DE102015100859A1 - Method for operating a display device and display device - Google Patents

Abstract

In various embodiments, a method for operating a display device (10) is provided. The display device has a plurality of pixels (12), which each have at least one light-emitting component. In the method, actual states of the light-emitting components are determined during operation of the display device (10). The actual states of the light emitting devices are compared with predetermined states of the respective light emitting devices. If the comparison shows that an actual state of a first light emitting device (24) of the light emitting devices is deteriorated from the predetermined state of the first light emitting device (24), at least one second light emitting device (26) of the light emitting devices is driven so that the deteriorated actual state of the first light emitting device (24) by means of the second light emitting device (26) is compensated. The second light-emitting device (26) is disposed adjacent to the first light-emitting device (24) and configured to emit light of the same emission color as the first light-emitting device (24) in the predetermined state.

Description

The invention relates to a method for operating a display device and a display device.

Modern display devices often have pixels arranged in rows and columns each having one, two, three or four sub-pixels. For example, the sub-pixels are configured to emit red, green, blue, or white light in operation depending on image data for displaying an image. Alternatively, the subpixels can only produce white light, which is then converted into red, green or blue light by means of a color filter. Each sub-pixel has a light-emitting component, for example an inorganic light-emitting component (LED) or an organic light-emitting component (OLED), for emitting the light. A display device with OLEDs can be referred to, for example, as an organic display device or as an organic display. The display device can be used for example as a visual display in a mobile phone, a tablet PC, a laptop, a monitor or a television.

Both the LEDs and the OLEDs may spontaneously fail and be subject to wear, thereby degrading their condition. In OLEDs spontaneous failure is also referred to as "sudden death". In addition, OLEDs can cause so-called "bright spots" through particles which, during operation of the OLED, can lead to increased wear and accelerated aging leading to the failure of the OLED, in the case of display devices these failure mechanisms lead to the pixel failure and the reproduction quality of the OLED corresponding display device is adversely affected by this.

A reduction in the brightness of individual pixels and / or a shift of the original color location in the operation of the corresponding pixels due to aging and / or wear can be compensated, for example, by using an increased drive voltage and / or an increased drive current at the corresponding pixels. However, the increased drive voltage and / or the increased drive current can further accelerate wear and aging. In addition, as the resolution increases, the drive voltages and drive currents also increase, which further decreases the lifetime of the individual pixels and thus of the display device. For example, as the resolution increases, the fill factor, ie the ratio of active area to non-active area, decreases, which is compensated by an increasing drive voltage and / or an increasing drive current and, associated therewith, a higher brightness of the individual pixels. However, the life is an important quality feature of a display device, especially in a television.

In general, in display devices after their manufacture, a final inspection is performed in which such errors can be detected in part early, so that the corresponding display devices, in which the pixel errors are already recognizable, can be sorted out before delivery. Subsequent errors occurring, such as the abovementioned spontaneous failures or accelerated wear and / or aging processes can not be reliably excluded with the help of the final inspection.

Alternatively, the exposure of the individual pixels may be reduced and thus the lifetime extended by increasing the pixel areas of the pixels and matching the pixel areas of the individual pixels to their individual lifetimes, typically pixels emitting light of different colors. is different, done.

An object of the invention is to provide a method of operating a display device that contributes to the display device having a high fault tolerance and / or lifetime.

An object of the invention is to provide a display device having a high fault tolerance and / or lifetime.

An object of the invention is achieved in one aspect by a method of operating a display device. The display device has a plurality of pixels, which each have at least one light-emitting component. During operation of the display device, actual states of the light-emitting components are determined. The actual states of the light emitting devices are compared with predetermined states of the respective light emitting devices. If the comparison shows that an actual state of a first one of the light emitting devices is deteriorated from the predetermined state of the first light emitting device, at least a second one of the light emitting devices is driven such that the deteriorated actual state of the first light emitting device is compensated by the second light emitting device becomes. The second light-emitting component is arranged adjacent to the first light-emitting component. The second light emitting device is configured to receive light the same emission color emitted as the first light-emitting device in the predetermined state.

Determining the state of the first light-emitting device and compensating for the possibly deteriorated state of the first light-emitting device cause the display device to be operated without or at least only with negligibly lower display and / or image quality despite the poor state of the first light-emitting device. As a result, the display device has a high fault tolerance and / or a long service life. In particular, a pixel or subpixel failure or wear and / or aging of the pixel or subpixel can be compensated for by means of adjacent pixels or subpixels. For example, a luminance of adjacent pixels or subpixels can be increased in order to outshine the failed, worn and / or aged pixel. Clearly, the color aging or the spontaneous failure of one of the light-emitting components can thus be detected by means of an integrated sensor and compensated for by corresponding operation of the neighboring pixels.

The display device can thus be operated at the beginning of the lifetime with the highest resolution, with all the pixels glowing with normal luminance. In the case of a pixel or subpixel failure, neighboring pixels, in particular subpixels of the neighboring pixels, of the failed pixel are driven correspondingly more strongly in order to compensate for the missing brightness.

For example, the actual state of one of the light emitting devices may be representative of the degree of wear, the degree of aging, the brightness in operation, and / or the color rendering, such as color aging, in operation of the corresponding light emitting device. The actual state may also be representative of a total failure of the corresponding light emitting device. In contrast, the predetermined state is the desired state that the light-emitting device has in consideration of an acceptable level of wear or aging of acceptable loss of brightness in operation and / or acceptable color rendering, such as acceptable color aging, in operation of the corresponding light-emitting device. The desired state may differ from the actual state at the time of completion and / or delivery of the display device. For example, the predetermined state may be within a predetermined range of acceptable states. The predetermined state or the range of acceptable states can be determined empirically, for example, and stored on a memory unit of the display device.

The fact that the second light-emitting component emits light of the same or at least approximate color as the first light-emitting component may mean, for example, that the respective centroid wavelengths of the light deviate from each other by a maximum of 5 to 20 nm, for example by a maximum of 10 nm.

