EP2658349A1 - Planar LED light - Google Patents

Abstract

The fluorescent light has a LED module on which two LEDs (1) are arranged with series or parallel connection in two-dimensional array. The LEDs are connected with a resistor (2) and a switch (3) such that the change of the lights of the LEDs is possible. A constant current source is provided for supplying current to the LEDs. A control unit is provided to control the switch. The white LEDs and multi-color LEDs are used.

Description

The present invention relates to a surface light, with at least one LED module, on which at least two LEDs are arranged in a one- or two-dimensional series and / or parallel connection.

Area lights are designed to emit light over a larger area. For this purpose, surface lights, for example, LEDs, which can be arranged on LED modules. The arrangement of the LEDs on an LED module is usually in a one- or two-dimensional array with a series and / or parallel connection of the LEDs.

Such an arrangement or interconnection can be exemplified by FIG. 1 be removed. Here, three parallel and interconnected LED strings are provided, which are all connected in common to a constant current source 4. In each LED strand several arranged in series or series or interconnected LEDs are provided. At the in FIG. 1 schematically shown LED module as part of a surface light accordingly the LEDs 1 are arranged in a combined series and parallel connection.

Like the arrangement in FIG. 1 can be removed, such surface lights are designed so that the areally arranged LEDs 1 are all operated in the same way, which usually comes for all LEDs 1 and the same type is used. Accordingly, results in the in FIG. 1 shown arrangement that the current provided by the constant current source 4 available evenly distributed to all LED strands, which flows through all the LEDs 1, the same current, so they all shine almost the same bright. Thus, for example, the representation of a manufacturer's logo or other image by the LEDs is not possible.

In particular, but the representation of a manufacturer's logo for a certain period, for example when turning on the surface light, would be quite useful since such surface lights are often mounted on ceilings and thus usually only by the user can be assigned to a manufacturer via the design. Although there are often corresponding manufacturer logos on the housings on panel lights, these are usually difficult to recognize in the installed and mounted state, as a result of which the corresponding representation of the brand of luminaire is scarcely possible.

The aforementioned surface lights are to be distinguished from so-called. Media lights, in which there is also a planar arrangement of controllable LEDs. Such media lights are now basically suitable for the representation of corresponding manufacturer logos or other images. However, it should be noted that in comparison to the surface lights presented above, a completely different interconnection of the LEDs takes place, since each LED can be controlled individually and adjusted in terms of brightness and / or color, which is why such media lights in the broader sense compared with a coarse screen can be. Due to the individual control of each LED with respect to its brightness and / or color, however, results in a considerably greater effort in the wiring or wiring of the LEDs compared to corresponding area lights.

Accordingly, the object of the present invention is to further develop the surface light sketched above in such a way that a representation of a logo or an image is possible while maintaining the one- or two-dimensional series and / or parallel connection of the LEDs.

The object is achieved by a surface light according to claim 1. Advantageous developments of the invention are the subject of the dependent claims.

According to the invention, a surface light with at least one LED module is proposed, wherein at least two LEDs are arranged in a one- or two-dimensional series and / or parallel circuit on the LED module. In addition, it is now provided that at least a part of the LEDs arranged on the LED module means are assigned, which allow a change in the currents flowing through the LEDs.

Preferably, each LED can be assigned to change means, in which case each LED means can be assigned to change.

In this case, the means for changing the dimming of the LEDs allow. Advantageously, the means for changing but also allow bridging the LEDs, which may then, for example, the means for changing a switch and a parallel to one LED or multiple LEDs arranged resistor. The switch is arranged and designed such that, depending on the switching state, the current provided by a constant current source flows either through the LED or LEDs or through the resistor. The constant current source serves to supply the LEDs with electricity.

Due to the configuration according to the invention, that a change in the currents flowing through the LEDs, for example by bridging, is possible in the LEDs, there is now the possibility that individual or even several LEDs can be activated or deactivated independently of the other LEDs. In contrast to the so-called media lights, however, it is still envisaged that the LEDs are arranged in one or two-dimensional series and / or parallel circuits on the LED module and thus need not be individually controlled by a correspondingly complex interconnection. In the case of media luminaires, the LEDs are accordingly individually controlled, whereas in the solution according to the invention, means are provided for modifying the currents flowing through the LEDs, which are assigned to the LEDs.

