Background technology
Many electronic installations all use touch-screen or touch panel with existing and the position of touching in the viewing area of surveying electronic installation, generally touch by finger, hand or other conductive bodies.These electronic installations comprise mobile phone, internet apparatus, portable game machine, portable reader, music player, guider, utensil, automatic control electronic installation, kneetop computer, the television screen etc. of reaching.Touch-screen allow with the screen that shows on content displayed carry out directly alternately, rather than come indirect interaction by the touch pad of mouse or separation.Touch-screen also makes so alternately without any need for mediation device, for example the contact pilotage that must be held by the user.
More existing touch screen technologies, in these different technologies, the acoustic touch screen technology has become a kind of technology lastingly and accurately, even screen itself be dirty or be scratched the time can work.The acoustic touch screen technology relates to use will be by contact the acoustic transducer that the machinery that produced or acoustic energy convert electric signal to the physics of touch-screen.Effectively be connected to the hardware or the software subsequent analysis electric signal of described converter, to determine position contacting.Owing to can not produce acoustic energy when motionless, so the acoustics detection technology can not detect when contacting the back first and point against screen when finger or other conductive body are resisted against on the screen.
A kind of method that addresses this problem that proposes comprises along one or more edges of described touch-screen assembles a plurality of capacitors.Each capacitor comprises two electrodes that separated by air gap.Utilize object to come the surface of touch screen as finger, cause that electrode is moved toward each other, thereby reduced air gap and produced the capacitance variations surveyed that can be converted into binary signal, described binary signal is represented " maintenance " relevant with the contact of touch-screen or " release " action.Though this method makes touch-screen system can detect the Continuous Contact of object and screen, it also has many deficiencies.The first, some capacitors must be mounted to each touch-screen system or unit, a plurality of manual handle that system is changed.The second, these capacitors must be connected in series, and this has just caused complex mechanical construction.In addition, the air gap between the electrode of each capacitor is relatively more responsive to environmental baseline, and is permeated by the air particles floating easily.Further, the user must apply continuously is enough to the pressure that makes that distance between electrodes is nearer than their rest positions, to realize accurate sensing.These restrictive conditions have caused the sensing error, and have reduced the reliability of touch panel systems.
Under such background, the instruction is here proposed just.
Summary of the invention
Here disclose a kind of touch-screen system that is used for electronic installation, described electronic installation has the power supply that first voltage is provided.This touch-screen system comprises the transparency carrier of the contact that is used to receive object; Be incorporated into one or more acoustic transducer of described transparency carrier, wherein said acoustic transducer receives the acoustic wave that is produced by contact, and described acoustic wave is converted to electric signal; And be positioned at transparency conducting layer below the transparency carrier, wherein transparency conducting layer receives first voltage from power supply, and wherein the contact of object causes capacitance variations between transparency conducting layer and the object.
Touch-screen system also comprises the processor that is used to monitor electric signal and capacitance variations.In this respect, processor can be analyzed electric signal determining the position of object on transparency carrier, and can monitor capacitance variations with determine object whether with the transparency carrier Continuous Contact.
In addition, touch-screen system can comprise the storer that is used for the storage signal signature, signal mark figure represents a plurality of known location with respect to transparency carrier, wherein processor relatively comes from the electric signal of acoustic transducer and the signal signature of storage, to determine the position of object on transparency carrier.In addition, can on transparency carrier, cover Anti Glare Coatings.
Object can be a finger, and acoustic transducer can be a piezoelectric transducer.Transparency conducting layer can be indium tin oxide (ITO) layer.Object can be indirect contact with contacting of transparency carrier.
Also disclose and a kind ofly be used for determining object with respect to the existence of the transparency carrier of electronic installation and the method for position, the power supply of the pumping signal of providing is provided described electronic installation.Described method comprises, receives acoustic signal at the one or more acoustics sensors place that combines with transparency carrier, and wherein acoustic signal is produced by the touch of object to first side of transparency carrier; By the acoustics sensor, acoustic signal is converted to electric signal; Receive pumping signal at the transparency conducting layer place that combines with second side of transparency carrier, wherein object causes capacitance variations between transparency conducting layer and the object to the touch of first side of transparency carrier; Analyze capacitance variations by microcontroller, to determine whether object contacts with transparency carrier; And, analyze electric signal by microcontroller, to determine the position of object with respect to transparency carrier.
Object can be a finger, and object can be a Continuous Contact with contacting of transparency carrier.Additionally or replacedly, contact can be indirect contact.Acoustic transducer can be a piezoelectric transducer.Transparency conducting layer can be indium tin oxide (ITO) layer.