In a further development, the actual states of the light-emitting components are determined by detecting actual values of a parameter that is representative of the actual states of the light-emitting components. The actual states are compared with the predetermined states by comparing the detected actual values of the parameter with predetermined target values of the parameter which are representative of the predetermined states of the respective light emitting devices. The detection of the actual values of the parameter, which is representative of the actual states of the light-emitting components, makes it possible in a simple manner to determine the states of the light-emitting components.

In a development, the deteriorated actual state of the first light-emitting component is compensated by means of the second light-emitting component by changing a desired value of a drive variable of the second light-emitting component, depending on the deteriorated actual state of the first light-emitting component. The compensation by means of the change in the target value of the drive quantity makes it possible in a simple manner to compensate for the poor state of the first light-emitting component by means of the second light-emitting component. The desired value of the control variable is changed in particular depending on the actual value of the parameter. If, for example, the actual value of the parameter deviates greatly from the desired value of the parameter, then the desired value of the control variable can be greatly changed. In contrast, if the actual value of the parameter differs only slightly from the desired value of the parameter, then the target value of the control variable can only be changed slightly. The target values of the drive amount of the light-emitting devices depend on image data supplied to the display device for displaying an image and / or aging of the display device.

In a further development, the actual states are actual brightnesses of the light-emitting components, and the given states are predetermined brightnesses light-emitting components. In other words, the parameter is representative of the brightness. For example, the parameter is the brightness. In particular, the actual value of the parameter is an actual value of the brightness and the desired value of the parameter is a desired value of the brightness. The actual value of the brightness can be detected, for example, if the state of the first light-emitting component is detected by means of a photosensitive sensor unit. Alternatively, the brightness representative parameter may be a voltage applied to the light-emitting device in operation, a current flowing across the light-emitting device in operation, or an electrical resistance of the light-emitting device.

In a development, the deteriorated actual state of the first light-emitting component is compensated by means of the second light-emitting component by increasing a brightness of the second light-emitting component. For example, the drive quantity has an effect on the brightness. This can easily contribute to compensate for the poor condition of the first light-emitting device.

In a development, the drive variable is an operating voltage and / or an operating current for operating the second light-emitting component. To compensate for the poor actual state of the first light-emitting device, the voltage value of the operating voltage and the current value of the operating current are increased. This can easily contribute to compensate for the poor condition of the first light-emitting device. The voltage value and / or the current value depend on the image data for displaying the image.

In a further development, the control of the pixels is dependent on the image data that is representative of the image to be displayed by means of the display device. The drive of the second light-emitting component to compensate for the poor actual state of the first light-emitting component is dependent on the image data. The image data is representative of image information. Clearly, in the case of a subpixel failure in the display device, differently colored neighboring subpixels are purposefully differently controlled as a function of the image information which is to be displayed in the affected and the surrounding pixels. As a result, the failure of the subpixel can be compensated in the best possible way and the corresponding subpixel can be "outshone" in the best possible way.

In a development, if the first light-emitting component is not operated on the basis of the current image data, the second light-emitting component is not triggered to compensate for the poor actual state of the first light-emitting component. This contributes to the fact that an image to be displayed due to the compensation is not distorted or deteriorated. If, for example, a red light-emitting component, which is also referred to below as a red subpixel, fails and due to the image data in the area of the failed red subpixel, a blue image is currently displayed, for which the red subpixel would not be operated even in perfect condition Thus, no corresponding adjacent red subpixel is activated and / or driven to compensate for the failed red subpixel. Otherwise, the blue picture would get a red print.

In a further development, if the image to be displayed as a function of the image data has a color gradient in the region of the first and second light-emitting component, the second light-emitting component is selected as a function of the color gradient among all light-emitting components which are arranged adjacent to the first light-emitting component and Emit light of the same emission color as the first light-emitting device in the predetermined state. To compensate for the poor state of the first light-emitting component, basically one, two or more adjacent light-emitting components can be selected as the second light-emitting component, provided that they emit light of the same emission color. Which of the adjacent light-emitting components is selected as the second light-emitting component can be decided depending on the image data, in particular depending on the color gradient. For example, if the image to be displayed transitions from left to right blue, represented by blue subpixels, to magenta represented by blue and red subpixels, to white represented by blue, red, and green subpixels, in the event of failure, one of the red subpixels in the Magenta-colored area, only the neighboring subpixels of the failed red subpixel are used for its compensation, which are arranged from the failed subpixel not in the direction of the blue area, so that in the blue area no red pixel lights. This allows a clean color edge to be displayed when transitioning from blue to red.

In a development, two or more second light-emitting components are controlled to compensate for the poor actual state of the first light-emitting component. For example, in line and / or Column direction, the two, three or four next-adjacent light-emitting devices that emit light of the same emission color, as the first light-emitting device, are controlled to compensate for the poor state of the first light-emitting device.

In a further development, the light-emitting components are arranged in rows and columns. The second light-emitting device is the light-emitting device closest to the first light-emitting device in the row direction or in the column direction, which emits light of the same emission color as the first light-emitting device in the predetermined state.

In a further development, the light-emitting components are arranged in rows and columns. If the comparison shows that the actual state of the first light-emitting device is deteriorated from the predetermined state of the first light-emitting device, at least a third of the light-emitting devices is driven so as to compensate for the deteriorated actual state of the first light-emitting device by the third light-emitting device is arranged, wherein the third light emitting device is arranged so that the second light emitting device between the first and the third light emitting device is arranged, and is adapted to emit light of the same emission color, as the first light emitting device in the predetermined state.

