description, a kind of method that improves capacitance touch button precision and accuracy of the present invention is described in detail below.

A kind of method that improves capacitance touch button precision and accuracy of the present invention, non-adjustable in order to solve touch key-press sensitivity, the common too high problem of sensitivity, the other shunt capacitor method of button is proposed in circuit design, increase after this capacitor, be equivalent to increase the total capacitance of touch key-press touch area to ground, when finger waits conductor touch key-press, the electric capacitance change producing is certain, and total capacitance has increased, i.e. variation ratio has reduced, this has just solved the too high problem of button touch recognition sensitivity, when finger also has certain distance apart from button or when finger slips over from keytop unintentionally, button operation can not be triggered.

For different situations, choose the capacitor that capacitance is different, thereby reach touch recognition sensitivity adjustable effect.According to above-mentioned electric capacity, increase the principle that variation ratio reduces, choose capacitor capacitance larger, sensitivity is lower, chooses capacitor capacitance less, and sensitivity is higher.Experimental verification, conventionally chooses 5p and is advisable to capacitance between 60p.In conjunction with general notebook structural member situation, consider keytop thickness of insulating layer, capacitor capacitance selects 20p left and right more applicable.

On touch key-press transmission path, increase a resistor, make various noise signals after this resistance, decay to the amplitude that can not be identified.Traditional design method reduces transmission path impedance as far as possible, can improve accuracy of identification like this, but often brings precision too high, and various interference signals are easy to be identified as the problem of touch signal by mistake.This method proposes on the transmission path of touch key-press rear end, to increase a 1k to the resistor between 3k, and because interference signal amplitude is less, after this resistor, amplitude significantly decays, and can not identified by mistake.General notebook computer can be chosen 1.8k resistance resistors and use.

Except the technical characterictic described in specification, be the known technology of those skilled in the art.

Claims (1)

1. improve a method for capacitance touch button precision and accuracy, it is characterized in that concrete steps are as follows:

Step 1) increases a resistor on touch key-press transmission path, make various noise signals after this resistance, decay to the amplitude that can not be identified, to improve accuracy of identification, on the transmission path of touch key-press rear end, increase a 1k to the resistor between 3k, because of interference signal amplitude less, after this resistor, amplitude significantly decays, and can not identified by mistake

Step 2) for the sensitivity of solution touch key-press is non-adjustable or the too high problem of sensitivity, at the other shunt capacitor of button, increase after this capacitor, be equivalent to increase the total capacitance of touch key-press touch area to ground, when finger touch button, the electric capacitance change producing is certain, and total capacitance has increased, i.e. variation ratio has reduced, this has just solved the too high problem of button touch recognition sensitivity, when finger is while also having certain distance apart from button or when finger slips over from keytop unintentionally, button operation can not be triggered;

For different situations, choose the capacitor that capacitance is different, to reach touch recognition sensitivity adjustable effect, according to electric capacity, increase the principle that variation ratio reduces, choose capacitor capacitance larger, sensitivity is lower, choose capacitor capacitance less, sensitivity is higher, experimental verification, choosing 5p is advisable to capacitance between 60p, in conjunction with notebook structural member situation, consider keytop thickness of insulating layer, capacitor capacitance selects 20p left and right more applicable.