Furthermore, it can be provided that the LED module has a control unit for controlling the means for altering, wherein control information is stored in the control unit and the control unit is adapted to control the means for changing such that they are either in a normal mode or in a display mode, wherein, in the normal mode, the currents flowing through the LEDs are substantially unaltered by the means for variation, and in the display mode, the currents flowing through the LEDs are changed according to the control information.

Here, in the display mode by the LEDs, a logo, in particular of the manufacturer of the surface light, are shown, wherein the control unit may be configured to calculate from a logo, the corresponding control information for displaying the logo by the LEDs. In addition, the means for altering may be controlled by the control unit so as to be in the display mode immediately after turning on the panel light for a predetermined time and then to switch to the normal mode.

Thus, when turning on the surface light there is the possibility that for a certain period the manufacturer's logo is visible, whereby a clear assignment of the lamp to a manufacturer by a user is enabled and at the same time after the appropriate time and switching to normal mode, in which LEDs are then operated in the conventional sense in the area light, a normal use as a classic LED surface light is possible.

Likewise, the means for altering could also be controlled by the control unit so that they are in the normal mode in the switched-on state of the surface light and change to the display mode at the beginning of the turn-off, wherein the deactivation of the surface light for a predetermined time is delayed.

Alternatively, it can also be provided that the means for altering are controlled by the control unit such that they are in the switched-on state of the areal light in the normal mode and in the off state in the display mode, the areal light then having an auxiliary supply, which in the off state to supply the LEDs is provided.

Advantageously, in the display mode, a dynamic change of the currents flowing through the LEDs can also take place. In addition, the control unit can also have an interface through which the control unit new control information or new logos can be transmitted. In addition, the LEDs can also be assigned optical means.

Through the interface then there is the possibility that a user of the surface light can make a change in the logo shown, in which case either directly corresponding control information is transmitted via the interface to the control unit, which has been determined, for example, to a computer by a corresponding software from a logo are, or the control unit is transmitted a logo via the interface, in which case the control unit itself from the logo calculates or determines the corresponding control information for displaying the logo.

In addition, it may be provided that at least some of the LEDs are white LEDs or are LEDs of different colors.

Figur 1

Anordnung und Verschaltung der LEDs bei einer aus dem Stand der Technik bekannten Flächenleuchte;

Figur 2

Schaltungsanordnung einer Ausführungsform der Mittel zur Veränderung;

Figur 3

Anordnung und Verschaltung der LEDs bei einer erfindungsgemäßen Flächenleuchte mit den in Figur 2 gezeigten Mitteln zur Veränderung;

Figur 4

erfindungsgemäße Flächenleuchte mit der in Figur 3 gezeigten Anordnung und Verschaltung der LEDs mit einer Steuereinheit.

The invention will be explained in more detail with reference to embodiments and the accompanying drawings. Show it:

FIG. 1

Arrangement and interconnection of the LEDs in a known from the prior art surface light;

FIG. 2

Circuit arrangement of an embodiment of the means for modification;

FIG. 3

Arrangement and interconnection of the LEDs in a surface light according to the invention with the in FIG. 2 means of change shown;

FIG. 4

Inventive surface light with the in FIG. 3 shown arrangement and interconnection of the LEDs with a control unit.

FIG. 1 shows, as already explained, the arrangement or interconnection of the LEDs 1 in a known from the prior art surface light. The arranged on an LED module LEDs 1 are in this case arranged in several LED strands, the LEDs 1 are connected in series in each LED strand or series. In contrast, the LED strings themselves are then connected in parallel with each other and connected to a constant current source 4. Thus, the LEDs 1 become the most all have the same characteristics and are therefore of the same type, all operated in the same way and accordingly light up in all about the same light. It should be noted that according to the in FIG. 1 circuit shown it is only possible, all LEDs 1 on or off, which means there is no way individual LEDs or groups of LEDs 1 separately in the brightness to regulate or turn off. Accordingly, there is no way in such area lights, a manufacturer logo or a simple picture, for example, when starting the surface light to represent accordingly.