In one embodiment, analyzing electric signal can comprise: the expression of electric signal and the storage signal signature with respect to a plurality of known location of transparency carrier is compared, and determine and the corresponding matched signal of electric signal from the signal signature of storage.In another embodiment, analyzing electric signal can comprise: the expression of electric signal and the storage signal signature with respect to a plurality of known location of transparency carrier is compared; Determine one or more reference marker figure from the signal signature of storage, wherein reference marker figure is the most closely corresponding to electric signal; And with reference to reference marker figure, the operation microcontroller obtains the position of object with respect to transparency carrier with extrapolation.
Also disclose and a kind ofly be used for determining that object is with respect to the existence of the transparency carrier of electronic installation and the method for position.Described method comprises, uses the one or more acoustics sensors that combine with transparency carrier to survey by the acoustic signal of object to the touch generation of first side of transparency carrier; And, to use with one or more capacitance sensors of transparency conducting layer combination and survey the capacitance variations that produces when object contacts transparency carrier, second side of this transparency conducting layer and transparency carrier is adjacent.
Described method also comprises, capacitance variations is converted to voltage output; Acoustic signal is converted to electric signal; Use microcontroller, analytical voltage output with determine object whether with the transparency carrier Continuous Contact; And, use microcontroller, analyze electric signal to determine the position of object with respect to transparency carrier.
Object can be a finger, and Continuous Contact can be indirect contact.
Embodiment
Though embodiments of the invention are subjected to the influence of different modifications and substitute mode easily, specific embodiment is illustrated by the mode of example in the accompanying drawings, and here is described in greater detail.But, be understandable that this is not to be intended to limit the present invention in the particular forms disclosed, on the contrary, the present invention is all modifications, equivalent and the substitute mode that will cover by the embodiments of the invention of claim definition.
As discussed above, the performance aspect the position (hereinafter " location sensing ") of surveying object contact touch screen base plate of acoustic touch screen technology is outstanding, but can not whether keep Continuous Contact with substrate by object sensing usually, perhaps whether object is resisted against (hereinafter " keeping and the release sensing ") on the substrate.In order to address this problem, the dynamic surface capacitance technology is combined with the acoustics detection technology to create a touch-screen system, and it has not only realized effective maintenance and discharge sensing but also realized location sensing in ingenious design that can be manufactured according to the manufacturing process of simplifying.
Fig. 1 and 2 has shown exploded view and the front view of an embodiment of touch-screen system 1 respectively.Touch-screen system 1 comprises and the touch-screen of printed circuit board (PCB) (PCB) 4 electrical interconnections piles up 2, and printed circuit board (PCB) 4 has different electronic units, will do detailed description below.Touch-screen pile up 2 and PCB4 can be by connector 6 interconnection, connector can be any suitable electric interfaces, for example flexible print circuit (FPC).
Touch-screen piles up 2 and can be positioned on the display 21, as shown in Figure 2.Display 21 can be any in the display of several types, comprises
Display, LCOS display, other LC type of displays and/or brand, OLED display or any other suitable type of display.Display 21 can have the user and wish mutual with it effective viewing area 23.Like this because display 21 is positioned at touch-screen and piles up under 2, so touch-screen to pile up any part of effective viewing area 23 of 2 direct covering display 21 preferably transparent so that allow the user to see effective viewing area 23 by piling up 2.
Touch-screen piles up 2, one embodiment and comprises some layered element, its to the location sensing of touch-screen system 1 and maintenance and discharge one of sensing aspect or the both useful.Before below its function being described in detail, each element that touch-screen is piled up 2 embodiment carries out brief description.From top to bottom, touch-screen piles up 2 Anti Glare Coatings 8 that are included on the transparency carrier 10, and transparency carrier 10 has coboundary 13, feather edge 14, left hand edge 16 and right hand edge 18 respectively.Transparency carrier 10 can be formed by any suitable transparent material (for example comprising glass or plastics).
Touch-screen piles up 2 and also comprises transparency conducting layer 12, and in one embodiment, transparency conducting layer 12 can be positioned under the transparency carrier 10.Transparency conducting layer 12 can be that indium tin oxide (ITO) layer or it can be formed by any other suitable conductive material, as conductive polymer.
