EP3554194A1 - Illumination device intended for a vehicle light comprising multiple semiconductor light sources and method for operating the same - Google Patents

Abstract

A method for operating a lamp (01) provided for a vehicle lamp with a plurality of semiconductor light sources (02) and a corresponding lamp (01) are described. The method comprises the method steps: formation of at least two semiconductor light source groups (03), each with a linear current source (04) and at least one semiconductor light source strand (05) connected to this, each of at least two semiconductor light sources (02) arranged in series, - detection of a On-board electrical system voltage (U) of a vehicle equipped with the vehicle lamp, - comparison of the detected on-board electrical system voltage (U) with a voltage threshold value (U), - interconnection of at least two semiconductor light source groups (03) in series to form a semiconductor light source group strand (06) with a normal vehicle electrical system voltage higher than the voltage threshold value (U), and - interconnection of at least two semiconductor light source groups (03) in parallel with each other with a reduced vehicle electrical system voltage lower than the voltage threshold value (U). The illuminant (01) comprises at least two semiconductor light sources Groups (03), each with a linear current source (04) and nd at least one semiconductor light source strand (05) connected to it with at least two semiconductor light sources (02) arranged in series. In addition, it includes comparison means for comparing an on-board electrical system voltage (U) with a voltage threshold value (U), and switching means connected to the comparison means for switching between an arrangement in which at normal on-board electrical system voltage is higher than the voltage threshold value (U) at least two semiconductor light sources Groups (03) are arranged in series to form a semiconductor light source group strand (06), to an arrangement in which, when the vehicle electrical system voltage is lower than the voltage threshold value (U), the semiconductor light source groups (03) of the semiconductor light source group Strands (06) are connected in parallel.

Description

The invention relates to a method for operating a lamp provided for a vehicle light with a plurality of semiconductor light sources, in particular LEDs and / or OLEDs, according to the preamble of claim 1, as well as a suitable for carrying out the method of the invention according to the preamble of claim.

It is well known that when the electric starter of an internal combustion engine of a vehicle is operated when the light is on, the light is darkened by the brief drop in the vehicle electrical system voltage at least at the beginning of the operation of the starter or briefly goes out.

The reason for this is that the vehicle electrical system voltage is typically between 11V and 15V during normal driving with the internal combustion engine running. At least during the operation of the starter, the vehicle electrical system voltage drops to values between typically 7V and 8V.

So far, this was of little concern, since in the past, the annealing except in marked driving school operation was done in stationary traffic and mostly to protect the onboard battery, the light was switched on only after the start.

In times ambient light-controlled light switch-on and start-stop automatisms, which shut down the internal combustion engine - at standstill as at a traffic light or the gas removal while driving - and start again when needed again, this is a Significant impairment of traffic safety, since the light functions, which are to be met when off and on the light of the vehicle lights installed on the vehicle, due to the brightness fluctuations difficult to recognize or can be misinterpreted, for example, when a bright brake light - and be it only briefly - darkens, although still braked, but just the internal combustion engine is started.

Due to their high efficiency in the conversion of electric current into light, semiconductor light sources are increasingly being used as light sources for vehicle use. The semiconductor light sources are hitherto predominantly inorganic, but in some cases organic light-emitting diodes.

Inorganic light emitting diodes consist of at least one light emitting diode semiconductor chip, short LED chip, and at least one, for example, molded by injection molding, the at least one LED chip completely or partially enveloping primary optics. Vehicle lights are also known in which pure LED chips are used without molded primary optics.

Through Hole Technology (THT), Surface Mounted Device (SMD) LEDs, and LEDs are known in which the LED chip is bonded directly to the illuminant carrier in COB (Chip On Board) technology.

THT LEDs, THT LEDs for short, are a well-known type of inorganic light-emitting diodes. They are also referred to as leaded light-emitting diodes, as they consist of an at least in a desired emission transparent encapsulation, e.g. in the form of an encapsulation or an encapsulation, which includes a LED chip with a first electrical connection, for example in the form of an anode terminal connecting bonding wire and connected to a second electrical connection, for example in the form of a cathode terminal, LED chip. From the encapsulation protrude only the designated as little legs wires of the first electrical connection and the second electrical connection as the anode and cathode terminals of the THT-LED. The second electrical connection embodied, for example, as a cathode connection can in this case be provided with a cup mentioned above, in which the LED chip is arranged. The bonding wire leads from the example executed as an anode terminal first connection from outside the cup coming to the LED chip.

SMD LEDs, SMD LEDs for short, are another well-known type of inorganic light-emitting diode. SMD LEDs consist of a leadframe with at least one mounting surface for at least one LED chip and electrical connection surfaces. The leadframe is made of a plastic body with at least one of them At least one mounting surface free recess partially encapsulated. The electrical connection surfaces of the leadframe are also kept free as the electrical connections of the SMD LED for later surface mounting. The at least one LED chip is arranged and electrically contacted at the bottom of the at least one recess extending to the at least one mounting surface. In this case, the LED chip is arranged on a first portion of the leadframe connected to at least one first electrical connection area. A bonding wire connects the LED chip to a second portion of the leadframe, which in turn is connected to at least one second electrical pad. The reaching at its base to the mounting surface recess may be designed reflector-like. The walls of the recess form the above-mentioned primary reflector. Here, the walls can be coated reflective.

COB LEDs, COB LEDs for short, consist of an unhoused LED chip and a bonding wire to be arranged directly on a light carrier. The back side of the LED chip forms the first electrical connection of the COB LED. For electrical contacting, the LED chip on its rear side is directly connected to a first conductor track of a luminous means carrier, e.g. electrically connected by soldering or welding. The bonding wire forming the second electrical connection of the COB LED is likewise connected to a second conductor track of the illuminant carrier, e.g. electrically connected by soldering or welding.

For the sake of completeness, it should additionally be mentioned that other contacts, such as the so-called flip-chip structure are possible, in which the contact means of the LED chip are connected directly to a contacted substrate. In these cases, no bonding wire is used.

In the following, therefore, for the sake of simplicity, no distinction is made between inorganic light-emitting diode and LED chip and instead the term LED is used uniformly for both, unless explicitly stated otherwise. Outstanding properties of LEDs compared to other, conventional light sources of bulbs are a much longer life and a significantly higher light output with the same power consumption. In other words, at the same light intensity, LEDs have lower power consumption compared to other light sources. This can be when using a or several LEDS as a light source of a light source, for example in a vehicle lamp, the load of a vehicle provided for power supply electrical system of a vehicle can be reduced, along with savings in energy consumption of the vehicle. Furthermore, LEDs have a much longer life than other, for use in a vehicle lamp candidate light sources. Due to the longer service life, among other things, the lower failure rate increases the operational safety and, concomitantly, the quality of the vehicle lamp.