In a further development, the light-emitting components are organic light-emitting components. In order to determine the actual state of one of the organic light-emitting components, the corresponding organic light-emitting component is deactivated, and after deactivating the organic light-emitting component, a voltage value of a voltage is detected which is applied to the organic light-emitting component. The actual state of the corresponding organic light-emitting component is determined as a function of the detected voltage value. Generally speaking, the detection of a total failure of a pixel can be done by tracking the voltage at the pixel required for operation with a particular current by the pixel driver. This allows, for example, the detection of a spontaneous short circuit of the pixel.

An object of the invention is achieved in one aspect by a display device. The display device comprising: a plurality of pixels each having at least one light-emitting device; a sensor device coupled to the organic light emitting devices and configured to detect actual states of the light emitting devices during operation of the display device; an evaluation unit coupled to the sensor device and configured to compare the detected actual states of the light emitting devices with predetermined states of the respective light emitting devices; and a control unit that is coupled to the evaluation unit and the organic light-emitting devices and that is designed, if the comparison shows that an actual state of a first of the light-emitting devices against the predetermined state of the first light-emitting device is deteriorated, at least a second one of the light-emitting devices is driven so as to compensate for the deteriorated actual state of the first light-emitting device by the second light-emitting device, the second light-emitting device being adjacent to the first light-emitting device and emitting light of the same emission color as the first light-emitting device in the default state.

For determining the states of the light-emitting components, these are electrically coupled to a sensor device. The sensor device may comprise one, two or more sensor units coupled to the pixels. For example, each light-emitting component can be assigned exactly one sensor unit. For example, the sensor units can be arranged directly adjacent to the light-emitting components with which they are associated. The coupling of the sensor device, in particular of the sensor units, with the light-emitting components may, for example, be an electrical coupling, by means of which a value of an electrical voltage which is applied to the light-emitting component, or a value of an electrical current which flows via the light-emitting component, can be determined. However, the coupling may also be an optical coupling, wherein the sensor units are photosensitive and detect the light emitted by the light emitting devices to which they are associated.

The driver unit is used for operating, driving, controlling and / or regulating the light-emitting components. The driver unit may also be referred to as a control and / or regulating unit. The driver unit may comprise an integrated circuit or be part of an integrated circuit. For example, the driver unit and the sensor device may be parts of the same integrated circuit.

In a further development, the light-emitting components are organic light-emitting components.

Embodiments of the invention are illustrated in the figures and are explained in more detail below.

Show it:

1 a plan view of an embodiment of a display device in a first state;

2 a plan view of the display device according to 1 in a second state;

3 a plan view of the display device according to 1 in a third state;

4 a plan view of the display device according to 1 in a fourth state;

5 a plan view of the display device according to 4 in the fourth state;

6 a plan view of the display device according to 1 in a fifth state;

7 a plan view of the display device according to 6 in the fifth state;

8th a plan view of the display device according to 1 in a sixth state;

9 a plan view of the display device according to 8th in the sixth state;

10 a flowchart of an embodiment of a method for operating a display device;

11 a flowchart of an embodiment of a method for operating a display device;

12 a flowchart of an embodiment of a method for monitoring a state of a light-emitting device.

In the following detailed description, reference is made to the accompanying drawings, which form a part of this specification, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. Because components of embodiments may be positioned in a number of different orientations, the directional terminology is illustrative and is in no way limiting. It should be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention. It should be understood that the features of the various embodiments described herein may be combined with each other unless specifically stated otherwise. The following detailed description is therefore not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims. In the figures, identical or similar elements are provided with identical reference numerals, as appropriate.

A light emitting device may be a semiconductor light emitting device in various embodiments and / or formed as a light emitting diode, an organic light emitting diode, a light emitting transistor, or an organic light emitting transistor. The light may, for example, be light in the visible range, UV light and / or infrared light. In this connection, the light-emitting component can be designed, for example, as a light-emitting diode (LED) as an organic light-emitting diode (OLED), as a light-emitting transistor or as an organic light-emitting transistor. The light emitting device may be part of an integrated circuit in various embodiments. Furthermore, a plurality of light-emitting components may be provided, for example housed in a common housing.

1 shows a plan view of an embodiment of a display device 10 , in particular to a pixel arrangement of the display device 10 in a first condition. The display device 10 has a plurality of pixels 12 and at least one sensor device. In the first state of the display device 10 are all pixels 12 in good condition. The pixels 12 are arranged in rows and columns. In particular shows 1 three lines and three columns of pixels 12 , The entire display device 10 may have a far greater number of rows and columns, for example between 100 and 10,000 rows and between 100 and 10,000 columns. The pixels 12 a row are arranged side by side in the corresponding row and directly adjacent to each other. The display device 10 is a display of a mobile phone, a tablet PC or a laptop, a monitor or a TV. The display device 10 can be an organic display device 10 be.

Each of the pixels 12 has a blue light emitting device 18 , a red light emitting component 20 and a green light emitting device 22 , The pixels 12 can be referred to as RGB pixels in this context. The light-emitting components 18 . 20 . 22 are juxtaposed in the row direction and directly adjacent to each other. In addition, each of the pixels 12 not shown electronic components, such as transistors, capacitors, diodes and / or electrical lines have. The light-emitting components 18 . 20 . 22 may be inorganic or organic light emitting devices 18 . 20 . 22 be.

The pixels 12 , in particular the light-emitting components 18 . 20 are formed on a common carrier, not shown. The carrier may be translucent or transparent. The carrier serves as a carrier element for electronic elements or layers. The support may include, for example, plastic, metal, glass, quartz and / or a semiconductor material or be formed therefrom. Furthermore, the carrier may comprise or be formed from a plastic film or a laminate with one or more plastic films. The carrier may be mechanically rigid or mechanically flexible.

