Method and device for brightness compensation of an LED

Abstract

Method for brightness compensation of at least one light-emitting diode (LED) as a function of a temperature value, comprising: - Defining a time interval that determines how long the temperature value on the light-emitting diode (LED) is measured; - measuring (100) a temperature value with respect to a plurality of light-emitting diodes (LEDs) according to the defined time interval, wherein the temperature value represents an average value of several individual temperature values ​​measured at different measuring locations; - reading (101) a current value from a plurality of current values ​​stored in a memory module, which current value is associated with the read temperature value; - controlling (101) at least one current regulator of a respective light-emitting diode (LED) by means of the read current value; and - Repeating all process steps according to a predetermined cycle that determines a time interval between two iterations.

Description

[0001] The present invention is directed to a method for brightness compensation in at least one light-emitting diode. The proposed method achieves a consistently constant brightness of the LED regardless of temperature fluctuations. The invention is further directed to a correspondingly configured device and a memory module for use in the proposed method.

[0002] US 2008 / 0 079 371 A1 shows an arrangement for the color correction of a light-emitting diode as a function of a measured temperature, whereby a current value is calculated.

[0003] US 2012 / 0 319 585 A1 shows another arrangement for color correction of a light-emitting diode depending on a measured temperature.

[0004] WO 2014 / 067 830 A1 shows detecting and adapting the LED control to the temperature using lookup tables.

[0005] Light-emitting diodes are used in a wide variety of colors, sizes, and designs. They are used as signal and light emitting devices, including in the automotive sector. Typically, an LED is designed to provide a constant brightness. The disadvantage here is that brightness decreases with increasing temperature. State-of-the-art methods exist for adjusting brightness. Known methods primarily address dimming LEDs, while solutions for general brightness compensation are disadvantageous because temperature fluctuations are typically not or only insufficiently taken into account.

[0006] Known methods utilize pulse width modulation (PWM), which takes advantage of the inertia of the components used, resulting in a uniform brightness even when the LED is switched on or off in a certain proportion. The brightness is then adjusted depending on the ratio of the on state to the off state. Such pulsing of the LED is typically not perceived by the human eye, and a uniformly adjustable brightness results from this control.

[0007] Furthermore, it is possible to integrate a pulse generator into the constant current source circuit, whereby the supply voltage remains the same and the clocking of the lamps is carried out with the current source itself, which operates in pulse mode.

[0008] For this purpose, control circuits are known that regulate the LEDs to an adjustable setpoint, with the setpoint being adjustable by a controller. Dimming LEDs is achieved according to known methods directly by dimming the current through the LEDs. Control logics for regulating the current supply to the LED, also depending on the LED's temperature, are also known.

[0009] Light-emitting diodes (LEDs) are used in many application scenarios where they are at least not considered to be inferior to incandescent bulbs. While incandescent bulbs can be easily dimmed in terms of brightness, methods are known for LEDs that, for example, control these LEDs using a predetermined control pattern, thereby enabling optical dimming. In contrast, however, it is often desired that an LED be brightened when, for example, the ambient temperature rises. This is the case because LEDs typically exhibit a luminous behavior that reduces the emitted luminosity as the temperature rises.

[0010] Furthermore, it is known to measure a specific brightness of an LED and, depending on the brightness of this LED, to adjust the LED so that it reaches a predetermined brightness value. However, this requires optical sensors. Methods are also known that provide logic that triggers the control of an LED so that preset brightness values ​​are achieved. However, this requires complex components, which leads to increased technical complexity and thus manufacturing costs.

[0011] It is therefore an object of the present invention to provide a method and a device which allow the brightness of a light-emitting diode to be set constantly, regardless of its ambient temperature, with little technical effort. The aim is therefore that even if the brightness of a light-emitting diode decreases due to an increase in the ambient temperature, this very light-emitting diode is controlled in such a way that the desired brightness value is re-established. Thus, LEDs should not vary in brightness depending on the temperature, but rather if these light-emitting diodes heat up during operation or adjacent components radiate heat, the light-emitting diodes should always provide the same brightness. It is furthermore an object of the present invention to provide a memory module which provides data for brightness compensation of at least one light-emitting diode.