An organic light-emitting diode (OLED) is a luminous thin-film component made of organic semiconducting materials with at least one emitter layer enclosed between electrically conductive, for example metallic layers for anode and cathode. The thickness or, in other words, the thickness of the layers is on the order of about 100 nm. Typically, it is 100 nm to 500 nm, depending on the structure. For protection against water, oxygen and for protection against other environmental influences, such as scratch damage and / or pressure loading OLEDs typically encapsulated with an inorganic material, especially glass. Although there are efforts to replace the glass with plastic, but in particular to meet, for example, the service life requirement of vehicle lights and their light sources with several 1000 hours sufficiently well not crowned by the desired success, because the tightness of the alternative materials for the encapsulation not is sufficiently good enough.

In contrast to inorganic light-emitting diodes, OLEDs do not require monocrystalline materials. Compared to LEDs, OLEDs can therefore be produced using inexpensive thin-film technology. As a result, OLEDs make it possible to produce flat light sources which on the one hand have a very thin appearance and, on the other hand, have a particularly homogeneous appearance when used as a luminous surface visible through the lens of a vehicle lamp.

LEDs have a forward voltage, which makes it possible to arrange a plurality of LEDs in series or in series with an LED string and to apply the vehicle electrical system voltage as a supply voltage to the LED string at normal, prevailing in driving operation with the engine running vehicle electrical system voltage. Due to the higher forward voltage of OLEDs, that number of OLEDs which can be connected in series or in series with an OLED strand and which, while maintaining the light emission, makes it possible to apply the vehicle electrical system voltage prevailing when the internal combustion engine is running as the supply voltage to an OLED line with LEDs.

In addition to the described advantages, however, semiconductor light sources have the disadvantage that they do not tend to darken just like conventional light sources due to their functional principle and short reaction time, for example when the electric starter of an internal combustion engine of a vehicle is actuated when the light is on and the vehicle electrical system voltage therefore drops when the voltage applied to them falls below their respective forward voltage or when the vehicle electrical system voltage drops below a minimum supply voltage resulting from the sum of the forward voltages of the semiconductor light sources connected in series with a semiconductor light source train.

This exacerbates the initially described impairment of traffic safety by the increasing replacement of mainly reaction-free, conventional light sources, such as light bulbs, halogen lamps and gas discharge lamps by semiconductor light sources.

In order to counteract this, the number of semiconductor light sources arranged in series with a semiconductor light source strand has been reduced to a number in which the maintenance of an electrical voltage at each of the semiconductor light source voltage is still maintained in the case of, for example, the operation of an electric starter of an internal combustion engine. Strand arranged semiconductor light source is ensured above the forward voltage. To protect against destruction or premature aging by overvoltage in normal, prevailing in the running operation with the internal combustion engine board voltage, semiconductor light sources, such as the mentioned LEDs and / or OLEDs, and / or semiconductor light source strands, such as the mentioned LED strands and / or OLED strands, moreover, hitherto installed in series with current limiters or similarly acting circuit elements which, with normal vehicle electrical system voltage, reduce these to a supply voltage in which they are connected in series Switched semiconductor light sources take no damage, and still allow the operation of the series-connected semiconductor light sources with lowered vehicle electrical system voltage.

The disadvantage of this is that by this optimization to a lowered vehicle electrical system voltage during the majority of driving, during which not a lowered, but normal board voltage prevails, a not inconsiderable part of the electrical system for the operation of legally required for the fulfillment of road traffic light functions provided semiconductor light sources removed and other value to be made available to be lost electrical energy as power loss is lost.

By US 2007/108843 A1 is a power supply of series-connected semiconductor light sources of a vehicle intended for light bulbs known. The power supply includes a constant current source and a bypass switch in parallel with each semiconductor light source and / or each pair of series-connected semiconductor light sources and / or each group of series-connected semiconductor light sources. By opening and closing the respective bypass switch, the individual semiconductor light sources and / or pairs of semiconductor light sources connected in series and / or groups of semiconductor light sources connected in series can be individually illuminated or switched off as required. An electrical control of the bypass switch detects faults of one or more semiconductor light sources and switches off faulty semiconductor light sources by bridging. The electrical control can illuminate redundant semiconductor light sources to replace faulty semiconductor light sources. By pulse width modulation of the opening and closing of the bypass switch, the electrical control can dim one or more semiconductor light sources as needed. During the bypass in certain operating conditions, as would prevail in a vehicle application, for example, with lowered vehicle electrical system voltage, at least a portion of the LEDs remains dark. This is not a satisfactory solution to the described impairment of traffic safety, because a part of the semiconductor light sources of a provided for fulfilling a light function in a vehicle lamp bulb with multiple semiconductor light sources remain dark as light sources with lowered vehicle electrical system voltage and thereby the light emission of the bulb is reduced overall and at least in individual Spatial directions of the whole, of all Semiconductor light sources to be covered together solid angle range is missing. An additional disadvantage also results from the fact that during operation of the lamp with lowered vehicle electrical system voltage, a part of the LEDs remain directly recognizable dark. Furthermore, this represents a waste of resources, at least when the vehicle electrical system voltage is lowered, since a part of the semiconductor light sources installed in the lighting device is not used as light sources.

By US 2013/207548 A1 is a light source with multiple light sources designed as LEDs known. In order to adapt to very different supply voltages, the lighting means may have a current limiter arranged in series with the LEDs, accompanied by the disadvantage of high power loss at high supply voltage. Alternatively or additionally, the lighting means may comprise a microcontroller and activation switches arranged in series with the LEDs and / or bypass switches arranged parallel to one or more of the LEDs. Outputs of the microcontroller open and close the switches to turn the LEDs on when the power supply voltage by closing the activation switch all shut down at too high supply voltage by opening the activation switch or to bridge at low supply voltage by closing the bypass switch part of the LEDs. For this purpose, the microcontroller can compare a detected supply voltage and / or a supply current intensity and / or a temperature with one or more threshold values and, depending thereon, completely disconnect the LEDs from the supply voltage or bypass a portion of the LEDs or switch on all the LEDs. In addition to the mentioned disadvantage of high power loss when using a series-connected current limiter, this is not a satisfactory solution of the described impairment of traffic safety, because a part of the LEDs of a provided for fulfilling a light function in a vehicle lamp bulb with multiple LEDs as light sources with lowered vehicle electrical system voltage dark remain and thus the light emission of the lamp is reduced overall and at least in individual spatial directions of the entire, to be covered by all LEDs together solid angle range is absent. An additional disadvantage also results from the fact that during operation of the lamp with lowered vehicle electrical system voltage, a part of the LEDs remain directly recognizable dark. Moreover, instead of a satisfactory solution, this represents a not inconsiderable waste of resources, since at least in certain areas of the supply voltage at least a portion of the LEDs installed in the light source as light sources is unused.