If the light emitting devices 18 . 20 . 22 organic light-emitting components, they each have an organic functional layer structure. The organic functional layer structure may, for example, have one, two or more partial layers. By way of example, the organic functional layer structure may comprise a hole injection layer, a hole transport layer, an emitter layer, an electron transport layer and / or an electron injection layer. The hole injection layer serves to reduce the band gap between the first electrode and hole transport layer. In the hole transport layer, the hole conductivity is larger than the electron conductivity. The hole transport layer serves to transport the holes. In the electron transport layer, the electron conductivity is larger than the hole conductivity. The electron transport layer serves to transport the holes. The electron injection layer serves to reduce the band gap between the second electrode and the electron transport layer. Furthermore, the organic functional layer structure may have one, two or more functional layer structure units which each have the sub-layers and / or further intermediate layers.

The organic functional layer structures are arranged between non-illustrated electrodes and emit light in operation if an operating voltage is applied to them. The light-emitting components 18 . 20 . 22 can be encapsulated by means of an encapsulation layer, not shown. The encapsulation layer forms a barrier to chemical contaminants or atmospheric agents, in particular to water (moisture) and oxygen. The encapsulation layer may be formed as a single layer, a layer stack or a layer structure. The encapsulation layer may include or be formed from: alumina, zinc oxide, zirconia, titania, hafnia, tantalum lanthania, silica, silicon nitride, silicon oxynitride, indium tin oxide, indium zinc oxide, aluminum doped zinc oxide, silicon carbide, poly (p-phenylene terephthalamide), nylon 66, and the like Mixtures and alloys thereof.

The sensor device has a plurality of sensor units 16 on. The sensor device and / or the sensor units 16 can be formed on the carrier. The sensor units 16 are arranged in rows and columns. In particular shows 1 three rows and nine columns of sensor units 16 , Each sensor unit 16 is one of the light emitting devices 18 . 20 . 22 assigned and electrically connected to the corresponding light emitting device 18 . 20 . 22 connected. The sensor units 16 are designed so that with their help, an electrical voltage to the corresponding light-emitting device 18 . 20 . 22 is applied, an electric current, via the corresponding light-emitting device 18 . 20 . 22 flows, and / or an electrical resistance of the corresponding light emitting device 18 . 20 . 22 can be detected.

During operation of the display device 10 can the pixels 12 and in particular the light-emitting components 18 . 20 . 22 be driven with a driver unit, not shown, that by means of the display device 10 one, two or more images, in particular a sequence of images, such as a movie, a video or a video game are visually displayed. The driver unit may be formed on the carrier. The driver unit, not shown, has an electronic circuit. The driver unit has, in particular, an operating time control, not shown, a data driver unit and a gate driver unit, by means of which the pixels 12 , in particular the light-emitting components 18 . 20 . 22 can be controlled depending on displayed image data. To drive the pixels 12 the driver unit changes setpoint values of at least one control variable by means of which the pixels 12 be controlled. The target values of the control variable depend on the image data. The image data contain the image information for the images to be displayed and can be entered, for example, by means of an internal or external arithmetic unit. Depending on the control of the pixels 12 By means of the driver unit and the corresponding image data, the light-emitting components emit 18 . 20 . 22 Light in the different colors, where by means of color mixing of the generated light more colors can be displayed.

The sensor units 16 monitor during operation the states of the light emitting devices 18 . 20 . 22 to which they are assigned. The states are, for example, an operation in general and / or a brightness, in particular an intensity, a color impression, in particular a color location, and / or wavelength ranges of the light-emitting components 18 . 20 . 22 emitted light in particular. The states can be monitored, for example, by means of the sensor units 16 Actual values of parameters of the corresponding light-emitting components 18 . 20 . 22 and compared to one or more corresponding thresholds. The parameters are, for example, the electrical voltage at the corresponding light-emitting component 18 . 20 . 22 is applied, the electric current through the corresponding light-emitting device 18 . 20 . 22 flows, and / or the electrical resistance of the corresponding light emitting device 18 . 20 . 22 ,

If the display device 10 is new, the actual values of the parameter correspond to setpoint values of the parameter. The setpoint values of the parameter depend on the actual values of the control variable. To put it plainly, one of the light-emitting components is intended for a given control, which is given by the actual value of the control variable 18 . 20 . 22 react with a desired reaction, which is represented by the actual value of the parameter. With increasing age and / or wear, the actual values of the parameters change with control with a predetermined desired value of the control variable. If the actual values of the parameter at the given control are equal to or even exceed a threshold, or if a difference between one of the actual values of the parameter and a corresponding target value of the parameter equals or even exceeds the threshold, then the state of the corresponding light emitting device 18 . 20 . 22 classified as bad.

Alternatively to the in 1 shown embodiment, fewer sensor units 16 be arranged, the plurality of light emitting devices 18 . 20 . 22 are assigned and monitor them. For example, a sensor device with only one sensor unit 16 be arranged with all the light-emitting components 18 . 20 . 22 is electrically connected and monitors. Furthermore, the sensor units 16 be photosensitive elements and that of the corresponding light emitting devices 18 . 20 . 22 detect emitted light and so the corresponding OLEDs 18 . 20 . 22 monitor. In this case, the electrical coupling between the sensor units 16 and the light-emitting devices 18 . 20 . 22 be waived. For example, the sensor units 16 each have an organic functional layer structure as photosensitive elements. Optionally, such an organic functional layer structure may for example be the same or at least similar to the organic functional layer structures of the light-emitting components 18 . 20 . 22 ,

Furthermore, every pixel 12 have yet another light emitting device, for example, a light emitting device that emits white light and which can also be referred to as a white light emitting device. The pixels 12 can then be called RGBW pixels. Alternatively, the display device 10 pixel 12 with only one light-emitting component, for example with one white light-emitting component or with three exclusive white light-emitting components, and with controllable color filters by means of which the white light of the light-emitting components can be converted into colored light.

2 shows a plan view of the embodiment of the display device 10 according to 1 in a second state, wherein in particular one of the light-emitting components 18 . 20 . 22 is in bad shape. In particular, the red light emitting device 20 the middle pixel 12 in the middle column in bad condition and is subsequently used as the first light emitting device 24 designated. The first light-emitting component 24 in bad condition may be completely failed or shine with reduced brightness or intensity or emit light with a different color impression, for example with a changed color location, in particular altered wavelength ranges.

