WO2001018744A1

WO2001018744A1 - Touch panel element and the use thereof

Info

Publication number: WO2001018744A1
Application number: PCT/EP2000/008601
Authority: WO
Inventors: Thomas Zenker; Michael Kettler
Original assignee: Schott Glas; Carl-Zeiss-Stiftung Trading As Schott Glas; Carl-Zeiss-Stiftung
Priority date: 1999-09-04
Filing date: 2000-09-02
Publication date: 2001-03-15
Also published as: DE19942376A1; AU6842300A; EP1208530A1

Abstract

The invention relates to a touch panel element (1) with at least one key surface (4) produced from a flexible base material pane (2) and at least one further base material pane (3). Said disks are provided with at least one electrically conductive layer (5, 6) on the surfaces facing each other. The opposite electrically conductive layers (5, 6) are spaced apart by means of a bracket (7). When pressure is exerted on the flexible base material pane (2), the electrically conductive layers (5, 6) touch in the pressure load zone which is essentially punctiform. The inventive touch panel element (1) is inter alia also designed in such a manner that at least one of the electrically conductive layers (5, 6) is subdivided into planar areas (8) (matrix elements) that may have any structure. When pressure is exerted on the flexible base material pane (2), a graded voltage, a graded current and/or a graded resistance value of the planar area (8) which is touched and thereby contacted by the respective opposite layer (5, 6) can be measured across at least one of the layers (5, 6). Said measured value is characteristic of the location of the respective planar area (8).

Description

Pressure switch element and its use

The invention relates to a pressure switching element with at least one keyboard surface formed from a flexible carrier material disc and at least one further carrier material disc, each of which has at least one electrically conductive layer on the mutually facing surfaces, the opposing electrically conductive layers being kept at a distance with the aid of a holder and the electrically conductive layers touching one another at the essentially point-specific pressure loading point when the flexible carrier material disk is loaded. The invention further relates to the use of such a pressure switching element.

Such pressure switching elements are also known as touch panels. In particular, transparent pressure switch elements are often used today as input media in the form of an attachment module in front of flat screens or television screens. In addition, touch panels can also be used as a control terminal instead of a classic keyboard without being combined with a flat screen or television screen.

Various designs of transparent touch panels are available on the market. All designs have in common that the place where the surface of the touch panel is touched by a finger or an auxiliary tool (pen or similar) is converted into electrical signals. The point of contact of the surface of the touch panel is detected on the basis of these signals. A central processing unit, which both records and evaluates the signals from the touch panel and controls the flat screen, enables particularly user-friendly computer communication.

Visible to the user and in some cases "palpable" during operation, the different touch panels have different user interfaces. Touch panels based on capacitive operating principles have a mechanically non-compliant glass surface during operation. The principle of operation is based on the fact that, due to the different dielectric of the finger or the auxiliary tool compared to the air, a change in capacitance is formed around the point of contact and the function is limited to such dielectrics only. The disadvantage here is that one Contamination around the point of contact can be mistakenly interpreted as touch. As the surface is made of thick glass (a few millimeters), capacitive displays have a high mechanical, physical and chemical resistance. Capacitive displays are therefore used, for example in communication terminals in banks, information terminals or the like.

Ultrasound touch panels, infrared touch panels and field effect touch panels are based on comparable optical or electrical principles. Here too, the surface can be made of glass. Contamination is also critical here, so that such designs are aimed at similar areas of application as capacitive panels. However, their market share is much smaller than the capacitive panels.

Resistive touch panels, on the other hand, are based on spacing a conductively coated flat carrier, the base material of which is made of glass or plastic panes a few millimeters thick, with a thin, deformable film that is also conductively coated. When the film is touched, its deformation leads to local contacting of the two opposite conductive layers. In principle there are two versions of resistive touch panels:

• Analog touch panels: The conductive layers must have a very homogeneous, locally constant surface resistance. By reading out the electrical voltage values, the location of the contact can be inferred due to the very homogeneous surface resistance.

• Digital touch panels: The electrically conductive layers of the carrier and the film are structured so that discrete flat structures are created and discrete flat areas (matrix elements) are defined by the superimposition of at least one structured layer. By touching the touch panel there is a local short circuit between the discrete structures, which means that the location of the contact in a discrete flat area can be inferred within the framework of the structure size of the structures. With an increasing number of discrete structures and thereby increased spatial resolution of the touch panel, both the manufacturing effort for the touch panel and the effort for evaluating the individual signals from the multitude of connecting paths to the discrete structures increase very strongly. The advantage of a digital touch panel over an analog touch panel is that the requirements for homogeneity and calibration of the active operating area are lower.

The resistive touch panel described in US Pat. No. 5,283,558 has elements of both an analog and a digital touch panel. Thus, the touch panel consists of a first carrier, the surface of which is provided with parallel, location-sensitive, electrically conductive strips, the strips being contacted at one end via a resistance strip. Furthermore, the touch panel consists of a second carrier, the surface of which is designed analogously to the first carrier. The surface of the first or second carrier is additionally provided with electrically conductive earthing strips, which are arranged in the immediate vicinity of the location-sensitive strips. The first and second carriers are arranged one above the other in such a way that the location-sensitive strips of the two carriers are orthogonal to one another. When a carrier is subjected to pressure, the location-sensitive strips and the grounding strip come into contact at the location of the pressure load. The resistance between the location-sensitive strips and the grounding strips depends on the location of the pressure load. The resistance strips and ground strips are each connected to analog-digital converters to determine the x and y coordinates of the pressure load point. Compared to known digital or analog touch panels, this touch panel has an extremely complex and complex structure.