An alternative is elaborate polarity reversal protection circuits and a selection of the forward voltages of the LEDs in order to operate just three LEDs in series with lowered vehicle electrical system voltage. However, this is associated with additional costs or limited availability of suitable LEDs.

• die Halbleiterlichtquellen der Gruppe in zwei Untergruppen zu jeweils mindestens einer Halbleiterlichtquelle aufgeteilt sind,
• die nach der Aufteilung jeweils einer Untergruppe zugeordneten Halbleiterlichtquellen jeweils in Serie zu je einem Halbleiterlichtquellen-Unterstrang elektrisch verschaltet sind, und
• die beiden Halbleiterlichtquellen-Unterstränge parallel verschaltet sind.

Das Leuchtmittel umfasst Mittel zur Überwachung und Erfassung einer Bordnetzspannung sowie zum Vergleich der überwachten Spannung mit einem Spannungs-Schwellenwert. Das Leuchtmittel umfasst außerdem Mittel zur Umschaltung zwischen den bei normaler Spannung höher als der Spannungs-Schwellenwert in Serie zu einem Halbleiterlichtquellen-Strang angeordneten Halbleiterlichtquellen der Gruppe zu einer Anordnung, bei der:

• bei abgesenkter Spannung niedriger als der Spannungs-Schwellenwert die Halbleiterlichtquellen der Gruppe in zwei Untergruppen zu jeweils mindestens einer Halbleiterlichtquelle aufgeteilt sind,
• die jeweils einer Untergruppe zugeordneten Halbleiterlichtquellen jeweils in Serie zu je einem Halbleiterlichtquellen-Unterstrang verschaltet sind, und
• die beiden Halbleiterlichtquellen-Unterstränge parallel verschaltet sind.

By EP 3 193 563 A1 are known a method for operating a light provided for a vehicle lamp with a group of at least two semiconductor light sources, as well as a suitable for performing the method light source with a group of at least two semiconductor light sources. The method provides a switchover between the semiconductor light sources of the group which are connected at a normal vehicle supply voltage higher than a voltage threshold in series with a semiconductor light source train to form an arrangement in which, with the vehicle electrical system voltage lowered, lower than the voltage threshold value:

• the semiconductor light sources of the group are subdivided into two subgroups to at least one semiconductor light source in each case,
• the semiconductor light sources assigned according to the subdivision of a respective subgroup are in each case electrically connected in series with one semiconductor light source subcord, and
• the two semiconductor light source sub-strings are connected in parallel.

The light-emitting means comprises means for monitoring and detecting a vehicle electrical system voltage and for comparing the monitored voltage with a voltage threshold. The luminous means further comprises means for switching between the semiconductor light sources of the group which are arranged at normal voltage higher than the voltage threshold in series with a semiconductor light source strand to form an arrangement in which:

• when the voltage is lower than the voltage threshold, the semiconductor light sources of the group are divided into two subgroups, each with at least one semiconductor light source,
• each of a subgroup associated semiconductor light sources are each connected in series with each of a semiconductor light source sub-string, and
• the two semiconductor light source sub-strings are connected in parallel.

This method and this illuminant are practical for a few LEDs in which no failure must be detected and have the advantage of a manageable effort for the circuit structure. The disadvantage of this is that due to the high efficiency of semiconductor light sources associated with their low power consumption is not possible to detect a failure of one or more semiconductor light sources by means of an on-board controller, for example, to indicate the failure and / or replacement at the next inspection date the driver.

It is an object of the invention to develop a method for operating a luminous means with a plurality of semiconductor light sources and a corresponding luminous means suitable for carrying out such a method, which enable a low power loss with simultaneously high resource utilization with a high contribution to traffic safety.

The object is achieved in each case by the features of the independent claims. Advantageous embodiments are set forth in the claims, the drawings and the following description, including those associated with the drawings.

The invention provides to increase the efficiency associated with the possibility of detecting the failure of one or more semiconductor light sources, such as LEDs before, two or more circuit blocks, each consisting of a linear current source or an LED driver and a connected thereto and supplied with power semiconductor light sources -Strang of two or more series-connected semiconductor light sources, in particular LEDs, parallel with lowered vehicle electrical system voltage and at short also called nominal voltage normal vehicle electrical system voltage in series.

Therefore, a linear current source, also referred to as an LED driver, is used for at least two, advantageously for a number of, series-connected semiconductor light sources, such as LEDs, which number of semiconductor light sources, such as LEDs with lowered, for example minimal on-board voltage, in series with the LED. Driver can be supplied.

The at least two series-arranged semiconductor light sources are referred to in the context of the invention as a semiconductor light source strand.

In contrast, a semiconductor light source group, also referred to as a circuit block or a short block, in the context of the invention designates a linear current source having a semiconductor light source strand connected thereto or a linear current source having a plurality of semiconductor light source strands connected in parallel thereto. A semiconductor light source group hereinafter comprises the linear current source and at least one semiconductor light source strand connected thereto.

When briefly also referred to as nominal voltage normal vehicle electrical system voltage, for example when the generator is running, results from the previously described arrangement of two supplied by a linear power source or connected to this and arranged in series semiconductor light sources without further measures, a poor efficiency.

In order to counteract this, the invention also provides for switching at least two semiconductor light source groups in series at nominal voltage, which increases the efficiency.

When the vehicle electrical system voltage is lowered, however, the invention provides for the at least two semiconductor light source groups to be switched in parallel, whereby all the semiconductor light sources of the light source are operated when the vehicle electrical system voltage is lowered.

By virtue of the fact that each semiconductor light source group comprises a linear current source, it is possible for the failure of individual semiconductor light sources, such as LEDs of the luminous means, to be detected.