[0012] The problem is solved by the features of the main claim. Further advantageous embodiments are specified in the subclaims.

[0013] Accordingly, a method for brightness compensation of at least one light-emitting diode as a function of a temperature value is proposed. The method comprises the steps of measuring a temperature value with respect to a plurality of light-emitting diodes and reading a current value from a plurality of current values ​​stored in a memory module, which current value is associated with the read temperature value. Furthermore, at least one current regulator of each light-emitting diode is controlled using the read current value.

[0014] According to the invention, brightness compensation is achieved efficiently by providing essentially analog components that typically adjust the brightness of a light-emitting diode independently of its color value. Thus, the method according to the invention can be combined with conventional methods such that, for example, a color value is adjusted using pulse width modulation, and furthermore, the brightness of the light-emitting diode is adjusted solely by controlling the light-emitting diode based on the read current value. According to one aspect of the present invention, a constant current regulator can be used for this purpose. Furthermore, it is possible to adjust the color value of a light-emitting diode using an on / off modulator.

[0015] In the present case, a light-emitting diode should be understood as a device which can also comprise further LED chips. Thus, the light-emitting diodes according to the invention in turn consist of further light-emitting diode units or semiconductor chips. For example, the known red, green and blue light-emitting diode units can be used for this purpose, which are adjusted with respect to the so-called RGB color space. These individual light-emitting diode units are combined in an light-emitting diode housing in such a way that their light combines to form a predetermined color value. For example, it is possible to adjust a mixing ratio such that the light-emitting diode as a whole emits white light. Further devices, such as a diffuser, can also be provided for this purpose. When individual light-emitting diodes or light-emitting diode units are combined, any desired colored light can be achieved by appropriately controlling the individual components.This makes it possible to create color transitions, for example. According to the invention, so-called multi-LED components can be used, for example.

[0016] The proposed method makes it possible to control the brightness essentially independently of the color setting. According to the invention, it is thus possible to avoid the need for additional bits to be provided when setting the color value in order to also adjust the brightness of the LED along with the color value. By controlling a current value of the LED, the disadvantage of conventional methods is overcome, namely that a color value, for example, has to be set using 8 bits, but in this case 10 bits have to be transmitted. According to the known methods, a so-called remainder must remain in the coding, which is used to adjust the brightness. This is overcome according to the invention in that the bit values ​​to be used are used essentially solely for color adjustment.For this purpose, analog components are typically provided which cause the current controller to be controlled using the appropriate current value, regardless of the set color value.

[0017] Furthermore, the current value is provided in a particularly advantageous manner by means of a readout. This offers the advantage that no separate logic, for example by means of digital components, needs to be provided. The logic provided in conventional methods for providing the current value is implemented according to the invention merely by reading a data memory. Thus, no further method steps are necessary which would cause a current value to be calculated. Thus, according to the invention, it is possible to provide a suitable current value with which the LEDs are controlled with little technical effort, i.e. with highly efficient, for example analog, components and a few method steps.

[0018] According to one aspect of the present invention, this can be achieved in that the current values ​​which cause a certain brightness in an LED can be determined before carrying out the method or in preparatory method steps of the method. However, according to the invention, this typically only takes place once and can thus be used with a large number of uniform light-emitting diodes. This enables light-emitting diode compensation devices which advantageously require fewer components, and in particular less complex components. Furthermore, the proposed method enables robust determination of the current value such that calculation or logic errors are avoided when determining the current value. Furthermore, it is advantageous according to the invention that the stored current values ​​can be tested as required before corresponding components are delivered.Thus, these current values ​​are not generated at runtime, but rather are determined a priori, tested and simply provided using efficient hardware.