Insulator 20 (for example, para tape) is between transparency conducting layer 12 and one or more acoustic transducer 22, and described acoustic transducer 22 is along one or more edges setting of transparency carrier 10.Insulator 20 is ring texturees, effective viewing area 23 that can not hinder or block display 21 when the assembling touch-screen piles up 2.For the sake of clarity, Fig. 3 has shown that touch-screen piles up the vertical view of 2 selection layer, and the assembling touch-screen is piled up the acoustic transducer 22 that was provided with respect to the coboundary 13 and the right hand edge 18 of transparency carrier 10 at 2 o'clock is illustrated.In this embodiment, there is not acoustic transducer in feather edge 14 and the left hand edge 16 along transparency carrier 10.
Conductive trace 26 (Fig. 1 and 3) is connected acoustic transducer 22 with connector 6.Conductive trace 26 can be the conductive trace of any adequate types, for example comprises silver-colored trace.Sept 24 is positioned at and piles up 2 bottom.Just as insulator 20, sept is a ring texture, can not hinder effective viewing area 23 of display 21.Sept 24 can be any suitable material, and as flexible gasket material or seccotine stick (firm adhesive), and sept 24 can remedy irregular on the virtually any size in piling up 2 element.For example, in the embodiment shown in Fig. 1-3, conductive trace 26 and acoustic transducer 22 can have 10 to 20 microns and 0.3 to 0.5mm thickness respectively.The thickness that depends on transparency carrier 10, sept can have the thickness between 1 and 3 millimeter, in case touch-screen piles up 2 and is mounted on the display 21 like this, sept 24 can be compressed to 30 percent, so as to remedy along in the edge 13,14,16,18 of transparency carrier 10 some but be not irregular on the size that existence produced of whole acoustic transducer 22 and/or described conductive trace 26.Sept 24 can also have variable thickness, and realizes that a method of this variable thickness is exactly from four right-angle sides that separate (leg) 24a-d structure sept 24, as shown in Figure 3.
The function of touch-screen system 1, this system can be utilized touch-screen to pile up 2 top to determine to contact the position that is associated with the physics of object 28 (for example finger).Particularly, when object 28 contact touch-screens piled up 2 top, this collision produced acoustics or bending (for example machinery) ripple or the signal of propagating through Anti Glare Coatings 8, transparency carrier 10, transparency conducting layer 12 and insulator 20, and was received by acoustic transducer 22.Acoustic transducer 22 can be any other acoustic transducer of piezoelectric crystal or any suitable dimensions, shape, type and/or configuration.Though in this embodiment, acoustic transducer 22 is alignd with the coboundary 13 and the right hand edge 18 of transparency carrier 10,, as discussed above, acoustic transducer 22 can be positioned at any suitable position with respect to transparency carrier 10.
After receiving acoustic wave, acoustic transducer 22 is converted to analog electrical signal with acoustic wave, and this simulating signal is sent to PCB4 to handle from acoustic transducer 22.In this respect, can along conductive trace 26 electric signal be sent to described PCB4 by connector 6.
Fig. 4 has shown the functional block diagram of the embodiment of PCB4.In this embodiment, PCB4 comprise be used for from the external power source (not shown) for example battery receive the power supply 30 of electric energy.Power supply 30 links to each other so that the voltage of expectation form to be provided to each parts with each parts of PCB4.Illustrate for convenience, these connections are not illustrated.PCB4 comprises and is used to implement the control of touch-screen system 1 and a plurality of optional features of processing capacity, can discuss in the back, and can expect any suitable variation of these separate parts and/or component configuration.
In case electric signal is received from acoustic transducer 22, the amplifier 32 that signal can be positioned on the PCB4 amplifies.Perhaps, acoustic transducer 22 can be before sending it to PCB4 amplifying signal.Amplifying signal is passed to front-end processor 34, and it comprises analog-digital converter (A/D converter) 37.A/D converter 37 is the amplifying signal digitizing, and digitalized data is sent to microcontroller 36, and it handles digitalized data to determine that object 28 is with respect to the position of transparency carrier 10 (for example X, Y coordinate).Determine in order to carry out this position, microcontroller 36 reference-to storage 38, and will compare from acoustics sensor 22 digitalized data that receives and the data that are stored in the storer 38.The waveform or the signature of a plurality of uniquenesses of data representation of being stored, it is that the collision that takes place in the known location with respect to transparency carrier 10 in manufacture process produces.For example, Fig. 5 has shown a plurality of known point of impingement 40 with respect to transparency carrier 10
1-7At the point of impingement 40
1-7Each place contact touch-screen pile up 2 and can produce a plurality of corresponding wave label Figure 42
1-7Mark Figure 42
1-7With they corresponding X, Y position 40
1-7Be stored in the storer 38, determine for microcontroller 36 that object is contacting in using the process of touch-screen system 1 and use when touch-screen piles up the position at 2 tops.Though Fig. 5 shown and seven signature that the point of impingement is relevant only, the signature of any suitable quantity can be stored in the storer 38 (1000 points for example, 4000 points, or the like).In addition, if be not included in the data of storage corresponding to the signature of the point of impingement, microcontroller 36 can obtain this position with extrapolation and/or interpolation based on the immediate point of impingement execution algorithm in the data that are included in storage.Compare and/or calculating based on this, the X of the microcontroller 36 output points of impingement, the Y coordinate is used for controlling electronic equipment as required by the user.