The invention thus eliminates the disadvantages of the prior art by a variable interconnection of the circuit blocks from parallel to serial and vice versa.

Advantages result from maintaining the possibility of detecting the failure of individual or a plurality of semiconductor light sources, in particular LEDs, by means of the LED driver, accompanied by high efficiency and low power dissipation and avoiding flickering of a realized by semiconductor light sources such as LEDs light function in vehicles with start -Stop automatic.

Further advantages result from a simple scalability due to the modular construction of circuit blocks.

Additional advantages result from the availability of standard components for powering semiconductor light sources, such as LEDs.

A first subject of the invention accordingly relates to a method for operating a luminous means provided for a vehicle luminaire with a plurality of semiconductor light sources.

The method provides, at least two semiconductor light source groups each having at least one semiconductor light source strand of at least two series-arranged semiconductor light sources, but at most each one of the number of semiconductor light sources operable at minimum prevailing vehicle voltage in number corresponding number of semiconductor light sources corresponding number of semiconductor light sources arranged in series form.

In order to reduce the electrical control performance and thus also the electrical power loss, it makes sense to connect as many semiconductor light sources as possible in series, wherein the number of the maximum electrically arranged in a row semiconductor light sources, such as LEDs or OLEDs, is predetermined by the minimal prevailing vehicle electrical system voltage ,

By arranging in each case a number of semiconductor light sources per semiconductor light source group which can be operated in series at a minimal prevailing vehicle supply voltage, the operation of the semiconductor light sources within the semiconductor light source groups can be ensured even when the vehicle electrical system voltage is lowered.

Each semiconductor light source group may include one or more semiconductor light source strands arranged in parallel in this case within the semiconductor light source group.

The method also provides for providing each semiconductor light source group with a linear current source, also referred to as a semiconductor light source driver, to which the at least one semiconductor light source strand of the corresponding semiconductor light source group is connected.

As a result, a failure of one or more semiconductor light sources per semiconductor light source group can be detected.

In addition, the method provides detection of the vehicle electrical system voltage of a vehicle equipped with the vehicle lamp and the comparison of the detected vehicle electrical system voltage with a voltage threshold.

The method now envisages, in the case of a normal vehicle electrical system voltage higher than the voltage threshold value, to connect two or more semiconductor light source groups, each comprising a linear current source, in series with a semiconductor light source group line.

The method also provides a switching between the normal vehicle electrical system voltage higher than the voltage threshold in series with a semiconductor light source group strand interconnected semiconductor light source groups to an arrangement in which when the vehicle electrical system voltage lower than the voltage threshold each one Linear power source comprising semiconductor light source groups of the semiconductor light source group strand are connected in parallel.

The arrangement of a linear current source per semiconductor light source group as well as the limitation of an arrangement within each semiconductor light source group in each case one of the number of semiconductor light sources operable in series with minimal prevailing vehicle supply voltage means a number of semiconductor light sources in series with a semiconductor light source strand all semiconductor light sources of a semiconductor light source group met with minimal prevailing vehicle electrical system voltage.

By connecting two or more semiconductor light source groups in series to a semiconductor light source group strand at normal vehicle electrical system voltage higher than the voltage threshold resulting in normal driving conditions a reduction in power loss compared to maintaining the lowered vehicle electrical system voltage lower than the voltage Threshold prevailing arrangement above the voltage threshold.

A second subject of the invention relates to a luminaire provided with a plurality of semiconductor light sources for a vehicle lamp.

The luminous means comprises at least two semiconductor light source groups, each consisting of a linear current source and at least one semiconductor light source strand connected to the linear current source, comprising at least two semiconductor light sources arranged in series.

For each semiconductor light source group, a plurality of semiconductor light source strands can be connected in parallel to one another to the linear current source of the semiconductor light source group and can be supplied or supplied with power by the latter.

In addition, the luminous means comprises comparison means for comparing a vehicle power supply voltage that supplies the power supply of the luminous means with a voltage threshold value.

In addition, the lighting means comprises switching means connected to the comparison means for switching between an arrangement in which, with normal vehicle electrical system voltage higher than the voltage threshold, two or more semiconductor light source groups each comprising a linear current source are arranged in series with a semiconductor light source group train Arrangement in which, when the vehicle electrical system voltage is lower than the voltage threshold value, the respective semiconductor light source groups of the semiconductor light source group string which each comprise a linear current source are connected in parallel.

A linear current source is a current source whose characteristic curve reflects the current emitted by it above the voltage applied at its connection points in a current-voltage diagram of a line with a negative gradient. It can be described in the equivalent circuit diagram as an ideal current source with an internal resistance in parallel.

The number of semiconductor light sources per semiconductor light source strand can correspond in each case to one of the number of semiconductor light sources which can be operated in series with minimal prevailing vehicle supply voltage.

It can be seen that the invention provides for the object, also groups called groups of semiconductor light sources, such as LEDs and / or OLEDs, and to interconnect each with a linear current source, such as an LED driver, so that the semiconductor light sources of the blocks operate at minimum voltage. Thus, these blocks can be operated in parallel with minimum vehicle electrical system voltage. At rated voltage, the blocks are switched in series. Thus all functions of the linear current sources, such as a failure detection of individual semiconductor light sources of the blocks are available.

In vehicle applications, usually only LED strings with two LEDs are feasible because the minimum prevailing vehicle electrical system voltage is about 7V. However, the normal vehicle electrical system voltage prevailing during driving is 13.5V and thus makes it possible to connect four LEDs in series.

The invention allows the switching of, for example, two LED blocks with LED strings with two LEDs in series. By assigning one linear current source to each block, the full range of functions of the LED driver is available, such as failure detection.

Further advantages over the prior art are that standard components can be used. These can be optimally thermally operated, for example in order to reduce the required board area or to save cooling plates.

Additional advantages include a simple way of scaling and opening the possibility to use the functions that are included in an LED driver, in particular the failure detection.

The lighting means may comprise individual or a combination of the features described above and / or subsequently in connection with the method, just as the method may comprise and / or implement individual or a combination of a plurality of features previously and / or subsequently described in connection with the lighting means.

Both the illuminant and, alternatively or additionally, the method may alternatively or additionally comprise one or a combination of several in the context of the prior art and / or in one or more of the documents mentioned in the prior art and / or in the following description the In the embodiments illustrated in the drawings have features described.