The bad state of the first light-emitting device 24 is by means of the associated sensor unit 16 detected. In particular, the corresponding sensor unit detects 16 an actual value of a parameter of the first light emitting device 24 representative of the state of the first light-emitting device 24 is. The actual value of the parameter is forwarded to an evaluation unit, not shown, or retrieved from this. The evaluation unit compares the actual value of the parameter with a desired value of the parameter and / or the predetermined threshold value. If a difference between the actual value of the parameter and the target value of the parameter is equal to or even exceeds a predetermined threshold, the state of the first light emitting device 24 classified as bad.

To compensate for the poor condition of the first light-emitting device 24 is a drive at least one of the first light-emitting device 24 adjacent red light emitting devices 20 changed. For example, in 2 the right, left, above and / or below the first light emitting device 24 lying red light emitting device 20 to compensate for the bad condition. The light emitting device 18 . 20 . 22 that compensates for a bad condition of another of the light-emitting devices 18 . 20 . 22 is used and to this in the row or column direction, the nearest light-emitting device 18 . 20 . 22 is, is used as the second light-emitting device 26 designated.

If the first light-emitting device 24 has failed in bad condition, the second light-emitting device 26 be operated with significantly increased performance compared to its normal operation. If the first light-emitting device 24 is reduced only in its performance in a poor state, the second light-emitting device can be operated with such a high power that the reduced performance of the first light-emitting device 24 is being compensated. Overall, such a high display quality of the display device 10 be ensured.

Alternatively to the red light emitting device 20 In bad condition could also be one of the blue light emitting devices 18 or one of the green light emitting devices 22 to be in bad condition and as the first light emitting device 24 be designated. Optionally, as the second light-emitting component 26 to compensate for the poor condition of the first light-emitting device 24 a component emitting to the corresponding blue light 18 adjacent blue light emitting device 18 or a component emitting to the corresponding green light 22 adjacent green light emitting device 22 to be selected.

3 shows a plan view of an embodiment of the display device 10 according to 1 in a third state, in which the red light emitting device 20 of the left pixel 12 in the middle line is in poor condition and is the first light-emitting device 24 referred to as.

To compensate for the poor condition of the first light-emitting device 24 may be one, two or more of the closest in the row or column direction of red light emitting devices 20 which are then used as second light-emitting components 26 be designated. In addition, one, two or more further red light-emitting components may be used 20 to compensate for the poor condition of the first light-emitting device 24 which are farther from the first light-emitting device 24 are removed as the second light emitting devices 26 , Optionally, these red light emitting devices 20 as third light-emitting components 28 be designated. For example, according to 3 the next in the row direction red light emitting device 20 as the third light emitting device 28 used. Alternatively or additionally, the diagonal direction of the display device 10 nearest red light emitting devices 20 as third light-emitting components 28 used.

Alternatively to the red light emitting device 20 In bad condition could also be one of the blue light emitting devices 18 or one of the green light emitting devices 22 to be in bad condition and as the first light emitting device 24 be designated. Optionally, as the third light-emitting component 28 to compensate for the poor condition of the first light-emitting device 24 a component emitting to the corresponding blue light 18 next blue light emitting device 18 or a component emitting to the corresponding green light 22 next green light emitting device 22 to be selected.

4 shows a plan view of the display device 10 according to 1 in a fourth state. In the fourth state, the pixels become 12 controlled so that by means of the display device 10 , At least with the illustrated pixel arrangement, a red image is displayed.

The representation of the red image is dependent on image data, that of the display device 10 are supplied and containing the image information, such that in the region of the pixel arrangement shown an exclusively red image is displayed.

Alternatively, by means of the display device 10 Depending on the image data, a green or a blue image may be displayed.

5 shows a plan view of the display device 10 according to 4 in the fourth state, wherein the individual light-emitting components 18 . 20 . 22 the display device 10 are shown. So that the display device 10 the red image represents only the red light emitting devices 20 activated. Since that in 5 middle red light emitting device 20 in the bad state, that is the first light-emitting device 24 can be designated compensate for the adjacent red light-emitting devices 20 used as second light emitting devices 24 may be referred to, the poor state of the first light-emitting device 24 , All other light emitting devices 18 . 20 . 22 can remain deactivated due to the representation of the exclusively red picture. Thus, the compensation of the bad state of the first light-emitting device is performed 24 depending on the image data.

6 shows a plan view of the display device 10 according to 1 in a fifth state, where one column of pixels 12 is shown more. In the fifth state, the pixels become 12 controlled so that by means of the display device 10 , at least with the pixel arrangement shown, a blue portion of an image in the left column, a magenta portion in the middle three columns, and a white portion of an image in the right column. The color transition from blue to magenta to white can be called a color gradient.

The representation of the image with the color gradient is dependent on the image data, that of the display device 10 are supplied and containing the image information, such that in the region of the pixel arrangement shown, an image is generated with the displayed color gradient.

Alternatively, by means of the display device 10 Depending on the image data, an image with a different color gradient can be displayed.

7 shows a plan view of the display device 10 according to 6 in the fifth state, wherein the individual light emitting devices 18 . 20 . 22 the display device 10 are shown. So that the display device 10 the image with the color gradient represents only the red light emitting devices 20 the left column not activated and the others already. In addition, only in the right column, the green light emitting devices 22 activated. Since that in 7 middle red light emitting device 20 in the bad state, that is the first light-emitting device 24 can be referred to compensate for this in the column direction above and below adjacent and in the row direction right adjacent red light emitting devices 20 used as second light emitting devices 24 may be referred to, the poor state of the first light-emitting device 24 , The left in the row direction to the first light-emitting device 24 adjacent red light emitting device 20 are not used for compensation, so that the blue color impression in the illustrated left column of the display device 10 is not distorted. Thus, the compensation of the bad state of the first light-emitting device is performed 24 depending on the image data, in particular so as not to falsify the color impression of the displayed image due to the color gradient.