Transparent plastics are used as the film material in the touch panels currently predominantly available on the market. These are kept at a distance from the carrier material by means of spacers, so that incorrect switching (touching the conductive layers) without actuation is excluded. Compared to other designs of touch panels, one advantage of resistive touch panels is that a mechanical, albeit low, mechanical deformation force has to be exerted on the film for actuation. Therefore, their sensitivity to contamination is significantly lower, which is why almost exclusively resistive touch panels are used in safety-relevant areas such as medical technology and industrial automation. A disadvantage of using plastics as film material is that the physical and chemical resistance is significantly lower than that of glass user interfaces. As a result of mechanical scratching, clouding, UV radiation or surface damage from chemicals, etc., the transparency may deteriorate. Furthermore, the surface sterilizability is restricted. Another disadvantage when using plastics is the lower thermal resistance (softening, swelling) and the strong thermal expansions compared to glass. The size of the touch panels is severely limited due to the swelling of the plastics. Such phenomena in relatively small resistive touch panels, such as those used in electronic appointment planners, are relatively simple and therefore inexpensive to control.

Novel types of resistive touch panels are being used to use a thin glass pane as the film, which has sufficient deformability at a thickness of 0.15 mm to 0.4 mm. Such a surface has the advantages of the chemical and physical resistance of glass with little risk of incorrect switching.

EP 0 546 003 B1 discloses a pressure switch element formed from a glass laminate, which is formed from a flexible thin glass pane and at least one carrier material pane, each of which has an electrically conductive layer on the mutually facing surfaces. The opposing electrically conductive layers are kept at a distance using a spacer. When the flexible thin glass layer is subjected to pressure, the electrically conductive layers touch one another at the essentially point-specific pressure load point. A pressure switch element of comparable construction is known from US 4,901,074.

The invention has for its object to find a pressure switching element that can be manufactured with reduced manufacturing effort and whose signals can be evaluated with little effort and assigned to the location of a pressure load.

This object is achieved according to the invention by a pressure switching element (1) with at least one keyboard surface (4) formed from a flexible carrier material disc (2) and at least one further carrier material disc (3), each of which has at least one electrically conductive layer (5, 6), the opposing standing electrically conductive layers (5, 6) with the aid of a holder (7)

Are kept at a distance and the electrically conductive layers (5, 6) touch when the flexible carrier material disc (2) is subjected to pressure at the essentially point-specific pressure load point. With this

Pressure switching element (1) is provided such that at least one of the electrically conductive layers (5, 6) is subdivided into flat areas (8) (matrix elements) of any structure, and that at least two flat areas (8) each have an electrically conductive one

Layer (5, 6) are contacted via electrically conductive connecting elements (9) so that the contacted flat areas (8) are part of a

Resistor network are that when applying an external voltage and / or an external

Current to a resistance network sets a graduated voltage and / or a graduated current at each area (8) of the resistance network contacted via connecting elements (9) that a graduated resistance value can be assigned to each area (8) contacted via connecting elements (9), and that when the flexible carrier material disc (2) is under pressure, the graded

Voltage, the stepped current and / or the stepped resistance value of the flat area (8) through the respective opposite layer

(5, 6) is touched and thus contacted, via at least one of the layers (5,

6) is measurable, the measured value being characteristic of the location of the respective contacted area (8).

At least the part of the electrically conductive layer (5, 6) that lies at least partially within a control panel (10) of a pressure switch element (1) according to the invention can be structured, for example, like a known digital pressure switch element - at least one of the electrically conductive layers (5, 6 6) is divided into arbitrarily structured, flat areas (8) (matrix elements). Characterized in that at least two flat areas (8) of an electrically conductive layer (5, 6) are contacted via connecting elements (9), which preferably act as voltage and / or current distributors, so that the contacted flat areas (8) are part of a resistor network, but there is no need for the large number of connecting lines of a digital pressure switching element that are necessary for each individual matrix element.

Furthermore, the evaluation of the signals (measurable voltages, currents, resistance values) can be as simple as with an analog pressure switching element be made. However, there are far lower demands on the homogeneity of the sheet resistance of the conductive layer than in known analog pressure switching elements, since when an external voltage and / or an external current is applied to a resistor network, a graduated voltage and / or a graduated current is applied to each via connecting elements (9) adjusts the flat area (8) of the resistance network and since each flat area (8) contacted via connecting elements (9) can be assigned a graded resistance value or a resistance area.

Due to the reduced number of necessary connecting lines, the lower requirements for the homogeneity of the electrically conductive layers and due to the low evaluation effort of the resulting signals, the manufacturing effort and / or material requirements for a pressure switching element according to the invention is far less than with known pressure switching elements.

When the flexible carrier material disk (2) is subjected to pressure, the stepped voltage, the stepped current and / or the stepped resistance value of the flat area (8) which is touched and thus contacted by the respectively opposite layer (5, 6) is via at least one of the Layers (5, 6) measurable. The measured value is characteristic of the location of the respective flat area (8) of a layer (5, 6). The location of the pressure load can be determined using one or more measured values.

The glass keyboard according to the invention is constructed much more simply than the touch panel described in US Pat. No. 5,283,558, in particular the grounding strips necessary for the function of the touch panel can be completely dispensed with.