Additional advantages over the prior art that go beyond the complete solution of the problem set and / or the advantages mentioned above for the individual features are listed below.

Fig. 1

eine Schaltungsanordnung eines erfindungsgemäßen Leuchtmittels mit parallel angeordneten LED-Treibersträngen bei abgesenkter Bordnetzspannung.

Fig. 2

eine Schaltungsanordnung eines erfindungsgemäßen Leuchtmittels mit in Serie angeordneten LED-Treibersträngen bei normaler Bordnetzspannung.

Fig. 3

ein Ablaufdiagramm eines Verfahrens zum Betrieb eines für eine Fahrzeugleuchte vorgesehenen Leuchtmittels mit mehreren Halbleiterlichtquellen.

The invention will be explained in more detail with reference to embodiments shown in the drawings. The proportions of the individual elements to one another in the figures do not always correspond to the actual size ratios, since some shapes are simplified and other shapes are shown enlarged in relation to other elements for better illustration. For identical or equivalent elements of the invention, identical reference numerals are used. Furthermore, for the sake of clarity, only reference symbols are shown in the individual figures, which are required for the description of the respective figure. The illustrated embodiments are only examples of how the invention may be configured and are not an exhaustive limitation. In a schematic representation:

Fig. 1

a circuit arrangement of a luminous means according to the invention with parallel LED driver strings with lowered vehicle electrical system voltage.

Fig. 2

a circuit arrangement of a luminous means according to the invention with arranged in series LED driver strings at normal vehicle electrical system voltage.

Fig. 3

a flowchart of a method for operating a light provided for a vehicle lamp with a plurality of semiconductor light sources.

An in Fig. 3 in its process illustrated method for operating a light bulb provided for a vehicle lamp 01 with a plurality of semiconductor light sources 02, the circuit arrangement with lowered vehicle electrical system voltage in Fig. 1 , And its circuit arrangement at normal vehicle electrical system voltage in Fig. 2 is shown in whole or in part, sees in a first method step I, the formation of at least two semiconductor light source groups 03, each with a linear current source 04 and At least one connected to this semiconductor light source strand 05 from each at least two series-arranged semiconductor light sources 02 before.

At least two semiconductor light sources 02 arranged in series are referred to here as a semiconductor light source strand 05.

On the other hand, a semiconductor light source group 03, also referred to as a circuit block or a short block, denotes a linear current source 04 with a semiconductor light source strand 05 connected to it or a linear current source 04 with a plurality of semiconductor light source strands 05 connected parallel to one another. A group of semiconductor light sources 03 comprises the following Linear current source 04 and at least one connected to this semiconductor light source strand 05th

A linear current source 04 is a current source whose characteristic curve reflects the current emitted by it above the voltage present at its connection points in a current-voltage diagram of a line with a negative gradient. It can be described in the equivalent circuit diagram as an ideal current source with an internal resistance in parallel.

In a second method step II following the first method step I, the method provides for the detection of a vehicle electrical system voltage U of a vehicle equipped with the vehicle lamp 01.

One of the vehicle electrical system voltage U proportional supply voltage U ₀ serves the operation of the lamp 01. This supply voltage U ₀ may be equal to the vehicle electrical system voltage U.

In a subsequent to the second step II process step III, the method provides for the comparison of the detected vehicle electrical system voltage U with a voltage threshold U _S before.

If the result of the comparison carried out in the third method step III that the recorded vehicle electrical system voltage U is higher than the voltage threshold value U _S , then there is a normal vehicle electrical system voltage.

In the case of the presence of normal vehicle electrical system voltage as a result of the comparison carried out in the third method step III, the method then looks at one the third step III following fourth step IV a schematically in Fig. 2 shown interconnection of at least two each a linear current source 04 comprehensive semiconductor light source groups 03 in series with a semiconductor light source group strand 06 before.

The interconnection of two or more of a respective linear current source 04 comprehensive semiconductor light source groups 03 in series with a semiconductor light source group strand 06 is thus according to the method in the fourth step IV at a normal vehicle electrical system voltage U higher than the voltage threshold U _S.

The method can be hereafter as in Fig. 3 indicated by an arrow A again be repeated from the second process step II, for example, as long as a vehicle equipped with at least one corresponding illuminant 01 vehicle lamp is in operation and / or realized by a corresponding light source 01 light function of a vehicle lamp is needed , This can be done for example by querying a position of an ignition key and / or the position of a corresponding light function activating switch.

If the result of the comparison carried out in the third method step III that the recorded vehicle electrical system voltage U is lower than the voltage threshold value U _S , then there is a lowered vehicle electrical system voltage.

In the case of the presence of lowered vehicle electrical system voltage as a result of the comparison carried out in the third method step III, the method, however, sees in a subsequent to the third step III fifth method step V switching between the normal vehicle electrical system voltage higher than the voltage threshold U _S as in Fig. 2 shown schematically in series with a semiconductor light source group strand 06 interconnected semiconductor light source groups 03 to a in Fig. 1 schematically shown arrangement in which the respective one linear current source 04 comprehensive semiconductor light source groups 03 of the semiconductor light source group string 06 are connected in parallel.

The interconnection of the at least two each comprising a linear current source 04 and at normal vehicle electrical system voltage higher than the voltage threshold U _S as in Fig. 2 shown schematically in series with a Semiconductor light source group string 06 interconnected semiconductor light source groups 03 parallel to each other, as shown in Fig. 1 is shown schematically, accordingly takes place according to the method in the fifth step V at a lowered vehicle electrical system voltage U lower than the voltage threshold U _S.

The method can be hereafter as in Fig. 3 indicated by an arrow B again be repeated from the second method step II, for example, as long as a vehicle equipped with at least one corresponding illuminant 01 vehicle lamp in operation and / or realized by a corresponding light source 01 light function of a vehicle lamp is needed , This can be done for example by querying a position of an ignition key and / or the position of a corresponding light function activating switch.

Accordingly, the method for operating a light source 01 provided with a plurality of semiconductor light sources 02 for a vehicle light provides for forming at least two semiconductor light source groups 03 each having at least one semiconductor light source strand 05 of at least two semiconductor light sources 02 arranged in series.

The method further provides for each semiconductor light source group 03 to be provided with a linear current source 04, also referred to as semiconductor light source driver, to which the at least one semiconductor light source strand 05 of the corresponding semiconductor light source group 03 is connected.