[0019] Since LEDs typically shine less brightly with increasing temperature, it is necessary to measure at least one temperature value in one process step. The temperature value can relate to a temperature condition of the LED. It can therefore be advantageous to determine the temperature value directly at the LED. However, it is also possible to determine an ambient value of the LED in the immediate vicinity of the LED. It can also be advantageous to determine several temperature values ​​and combine them into a single temperature value. In this way, temperature values ​​of adjacent components can also be determined and, after being added together, these can be averaged. If LEDs are connected in series, several temperature values ​​can be measured for a specific LED, and these values ​​can be averaged.This can also be achieved using analog circuits and does not require any digital components.

[0020] In a further process step, a current value is read out from several current values ​​stored in a memory module, which is assigned to the read temperature value. For this purpose, current values ​​must be determined in preparatory process steps. These current values ​​generate a certain brightness depending on a temperature value. For example, a certain LED requires a current of 5 mA, or 5 milliamperes, at a temperature of 24°C. Since the LED shines less brightly with increasing temperature, a current of 10 mA may be necessary at a temperature of 50°C to achieve the same brightness as 5 mA at a temperature of 24°C. If, on the other hand, the temperature of the LED is 100°C, a current of just 20 mA may be necessary to achieve the same brightness.Thus, the same LED at 24°C and driven by 5 mA achieves the same brightness as the same LED at 50°C when driven by 10 mA. Thus, the brightness behavior of the LED is adjusted depending on the measured temperature value. This is particularly advantageous because the observer of the LED always perceives the same brightness, even if the temperature of the LED changes during operation.

[0021] Thus, according to the invention, the brightness of the LED is adjusted essentially uniformly, with the brightness being compensated in such a way that the human eye perceives no difference in brightness. Thus, it may be necessary to run the process iteratively so that certain temperature jumps are immediately detected and the driving current value is readjusted.

[0022] For this purpose, it may be possible to define a time interval that determines how long the temperature value at the LED or in its surroundings is measured. A predetermined cycle can also be maintained, which determines the time interval between two iterations of the process. For example, it may be determined that the temperature is 30°C, and after 5 seconds, a further determination of the temperature value reveals that the LED has heated up to such an extent that the temperature is now 31°C. Thus, depending on the measured 31°C, the corresponding current value is read out, and the brightness of the LED is compensated.

[0023] Those skilled in the art will be familiar with additional intervals or frequencies that can be used to measure temperatures and control LEDs. This can be adjusted, for example, depending on the components used. It is also possible to define temperature intervals in such a way that a current value is assigned to each temperature range. For example, it is possible to assign a current value to each temperature increment of 10°C or 20°C. For example, a current value can be assigned to a temperature interval from 60°C to 80°C. This makes it possible to provide the current value so efficiently that the brightness of the LED does not have to be adjusted constantly, but only when the limits of a temperature interval are exceeded.

[0024] A logical table is suitable for storing the individual current values ​​along with temperature values ​​or temperature intervals. This is not limited to an actual table; rather, any representation is possible, for example, at least one attribute / value pair or at least one value / value pair. It is particularly advantageous to store the individual values ​​in such a way that they can be read and processed efficiently.

[0025] This makes hard-coded circuits or hard-wired components suitable. This is possible because no changes occur after the corresponding components are delivered, allowing the corresponding logical table to be provided in a hard-wired manner.

[0026] Accordingly, the memory module or the saving of the current values ​​must be interpreted in such a way that any type of memory module or saving is possible. Thus, the memory module does not have to be configured dynamically in such a way that it must be writable during runtime, i.e. while the current controller is being controlled. Rather, saving only requires the corresponding information to be incorporated into a hardware module in some way. It may also be necessary to provide not a single memory module, but rather to provide additional components that enable the current value to be provided. The assignment of the current values ​​to the temperature values ​​also takes place in preparatory process steps and results implicitly when operating the proposed method because a current value is already available for each measured temperature value.

[0027] Once this one current value has been read out, or once it has been identified which current value is necessary for brightness compensation based on the measured temperature value, at least one current controller for each LED is controlled by means of the read-out power network. The brightness value of the LED is thus set by the magnitude of the respective current value. The current controller is thus configured to apply the predetermined voltage to the LED or to the LED units. The LED is thus controlled by means of the read-out current value. According to the invention, this continues until a new temperature value, including an associated current value, is determined and the LED is controlled by this new current value. The brightness of the LED is thus permanently set, although this requires different current values ​​at different times depending on the prevailing temperature.