In order to enable the representation of corresponding logos or images in such surface lights while maintaining the basic structure of the series and parallel circuit, the invention provides that at least a portion of the LEDs 1 are assigned means that change the currents flowing through the LEDs 1 allow this, for example, by bridging individual LEDs 1 can happen.

FIG. 2 shows a corresponding circuit arrangement, in which a resistor 2 is arranged parallel to an LED 1. In addition, a switch 3 is provided, with the help of which it can then be selected whether the current provided by the constant current source 4 flows either through the LED 1 or through the resistor 2. In the event that the current flows through the resistor 2, then the current through the LED 1 has been reduced to zero and thus changed. By the in FIG. 2 shown circuit arrangement, it is thus possible to turn on or off individual LEDs 1 independently of the other LEDs 1.

Regarding the dimensioning of the resistors, it should be noted that, for example, a 1/4-watt LED could use a 1/4-watt resistor.

Instead of in FIG. 2 shown resistor 2, it would also be possible, for example, to use a linear regulator.

In FIG. 3 is then shown by way of example an arrangement or interconnection of LEDs, which is provided in a corresponding inventive surface light. The LEDs 1 are in this case arranged on one or more LED modules, wherein in FIG. 3 only one LED module is shown. As with the in FIG. 1 shown arrangement are also in the in FIG. 3 In the arrangement shown, the LEDs are arranged serially in corresponding LED strands, the LED strands being connected in parallel to the constant current source 4. In the case of several LED modules, it may be provided that each LED module has its own constant current source 4 or that a constant current source 4 is provided in common for all LED modules.

In addition, however, it is also provided that each LED 1, a resistor 2 and a switch 3 according to the in FIG. 2 associated circuit arrangement is assigned. Accordingly, it is now possible that each LED 1 of in FIG. 3 shown individually bridged and thus can be switched on and off. At the same time, however, is ensured in the event that, for example, only the first LED 1 in the first strand or bridged, ensured by the resistor 2 that still the current of Kontantstromquelle 4 is approximately evenly distributed to the LED strands and thus no danger to the other, still connected, LEDs 1 exists.

Compared to media lights, in which each LED itself is individually connected and controlled, is accordingly provided in the surface light according to the invention, as before, that the LEDs are still arranged in a series and / or parallel connection. Nevertheless, the means for changing the possibility to change the currents flowing through the LEDs, for example, by bridging the LEDs to reduce the current to zero. By this configuration, it is now possible that the logo of a manufacturer or a simple picture, for example, when turning on the surface light, are displayed, whereby a customer gets the opportunity to move the brand of its surface light by presenting a manufacturer's logo in the focus.

It would also be conceivable here, however, that other customer information, which can be displayed relatively simply by LEDs, can be displayed.

For controlling the means for changing the currents flowing through the LEDs, the surface light according to the invention has a control unit. In FIG. 4 a surface lamp is shown which includes a corresponding control unit 5. At the in FIG. 4 shown surface light according to the invention are the LEDs 1 according to the in FIG. 3 arranged arrangement or interconnected. It is provided that the control unit 5 in each case has a connection to the switches 3 and thereby can control or change the switching state of each switch 3. The control unit 5 is therefore designed to control the switches 3 in such a way that they already exist between the two FIG. 2 change explained switching states. This is, on the one hand, a switching state in which the current flows through the LEDs 1 and, on the other hand, a switching state in which the current flows through the resistors 2.

The power supply of the control unit can either be done via an additional power source or via the same power source that supplies the LEDs.

For controlling the switches 3, the control unit 5 has corresponding control information which is stored in the control unit 5. This control information results here from a logo or simple image, which can be determined based on the given logo or image, which LEDs 1 should light and which not. According to this information is then recorded in the control information which switching state each switch 3 should take.

The determination or calculation of the control information from a logo or a simple image can take place here directly in the control unit 5. Alternatively, it would also be conceivable that software is provided on an external device, for example a PC, which performs the corresponding task and determines or calculates corresponding control information. In both cases, the control unit 5 can additionally have an interface 6, by which the control unit 5 either corresponding control information or logos or images are transmitted.

