DE102017204574A1 - Display element and device for operating the same - Google Patents

Abstract

The invention relates to a display element (100) comprising between a rear substrate (102) and a front, transparent cover material (104) an electroactive component (106) for exciting the display element (100) into a vibration and an electroluminescent component (108) Excitation of the display element (100) for lighting (110).

Description

State of the art

The invention is based on a device or a method according to the preamble of the independent claims. The subject of the present invention is also a computer program.

The DE 10 2009 006 260 A1 describes a haptic tracking remote control for a central vehicle information system.

Disclosure of the invention

Against this background, with the approach presented here, a display element, a method for operating a display element, furthermore a device which uses this method, an operating element and finally a corresponding computer program according to the main claims are presented. The measures listed in the dependent claims advantageous refinements and improvements of the independent claim device are possible.

Electroluminescence can be excited by an electric field. For this purpose, an electrically insulating phosphor can be arranged between two electrodes. The electrodes with the insulator in between form a capacitor or a capacitor. When an AC voltage is applied to the electrodes, the phosphor starts to glow.

A vibration generating component may also be excited by an electric field. For this purpose, an electrically insulating, electroactive material can be arranged between two electrodes. The electrodes with the insulator in between form a capacitor or a capacitor. When an AC voltage is applied to the electrodes, the electroactive material deforms at a frequency of the AC voltage, and oscillation results.

In a display element, the light-generating component and the vibration-generating component can be integrated. In this case, the light-generating component and the vibration-generating component can be controlled separately.

A display element is presented, which has an electroactive component between a rear-side carrier material and a front-side, transparent cover material for exciting the display element into a vibration and an electroluminescent component for exciting the display element for illumination.

A display element can be understood as part of a control element. An electroactive component may comprise an electroactive polymer and react to an applied electric field with deformation. An electroluminescent component may comprise an electroluminescent dye or an electroluminescent pigment and react to an applied electric field with a light emission.

The electroactive component may be disposed between the support material and the electroluminescent component. Thereby, the light of the electroluminescent component can shine through the transparent cover material.

The electroactive component and the electroluminescent component may be electrically contacted on the front side and rear side via electrodes. The electroactive component and the electroluminescent component may be contacted via a common electrode. By multiple use of an electrode material can be saved. Furthermore, at least one working step can be saved during manufacture.

The electroactive component may comprise at least one electroactive polymer layer. The electroactive component may comprise a plurality of superimposed polymer layers. The polymer layers can be contacted individually electrically.

The display element may comprise a pressure detection device, which is designed to image a pressure on the display element in an electrical signal. The pressure detection device can be integrated in the display element.

The pressure sensing device may comprise the or another electroactive component. For detecting the pressure, the same material as for generating the vibration may be used. Thereby, the structure of the display element can be simplified.

The pressure detection device may be arranged between the carrier material and the cover material. The pressure detection device can be protected from environmental influences.

• eine erste Spannungsquelle zum Versorgen der elektrolumineszenten Komponente;
• eine zweite Spannungsquelle zum Versorgen der elektroaktiven Komponente; und
• eine Logik zum Ansteuern der ersten Spannungsquelle und der zweiten Spannungsquelle.

Furthermore, a device for operating a display element is presented according to the approach presented here, wherein the device has the following features:

• a first voltage source for supplying the electroluminescent component;
• a second voltage source for supplying the electroactive component; and
• a logic for driving the first voltage source and the second voltage source.

The voltage sources can be AC voltage sources. The logic can be called a controller.

Furthermore, an operating element for a vehicle with a user interface is presented which has at least one display element according to the approach presented here and at least one device according to the approach presented here.

The operating element may comprise a plurality of display elements. Each of the display elements may be formed to display an icon displayable by a display of the control. Likewise, the display elements may be formed as individually controllable pixels of such a display, which together can map a graphic information. For example, the display elements can be arranged side by side in a grid. Symbols and / or graphical information can also be made tactile by the vibrations.

Thus, depending on the embodiment, a display element may cover, for example, an area of less than one square centimeter, less than one square millimeter or less than one square micrometer of an area of a display of the control. The smaller the size of a single display element, the more finely structured pictorial or haptic patterns can be represented by the plurality of display elements of the control element.

• Anlegen eines elektrischen Wechselfelds an die elektroaktive Komponente, um das Anzeigeelement zu einer Schwingung anzuregen; und
• Anlegen eines elektrischen Wechselfelds an die elektrolumineszente Komponente, um das Anzeigeelement zu beleuchten.