In addition, the method provides detection of the vehicle electrical system voltage U of a vehicle equipped with the corresponding illuminant 01 comprising a vehicle lamp and the comparison of the detected vehicle electrical system voltage U with a voltage threshold value U _S.

The method provides, with normal vehicle electrical system voltage higher than the voltage threshold value U _S, to connect two or more semiconductor light source groups 03, each comprising a linear current source 04, in series with a semiconductor light source group line 06.

In addition, the method provides a switchover between the semiconductor light source groups 03, which are interconnected at a normal vehicle electrical system voltage higher than the voltage threshold value U _S in series with a semiconductor light source group 06, to an arrangement in which, when the vehicle electrical system voltage is lower than the voltage voltage. Threshold value U _S, the respective semiconductor power source groups 03 of the semiconductor light source group string 06 comprising a linear current source 04 are connected in parallel.

By switching between two or more at normal vehicle electrical system voltage to a semiconductor light source group string 06 arranged in series semiconductor light source groups 03 to a parallel arrangement of the semiconductor light source groups 03 with lowered vehicle electrical system voltage all semiconductor light sources 02 of the lamp 01 under all operating conditions of the vehicle, in particular Even when the automatic start-stop system is switched on, it can be operated reliably.

By connecting two or more semiconductor light source groups 03 in series with a semiconductor light source group string 06 at normal vehicle electrical system voltage higher than the voltage threshold U _S results in normal driving conditions a reduction in power loss compared to maintaining the lowered vehicle electrical system voltage lower than the voltage threshold U _S prevailing arrangement above the voltage threshold U _S.

By virtue of the linear current source 04 provided in each semiconductor light source group 03, a failure of one or more semiconductor light sources 02 per semiconductor light source group 03 can be detected.

The method can provide that the semiconductor light source strands 05 of the semiconductor light source groups 03 are each formed from one of the number of semiconductor light sources 02 which can be operated in series at a minimal prevailing vehicle supply voltage.

In order to reduce the electrical control performance and thus also the electrical power loss, it makes sense to connect as many semiconductor light sources 02 as possible in series, wherein the number of the maximum electrically arranged in a row Semiconductor light sources 02, such as LEDs or OLEDs, is predetermined by the minimum prevailing vehicle electrical system voltage.

By arranging in each case a number of semiconductor light sources 02 per semiconductor light source group 03, which can be operated in series at a minimal prevailing vehicle voltage, the operation of the semiconductor light sources 02 within the semiconductor light source groups 03 can be ensured even when the vehicle electrical system voltage is lowered.

By arranging a linear current source 04 per semiconductor light source group 03 and by restricting an arrangement within each semiconductor light source group 03 one of the minimum number of onboard electrical system voltage operable in series number of semiconductor light sources 02 corresponding number of semiconductor light sources 02 in series with a semiconductor light source strand 05th the requirement for operability of all semiconductor light sources 02 of a semiconductor light source group 03 is met with a minimal prevailing vehicle electrical system voltage.

The method may alternatively or additionally provide that each semiconductor light source group 03 comprises one or more semiconductor light source strands 05 connected in parallel to the linear current source 04 in this case within the semiconductor light source group 03, as shown in FIG Fig. 1 and Fig. 2 is shown schematically.

A previously described method can be achieved by a suitable for carrying out a method described above lamp 01 for a vehicle lamp, the circuit arrangement with lowered vehicle electrical system voltage in Fig. 1 , And its circuit arrangement at normal vehicle electrical system voltage in Fig. 2 shown in whole or in part, be realized.

A vehicle lamp for which a corresponding illuminant 01 can be provided comprises, for example, a luminaire interior substantially enclosed by a luminaire housing and a lens and at least one illuminant for at least one light function of the vehicle luminaire housed therein and comprising at least one light source.

Each vehicle lamp fulfills one or more tasks or functions depending on the design. To fulfill each task or function, a light function of the vehicle lamp is provided. Light functions are, for example, in a configuration as a headlamp a function illuminating the road surface, or in a configuration as a signal light, a signal function, such as a Wiederblinklichtfunktion to the direction indicator or a brake light function to indicate a braking action, or. a limiting light function, such as a taillight function, to ensure visibility of the vehicle during the day and / or night, such as in a taillight or daytime running light configuration. Examples of vehicle lights are the Fahrzeugbug, on the vehicle flanks and / or on the side mirrors arranged flashing lights, exit lights, such as ambient lighting, marker lights, brake lights, fog lamps, reversing lights, and typically high set third brake lights, so-called Central, High-Mounted Braking lights, daytime running lights, headlamps and fog lights used as turning or cornering lights, as well as combinations thereof.

Each light function must fulfill an example prescribed by law light distribution. The light distribution sets at least to be observed, colloquially known as brightness luminous flux in at least to be observed solid angle ranges.

For the individual lighting functions, there are sometimes different brightnesses or visibility ranges and, in some cases, different light colors.

At least one light source of the luminous means of a vehicle lamp can be assigned one or more optical elements contributing to the shaping of a light distribution for directing the light.

The lens is formed by a transparent cover which is usually made of a plastic material today, which closes off the interior of the lamp and protects the components housed therein, such as one or more lamps, reflectors and alternatively or additionally provided optical elements against the effects of weathering.

The luminaire housing or the interior of the luminaire can be subdivided into a plurality of chambers, each with its own light sources and / or illuminants and / or optical elements and, if appropriate, light disks, of which several chambers can be identical and / or each chamber can fulfill a different lighting function.

The optical elements mentioned can be at least one reflector and / or at least one lens and / or one or more optical disks or the like arranged in the beam path between at least one light source of the luminous means and the light disk.

For example, at least one reflector arranged behind at least one light source of at least one luminous means can be accommodated in the luminaire interior. The reflector may be formed at least in part by a separate component and / or by at least one part of the luminaire housing itself, for example by means of an at least partially reflective coating.

The lens itself may alternatively or additionally be formed as an optical element, for example by being preferably provided on the inside with an optical structure contributing to the production of one or more light distributions mentioned above. This may possibly be dispensed with an optical disk.

Examples of vehicle lights are the Fahrzeugbug, on the vehicle flanks and / or on the side mirrors and arranged at the rear of vehicle rear lights, exit lights, such as ambient lighting, marker lights, brake lights, fog lamps, reversing lights, and typically high set third brake lights, so-called Central, High-Mounted Braking lights, daytime running lights, headlamps and fog lights used as turning or cornering lights, as well as combinations thereof.