Further advantageous embodiments of the invention are the subject of the dependent claims and are explained below.

When the flexible carrier material disk (2) is subjected to pressure, the stepped voltage, the stepped current and / or the stepped resistance value of the flat area (8) which is touched and thus contacted by the respectively opposite layer (5, 6) is preferably at least one the layers (5, 6) by means of an analog-digital converter measurable, the analog-digital converter translating the respective measured values into digital positions.

The measured values (signals) are transmitted via at least one analog-to-digital converter, preferably as part of at least one analog controller, to the location of the flat area (8) which is touched by the respective opposite layer (5, 6) and thus contacted. and ultimately assigned to the location of the pressure load point. In addition to the analog measurement process, the analog controller also has the task of controlling the sequence of at least one measurement process to uniquely determine the location of the pressure load point. This is generally carried out by activating the pressure switching element (1) with a voltage or current source, in the case of several activations, via changing connection points (11) of the pressure switching element (1). Furthermore, the analog controller has the task of transmitting the measurement information (signals) to a control unit.

At least two flat areas (8) are contacted via connecting elements (9) in series and / or parallel connection, so that the contacted flat areas (8) are part of a resistance network. The connecting elements (9) preferably act as voltage and / or current distributors and form together with the contacted flat areas

(8) a resistor network.

The connecting elements (9) and / or the flat areas (8) are preferably electrical resistors or they have an electrical resistance value. The connecting elements particularly preferably have

(9) and / or the flat areas (8) have an electrical sheet resistance

The connecting elements (9) are likewise preferred or have resistance bridges, the connecting elements (9) preferably being or having electronic resistance components and / or sheet resistors, in particular thin-film and / or thick-film resistors.

In a further preferred embodiment of the pressure switching element (1), the connecting elements (9) are arranged on the pressure switching element (1), in particular on the flexible carrier material disc (2) and / or the carrier material disc (3), the connecting elements (9) being particularly preferred the electrically conductive layer (5, 6) are structured. The structuring or subdivision of the connecting elements (9) and / or the flat areas (8) into a network can be carried out, for example, by means of ablative methods, in particular by structuring the electrically conductive layer (5, 6) with a laser beam or by means of photolithographic structuring of the electrically conductive Layer (5, 6) take place.

It is also possible to produce the flat areas (8) and / or the connecting elements (9) by means of application methods, in particular by means of brushing, spraying, printing or sputtering methods.

Application and removal processes can also be used in combination.

The flat areas (8) are preferably structured in the form of strips, rings and / or ring segments, the flat areas (8) are preferably aligned with one another in a selected coordinate direction of a selected coordinate system (e.g. polar coordinates, Cartesian coordinates).

The flat areas (8) of the layers (5, 6) are particularly preferably structured in the form of parallel strips, the strips of the layer (5) preferably being arranged orthogonally to the strips of the layer (6) and thus a cartesian coordinate system ( x, y coordinates).

Depending on the preferred construction of the pressure switching element (1), certain flat areas (8) are not contacted via connecting elements (9). These areas (8) are electrically inactive and can, for example, take over the function of pure separation areas.

The flat areas (8) are preferably at least partially within an operating field (10) of the pressure switching element (1).

The pressure switching element (1) preferably has at least two connection points or connection points (11) for the voltage and / or power supply of one or more resistance networks. If, for example, there is a resistance network on the flexible carrier material disc (2) and another resistance network on the carrier material disc (3), each electrically conductive layer (5, 6) can have two connection points (11). However, there may also be a connection point (11) on the layer (5) of the flexible carrier material disc (2) and the other connection point (11) on the layer (6) of the carrier material disc (3). The application of an external voltage and / or an external current to a resistance network when the flexible carrier material disc (2) is under pressure and a graduated voltage and / or a graduated current occur at each flat area (8) contacted via connecting elements (9) Resistor network sets. At the same time, the stepped voltage, the stepped current and / or the stepped resistance value of the flat area (8) which is touched by the respectively opposite layer (5, 6) and thus contacted, can be measured via at least one of the layers (5, 6) ,

Overall, the electrically conductive layers (5, 6) have at least two connection points (11) for applying an external voltage and / or an external current to at least one resistance network.

The stepped voltage, the stepped current and / or the stepped resistance value of the flat area (8) which is touched by the respectively opposite layer (5, 6) and thus contacted, is preferably via the connection points (11) and / or via at least an additional contact point (13) of the layers (5, 6) can be measured. If there are at least two connection points (11) on each layer (5, 6), there is at least one contact point (13) on the opposite layer (5, 6).

At least one resistance network is preferably located on the flexible carrier material disc (2) and / or the carrier material disc (3) and or at least one resistance network is localized on the flexible carrier material disc (2) and the carrier material disc (3) and when the flexible carrier material disc (2) is loaded under pressure. touched by the opposite layer (5, 6) and thus completely contacted.

In a further embodiment of the invention, the flexible carrier material pane (2) is a thin glass pane, the carrier material pane (3) is a glass pane and / or the electrically conductive layer (5, 6) is a transparent, electrically conductive layer, in particular an ITO layer, an Fe ₂ layer O ₃ - or an SnO ₂ layer. The pressure switching element (1) is preferably a glass keyboard.

The pressure switching element (1) according to the invention is preferably used to operate, control, regulate and / or control essentially electrically operated devices and / or devices, in particular from the fields of household, domestic technology, banks, services, e-commerce, multimedia, consumer electronics, Telecommunications, medicine, fitness, leisure, traffic, industry, science and measurement technology.