A method for operating a display element according to the approach presented here comprises the following steps:

• Applying an alternating electric field to the electroactive component to cause the display element to vibrate; and
• Applying an alternating electrical field to the electroluminescent component to illuminate the display element.

The alternating electric field can be applied to the electroluminescent component when a touch of the display element is detected.

This method can be implemented, for example, in software or hardware or in a mixed form of software and hardware, for example in a control unit.

Also of advantage is a computer program product or computer program with program code which can be stored on a machine-readable carrier or storage medium such as a semiconductor memory, a hard disk memory or an optical memory and for carrying out, implementing and / or controlling the steps of the method according to one of the embodiments described above is used, especially when the program product or program is executed on a computer or a device.

• 1 eine schematische Darstellung eines Anzeigeelements gemäß einem Ausführungsbeispiel;
• 2 eine Darstellung einer elektrolumineszenten Folie;
• 3 eine schematische Darstellung eines Bedienelements gemäß einem Ausführungsbeispiel;
• 4 einen Schaltplan einer Vorrichtung zum Betreiben eines Anzeigeelements gemäß einem Ausführungsbeispiel;
• Die 5 bis 16 Darstellungen eines Bedienens eines Bedienelements gemäß einem Ausführungsbeispiel;
• 17 ein Ablaufdiagramm eines Verfahrens zum Betreiben eines Anzeigeelements gemäß einem Ausführungsbeispiel; und
• 18 eine schematische Darstellung eines Bedienelements gemäß einem Ausführungsbeispiel.

Embodiments of the approach presented here are shown in the drawings and explained in more detail in the following description. It shows:

• 1 a schematic representation of a display element according to an embodiment;
• 2 a representation of an electroluminescent film;
• 3 a schematic representation of an operating element according to an embodiment;
• 4 a circuit diagram of an apparatus for operating a display element according to an embodiment;
• The 5 to 16 Representations of an operation of a control element according to an embodiment;
• 17 a flowchart of a method for operating a display element according to an embodiment; and
• 18 a schematic representation of an operating element according to an embodiment.

In the following description of favorable embodiments of the present invention, the same or similar reference numerals are used for the elements shown in the various figures and similar acting, with a repeated description of these elements is omitted.

1 shows a schematic representation of a display element 100 according to an embodiment. The display element 100 has a carrier material 102 and a transparent cover material 104 on. The cover material 1044 can be referred to as a transparent encapsulation. Between the carrier material 102 and the cover material 104 are an electroactive component 106 and a electroluminescent component 108 arranged. The carrier material 102 forms a back of the display element 100 out. The cover material 104 forms a front side or visible side of the display element 100. The electroluminescent component 108 is between the electroactive component 106 and the cover material 104 arranged. The electroactive component 106 is configured to cause the display element 100 to vibrate when an alternating electric field to the electroactive component 104 is created. The electroluminescent component 108 is designed to the display element 100 to excite light when an alternating electric field to the electroluminescent component 108 is created. The light 110 penetrates the transparent cover material 104 ,

In one embodiment, the display element 100 a pressure detection device 112. The pressure detection device 112 forms a pressure on the display element 100 for example by a finger 114 , in an electrical signal.

In other words, a printed electroluminescent surface 100 presented with haptic function.

It becomes an electroluminescent luminous surface 100 with an additional functionality, the so-called haptic functionality presented. In a surface 100 with a haptic function, vibrations are caused by an actuator 106 generated. Depending on the vibration amplitude and frequency different surfaces with different textures / roughness can be simulated.

The contact force of the surface 100 can be measured by a force measurement. Once the touch force exceeds a force level, a vibration having a particular waveform can be generated. This makes it possible to give a feeling of authenticity during the operation of a virtual button. An application example is an automotive touch display with haptic function. When the display is touched, the actuator generates 106 Vibrations.

2 shows a representation of an electroluminescent film 200 , The foil 200 essentially corresponds to the display element in 1 , In contrast, here is the electroactive component through an insulating layer 202 replaced.

Electroluminescent coatings 200 can be used to make light bodies with particularly thin layer thicknesses. Such coatings 200 may be applied to planar or curved surfaces and even to flexible plastic films. An electroluminescent luminescent film 200 is a luminous capacitor. It works as a multi-layer capacity with pigment 204 and isolation 202 as a dielectric 206 ,

A typical structure of an electroluminescent surface 200 the so-called "standard build" is in 2 shown. On a transparent polymer film layer 104, such as PET, PE, PI film 104 becomes a transparent electrode coating 208 , such as an ITO coating or PEDOT: PSS deposited.