[0028] According to one aspect of the present invention, at least one sensor is provided for measuring the temperature value at at least one measuring location. Multiple measuring locations are suitable for this purpose, for example, a measuring location at exactly one LED, a measuring location at each LED, a measuring location at a microcontroller connected to an LED, or a measuring location in the immediate vicinity of an LED. For example, the proposed method is used with several interconnected LEDs. In this case, it is possible for several LEDs to be connected in series, for example. If this plurality of LEDs is installed in an automobile, different temperatures may prevail at different locations. This means that the LEDs can not only heat up on their own, but heat can also be radiated by adjacent components.Thus, the invention makes it possible to take this into account and determine a temperature value at multiple measurement locations. An immediate environment here describes an environment that allows a conclusion to be drawn about the temperature of the LED. Therefore, this temperature does not have to be measured directly at the LED; instead, a temperature sensor can be spaced from the LED such that any temperature input from neighboring components is negligible. In particular, this means that there must be no physical contact in the sense of touching the temperature sensor and the LED.

[0029] According to a further aspect of the present invention, the light-emitting diode is present as a triplet of three light-emitting diode units, and the light-emitting diode units each emit a different color. This has the advantage that colored LEDs can be used. In particular, the invention makes it possible to continue using conventional LEDs and only control the current regulator of these LEDs in such a way that the inventive advantage is achieved. Furthermore, the proposed method has the advantage that brightness compensation can be performed independently of the color setting of the light-emitting diode. Those skilled in the art are aware of other light-emitting diodes which have light-emitting diode units that can be reused according to the invention. For example, a light-emitting diode unit is present as a semiconductor component or as any other light-emitting component.Emitting different colors, or light in different wavelengths, serves to set a predetermined color value.

[0030] According to a further aspect of the present invention, the memory module provides a plurality of temperature values, each of which is associated with a current value. This has the advantage that a plurality of temperature values ​​can be taken into account, and the temperature values ​​can be predetermined with respect to the current values ​​in such a way that the same brightness value of the LED is always established. In particular, the number of current value / temperature value pairs can be determined in a preparatory method step.

[0031] According to a further aspect of the present invention, the read current value is assigned to a temperature interval within which the measured temperature value lies. This has the advantage that, if a specific temperature value is present, the LED does not have to be controlled immediately; instead, it can first be checked whether the temperature value lies within a certain interval. For example, a drop in the temperature value does not immediately lead to a visible change in the brightness value. Thus, one can wait until the measured temperature value falls below a certain threshold, which requires an adjustment of the brightness. Furthermore, this has the advantage of proposing a particularly effective method that can also be operated with low-performance components. The number of individual brightness compensations can thus be adjusted depending on the size of the temperature intervals.Furthermore, it is also possible to define the temperature intervals in such a way that they are not equidistant. Thus, a first temperature interval can have a first temperature range of 5°C, and a second temperature interval can have a second temperature range of 10°C. By choosing the respective sizes of the temperature intervals, the underlying physical components can be taken into account and, above all, the behavior of the LED can be taken into account.

[0032] According to a further aspect of the present invention, the current value is selected with respect to the temperature value such that brightness compensation of the LED to be controlled is established as a function of a prevailing temperature. This has the advantage that not only is the brightness of the LED adjusted, but rather that a brightness adjustment is performed over time in such a way that the brightness is always compensated as a function of the temperature value. This is the case because the brightness value changes as a function of the temperature value, and if a new temperature value is detected, the brightness value can also be compensated again such that it meets the preset target value.

[0033] According to a further aspect of the present invention, the current regulator is a constant current regulator. This has the advantage that known components can be reused, and the arrangement only needs to be adapted to implement the method according to the invention. Thus, known current regulators can be used, which control the LED with the advantageously determined current value.