It should be noted here that corresponding control information can already be stored in the control unit 5 during the production of the surface light. At a later time then, for example, by a customer, new or additional control information or logos or images are stored in the control unit 5 via the interface 6, whereby a subsequent change of the logo or image shown is possible. The interface 6 may be, for example, a direct attachment possibility for a PC or a similar device. Alternatively, the interface 6 could also be intended to be connected to a corresponding bus.

At the in FIG. 4 shown surface light, it makes sense that each LED 1, a resistor 2 and a switch 3 is assigned, since by the interface 6, a change of the logo or image and thus the control information, which are stored in the control unit 5, is possible. In the event, however, that with the surface light always the same logo or picture to be displayed, a corresponding interface 6 is no longer necessary. Accordingly, the same control information is then always stored in the control unit 5, which is why it would then no longer be necessary for each LED 1 to be assigned corresponding resistors 2 and switches 3. In this case, it would only be necessary that only the LEDs 1 resistors 2 and switch 3 are assigned, which must be turned off for the representation of the logo or image.

When using the surface light is then provided that the control unit 5 is adapted to control the switches 3 so that they are either in a normal mode or in a display mode, wherein in the normal mode, none of the LEDs 1 is bridged, i. that the switches 3 are all in the switching state in which the current flows via the LEDs 1 and not via the resistors 2. On the other hand, in the display mode, it is provided that according to the control information, the switches 3 are either in the switching state in which the current flows through the LEDs 1 or in the switching state in which the current flows through the resistors 2, i. that according to the logo to be displayed a part of the LEDs 1 is bridged by the resistors 2 by means of the switch 3.

In normal mode, there is thus no difference to the surface lights already known from the prior art. In contrast, it is then possible in the display mode that a corresponding logo or an image can be displayed. It is conceivable, for example, that directly after switching on the surface light for a predetermined short time the presentation mode is selected and then after the predetermined time in the normal mode is changed. As a result, then there is the possibility that when you turn on the surface light briefly the manufacturer's logo is displayed, then the surface light, however, then again behaves just like a well-known from the prior art surface light.

It would also be possible that a logo or an image when switching off the surface light to be displayed. For this purpose, it may be provided that the normal mode is selected in the switched-on state and is then switched to the display mode at the beginning of the switch-off process, wherein the complete deactivation of the surface light is delayed in this case for a predetermined time.

Alternatively, it could also be provided that the display mode is selected in the switched-on state of the areal light and in the switched-off state, whereby the areal light in the switched-on state again behaves like a surface light already known from the prior art. In the off state, in which the surface light has not been used at all, but then it is possible to display, for example, a corresponding manufacturer logo. It should be noted, however, that the supply of the surface light in the off state is not given, which is why the surface light then has an auxiliary supply, which is provided in the off state to supply the LEDs.

In addition, it can also be provided that a dynamic change of the currents flowing through the LEDs occurs during the display mode. For example, in the case of FIG. 3 shown arrangement during the display mode, a change in the switching states of some of the switches 3 are made, whereby a dynamic change of the logo is possible. In general, however, it can also be provided that the means for altering change the currents flowing through the LEDs, thereby enabling a dynamic change in the brightness of the LEDs during the display mode.

Furthermore, it can still be provided that the arrangement of the LEDs, which are provided for the representation of the logo or used, does not have to correspond to the later appearance of the logo. For this purpose, the surface light then has additional optical elements, which are arranged in front of the LEDs and influence the light output of the LEDs accordingly. In this case, however, it should be noted that a change in the representation of the emitted light is effected by the optical elements, whereby possibly also a change of the control information is necessary in order to be able to display the corresponding logo as desired. In this case, it is then provided that the control unit 5 or the external device takes into account the optical elements when determining or calculating the control information from a logo or a simple image. In the case of media luminaires, however, such optical elements are not provided since the visible light point generated there always directly corresponds to the underlying LED.

To calculate or determine the control information from a logo or image, for example, algorithms can be used, which are similarly used in matrix printers application.

The surface light of the invention has mostly white LEDs. It is also conceivable, however, that different colored LEDs can be used.