Because contact or collision are the necessary conditions that produces acoustic wave that as discussed above can be analyzed, touch-screen system 1 also comprises the dynamic surface capacitance technology, when keeps piling up with touch-screen the Continuous Contact at 2 top to determine after initial contact object.In one embodiment, shown in Fig. 1 and 4, power supply 30 can be applied to aanalogvoltage (perhaps can be called pumping signal) surface of transparency conducting layer 12, and the result forms uniform electrostatic field.Therefore, when conductive body 28 (for example finger) contact touch-screen piles up 2 top, can between object 28 and transparency conducting layer 12, measurable capacitance variations be arranged.In this respect, even power supply 30 applies the constant excitation signal to keep constant voltage on transparency conducting layer 12, voltage also can be by temporary transient cover (override) when object 28 contact touch-screens pile up 2 top, on transparency conducting layer 12, produce capacitance variations (and therefore producing change in voltage), Δ C.Perhaps, unless recognizing that capacitor generally keeps electric charge/under the situation of charge loss, when object 28 did not contact touch-screen and piles up 2, power supply 30 can be periodically and to be enough to the keeping mode of constant voltage apply pumping signal on conductive layer 12.
Object 28 and touch-screen pile up the capacitance variations Δ C that produces when 2 top contacts can be on (CDC) 44 of the electric capacity-digital quantizer on the PCB4 record, Δ C can be converted into discrete voltage levels at this.CDC44 can be any appropriate C DC, and a suitable example comprises AnalogDevices, the AD7150 capacity commutator of Inc (Ya De promise semiconductor company).Whether piling up 2 top with touch-screen from the discrete voltage levels of CDC44 output and object 28 contacts relevant.Further, discrete voltage levels is before being sent to microcontroller 36, be sent out A/D converter 37 by front-end processor 34 to do further processing, next, microcontroller 36 is carried out based on discrete voltage levels and is determined whether object 28 piles up 2 logics that contact with touch-screen.For example, can programme, be in or be lower than predetermined voltage V when discrete voltage levels determining microprocessor 36
TouchWhen (for example 3.3V) object 28 just with pile up 2 and contact, and be higher than this predetermined voltage V when discrete voltage levels
TouchThe time object 28 remove from piling up 2.
Perhaps, Δ C can be on the resistor capacitor circuit on the PCB4 (RC circuit) (not shown) record, thereby change the charge or the oscillation frequency of RC circuit.Can be passed to A/D converter 37 from the voltage of RC circuit output, its monitoring output voltage is over time to follow the trail of the oscillation frequency of RC circuit.Microcontroller 36 uses subsequently from the output of A/D converter 37 and keeps and release movement determining, or definite object 28 whether with pile up 2 and contact.
Use such dynamic surface capacitance technology in conjunction with acoustics detection technology described above, allow touch-screen system 1 can determine that not only object contact touch-screen piles up 2 position, can also determine that whether object is against piling up for 2 a period of times.This need not construct many capacitors and finish in touch-screen system 1, the many capacitors of structure can increase time, complexity and extra expense to manufacture craft in touch-screen system, and bring inaccuracy and unreliability to the maintenance and the release sensing mechanism of system.
Though described and illustrated embodiments of the invention in detail in the instructions of accompanying drawing and front, such diagram and description should be considered as example and be not restriction on the characteristic.For example, specific embodiment described above can combine with the embodiment of other descriptions, and/or otherwise arranges (for example treatment element can be carried out in proper order with other).Therefore, it should be understood that and show here and what describe only is one exemplary embodiment and modification thereof.
It is the U.S. Provisional Application No. that No.61/305695, name are called " TOUCH SCREENSYSTEM WITH ACOUSTIC AND CAPACITIVE SENSING (touch-screen system with acoustics and capacitance sensing) ", submit on February 18th, 2010 that the present invention requires application number, with its full content incorporated by reference in this.