In conjunction with a monitor, in particular a flat-screen monitor, an essentially transparent pressure switch element (1) according to the invention is preferably used for the operation, control, regulation and / or control of essentially electrically operated devices and / or devices, in particular from the fields of household and domestic technology , Banking, services, e-commerce, multimedia, consumer electronics, telecommunications, medicine, fitness, leisure, transport, industry, science and measurement technology.

The described use of the pressure switch element (1) according to the invention is particularly aimed at the combination of a transparent pressure switch element (1) with a display element, for example a background image or a flat screen (TFT (Thin Film Transistor), STN (Super Twisted Neumatic), LCD (Liquid Cristal Display ), Pale (Plasma Addressed Liquid Display), PDP (Plasma Display Panel), EL (Electro Luminescence)). A combination with a television screen is also possible if it is a so-called Fiat panel. This type of television screen has recently come onto the market. Compared to classic television screens, they have a flat instead of a classic curved front.

The surface of a screen can also serve as a carrier material disc (3) of the pressure switching element (1), which among other things. a particularly compact and integrated design allows.

Characterized in that the user interface of the pressure switch element (1) is preferably formed from a thin glass pane or the pressure switch element (1) is even a glass keyboard, there are further advantages for the use of the invention, such as. B. easy and simple cleaning and sterilizability and thereby improved hygiene, high scratch resistance, high Resistance to a large number of chemicals as well as solvents and cleaning agents, high transparency and UV resistance, very good tightness, in particular to liquids and gases, and high temperature resistance.

A pressure switching element (1) according to the invention, in particular if the pressure switching element (1) is a glass keyboard, is preferably integrated in the electrically operable device or the device or is arranged on or on such a device, the pressure switching element being particularly preferably in a viewing window of the electrically operable Device is integrated or arranged on or on such a viewing window.

A pressure switch element (1) according to the invention, in particular a transparent pressure switch element (for example the glass keyboard) and particularly preferably in connection with a display element, is at least integrated in at least part of a household appliance, in particular in a door, in a viewing window or in an operating panel. is arranged on or on such a door, a viewing window or a control panel. As a result, in particular the space provided for an original operating unit can be saved or used in some other way. This type of arrangement also gives rise to additional design options. For example, a pressure switching element according to the invention for operating a microwave device or an oven can be integrated directly into the microwave device door or into the oven door. The space for the operating elements originally arranged on the lateral front edge area of the appliances can thus either be omitted, the appliances can be made correspondingly more compact, or the space freed up can be used, for example, as an additional cooking space.

In a further advantageous embodiment of the invention it is provided that a corresponding pressure switch element forms the viewing door or the viewing window of a household appliance or is arranged on or on a viewing door or a viewing window in such a way that this is completely overlaid. Preferably, only a part of the pressure switching element is deposited with a display element, so that the original function of the viewing door or the viewing window is retained. This type of arrangement additionally creates a particularly homogeneous overall impression of the household appliance. Exemplary embodiments of the invention are explained in more detail below with reference to the drawings.

Show it:

Fig. 1: A pressure switching element according to the invention in cross section.

2a: A flexible carrier material disk made of thin glass of a pressure switching element according to the invention with structuring of the electrically conductive layer in supervision and an enlarged detail of the structured connecting elements and flat areas.

2b: A glass carrier material disk of a pressure switching element according to the invention with structuring of the electrically conductive layer in supervision.

2c: An arrangement of the flexible carrier material disc according to FIG. 2a and the carrier material disc according to FIG. 2b of a pressure switching element according to the invention with structuring of the electrically conductive layers in supervision.

Fig. 2d: An equivalent circuit diagram with electrical resistances of the structuring according to Fig. 2a or 2b. The connection points A, B and the connection points C, - C _n between the resistors can be found in the structures of FIGS. 2a and 2b.

Fig. 2e: equivalent circuit diagram for two structured support glass panes one above the other (see Fig. 2c), which are indicated by a double arrow conductively connected via a pressure load point.

2f: equivalent circuit diagram for a voltage measurement process according to FIG. 2e via two connection points A and B for applying an electrical voltage or a current and an additional connection point D.

2g: equivalent circuit diagram for a voltage or current measurement process according to FIG. 2e via two connection points A and D. 3a: A carrier material disk made of glass or flexible thin glass of a pressure switching element according to the invention with structuring of the electrically conductive layer in a flat area (strip) arranged parallel to one another, the strips being contacted at their two ends via strip-shaped connecting elements. According to FIGS. 2a-c, a pressure switch element contains at least one such structured layer.

3b: An equivalent circuit diagram with electrical resistances of the structure according to Fig. 3a. The connection points A, B, B 'and the connection points C, - C _n between the resistors can be found in the structures of FIG. 3a. The connection points B and B 'are externally electrically connected in this exemplary embodiment.

3c: equivalent circuit diagram for two structured glass panes one above the other according to FIG. 3a, which are indicated by a double arrow at a pressure load point (contact point).

Fig. 3d: equivalent circuit diagram for a voltage measurement process according to Fig. 3c in the event that the resistors R _AC1 and R _ACr and R _CkCI and R _Ck . _{cr have} the same value. An electrical voltage or a current is applied via two connection points A and B and the measurement is carried out via an additional connection point D.