Such a combination is realized, for example, regularly in the known taillights. These include, for example, repeating flashing lights, marker lights, brake lights, fog lights and reversing lights are used to name just one of many realized in tail lights combinations. Neither does this enumeration claim to be complete, nor does this mean that in a tail light all the aforementioned lights must be combined. So For example, only two or three of the mentioned or else other luminaires can be combined with one another in a common luminaire housing of a taillight.

• mindestens zwei Halbleiterlichtquellen-Gruppen 03 mit jeweils einer Linearstromquelle 04 und mindestens einem an die Linearstromquelle 04 angeschlossenen Halbleiterlichtquellen-Strang 05 mit wenigstens zwei in Serie angeordneten Halbleiterlichtquellen 02,
• Vergleichsmittel zum Vergleich einer Bordnetzspannung U eines die Stromversorgung des Leuchtmittels 01 besorgenden Bordnetzes eines mit einer entsprechenden Fahrzeugleuchte ausgestatteten Fahrzeugs mit einem Spannungs-Schwellenwert U_S, und
• mit den Vergleichsmitteln verbundene Schaltungsmittel zur Umschaltung zwischen einer in Fig. 2 in ihrem Schaltungsaufbau prinzipiell dargestellten Anordnung, bei der bei normaler Bordnetzspannung höher als der Spannungs-Schwellenwert U_S zwei oder mehr jeweils eine Linearstromquelle 04 umfassende Halbleiterlichtquellen-Gruppen 03 in Serie zu einem Halbleiterlichtquellen-Gruppen-Strang 06 angeordnet sind, zu einer in Fig. 1 in ihrem Schaltungsaufbau prinzipiell dargestellten Anordnung, bei der bei abgesenkter Bordnetzspannung niedriger als der Spannungs-Schwellenwert U_S die jeweils eine Linearstromquelle 04 umfassenden Halbleiterlichtquellen-Gruppen 03 des Halbleiterlichtquellen-Gruppen-Strangs 06 parallel verschaltet sind.

A in its circuit arrangement with lowered vehicle electrical system voltage in Fig. 1 , and in its circuit arrangement with normal vehicle electrical system voltage in Fig. 2 Wholly or partially illustrated illuminant 01 with a plurality of semiconductor light sources 02 for a vehicle lamp comprises:

• at least two semiconductor light source groups 03 each having a linear current source 04 and at least one semiconductor light source strand 05 connected to the linear current source 04 with at least two semiconductor light sources 02 arranged in series,
• Comparative means for comparing a vehicle electrical system voltage U of the power supply of the illuminant 01 on-board electrical system of a vehicle equipped with a corresponding vehicle lamp with a voltage threshold U _S , and
• switching means connected to the comparison means for switching between an in Fig. 2 in its circuit configuration illustrated in principle, in which at normal vehicle electrical system voltage higher than the voltage threshold U _S two or more each a linear current source 04 comprehensive semiconductor light source groups 03 are arranged in series with a semiconductor light source group string 06, to a in Fig. 1 in its circuit structure illustrated in principle arrangement, in which with lowered vehicle electrical system voltage lower than the voltage threshold U _S, the respective one linear current source 04 comprehensive semiconductor light source groups 03 of the semiconductor light source group string 06 are connected in parallel.

Accordingly, the light source 01 provided with a plurality of semiconductor light sources 02 for a vehicle lamp comprises at least two semiconductor light source groups 03 consisting of in each case one linear current source 04 and at least one semiconductor light source string 05 connected to the linear current source 04 from at least two semiconductor light sources 02 arranged in series.

In addition, the illuminant 01 comprises comparing means for comparing a vehicle electrical system voltage which supplies the power supply of the illuminant 01 with a voltage threshold value.

In addition, the illuminant 01 comprises switching means connected to the comparison means for switching between an arrangement in which, with normal vehicle electrical system voltage higher than the voltage threshold U _S, two or more semiconductor light source groups 03 each comprising a linear current source 04 are connected in series with a semiconductor light source group train are arranged 06 to an arrangement in which at a reduced board voltage lower than the voltage threshold value U _S at ordinary board voltage higher than the voltage threshold value U _S-connected to the semiconductor light source groups strand 06 and are each a linear current source 04 comprising Halbleiterlichtquellen- Groups 03 are connected in parallel, or at least two of the normal vehicle electrical system voltage higher than the voltage threshold U _S to the semiconductor light source group string 06 interconnected and each comprising a linear current source 04 comprising semiconductor light source groups 03 parallel versch are old.

The number of semiconductor light sources 02 per semiconductor light source strand 05 can correspond in each case to one of the number of semiconductor light sources 02 that can be operated in series with a minimal prevailing vehicle electrical system voltage.

Depending semiconductor light source group 03, a plurality of semiconductor light source strands 05 can be connected parallel to each other to the linear current source 04 of the semiconductor light source group 03 and supplied by this with power or be supplied, as in a by the in Fig. 1 and Fig. 2 shown schematically diagrams 01 is the case.

It is important to emphasize that the semiconductor light sources 02 of the luminous means 01 can be similar semiconductor light sources 02 or different semiconductor light sources 02.

For example, at least one of the semiconductor light sources 02 may be an LED.

In principle, all semiconductor light sources 02 may also be LEDs.

For example, at least one of the semiconductor light sources 02 may be an OLED.

In principle, all semiconductor light sources 02 can also be OLEDs.

In summary, the invention provides for increasing the efficiency associated with the possibility of detecting the failure of one or more semiconductor light sources 02, such as LEDs before, two or more briefly referred to as circuit blocks semiconductor light source groups 03, each consisting of a designated as an LED driver linear current source 04 and a connected thereto and supplied with power semiconductor light source strand 05 of two or more series-connected semiconductor light sources 02, in particular LEDs, with lowered vehicle electrical system voltage in parallel and at short also called nominal voltage normal vehicle electrical system voltage in series.

Therefore, a linear current source, also referred to as an LED driver, is used for at least two, advantageously for a number of series-connected semiconductor light sources 02, such as LEDs, which number of semiconductor light sources 02, such as LEDs with lowered, for example minimal on-board voltage in series with the LED driver can be powered.

When briefly also called rated voltage normal vehicle electrical system voltage, for example, when the generator, resulting from an arrangement of two supplied by a linear current source 04 or connected to these and arranged in series semiconductor light sources 02 without further measures, a poor efficiency.