This creates the so-called front electrode 208 , On an edge of the front electrode 208 is the front bus bar 210 applied. For the printing of the front bus bar 210, for example, silver conductive paste can be used by means of a screen printing process. The next layer is a phosphor layer 204 For example, applied by screen printing. This layer 204 is the actual light-emitting electroluminescent layer 108 , Instead of phosphorus as the illuminant, alternatively, other types of electroluminescent materials such as metallic salts may be used.

As an electrical insulating layer 202 becomes a dielectric insulating material on the phosphor layer 204 applied. For example, barium titanates can be deposited by screen printing. As back electrodes 212 For example, opaque electrode coatings such as carbon black or metallic coatings may also be used.

As encapsulation can be a last layer 102 can be applied, which may also be made of an opaque material.

It is possible to perform the entire build process in a reverse order, which is called a "reverse build". In this process, the first step on the opaque protection surface 102 the return electrode 212 is applied. The last process step is the construction by means of a transparent polymer film 104 encapsulated.

3 shows a schematic representation of an operating element 300 according to an embodiment. The operating element 300 comprises a display element 100, which substantially the display element in 1 equivalent. Furthermore, the operating element comprises 300 a device 302 for operating the display element 100 , The device 302 has a first voltage source 304 for supplying the electroluminescent component 108 of the display element 100 and a second voltage source 306 for supplying the electroactive component 106 of the display element 100 , Farther includes the device 302 a logic 308 or a controller 308 for driving the first voltage source 304 and the second voltage source 306.

The components 106 . 108 are between electrodes 208 . 212 . 310 arranged. It is between the cover material 104 or the cover layer 304 and the electroluminescent component 108 a transparent front electrode 208 arranged. Between the electroluminescent component 108 and the electroactive component 106 is an intermediate electrode 310 the electroactive component 106 arranged. The intermediate electrode 310 can be reflective for the light 110 the electroluminescent component 108 be. Between the electroactive component 106 and the carrier material 102 or the substrate 102 is a common return electrode 212 the electroactive component 106 and the electroluminescent component 108 arranged.

The first voltage source 304 is with the transparent front electrode 208 and the intermediate electrode 310 connected. The second voltage source is with the intermediate electrode 310 and the return electrode 212 connected. The transparent front electrode 208 is connected to ground here.

Between the return electrode 212 and the carrier material 102 Here is an insulator layer 312 and a sensor layer 314 arranged. The sensor layer 314 is part of the pressure detection device 112 , The pressure detection device 112 represents the electrical pressure signal 316 for the logic 308 ready.

In one embodiment, between the electroluminescent component 108 and the intermediate electrode 310 another insulating layer 318 arranged as the electroluminescent component 108 may have electrically conductive components.

In the approach presented here, the dielectric insulating layer as shown in FIG 2 is represented by an electroactive polymer layer 106 replaced. In the electroactive polymers (EAP) 106 a deformation is generated by the electric field. These deformations make the sensor surface 104 vibrated. Electroactive polymer grades such as dielectric elastomers such as silicone, polyurethane or acrylic based elastomers or piezoelectric or electrostrictive polymers such as PVDF based polymers may be used for this purpose.

The vibrations caused by the electroactive polymer layer 106 can be generated surfaces 104 imitate with different roughness and / or texture by means of the so-called friction modulation. This effect helps the operator, the active sensor surface 100 to identify. As a result, a blind operation is achieved. The touch of the surface 104 is detected by a sensor unit 112. Once the contact force exceeds a predefined level and the sensor layer 314 activated, the area can be 104 be illuminated. For the sensing also a kind of strain gauge principle (DMS) or piezoelectric or piezoresistive measuring principles can be used.

In another functional mode, oscillation only occurs after touching the sensor surface 104 triggered. This gives a certain sense of authenticity in the operation of a virtual button.

In other words, in 3 the structure of the shift system 100 shown schematically. A central controller 308 reads the force signal 316 and controls the voltage sources in accordance with the control algorithm 304 . 306 U1 and U2. An E-field is through the front and back electrodes 310 . 212 the electroactive polymer layer 106 and generated by the U2 AC voltage source 306. The frequency of the excitation is in a range which is particularly suitable for producing a haptic effect. Furthermore, the geometry of the layer system 100 and the excitation frequency can be selected so that the system can be operated in a mechanical resonance. The vibration amplitudes in the resonance can clearly exceed the amplitudes of a quasi-static operation.

An E-field is placed between the front and back electrodes 208 . 212 illumination by the U1 AC source 304 generated. The frequency of the AC voltage is in a range between 50 Hz and 4 kHz. Same reverse electrode 212 Can both for the lighting 108 as well as for the electroactive polymer layer 106 be used. The voltage amplitudes of the voltages U1 and U2 are typically in several 100 V range. So that the user in case of damage to the transparent encapsulation 104 protected by an electric shock, the front electrode is recommended 208 the lighting 108 to the earth potential.