Fig. 3e: equivalent circuit diagram for a voltage measurement process as in Fig. 3d but for the case that the resistors R _AC1 and R _Acr and R _Ckα and R _{Ck α} . do not have the same value.

3f: equivalent circuit diagram for a voltage or current measurement process according to FIG. 3c via two connection points A and D.

4a: An embodiment of a structuring of an electrically conductive layer of a glass or flexible thin glass carrier material of a pressure switching element according to the invention, which already defines flat pressure switching areas (matrix elements) preferably on a carrier material disc.

4b: an equivalent circuit diagram with electrical resistances of the structure according to FIG. 4a. The connection points A, B, C, D and the connection points E _k , between the resistors can be found in the structures of FIG. 4a.

4c: equivalent circuit diagram for a structured layer of a carrier glass pane according to FIG. 4a, which is indicated by a double arrow and is conductively connected via a pressure loading point (contact point) to a preferably unstructured second pane which is provided with an additional connection point F.

4d: Equivalent circuit diagram for a voltage measurement process according to FIG. 4c via the two connection points A and B for applying an electrical voltage or a current and the additional connection point F.

4e: equivalent circuit diagram for a voltage or current measurement process according to FIG. 4c via two connection points A and F.

Example 1:

The pressure switch element (1) according to the invention shown in FIG. 1 consists of an upper, flexible thin glass pane (2) formed keyboard surface (4) and a lower, relatively thick carrier material pane (3) made of glass. The two panes (2, 3) each have a transparent, electrically conductive ITO layer (5, 6) on the mutually facing surfaces, the opposing electrically conductive layers (5, 6) with the aid of a holder (7) Are kept at a distance and the electrically conductive layers (5, 6) touch when the flexible thin glass pane (2) is subjected to pressure at the essentially point-specific pressure load point.

The electrically conductive layers (5, 6) are divided into flat areas (8) (strip-shaped matrix elements), and the flat areas (8) each of an electrically conductive layer (5, 6) are connected via electrically conductive connecting elements (not shown) act as a voltage and / or current distributor, contacted, so that the contacted flat areas (8) are part of a resistance network.

When an external voltage and / or an external current is applied to a resistance network, a graduated voltage and / or is established a graduated current at each area (8) of the resistance network contacted via connecting elements (9).

A graded resistance value can be assigned to each flat area (8) contacted via connecting elements (9).

When the flexible thin glass pane (2) is subjected to pressure, the stepped voltage, the stepped current and / or the stepped resistance value of the flat area (8) which is touched and thus contacted by the respectively opposite layer (5, 6) is via at least one of the Layers (5, 6) can be measured, the measured value being characteristic of the location of the respective flat area (8).

Fig. 2a shows the flexible thin glass pane (2), Fig. 2b shows the carrier glass pane (3) and the respective structuring of the electrically conductive layer (5, 6) in flat areas (8), connecting elements (9), supply line connections (12) and Junction points (11).

In this exemplary embodiment, the structuring was carried out by means of a laser beam, the electrically conductive layer (5, 6) along the thin dividing lines being completely removed. With other production methods, the structuring can also be produced with two or more alternating layers which have different surface resistances.

The electrically conductive layer (5, 6) is divided within the control panel (10) of the pressure switching element (1) into flat areas (8) (strip-shaped matrix elements) arranged parallel to one another.

The flat areas (8) are each connected at their one narrow end via connecting elements (9), which are also structured from the electrically conductive layer (5, 6), so that the connected flat areas (8) are connected in series. The connection points between the flat areas (8) and the connection elements (9) are the narrow, conductive openings in the dividing line at the points C to C ₂₉ in FIG. 2a and C to C ₃₆ in FIG. 2b. The resistance value of a connection element results from the distance between the connection points C- and C _{i + 1} , the width of the connection element (9) and the surface resistance of the conductive layer (5, 6). The connecting elements (9) are contacted in Fig. 2a and 2b via supply connections (12) and two connection points (11) (connection points A, B) for voltage and / or power supply, whereby when an external voltage or an external current is applied the connection points (11) set graduated measurable voltages and / or currents of the individual flat areas (8).

With a surface resistance R _Q of approximately 20 Ω / _{Q of} the respective electrically conductive layer (5, 6), in this exemplary embodiment there is a connection resistance of approximately 900 for the electrically conductive layer (6) (FIG. 2b) between the connection points (11) Ω. 495 Ω are allotted to the flat areas (8) and to the connecting elements (9) via which the flat areas (8) are in contact with one another, and 455 Ω to the supply line connections (12) between the connecting elements (9) and the connection points (11) , so that the active analog evaluation range with 495 Ω is limited to about 52% of the connected value. An alternative embodiment is the use of highly conductive printed bus connections between the connecting elements (9) and the connection area (11), so that the evaluation area is increased to almost 100%.

Analog controllers on the market can generally process resistors of the order mentioned, so that the glass keyboard (1) can be connected to such controllers without further modification.

2c shows the flexible thin glass pane (2) according to FIG. 2a and the carrier glass pane (3) according to FIG. 2b lying one above the other. The flat areas (8) (matrix elements) of one layer (5) are arranged orthogonally to those of the other layer (6) and thus brought together to form an overall matrix. For example, the flat area of the layer (5) represents the x-coordinate and the flat area (8) of the layer (6) the y-coordinate of the total matrix, the size of the resulting square area essentially the resolution of the pressure switch element (1) certainly.