In order to counteract this, the invention provides for switching at least two semiconductor light source groups 03 in series at nominal voltage, which increases the efficiency.

When lowered vehicle electrical system voltage, however, the invention provides to switch the at least two semiconductor light source groups 03 in parallel, whereby at lowered vehicle electrical system voltage all semiconductor light sources 02 of the light source 01 are operated.

Because each semiconductor light source group 03 comprises a linear current source 04, it is possible for the failure of individual semiconductor light sources 02, such as LEDs of the light source 01, to be detected.

The invention thus eliminates the disadvantages of the prior art by a variable interconnection of the circuit blocks from parallel to serial and vice versa.

Advantages result from maintaining the possibility of detection of the failure of individual or a plurality of semiconductor light sources 02, in particular LEDs, by means of the LED driver, accompanied by high efficiency and low power dissipation, and avoiding flickering of a light function realized by semiconductor light sources 02, such as LEDs Vehicles with automatic start-stop.

Further advantages result from a simple scalability due to the modular construction of circuit blocks.

Additional advantages result from the availability of standard components for the power supply of semiconductor light sources 02, such as LEDs.

It can be seen that the invention provides for the object, also as blocks or circuit blocks designated groups of semiconductor light sources 02, such as LEDs and / or OLEDs to form, and to interconnect each with a linear current source 04, for example an LED driver so that the semiconductor light sources 02 of the blocks function at minimum voltage. Thus, these blocks can be operated in parallel with minimum vehicle electrical system voltage. At rated voltage, the blocks are switched in series. Thus, all functions of the linear current sources 04, such as a failure detection of individual semiconductor light sources of the blocks are available.

In vehicle applications, usually only LED strings with two LEDs are feasible because the minimum prevailing vehicle electrical system voltage is about 7V. However, the normal vehicle electrical system voltage prevailing during driving is 13.5V and thus makes it possible to connect four LEDs in series.

The invention allows the switching of, for example, two LED blocks with LED strings with two LEDs in series. By assigning a respective linear current source 04 to each block, the full range of functions of the LED driver is available, such as a failure detection.

Further advantages over the prior art are that standard components can be used. These can be optimally thermally operated, for example in order to reduce the required board area or to save cooling plates.

Additional advantages include a simple way of scaling and opening the possibility to use the functions that are included in an LED driver, in particular the failure detection.

The illuminant 01 and / or the method may alternatively or additionally comprise individual or a combination of several in the context of the prior art and / or in one or more of the documents mentioned in the prior art and / or features mentioned in the preceding description.

The luminous means 01 may comprise individual or a combination of the features described above and / or subsequently in connection with the method, just as the method may comprise and / or realize individual or a combination of a plurality of features previously and / or subsequently described in connection with the luminous means 01 can.

The invention is not limited by the description with reference to the embodiments. Rather, the invention encompasses any novel feature as well as any combination of features, including in particular any combination of features in the claims, even if that feature or combination itself is not explicitly stated in the claims or embodiments.

The invention is particularly industrially applicable in the field of manufacturing vehicle lights, in particular motor vehicle lights.

The invention has been described with reference to preferred embodiments. However, it is conceivable for a person skilled in the art that modifications or Changes of the invention can be made without departing from the scope of the following claims.

LIST OF REFERENCE NUMBERS

01

vehicle light

02

Semiconductor light source

03

Semiconductor light sources group

04

Linear power supply

05

Semiconductor light sources strand

06

Semiconductor light source groups strand

U

Board supply voltage

U ₀

supply voltage

I

step

II

step

III

step

IV

step

V

step

A

arrow

B

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Claims (8)

Method for operating a light source (01) provided with a vehicle light with a plurality of semiconductor light sources (02), comprising the method steps: Formation of at least two semiconductor light source groups (03), each with a linear current source (04) and at least one semiconductor light source strand (05) connected thereto, each comprising at least two semiconductor light sources (02) arranged in series, Detecting a vehicle electrical system voltage (U) of a vehicle equipped with the vehicle lamp, Comparison of the recorded vehicle electrical system voltage (U) with a voltage threshold value (U _S ), - Connection of at least two semiconductor light source groups (03) in series with a semiconductor light source group strand (06) at a normal vehicle electrical system voltage higher than the voltage threshold (U _S ), and - Switching between the normal vehicle electrical system voltage higher than the voltage threshold (U _S ) in series with a semiconductor light source group strand (06) interconnected semiconductor light source groups (03) to an arrangement in which the semiconductor light source groups (03) in parallel are interconnected, at a lowered vehicle electrical system voltage lower than the voltage threshold (U _S ). Method according to Claim 1, wherein the semiconductor light source strands (05) of the semiconductor light source groups (03) are each formed from one of a number of semiconductor light sources (02) arranged in series corresponding to a number of semiconductor light sources (02) which can be operated in series at a minimal prevailing vehicle supply voltage. The method of claim 1 or 2, wherein each semiconductor light source group (03) one or more in this case within the semiconductor light source group (03) in parallel to the linear power source (04) connected semiconductor light source strands (05). Light source (01) with a plurality of semiconductor light sources (02) for a vehicle lamp, comprising: at least two semiconductor light source groups (03) each having a linear current source (04) and at least one semiconductor light source strand (05) connected thereto with at least two semiconductor light sources (02) arranged in series, - Comparison means for comparing a vehicle electrical system voltage (U) with a voltage threshold (U _S ), and connected to the comparison means switching means for switching between an arrangement in which at normal vehicle electrical system voltage higher than the voltage threshold (U _S ) at least two semiconductor light source groups (03) are arranged in series with a semiconductor light source group strand (06) to an arrangement in which, when the vehicle electrical system voltage is lower than the voltage threshold value (U _S ), the semiconductor light source groups (03) of the semiconductor light source group line (06) are connected in parallel. Illuminant according to Claim 4, wherein the number of semiconductor light sources (02) per semiconductor light source strand (05) corresponds in each case to one of the number of semiconductor light sources (02) which can be operated in series at a minimal prevailing vehicle supply voltage. Illuminant according to claim 4 or 5, wherein each semiconductor light source group (03) a plurality of semiconductor light source strands (05) parallel to each other to the linear current source (04) of the semiconductor light source group (03) connected and powered by these with electricity and / or supplied. Illuminant according to claim 4, 5 or 6, wherein at least one of the semiconductor light sources (02) is an LED. Illuminant according to one of claims 4 to 7, wherein it is at least one of the semiconductor light sources (02) is an OLED.

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