[0034] According to a further aspect of the present invention, the temperature value represents an average of several measured individual temperature values. This has the advantage that several temperature values ​​determined at different measuring locations can be easily combined to form a single temperature value. This can be implemented, for example, using hard-wired logic. However, according to the invention, it is also possible to design the device or method such that no logic at all is required. In this case, only a readout of the memory module is initiated, without these values ​​having to be interpreted in any way. Thus, only a single lookup operation is performed without any logic.

[0035] According to a further aspect of the present invention, the storage of a plurality of temperature values, each including a current value, is carried out using at least one determination routine. Possible methods include empirical determination, measurement, two-point measurement, calculation, and reading of the respective current values. Thus, storing the current values ​​for the respective temperature values ​​involves filling the logical table that describes which current value must be applied at which temperature. This can be done in preparatory method steps such that a specific current value is applied to a light-emitting diode at a specific temperature and the brightness is measured. This is carried out iteratively so frequently that it is possible to determine how the temperature or the applied voltage or the current value affects the emission of light.This makes it possible to empirically determine which current value must be applied to the LED at which temperature in order to achieve a certain brightness. The attribute-value pairs or value / value pairs that result in a constant brightness are then saved. This includes, for example, measuring in such a way that an applied current value is varied such that the brightness results depending on the prevailing temperature. This can also be calculated in advance, which typically requires additional parameters. For this purpose, it is possible to request the relevant parameters from a manufacturer, for example. Corresponding tables can also be provided by the LED manufacturer and then simply need to be read out. Furthermore, two-point measurement is familiar to those skilled in the art, which can be used to determine suitable attribute-value pairs.

[0036] According to a further aspect of the present invention, the plurality of stored current values ​​are adjusted with respect to the respective temperature value in such a way that they always result in the same brightness when driving the LED. This has the advantage that the same brightness value always prevails, or a substantially identical brightness value prevails, or a brightness value prevails whose difference from a previous brightness value is not perceptible to the human eye.

[0037] According to a further aspect of the present invention, the at least one current regulator is controlled by means of the read current value independently of the setting of a color value of the LED. This has the advantage that known methods can continue to be used to set the color of the LED. In particular, a specific bit value can be used to set the color value, which does not require any additional bits to set the brightness. This also has the advantage that, for example, 8 bits are sufficient to set the color value and 10 bits are not required to set a color value and brightness, as is conventionally the case. This has the disadvantage that the pulse width modulation would have to generate faster edges, and additional bandwidth would be wasted.According to the invention, this is avoided by setting the color values ​​separately and independently adjusting the brightness using the current controller.

[0038] The invention is also achieved by a device for brightness compensation of at least one light-emitting diode as a function of a temperature value. The device comprises at least one sensor configured to measure a temperature value with respect to a plurality of light-emitting diodes, as well as an interface component configured to read out a current value from a plurality of stored current values ​​from a memory module, which current value is associated with the read-out temperature value. Furthermore, a current controller is provided, which is configured to control at least one light-emitting diode at a time using the read-out current value.

[0039] The problem is also solved by a memory module with stored current values, each of which is assigned to a temperature value in such a way that when a light-emitting diode is controlled with the respective current value at a prevailing temperature according to this temperature value, the light-emitting diode always shines with the same brightness.

[0040] Furthermore, a storage medium is provided with control commands for executing a method according to one of the aspects described above.

[0041] Thus, in particular, hardware components and a method are proposed that enable brightness compensation of one or more light-emitting diodes to be carried out in a particularly efficient manner. It is particularly advantageous that the device is suitable for implementing the proposed method and thus structurally adopts its features. The method can also be used to operate the device, and the memory module according to the invention can be used both in the proposed method and in the proposed device.

[0042] Further advantageous aspects of the present invention will now be described with reference to the accompanying figures. They show: Fig. 1: a diagram with values ​​that set a brightness compensation as a function of temperature values ​​according to one aspect of the present invention; Fig. 2: a schematic flow diagram of a method for brightness compensation according to one aspect of the present invention; Fig. 3: a device according to the invention for brightness compensation with further components according to an aspect of the present invention; and Fig. 4: storing current values ​​as a function of temperature values ​​according to one aspect of the present invention.