When the flexible thin glass pane (2) is subjected to pressure, the stepped voltage, the stepped current and / or the stepped resistance value of the flat area (8), which touches through the respective opposite flat area (8) of the layer (5, 6) and thus contacts is about at least one of the layers (5, 6) can be measured, the measured value being characteristic of the location of the respective flat area (8). Knowing the graded voltages, currents and / or resistance values of the contacting flat areas (8), the location of the pressure load point (contact point) is clearly determined.

The respective measured values (signals) are evaluated by an analog-digital converter in the analog controller.

An equivalent circuit diagram made up of electrical resistors for the structures of the electrically conductive layers in FIGS. 2a and 2b is shown in FIG. 2d. The individual connection points A, B and the connection points C to C _{n (n} = _{29 or 36)} are marked in FIGS. 2a and 2b. The connecting elements form a linear resistor network between C, and C _n (horizontal resistors). The flat areas each represent a resistor that is only contacted on one side (vertical resistors).

2e shows a switching and voltage measurement process (with pressure load). The switching point in a matrix element is indicated by the curved double arrow in which the switching contact between the two opposite flat areas is made. One of the conductive layers is activated via the connection points A and B with an electrical voltage source, so that the resistance chain (series connection) of the connecting elements works as a voltage divider. An analog-to-digital converter for voltage measurement is connected via the other opposite conductive layer via an additional connection point D (this can also be a connection point A, B of this layer, for example) and used as a measurement sensor. The location of the flat area contacted under pressure loading can be inferred from the graduated measured value. The simplified equivalent circuit diagram is shown in Fig. 2f. The resistance between C ₁ and D (R _C1D ) is irrelevant for the measuring process, since a voltmeter always works with a high-resistance input resistance (R,), which will be very large compared to R _C1D . The measurable voltage value is set between the connection points A to B via the resistance chain alone. At least two measuring processes are always necessary, in which a voltage (current) source is created between different connection points A - D in order to determine a clear two-dimensional contact position (pressure load point). A measurement process is indicated in FIG. 2g, in which a voltage (current) source is applied between the two conductive layers between the connection points A and D via the contact point (pressure load point) and the associated current (voltage) value and / or Resistance value is measured via the resistor chain A - D. If the resistance C, - D is always smaller than a connection resistance between C, and C, ₊₁ , then the flat areas can always be assigned a graded current (voltage) value and / or resistance value. At least two measuring processes are always necessary, in which a voltage (current) source is created between different connection points A - D in order to determine a clear two-dimensional contact position.

Example 2:

In an alternative embodiment, according to the invention, as in exemplary embodiment 1, a carrier disk (3) and a flexible thin glass pane (2) are used, one of the panes being provided with a structured electrically conductive layer (5, 6), for example similar to the embodiment in FIG. 2a (flat areas (8)), and the other pane is preferably provided with an unstructured electrically conductive layer (5, 6) with a connection point D. The measuring process is illustrated in FIG. 2g, a voltage (current) source being applied between the two conductive layers (5, 6) between the connection points A and D via the contact point and the associated current (voltage) value and / or resistance value can be measured via the resistance chain A - D. If the resistance C, - D is always less than a connection resistance between C, and C _{l + 1} and, in addition, the resistance between the contact point and the connection point D on the preferably unstructured disc is always very small compared to the resistance of the flat area between it Connection point and the most distant end from this, the flat areas can always be assigned a current (voltage) area and / or a resistance area which is different from those of the other flat areas and uniquely identifies a flat area in a graded manner , In addition, the orthogonal coordinate of the contact position in this area can be determined in a continuous, non-graded manner via the current (voltage) value and / or resistance value, which is within the limits of the current (voltage) range and / or resistance range of the flat area. The current (voltage ) value and / or resistance value will be greater, the further the contact point is from the connection point to the connection element. In this way, a two-dimensional printing position can be determined by combining a structured layer and a preferably unstructured layer with a single measuring operation, in a graduated manner in a coordinate and in a continuous manner in the coordinate orthogonal to it. The measuring process does not require switching the voltage (current) source between two connection pairs and can be carried out in a simplified manner with a single analog measurement. A special application would be the implementation of a single or a group of at least two sliders.

Example 3:

The structuring of one of the conductive layers (5, 6) of a pressure switching element (1) according to the invention, as described in exemplary embodiment 1, is carried out according to FIG. 3a. The flat areas (8) are contacted at both ends with connecting elements (9). The structuring of the second conductive layer (5, 6) is preferably arranged orthogonally to it in accordance with exemplary embodiment 1. The equivalent circuit diagram of this structuring is shown in Fig. 3b. The connection points B and B 'are preferably at the same potential and are connected externally.

3c shows a switching and voltage measuring process. The switching point in a matrix element is indicated by the curved double arrow, in which the switching contact between the two opposite flat areas is made. One of the conductive layers is activated via the connection points A and B with an electrical voltage source, so that the resistance chain of the connecting elements works as a voltage divider. An analog-to-digital converter for voltage measurement is connected via the other, opposite conductive layer via an additional connection point D and used as a measuring sensor. Is the two-row resistor network symmetrical, so that at the points C, and C, 'the same electrical potential U _Cl = U _Cl . sets, then the simplified equivalent circuit diagram is shown with Fig. 3d. The resistance between 0.0 / and D (R _C1D ) is irrelevant for the high-resistance voltage measurement. The measured voltage value is only set via the resistance chain A - B. At least two measuring processes are always necessary, in which a voltage (current) ) source is created to determine a clear two-dimensional contact position.