As EAP functional material 106 For example, polyvinylidene fluoride (PVDF) and its copolymers can be used. For the electrical activation of PVDF field strengths up to 200 to 300 V / μm are necessary. To keep the control voltage low, the layer thickness of the EAP layers 106 For example, be limited to 0.5 to 2 microns. The one from the EAP layer 106 generated excitation force increases proportionally to the layer thickness. To achieve sufficient force for the haptic function, several EAP layers can be used 106 be stacked. The Gleichpolpolten electrodes are electrically connected together.

Electroactive polymer layers 106 can be used not only as an actuator, but also as a force / pressure sensor 314. In this case, the change in the capacity or the charge state of the sensor 314 detected. In a multilayer electroactive polymer layer construction, it is worth considering a layer 314 as a sensor and the remaining layers 106 to use as an actor. As a result, any additional layers for the force sizing can be omitted.

Because most electroluminescent materials 108 , For example, metallic salts, are electrically conductive, a fourth insulating layer 318 below the phosphor 108 to be ordered. As insulating material 318 In this case, materials with a high dielectric constant can be used, so that the U ₁ voltage is predominantly due to the phosphor layer 108 or luminescent layer 108 falls. Since PVDF materials usually have a rather high dielectric constant, for example up to a value of 30 to 50, can for the fourth insulating layer 318 the same material as used for the EAP layers 106. Thus, the process chain can be further simplified by using as few different materials as possible.

4 shows a circuit diagram of a device 302 for operating a display element 100 according to an embodiment. The circuit diagram forms the two voltage sources 304 . 306 and their power supply via a step-up converter 400 and a DC intermediate circuit 402 from. The two voltage sources 304 . 306 are here as ever a channel of a two-channel step-down converter 404 executed.

In other words shows 4 the circuit diagram of an embodiment of the power electronics 302. To generate the voltages U1, U2, various power electronics circuits can be used. Here, as a representative of the various circuit configurations, a two-channel up-down converter 302 is shown. By actuating the switches S5, S6, the DC voltage Uv is generated. An output voltage between 0 V and Uv can be in channel 1 with the operation of the switches S3, S4 and in channel 2 be generated with the actuation of the switches S1, S2.

The 5 to 16 show illustrations of an operation of a control element 300 according to an embodiment. The operating element 300 corresponds essentially to the operating element in 3 , By way of example, the control element 300 here has at least two different display elements 100. The display elements 100 represent two different symbols. The display elements 100 may be used as sensor surfaces due to their pressure sensing device 100 be designated. A display element 100 represents a triangle for easy distinctness. The other display element here represents a circle. The control element 300 can also be a variety of individually controllable display elements 100 exhibit. The display elements may in such a case be completely or partially independently controllable individual pixels of a display matrix. As a result, almost any symbols and / or image contents can be displayed on the operating element 300. The operating element 300 here has a curved user interface 500 on. The user interface may be, for example, a partial area of an interior of a vehicle.

A haptic feedback 502 is particularly important in vehicle technology to ensure "blind" operability of the instruments, so that the visual contact with the road is not lost when operating the instruments.

Not just touch displays 300 but any touch surfaces 300 can be provided with such a haptic function. In the center console panel of a passenger car, operator elements can be added 100 arise, arising from the surface 500 of the panel 300 do not dig out. As long as they are not operated, they also do not light up. However, there are vibrations at the operator segments 502 generated. This makes it possible to distinguish between operator segments 100 and between the passive surface segments simply by hand. As soon as the operator segments 100 are actuated, an additional visual feedback 110 is provided and the element is illuminated.

In 5 are both display elements 100 or sensor surfaces 100 unlit. The display elements 100 are thus essentially invisible or inconspicuous. The electroactive components cause the display elements 100 to vibrate 502 stimulated, which can be felt by an operator.

In 6 becomes a touch by the pressure detecting means 600 the user interface 500 in the area of one of the display elements 100 detected. The operator can thereby feel a shape of the symbol shown due to the vibrations 502.

In 7 is the triangle in response to the touch 100 by the electroluminescent component of the display element 100 full surface with light 110 illuminated.

The representation in the 8th to 10 corresponds essentially to the representation in the 5 to 7 , In contrast, the control element points 300 here per symbol two display elements 100 on. In this case, a display element 100 forms a contour 800 of the symbol while the other display element 100 represents the area of the symbol.