Furthermore, it would also be conceivable that it is not necessary for the representation of a logo that the LEDs must be individually regulated or switched off, but rather that a group of LEDs, for example a part of an LED string or an entire LED string, should be switched off or bridged. In that case, it would then not be necessary for each LED to have corresponding means for changing the currents flowing through the LEDs. Rather, it could then be provided that, for example, a complete LED string corresponding means are assigned to change.

Overall, it should also be noted that the means of change in addition to bridging the LEDs can also allow dimming of the LEDs. Here, however, depending on the interconnection of the LEDs would be one or more Normalizing resistors in the parallel LED strings are required to prevent different amounts of current from flowing through the LEDs.

Claims (19)

Surface light, with at least one LED module, on which at least two LEDs (1) are arranged in a 1- or 2-dimensional series and / or parallel connection,
characterized,
in that at least part of the LEDs (1) arranged on the LED module are assigned means (2, 3) which allow a change in the currents flowing through the LEDs (1). A surface light according to claim 1,
characterized,
in that a respective LED (1) is assigned means for changing (2, 3). A surface light according to claim 2,
characterized,
that each LED (1) is associated with means for variation (2, 3). A surface light according to one of the preceding claims,
characterized,
in that the means for changing (2, 3) make it possible to dim the LEDs (1). A surface light according to one of the preceding claims,
characterized,
in that the means for changing (2, 3) enable the LEDs (1) to be bridged over. A surface light according to one of the preceding claims,
characterized,
in that a constant current source (4) for supplying the LEDs (1) with current is provided. A surface light according to claim 5 and 6,
characterized,
in that the means for altering have a switch (3) and a resistor (2) arranged parallel to one LED (1) or a plurality of LEDs (1), wherein the switch (3) is arranged and configured in such a way that, depending on the switching state the constant current source (4) provided current either through the LED (1) or LEDs (1) or through the resistor (2) flows. A surface light according to one of the preceding claims,
characterized,
in that the LED module has a control unit (5) for controlling the means for changing (2, 3). A surface light according to claim 7,
characterized,
that control information is stored in the control unit (5) and in that the control unit (5) is designed to control the means (2, 3) for changing (2, 3) so that they are either in a normal mode or in a display mode, in normal mode the currents flowing through the LEDs (1) are not substantially changed by the means (2, 3) for variation (2, 3), and in the display mode a change in the currents flowing through the LEDs (1) is made in accordance with the control information. A surface light according to claim 8,
characterized,
that in the display mode by the LEDs (1) a logo, in particular the manufacturer of the surface light, or an image is displayed. A surface light according to claim 9,
characterized,
in that the control unit (5) is designed to calculate from a logo or image the corresponding control information for displaying the logo or image by the LEDs (1). A surface light according to any one of claims 8-10,
characterized,
that the means for modifying (2, 3) in such a manner by the control unit (5) are controlled such that they are located directly after switching on the lamp surface for a predetermined time in the display mode and then switch to the normal mode. A surface light according to any one of claims 8-11,
characterized,
that the means for modifying (2, 3) in such a manner by the control unit (5) are controlled such that they are in the turned-on state of the area light in the normal mode and switch to the beginning of the turn-off operation in the display mode, wherein the switching off of the surface of light for a predetermined time is delayed. A surface light according to any one of claims 8-10,
characterized,
in that the means for changing (2, 3) are controlled by the control unit (5) in normal mode when the surface-mounted light is switched on and in display mode when switched-off, the surface light having an auxiliary supply that, when switched off, is for Supply of LEDs is provided. A surface light according to any one of claims 8-13,
characterized,
that in the display mode, a dynamic change of the currents flowing through the LEDs (1) takes place. A surface light according to any one of claims 8-14,
characterized,
in that the control unit (5) has an interface (6) by means of which new control information or new logos or images can be transmitted to the control unit (5). A surface light according to one of the preceding claims,
characterized,
in that the LEDs (1) are assigned optical elements. A surface light according to one of the preceding claims,
characterized,
that it is at least at a part of the LEDs (1) are white LEDs. A surface light according to one of the preceding claims,
characterized,
that it is at least at a part of the LEDs (1) to differently colored LEDs.

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