[0043] Fig. 1 shows brightness values ​​on the Y-axis, which decrease in percentage from the maximum brightness of 100% to a non-illumination of 0%. Temperature values ​​are entered on the X-axis, which refer to the corresponding LED. The course of the upper line shows, which in the present Fig. 1 from the top left to the bottom right, indicates that the brightness of the LED decreases in the direction of increasing temperature. In contrast, the lower line, which in the present Fig. 1 runs from bottom left to top right, indicating that with increasing temperature, higher current values ​​are necessary to achieve a certain brightness. Thus, the left scale of the Y-axis refers to the upper curve and the right scale to the lower curve. The curve is replaced by a line. Whether the behavior is now as linear as Fig. 1, or whether curves are to be provided, depends on the respective LEDs. For this purpose, the present Fig. 1 is to be understood merely schematically in such a way that an increase in the temperature value also requires an increase in the current value in order to set the same brightness. Also, the values ​​stored in the memory module typically comprise a plurality of curves, with only one of them being shown in the present example. Fig. 1 is registered.

[0044] Fig. Figure 2 shows a schematic flow diagram of the method according to the invention, wherein a temperature value is measured 100 with respect to a plurality of LEDs. This is followed by a reading 101 of a current value from a plurality of current values ​​stored in a memory module, which current value is associated with the read temperature value. In a subsequent method step, at least one current regulator of a respective LED is controlled 102 using the read current value. As in the present Fig. 2, it is particularly advantageous to run the method iteratively in such a way that temperature values ​​are always measured and subsequently a current value is read out, on the basis of which the light-emitting diode is controlled.

[0045] Furthermore, it is also possible, after measuring 100 a temperature value, to first read out a current value 101 and, if the current value has not changed, to branch directly back to method step 100. This is particularly advantageous if a temperature range is defined and, after measuring a temperature value, no adjustment of the current value is necessary if the temperature value lies within a temperature range for which the corresponding current value has already been read out. Since the same current value should prevail within this temperature range, no further control of the LED is required. Only if the read temperature value exceeds a certain threshold value should the method branch to control the current regulator in step 102.

[0046] Fig. Figure 3 shows the device 200 according to the invention for brightness compensation of at least one light-emitting diode (LED). To adjust color values, so-called ON / OFF modulators are provided, which set a specific mixing ratio of the individual LED units. For this purpose, a so-called RGB code is provided, for which 8 bits are provided. As in the present Fig. However, as can also be seen in Figure 3, the LED units are controlled separately by the device 200 according to the invention. This means that the color value is set independently of the brightness setting. For this purpose, the device 200 can, for example, be connected to a memory module that provides the table with the corresponding current values. It may also be necessary to provide additional components, such as a digital-to-analog converter. It is particularly advantageous here that the device 200 does not calculate current values ​​and therefore does not provide any logic for this purpose, but rather that this device 200 merely looks up the corresponding values ​​in a connected memory module and thus obtains the corresponding values. Thus, the ON / OFF modulators operate independently of the current value setting. In particular, it is not necessary to equip the device 200 with a powerful processor.Thus, the advantageous brightness compensation can be carried out in an efficient manner and with little technical effort.

[0047] Fig. Figure 4 shows a schematic diagram of how current values ​​can be provided as a function of measured temperature values. This can be used in the method according to the invention, the device, as well as in the memory module. Current values ​​are entered on the Y-axis, and brightness values ​​on the X-axis. It is thus clear that a certain current value is required for a certain bit value. For this purpose, the right-hand side of the present Fig.Four temperature intervals are specified, each requiring a specific current value to achieve the preset brightness. As can be seen from the set of lines emanating from the zero point, the corresponding current value can be determined using an angle that is set depending on the prevailing temperature value. It is particularly advantageous that this can be done before implementing the method according to the invention, so the results only need to be saved.

