DE102017111087A1 - Method for optical function monitoring of the light emission of at least three LED lamps in luminaires - Google Patents

Abstract

A method is proposed which utilizes the photosensitivity of light-emitting diodes as lighting means in the de-energized state for light of light-emitting diodes other than other light-emitting means for the test of these light-emitting diodes. In this case, a light source, that is to say a first LED, of a light-emitting means group is energized from a plurality of LEDs. As a result, it emits light that is received by other light sources, that is to say other LEDs, the light source group or the light fixture, which can comprise a plurality of light source groups, and is converted into a signal that can be evaluated. This makes it possible to recognize a) whether the lighting means, ie the LEDs, are working properly and, if appropriate, which lighting means has an error in the event of a defect. In contrast to the prior art, the rated signal path contains a light path. Thus, in contrast to the prior art, the actual light emission of at least one light source is detected.

Description

preamble

The proposed method is directed to a test for light emission for a first luminous means of a luminaire for illumination or display purposes with two or more light sources, in particular LEDs.

General introduction

The use of light-emitting diodes (LEDs) as illuminants for safety-relevant tasks in vehicles is becoming increasingly important. In particular, vehicles with autonomous or semi-autonomous states require, for example, an LED diagnostic capability in optical status indicators (e.g., LED lightbands). At least the states "LED lights up" or "LED does not light up" should be detected in order to detect failed LEDs. From the prior art, only methods for indirect diagnosis are known, which evaluate the voltage dropping across the LEDs or the current or power consumption of the LEDs. For this purpose, intelligent drivers are used, but the diagnosis in conjunction with a driver is only indirectly via a voltage / current evaluation.

State of the art

For example, from the writings DE 10 2015 008 110 A1 . DE 10 2015 017 086.4 (still unpublished), DE 10 2015 008 109 A1 . DE 10 2015 017 087.2 (still unpublished), EN 10 2016 105 516 B3 . DE 10 2016 1055 17B3 . EN 10 2016 119 584.7 (still unpublished), US2008 0 204 029 A1 . US 2007 0 159 750 A1 . EP 0 955 619 A1 . DE 10 2011 120 781 A1 . DE 11 2009 005 227 T5 . DE 10 2014 107 947 A1 . US 2012 0 200 296 A1 . US 2006 0 170 287 A1 . US 2007 0 159 750 A1 Methods and devices for monitoring the electrical or thermal parameters of light-emitting diodes and light-emitting diode chains are known.

The main disadvantage of the prior art is therefore that the actual function of the light output of the lighting means is not checked.

task

The proposal is therefore based on the object to provide a solution which does not have the above disadvantages of the prior art and has further advantages.

This object is achieved by a method according to claim 1.

Solution of the task

In RGB lighting, several LED Emitters arranged as RGB bulbs in a housing. This combination of several LEDs as lighting means to form an overall device is hereinafter referred to as a light source group comprising a plurality of light sources. Within such a group of bulbs, the light emission of a single LED the group of bulbs of a first color, if they are another LED irradiated the first color of the lamp group, as a photocurrent, or photo voltage on this adjacent, not driven LED the illuminant group can be detected.

The emission of light of this LED the light source group thus generates at the neighboring LED the lighting group a photocurrent, which in turn to a LED Voltage at the irradiated LED the lighting group leads. These LED Voltage is called photo voltage below. The product of photocurrent and photo voltage corresponds to that in the irradiated LED converted into electrical energy light energy. This energy is preferably measured at a external impressed voltage of 0V as a pure photocurrent or at an externally impressed current of 0A as a pure photo voltage. The skilled person can also determine the energy generated in other operating points, this determination is then more expensive. Photoelectric current and photo voltage can be used as measures of the irradiated LED Light output can be used.

Since in automotive applications the control processors which drive the light source groups are equipped with an analog-to-digital converter in order to be able to detect various parameters of the lighting device, these analog-to-digital converters of the control processors can be used, for example, via a multiplexer to the photo voltage or the photocurrent or, more generally, by the irradiation in the irradiated LED to measure the energy generated by the lamp group and to determine a measured value. As is known, what intensity of the radiating LED should be sent out, the thus determined measured value can be compared with a threshold value. Preferably, the radiated intensity is distinguished only between on and off. If the measured value is below the threshold, then either the radiating one transmits LED too little light output or the irradiated LED generates too little photo voltage or photocurrent. In this respect, it can already be assumed that the lighting means group as such has at least one of these defects.