Example 4:

In this example, one of the conductive layers is structured similar to a layer in exemplary embodiment 3 and the other layer is preferably unstructured. Furthermore, the resistance network of the structured side is constructed asymmetrically in such a way that the voltage potentials when the network is activated in ascending or descending order according to C _{1 t} C, C ₂ , C ₂ ', ..., C _n , C _n ' to adjust. A voltage measurement across the connection point D of the preferably unstructured disk is illustrated in FIG. 3e. Non-overlapping voltage ranges are formed in the individual flat areas C ,, .. C _π . With a single analog voltage measurement, the two-dimensional coordinate of the printing position can be clearly determined, in such a way that the flat areas can be assigned graded voltage ranges and the orthogonal position in a flat area can be assigned via the non-graduated voltage value within the associated voltage range. In this way, a two-dimensional printing position can be determined by combining a structured layer and a preferably unstructured layer with a single measuring operation, in a graduated manner in a coordinate and in a continuous manner in the coordinate orthogonal to it.

Example 5:

The pressure switching element is constructed as in exemplary embodiment 4. On the other hand, a voltage (current) source is created between the connection points A and D via the contact point (pressure load point). A representation of the measuring process is explained in Fig. 3f. The current (voltage) measurement and / or resistance measurement via the resistance network A - D allows a clear assignment of the area when the resistance between the contact point and the connection point due to different pressure positions is no more than the resistance value of a connecting element C, - C _{l + 1} fluctuates. At least two measurements over different connection points A - C and D are necessary for a two-dimensional position determination. If, in addition, the fluctuations in the resistance between the contact point and the connection point are negligibly small compared to the partial resistance value of a connecting element CC _{i + 1} corresponding to the required resolution, the two-dimensional position can be clearly determined. In this way, a combination of a structured disc and a preferably unstructured disc can be used to determine a two-dimensional printing position with a single measuring process, in a graduated manner in a coordinate and in a continuous manner in the coordinate orthogonal to it.

Example 6:

The structuring of one of the conductive layers (5, 6) of a pressure switching element (1) according to the invention, as described in exemplary embodiment 1, is carried out according to FIG. 4a. In this example, the structuring takes place in individual flat, here square areas (8) which already have a complete two-dimensional matrix structure. Adjacent flat areas (8) are connected by connecting elements (9) which are designed as structured channels, from the shape of which their preferably identical resistance values result. The structure has four connection points A - D, which are preferably located opposite one another in pairs. The resistance of a connecting element (9) results from its width, length and the sheet resistance of the conductive layer (5, 6). The other opposite conductive layer (5, 6) is preferably unstructured and has at least one connection point F.

The equivalent circuit diagram of the structured layer (5, 6) is shown in FIG. 4b, and a voltage measurement is explained in FIG. 4c. An electrical voltage and / or a current is applied between two of the connection points A - D and the voltage value within the resistance network at the contact point is evaluated analogously via the measuring contact F via the contact point.

The circuit diagram of the measuring process is further reduced to the resistance circuit shown in FIG. 4d, the resistance between points A (B) and E _{23 being} the total resistance which arises between these points in the network. Then at least two measuring processes with different connection points A - D and F are necessary in order to clearly determine the printing position. Example 7:

The pressure switching element is constructed as in exemplary embodiment 6, but is activated via one of the connection points (A - D) on the structured disk and the connection point F on the preferably unstructured disk with a voltage (current) source (FIG. 4e). The resistance R _FEkl between F and E _kl is preferably small compared to the difference between any two resistance _chains R _FEkl and R _FEmn . If F is now congruent with connection point B on the other carrier disk, then the lines A - F form an axis of symmetry on the structure according to FIG. 4a-c and pressure contacts on the points E _k and E, _k provide the same current ( Voltage) measured value and / or resistance value. Then at least two measuring processes with different connection points A - D and F are necessary in order to clearly determine the printing position.

Example 8:

The design is as described under working examples 7, but in contrast the connection point F is preferably congruent with connection point C or D or another point, so that a line AF does not form an axis of symmetry on the resistor network according to FIGS. If, in addition, the resistance R _FEk , between F and E _{kl is} small compared to the difference between any two resistance _chains R _FEk , and R _FEmn , then a single analog current (voltage) measurement and / or resistance measurement is sufficient under these conditions, to uniquely determine a printing position E _w . In this way, the two-dimensional coordinate of a printing position can be determined in a graded and unambiguous manner by a single current (voltage) measurement and / or resistance measurement. LIST OF REFERENCE NUMBERS

1 pressure switch element

2 flexible carrier material discs

3 carrier material disc

4 keyboard surface

5, 6 electrically conductive layer

7 bracket

8 flat areas

9 connecting elements

10 control panel

11 connection points or points

12 supply connections

Claims

PATENT CLAIMS

1. Pressure switch element (1) with at least one keyboard surface (4) formed from a flexible carrier material disc (2) and at least one further carrier material disc (3), each of which has at least one electrically conductive layer (5, 6) on the mutually facing surfaces, wherein the opposing electrically conductive layers (5, 6) are kept at a distance with the aid of a holder (7) and the electrically conductive layers (5, 6) touch one another at the essentially point-specific pressure load point when the flexible carrier material disc (2) is subjected to pressure; characterized in that at least one of the electrically conductive layers (5, 6) is divided into flat areas (8) (matrix elements) of any structure,

that at least two flat areas (8) of an electrically conductive layer (5, 6) are contacted via electrically conductive connecting elements (9), so that the contacted flat areas (8) are part of a resistance network,

that when an external voltage and / or an external current is applied to a resistance network, a graduated voltage and / or a graduated current occur at each flat area (8) of the resistance network contacted via connecting elements (9),

that a graded resistance value can be assigned to each flat area (8) contacted via connecting elements (9), and

that when the flexible carrier material disc (2) is subjected to pressure, the stepped voltage, the stepped current and / or the stepped resistance value of the flat area (8) which is touched and thus contacted by the respectively opposite layer (5, 6) via at least one of the Layers (5, 6) can be measured, the measured value is characteristic of the location of the respective contacted area (8).