[0048] As can be seen in the diagram, the current values ​​must be set correspondingly steeper with higher temperature values. Thus, the angle between the x-axis and the line array increases with increasing temperature. For example, a maximum current value at a maximum temperature of 125°C can be as low as 20.7 mA. At a temperature of -40°C, a current value of 4.66 mA may be sufficient. As can also be seen here, greater compensation is necessary with increasing temperature.

[0049] However, it should be noted that this is only one possible approach for setting the current value / temperature value pair. For example, it is also possible to enter a current value for each temperature interval, as shown on the right. For example, the values ​​entered on the Y-axis, each marked with an X—in this case, three Xs—are intended for the temperature range 60°C to 80°C. Each such entry along the Y-axis can be made, for example, depending on a brightness value on the X-axis.

[0050] This procedure can be applied to the method according to the invention as well as to the device according to the invention and the memory module. A particularly preferred embodiment of the present invention is the use of the described aspects in an automobile. However, the present invention is not generally limited to this; rather, those skilled in the art will recognize various other possible applications for consistently providing a viewer of an LED with consistent brightness.

Claims

[1] Method for brightness compensation of at least one light-emitting diode (LED) as a function of a temperature value, comprising: - Defining a time interval that determines how long the temperature value on the light-emitting diode (LED) is measured; - measuring (100) a temperature value with respect to a plurality of light-emitting diodes (LEDs) according to the defined time interval, wherein the temperature value represents an average value of several individual temperature values ​​measured at different measuring locations; - reading (101) a current value from a plurality of current values ​​stored in a memory module, which current value is associated with the read temperature value; - controlling (101) at least one current regulator of a respective light-emitting diode (LED) by means of the read current value; and - Repeating all process steps according to a predetermined cycle that determines a time interval between two iterations. [2] Method according to claim 1, wherein at least one sensor for measuring (100) the temperature value is arranged at at least one measuring location from a group of measuring locations, the group comprising: at exactly one light-emitting diode (LED), at each light-emitting diode (LED), at a microcontroller which is connected to a light-emitting diode (LED) and in an immediate vicinity of a light-emitting diode (LED). [3] Method according to claim 1 or 2, wherein the light-emitting diode (LED) is present as a triple of three light-emitting diode units (LED) and the light-emitting diode units (LED) each emit a different color. [4] Method according to one of the preceding claims, wherein the storage module provides a plurality of temperature values, each of which is associated with a current value. [5] Method according to one of the preceding claims, wherein the read current value is assigned to a temperature interval in which the measured temperature value lies. [6] Method according to one of the preceding claims, wherein the current value is selected with respect to the temperature value such that a brightness compensation of the light-emitting diode (LED) to be controlled is established as a function of a prevailing temperature. [7] Method according to one of the preceding claims, wherein the current regulator is a constant current regulator. [8] Method according to one of the preceding claims, wherein the storing of a plurality of temperature values ​​together with a respective current value is carried out using at least one current value determination routine from a set of routines, the set comprising: an empirical determination, a measurement, a two-point measurement, a calculation and a reading of the respective current values. [9] Method according to one of the preceding claims, wherein the plurality of stored current values ​​are adjusted with respect to the respective temperature value in such a way that they always cause the same brightness when driving the light-emitting diode (LED). [10] Method according to one of the preceding claims, wherein a control (102) of the at least one current regulator by means of the read-out current value takes place independently of a setting of a color value of the light-emitting diode (LED). [11] Device (200) for brightness compensation of at least one light-emitting diode (LED) as a function of a temperature value, wherein the device is configured to define a time interval which determines how long a temperature value is measured at the light-emitting diode (LED) and to repeat all work steps according to a predetermined clock which determines a time interval between two iterations, comprising: - a plurality of sensors configured to measure the temperature value with respect to a plurality of light-emitting diodes (LEDs) according to the defined time interval, wherein the temperature value represents an average of a plurality of individual temperature values ​​measured at different measuring locations; - an interface component configured to read out a current value from a plurality of stored current values ​​from a memory module, which is associated with the read-out temperature value; and - a current controller configured to control at least one light-emitting diode (LED) by means of the read current value. [12] Storage medium with control commands for executing a method according to one of claims 1 to 10.

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