8th shows a plan view of the display device 10 according to 1 in a sixth state. In the sixth state, the pixels become 12 controlled so that by means of the display device 10 , At least with the illustrated pixel arrangement, a cyan-colored image is displayed.

The representation of the cyan-colored image is dependent on image data, that of the display device 10 are supplied and containing the image information, such that in the region of the pixel arrangement shown an exclusively cyan-colored image is displayed.

Alternatively, by means of the display device 10 depending on the image data, a magenta or a yellow image may be displayed.

9 shows a plan view of the display device 10 according to 4 in the sixth state, wherein the individual light emitting devices 18 . 20 . 22 the display device 10 are shown. So that the display device 10 the cyan color image becomes the red light emitting devices 20 not activated. Since that in 5 middle red light emitting device 20 in the bad state, that is the first light-emitting device 24 can be designated, and the second light-emitting device 24 is not activated in the sixth state, the red light emitting devices adjacent thereto become 20 not to compensate for the bad condition of the first light-emitting device 24 used. Thus, the compensation of the bad state of the first light-emitting device is performed 24 depending on the image data.

10 shows a flowchart of an embodiment of a method for operating a display device, for example, the display device explained above 10 , The procedure serves to cause a bad condition of one of the pixels 12 , in particular one of the light-emitting components 18 . 20 . 22 of the pixel 12 . in particular of the first light-emitting component 24 , and depending on the bad state, the one or more corresponding second light emitting devices 26 such that the effects of the poor condition of the first light emitting device 24 be compensated, so that the total display device 10 despite the poor condition of the first light-emitting device 24 has a high display quality. This helps to ensure that the display device 10 has a high fault tolerance and a long life.

In a step S2, the actual state of one of the light emitting devices 18 . 20 . 22 determined.

In a step S4, the detected actual state becomes the predetermined state of the corresponding light-emitting device 18 . 20 . 22 compared. The default state depends on the image currently being displayed and, in particular, on the current image data. The default state may be part of a predetermined set of states. The amount of states may be from the image data and / or from an age of the display device 10 depend. As a result, for example, an actual state of a relatively old display device 10 Still considered to be good condition and the same actual condition may be present in a relatively young display device 10 already considered a bad condition, whereby a natural, error-free aging of the display device 10 and all pixels 12 the display device 10 Account can be taken. This is achieved in that the predetermined states are given more generously with increasing age of the display device. The predetermined state or the set of predetermined states depending on the image data can be used, for example, in the display device 10 determined empirically in a new state and then on a storage unit of the display device 10 be stored.

The determined actual state can be classified as a bad state as a result of the comparison, if the actual state does not correspond to the predetermined state. For example, if the actual state is the actual brightness of the light-emitting device 18 . 20 . 22 is determined, the predetermined state is a minimum brightness, and when the actual brightness becomes smaller than the minimum brightness, the actual state of the corresponding light-emitting device becomes 18 . 20 . 22 classified as bad. If, for example, in contrast thereto as the predetermined state, the electrical resistance of the light-emitting component 18 . 20 . 22 is determined, the predetermined state is a maximum resistance, and when the detected resistance becomes larger than the maximum resistance, the actual state of the corresponding light-emitting device becomes 18 . 20 . 22 classified as bad.

If the condition is satisfied in step S4, the processing is continued in step S6. If the condition is not satisfied in step S4, the processing is continued again in step S2, for example, for the same light-emitting device 18 . 20 . 22 or for another light emitting device 18 . 20 . 22 ,

In step S6, the drive of the second light-emitting component 26 and optionally also the third light emitting device 28 changed so that thereby the bad state of the first light-emitting device 24 is compensated. The second light-emitting component 24 may depend on whether the state of the first light-emitting device 24 is slightly poor or massively bad, the latter, for example, in a total failure, are operated so that the current control of the second light-emitting device 26 is only slightly changed or greatly changed, the current control of the second light-emitting device 24 depends on the image data.

The process can be repeated successively or permanently for the pixel 12 and / or simultaneously for multiple pixels 12 be performed. The method can, in particular, be repeated successively or permanently for the light-emitting components 18 . 20 . 22 and / or simultaneously for a plurality of light-emitting components 18 . 20 . 22 be performed. In other words, the pixel can 12 or a variety of pixels 12 be monitored simultaneously and / or successively by means of the method and, where appropriate, their bad states are compensated. In particular, in other words, one of the light-emitting components 18 . 20 . 22 or a plurality of the light emitting devices 18 . 20 . 22 be monitored simultaneously and / or successively by means of the method and, where appropriate, their bad states are compensated.

11 shows a flowchart of an embodiment of a method for operating a display device, for example, the display device explained above 10 , For example, the method may be substantially the same as in 10 However, it is more detailed. The procedure serves to cause a bad condition of one of the pixels 12 , in particular one of the light-emitting components 18 . 20 . 22 of the pixel 12 , in particular of the first light-emitting component 24 to recognize and depending on the bad state, the one or more corresponding second light-emitting devices 26 such that the effects of the poor condition of the first light emitting device 24 be compensated, so that the total display device 10 despite the poor condition of the first light-emitting device 24 has a high display quality. This helps to ensure that the display device 10 has a high fault tolerance and a long life.

In a step S8, the actual value of the parameter of the pixel 12 , in particular one of the light-emitting components 18 . 20 . 22 of the pixel 12 , determined.