In one embodiment, in the initial situation, the contour 800 illuminated the sensor surface 100. It will be on the sensor segments 100 in addition vibrations 502 generated. Once the operator segments 100 be pressed, the entire sensor surface 100 additionally lit.

In 8th is the contours of symbols through display elements 100 illuminated in different colors and the contour is represented by the vibrations 502.

In 9 will be like in 6 the touch 600 sensed.

In 10 will be like in 7 the touched symbol is completely visible through the light 110 illuminated.

In the 11 to 16 are in contrast to the previous figures, the symbols superimposed on each other or overlap. As in the 8th to 10 becomes the contour 800 before recognizing the touch 600 illuminated by the pressure detection device and by vibrations 502 palpable. In response to the detection of the touch, the symbol is illuminated over the entire surface.

In one embodiment, the sensor surfaces overlap 100 , Only the contour 800 the sensor surface 100 , which is to be activated context-dependent, is illuminated and in vibration 502 brought. Once the operator segments 100 be pressed, the entire sensor surface 100 additionally lit.

In 11 is the display element 100 the contour 800 the triangular symbol illuminates and the triangular surface vibrates 502 added.

In 12 becomes the touch 600 the triangle is recognized.

In 13 becomes the display element 100 the surface of the triangle is fully illuminated.

In 14 is the display element 100 the contour 800 illuminated by the circular symbol and the circular surface in oscillation 502 added.

In 15 becomes the touch 600 of the circle recognized.

In 16 becomes the display element 100 the surface of the circle fully illuminated.

17 shows a flowchart of a method for operating a display element according to an embodiment. The method has a first step 1700 of creating and a second step 1702 of investing on. In the first step 1700 When applied, an alternating electric field is applied to the electroactive component to cause the indicator to vibrate. At the second step 1702 When applied, an alternating electric field is applied to the electroluminescent component to illuminate the display element.

18 shows a schematic representation of an operating element 300 according to an embodiment. The operating element 300 corresponds essentially to the operating element in 3 , In addition, the display element 100 here has a plurality of superimposed electroactive layers 106 with their associated electrodes 212 . 310 on. The device 302 is like that with the electrodes 212 . 310 connected, that the electroactive layers 106 are each negatively contacted on one side and are positively contacted on the other side.

If an exemplary embodiment comprises a "and / or" link between a first feature and a second feature, then this is to be read so that the embodiment according to one embodiment, both the first feature and the second feature and according to another embodiment either only first feature or only the second feature.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102009006260 A1

Claims (13)

A display element (100) comprising between a backside support material (102) and a front side transparent cover material (104) an electroactive component (106) for exciting the display element (100) into a vibration (502) and an electroluminescent component (108) for exciting of the display element (100) for lighting (110). Display element (100) according to Claim 1 in which the electroactive component (106) is arranged between the carrier material (102) and the electroluminescent component (108). A display element (100) according to one of the preceding claims, wherein the electroactive component (106) and the electroluminescent component (108) are electrically contacted on the front and rear via electrodes (208, 212, 310), wherein the electroactive component (106) and the electroluminescent component (108) via a common electrode (310) are contacted. A display element (100) according to any one of the preceding claims, wherein the electroactive component (106) comprises at least one electroactive polymer layer (106). A display element (100) according to any one of the preceding claims, comprising pressure sensing means (112) adapted to image a pressure on the display element (100) in an electrical signal (316). Display element (100) according to Claim 5 in which the pressure sensing device (112) comprises the or one further electroactive component (106). Display element (100) according to one of Claims 5 to 6 in which the pressure detecting device (112) is arranged between the carrier material (102) and the cover material (104). Apparatus (302) for operating a display element (100) according to any one of Claims 1 to 7 wherein the device (302) comprises: a first voltage source (304) for supplying the electroluminescent component (108); a second voltage source (306) for supplying the electroactive component (106); and a logic (308) for driving the first voltage source (304) and the second voltage source (306). Control element (300) for a vehicle with a user interface (500), which comprises at least one display element (100) according to one of the Claims 1 to 7 and at least one device (302) according to Claim 8 having. Method for operating a display element (100) according to one of the Claims 1 to 7 the method comprising the steps of: applying (1700) an alternating electrical field to the electroactive component (106) to excite the indicator (100) to vibrate (502); and applying (1702) an alternating electrical field to the electroluminescent component (108) to illuminate the display element (100). Method according to Claim 10 in which, in step (1702) of applying, the alternating electric field is applied to the electroluminescent component (108) when a touch (600) of the display element (100) is detected. Computer program adapted to carry out the method according to one of the preceding claims. Machine-readable storage medium on which the computer program is based Claim 12 is stored.

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