2. Pressure switching element according to claim 1, characterized in that the stepped voltage, the stepped current and / or the stepped resistance value can be measured by means of an analog-to-digital converter, the analog-to-digital converter translating the respective measured values into digital positions.

3. Pressure switching element according to claim 1 or 2, characterized in that at least two planar areas (8) each have an electrically conductive layer (5, 6) via connecting elements (9) in series and / or parallel connection.

4. Pressure switching element according to at least one of claims 1 to 3, characterized in that the connecting elements (9) and / or the flat areas (8) are electrical resistances or have an electrical resistance value.

5. Pressure switching element according to at least one of claims 1 to 4, characterized in that the connecting elements (9) and / or the flat areas (8) have an electrical surface resistance.

6. Pressure switching element according to at least one of claims 1 to 5, characterized in that the connecting elements (9) are or have electrical resistance components.

7. Pressure switching element according to at least one of claims 1 to 6, characterized in that the connecting elements (9) are sheet resistors, in particular thin-film and / or thick-film resistors.

8. Pressure switching element according to at least one of claims 1 to 7, characterized in that the connecting elements (9) are arranged on the pressure switching element (1), in particular on the flexible carrier material disc (2) and / or the carrier material disc (3).

9. Pressure switching element according to at least one of claims 1 to 8, characterized in that the connecting elements (9) from the electrically conductive layer (5, 6) are structured.

10. Pressure switch element according to at least one of claims 1 to 9, characterized in that the flat areas (8) and / or the connecting elements (9) by means of ablative methods, in particular by structuring the electrically conductive layer (5, 6) with a laser beam or by means of photolithographic structuring of the electrically conductive layer (5, 6).

11. Pressure switching element according to at least one of claims 1 to 10, characterized in that the flat areas (8) and / or the connecting elements (9) by means of application methods, in particular by means of brushing, spraying, printing or sputtering methods, applied are.

12. Pressure switching element according to at least one of claims 1 to 11, characterized in that the flat areas (8) are structured in the form of strips, rings, ring segments and / or any shape.

13. Pressure switch element according to at least one of claims 1 to 12, characterized in that the flat areas (8) are preferably aligned with one another in a selected coordinate direction.

14. Pressure switch element according to at least one of claims 1 to 13, characterized in that the flat areas (8) are at least partially within an operating panel (10) of the pressure switch element (1).

15. Pressure switch element according to at least one of claims 1 to 14, characterized in that the electrically conductive layers (5, 6) have a total of at least two connection points (11) for applying an external voltage and / or an external current to at least one resistance network.

16. Pressure switching element according to at least one of claims 1 to 15, characterized in that the stepped voltage, the stepped current and / or the stepped resistance value of the flat area (8) which touches through the opposite layer (5, 6) and thus is contacted, can be measured via the connection points (11) and / or via at least one additional connection point of the layers (5, 6).

17. Pressure switch element according to claim 16, characterized in that at least two connection points (11) are on one layer (5, 6) and at least one additional connection point on the opposite layer (5, 6).

18. Pressure switching element according to at least one of claims 1 to 17, characterized in that at least one resistance network is located on the flexible carrier material disc (2) and / or the carrier material disc (3).

19. Pressure switching element according to at least one of claims 1 to 18, characterized in that at least one resistance network is located on the flexible carrier material disc (2) and the carrier material disc (3) and when the flexible carrier material disc (2) is subjected to pressure loading by the respectively opposite layer (5, 6) touched and thus fully contacted.

20. Pressure switching element according to at least one of claims 1 to 19, characterized in that the flexible carrier material disc (2) is a thin glass disc.

21. Pressure switch element according to at least one of claims 1 to 20, characterized in that the carrier material disc (3) is a glass disc.

22. Pressure switch element according to at least one of claims 1 to 21, characterized in that the electrically conductive layer (5, 6) is a transparent, electrically conductive layer, in particular an ITO, Fe ₂ 0 ₃ or SnO ₂ layer.

23. Use of a pressure switching element (1) according to at least one of claims 1 to 22, for the operation, control, regulation and / or control of essentially electrically operated devices and / or devices, in particular from the fields of household, house technology, banks, services, E-commerce, multimedia, consumer electronics, telecommunications, medicine, fitness, leisure, traffic, industry, science and measurement technology.

24. Use of a pressure switching element (1) according to at least one of claims 1 to 22, in connection with a monitor, in particular a flat screen monitor, for the operation, control, regulation and / or control of essentially electrically operated devices and / or devices, in particular from the areas of household, house technology, banking, service, e-commerce, multimedia, consumer electronics, telecommunications, medicine, fitness, leisure, traffic, industry, science and measurement technology.