In a step S10, the detected actual value of the parameter is compared with the predetermined desired value of the parameter. The predetermined target value of the parameter depends on the image currently being displayed and in particular on the current image data. The predefined setpoint value of the parameter may be part of a predefined set of setpoint values, for example a value from an interval at predefined setpoint values. The interval of the predetermined target values may be from the image data and / or from an age of the display device 10 depend. As a result, for example, an actual value of the parameter in a relatively old display device 10 can still be representative of a good condition and the same actual value can be seen on a relatively young display device 10 already representative of a poor condition, resulting in a natural, error-free aging of the display device 10 and all pixels 12 the display device 10 Account can be taken. This is achieved in that the interval of the predetermined target values is given more generously as the display device ages. The target value of the parameter depending on the image data may be, for example, in the display device 10 determined empirically in a new state and then on a storage unit of the display device 10 be stored. The setpoint value of the parameter can also be specified as a threshold value.

As an alternative to the comparison of the actual value of the parameter and the desired value of the parameter, the actual value of the parameter can be compared with a predetermined threshold value. The threshold may vary depending on the image data and / or the age of the display device 10 be specified. The determined actual state can be classified as a bad state as a result of the comparison, if the actual value of the parameter of the corresponding light-emitting device 18 . 20 . 22 is the same as the predetermined threshold or exceeds the predetermined threshold. The fact that the value exceeds the predetermined threshold value may mean that the value exceeds or already exceeded the predetermined threshold value from top to bottom or that the value exceeds or has already exceeded the predetermined threshold value from bottom to top. Specifically, the value exceeding the predetermined threshold may mean that the value is greater or less than or greater than the predetermined threshold depending on which parameter is being monitored. If, for example, as a parameter, the brightness of the light emitting device 18 . 20 . 22 is determined, the predetermined threshold value is a minimum brightness value, and when the detected value of the brightness becomes smaller than the minimum brightness value, the state of the corresponding light-emitting device becomes 18 . 20 . 22 classified as bad. In contrast, if, for example, as a parameter, the electrical resistance of the light emitting device 18 . 20 . 22 is monitored, the predetermined threshold value is a maximum resistance value, and when the detected value of the resistance becomes larger than the maximum resistance value, the state of the corresponding pixel is classified as bad.

If the condition is satisfied in step S10, the processing is continued in step S12. If the condition is not satisfied in step S10, the processing is continued again in step S8, for example, for the same light-emitting device 18 . 20 . 22 or for another light emitting device 18 . 20 . 22 ,

In a step S12, the drive of the second light-emitting component 26 and optionally also the third light emitting device 28 changed so that thereby the bad state of the first light-emitting device 24 is compensated by depending on the actual value of the parameter of the first light-emitting device 24 the target value of the drive quantity of the second light-emitting component 26 is determined. The target value of the drive quantity may depend on whether the state of the first light-emitting component 24 is slightly bad or massively bad, the latter, for example, in a total failure, so determined that the current control of the second light-emitting device 26 is only slightly changed or greatly changed, the current control of the second light-emitting device 24 depends on the image data.

In a step S14, the second light-emitting device becomes 24 controlled depending on the target value of the control variable.

The process can be repeated successively or permanently for the pixel 12 and / or simultaneously for multiple pixels 12 be performed. The method can, in particular, be repeated successively or permanently for the light-emitting components 18 . 20 . 22 and / or simultaneously for a plurality of light-emitting components 18 . 20 . 22 be performed. In other words, the pixel can 12 or a variety of pixels 12 be monitored simultaneously and / or successively by means of the method and, where appropriate, their bad states are compensated. In particular, in other words, one of the light-emitting components 18 . 20 . 22 or a plurality of the light emitting devices 18 . 20 . 22 be monitored simultaneously and / or successively by means of the method and, where appropriate, their bad states are compensated.

12 FIG. 12 shows a flow diagram of one embodiment of a method for monitoring one of the pixels 12 , in particular one of the light-emitting components 18 . 20 . 22 , The method serves to easily and reliably prevent a bad state of the corresponding light-emitting device 18 . 20 . 22 to recognize. The method can be carried out in particular when the light-emitting components 18 . 20 . 22 organic light emitting devices are.

In a step S16, one of the light emitting devices becomes 18 . 20 . 22 disabled. The step S16 may, for example, in the course of a shutdown of the display device 10 be performed.

In a step S18, a value of a voltage which is applied to the switched-off light-emitting component is detected 18 . 20 . 22 is present, in particular shortly after step S16, for example, 0.1 s to 5 s, for example 1 s to 2 s after step S16.

If the light emitting device 18 . 20 . 22 has a short circuit, which leads to a total failure of the light emitting device 18 . 20 . 22 can lead or already to a total failure of the light-emitting device 18 . 20 . 22 has led, so discharges an intrinsic capacitance of the corresponding light-emitting device 18 . 20 . 22 quickly over the short circuit, for example, in a period of less than 0.1 s. If the light emitting device 18 . 20 . 22 has no short circuit resulting in a total failure of the light emitting device 18 . 20 . 22 can lead or already to a total failure of the light-emitting device 18 . 20 . 22 has led so discharges the intrinsic capacitance of the corresponding light-emitting device 18 . 20 . 22 only slowly and the value of the voltage detected in step S16 is above a correspondingly predetermined test threshold value.

The intrinsic capacitance is due, for example, to the electrodes of the light emitting device 18 . 20 . 22 before, since these as long as the light-emitting devices 18 . 20 . 22 are operated below their threshold voltage and in particular are not active, as plate capacitors act, which naturally each form a capacitance and at which shortly after switching off an intact light-emitting device 18 . 20 . 22 a certain voltage is applied. The short circuit of the light emitting device 18 . 20 . 22 then acts as a short between the plates of a capacitor and discharges the corresponding capacitor quickly, so that no voltage is applied between the plates.

In a step S20, the state of the light-emitting device becomes 18 . 20 . 22 determined, for example, by the detected value of the voltage is compared with the predetermined test threshold. If the detected value of the voltage is greater than the predetermined test threshold, the state of the light-emitting device becomes 18 . 20 . 22 classified as good. If the detected value of the voltage is less than or equal to the predetermined test threshold, the state of the light-emitting device becomes 18 . 20 . 22 classified as bad.

The invention is not limited to the specified embodiments. For example, the images, colors, and color gradients shown and / or described in the embodiments may vary depending on the image data.

Claims (15)

Method for operating a display device ( 10 ) comprising a plurality of pixels ( 12 ), each having at least one light emitting device, wherein in operation of the display device ( 10 actual states of the light emitting devices are detected, the actual states of the light emitting devices are compared with predetermined states of the respective light emitting devices, and if the comparison reveals that an actual state of a first light emitting device ( 24 ) of the light-emitting components with respect to the predetermined state of the first light-emitting component ( 24 ), at least one second light-emitting component ( 26 ) of the light emitting devices is controlled so that the deteriorated actual state of the first light emitting device ( 24 ) by means of the second light-emitting component ( 26 ), wherein the second light-emitting component ( 26 ) to the first light emitting device ( 24 ) and is arranged to emit light of the same emission color as the first light-emitting device ( 24 ) in the predetermined state.  The method of claim 1, wherein the actual states of the light-emitting devices are detected by detecting actual values of a parameter representative of the actual states of the light-emitting devices, and comparing the actual states with the predetermined states by: the detected actual values of the parameter are compared with predetermined target values of the parameter, which are representative of the predetermined states of the corresponding light-emitting components. A method according to any one of the preceding claims, wherein the deteriorated actual state of the first light-emitting device ( 24 ) by means of the second light-emitting component ( 26 ) is compensated for by a target value of a drive quantity of the second light-emitting component ( 26 ), depending on the deteriorated actual state of the first light-emitting device ( 24 ) is changed.  Method according to one of the preceding claims, in which the actual states are actual brightnesses of the light-emitting components and in which the predetermined states are predefined brightnesses of the light-emitting components. Method according to one of the preceding claims, in which the deteriorated actual state of the first light-emitting component ( 24 ) by means of the second light-emitting component ( 26 ) is compensated for by a brightness of the second light-emitting component ( 26 ) is increased. Method according to one of Claims 3 to 5, in which the drive quantity comprises an operating voltage and / or an operating current for operating the second light-emitting component ( 26 ) and in compensating for the poor actual state of the first light-emitting device ( 24 ) the voltage value of the operating voltage or the current value of the operating current is increased. Method according to one of the preceding claims, in which the driving of the pixels ( 12 ) is performed depending on image data representative of an image to be displayed by the display device, and in which the driving of the second light-emitting device ( 26 ) for compensating the poor actual state of the first light-emitting device ( 24 ) depending on the image data. Method according to Claim 7, in which the second light-emitting component ( 26 ) not to compensate for the poor actual state of the first light-emitting device ( 24 ), if the first light-emitting component ( 24 ) is not operated due to the current image data. Method according to one of claims 7 or 8, in which, if the image to be displayed as a function of the image data in the region of the first and second light-emitting component ( 24 . 26 ) has a color gradient, the second light-emitting component ( 24 ) is selected, depending on the color gradient, among all the light-emitting components that belong to the first light-emitting component ( 24 ) are arranged adjacent to each other and emit the light of the same emission color as the first light-emitting component ( 24 ) in the predetermined state. Method according to one of the preceding claims, in which to compensate for the poor actual state of the first light-emitting component ( 24 ) two or more second light-emitting components ( 26 ). Method according to one of the preceding claims, in which the light-emitting components are arranged in rows and columns and in which the second light-emitting component ( 26 ) in the row direction or in the column direction to the first light-emitting device ( 24 ) is the closest light-emitting component which emits light of the same emission color as the first light-emitting component ( 24 ) in the predetermined state. Method according to one of the preceding claims, in which the light-emitting components are arranged in rows and columns and in which, if the comparison results, the actual state of the first of the light-emitting components ( 24 ) with respect to the predetermined state of the first light-emitting component ( 24 ) is deteriorated, at least a third of the light-emitting components ( 28 ) is driven so that the deteriorated actual state of the first light-emitting device ( 24 ) by means of the third light-emitting component ( 28 ) is compensated, wherein the third light-emitting component ( 28 ) is arranged so that the second light-emitting component ( 26 ) between the first and the third light-emitting device ( 24 . 28 ) is arranged, and is formed so that it emits light of the same emission color as the first light-emitting component ( 24 ) in the predetermined state.  Method according to one of the preceding claims, in which the light-emitting components are organic light-emitting components and in which the corresponding organic light-emitting component is deactivated to determine the actual state of one of the organic light-emitting components and a voltage value of a voltage is detected after deactivation of the organic light-emitting component which is applied to the organic light-emitting device, and the actual state of the corresponding organic light-emitting device is determined depending on the detected voltage value. Display device ( 10 ), comprising: a plurality of pixels ( 12 ), each having at least one light-emitting component, a sensor device which is coupled to the organic light-emitting components and which is formed so that it during operation of the display device ( 10 detects actual states of the light-emitting components, an evaluation unit which is coupled to the sensor device and which is designed such that it compares the detected actual states of the light-emitting components with predetermined states of the corresponding light-emitting components, and a driver unit connected to the evaluation unit and is coupled to the organic light-emitting components and that is designed such that, if the comparison shows that an actual state of a first light-emitting component ( 24 ) of the light-emitting components with respect to the predetermined state of the first light-emitting component ( 24 ) is deteriorated, at least a second of the light-emitting components ( 26 ) such that the deteriorated actual state of the first light-emitting device ( 24 ) by means of the second light-emitting component ( 26 ), wherein the second light-emitting component ( 26 ) to the first light emitting device ( 24 ) and emits light of the same emission color as the first light-emitting component ( 24 ) in the predetermined state.  A display device according to claim 14, wherein the light emitting devices are organic light emitting devices.

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