A group of bulbs within the meaning of this furnace is usually more than one LED include. Typically, but not necessarily, a group of bulbs for use in the proposed method includes red, green and blue LED or similar combinations of complementary colors. In that case, by cyclically interchanging the radiating and the irradiated LEDs of such a group of bulbs in a single error can be found which LED is actually flawed. Thus, a direct diagnosis of LED -Light emission possible with LED light sources. In contrast, in the prior art, only the location of the electrical operating parameters is evaluated within predetermined tolerance ranges. Whether the lamps actually emit light is not checked. The proposed method thus allows a direct examination of the light emission instead of an indirect conclusion to such a light emission. Different groups of lamps of a larger lighting device can also radiate among each other. Therefore, the method proposed here is also suitable for testing light bands with suitable bulbs, which are arranged along the light strip. Preferably, the bulbs on the luminous band are then objected to the same. In the case of the same illuminants, the same optical couplings between the individual luminous means should then occur in the case of linear, planar laying, which thus allows the application of the proposed method for this case. If the luminous means are not equally spaced along such a luminous band, the application of the proposed method presupposes a previously known distance or a previously known optical coupling between the luminous means. This precognition can be determined by design on a prototype in the form of suitable coupling parameters. In the case of identical light bands, similar coupling factors can be expected with certain tolerances. A suitable foreknowledge can also be obtained to some extent by simulation or calculation of the mutual irradiation intensity. If the luminous band is not to be laid planar, this has the same effect as different spacings of the illuminants of the luminous band. The proposed method is also suitable for testing luminous mats, that is to say two-dimensional arrangements of luminous means. In this case, the lighting means are preferably arranged in the form of a two-dimensional grid. Particularly preferred is a cubic or hexagonal arrangement of the lamps to each other. In case of deviations from such regular structures, a prior knowledge can be obtained by simulation or experiments with prototypes, which provide the necessary parameters for the calculation of the optical coupling.

An objection typically raised by experts is that the light-emitting means groups generally have differently colored LEDs in order to be able to represent all human-recognizable colors in the color space as RGB-color. Therefore, it should be safe in this opinion, with a short-wave LED , so for example a blue one LED , in a longer wavelength LED So, for example, a red LED to cause a photocurrent, since the band gap of the long-wave LED So, for example, the red LED , smaller than the photon energy of the shortwave LED So the blue one LED , radiated photons. Conversely, according to this expert opinion, it is expected by experts that it would not be safe to do so, with a longer-term one LED So, for example, a red LED , in a shorter wavelength LED , so for example a blue one LED to cause a certainly measurable photocurrent or a sure measurable photo voltage, since the band gap of the shortwave LED So, for example, the blue LED , greater than the photon energy of the longwave LED So, for example, the red LED , emitted photons is.

However, this circumstance does not stand in the way of a diagnosis since it is possible to detect the condition sufficiently by means of reciprocal combinatorics.

Experiments have shown that a defect in the emission does not produce a measurable effect (photocurrent / voltage) during absorption. This can be derived theoretically from Einstein's law that the emission coefficient is always equal to the absorption coefficient.

• - Schritt 1: Die blaue LED soll blaues Licht abstrahlen. Die rote LED und die grüne LED werden bevorzugt nicht bestromt.
• - Schritt 2: Es wird ein erster Messwert für die Fotospannung und/oder den Fotostrom der roten LED ermittelt. Ggf. kann beispielsweise über das Produkt aus Fotospannung und Fotostrom die Fotoleistung der roten LED ermittelt werden.
• - Schritt 3: Es wird ein zweiter Messwert für die Fotospannung und/oder den Fotostrom der grünen LED ermittelt. Ggf. kann beispielsweise über das Produkt aus Fotospannung und Fotostrom die Fotoleistung der grünen LED ermittelt werden.
• - Schritt 4: Der erste Messwert wird mit einem Schwellwert für den ersten Messwert bei Bestrahlung der roten LED durch die blauen LED verglichen und ein erster Vergleichswert ermittelt.
• - Schritt 5: Der zweite Messwert wird mit einem Schwellwert für den zweiten Messwert bei Bestrahlung der grünen LED durch die blauen LED verglichen und ein zweiter Vergleichswert ermittelt.
• - Der erste Vergleichswert nimmt dabei einen ersten Zustand an, wenn der erste Messwert unterhalb des Schwellwerts für den ersten Messwert bei Bestrahlung der roten LED durch die blauen LED liegt, und einen zweiten Zustand an, wenn der erste Messwert oberhalb des Schwellwerts für den ersten Messwert bei Bestrahlung der roten LED durch die blauen LED liegt. Der erste Zustand entspricht also dem Fall, dass die blaue LED strahlt und die rote LED das Licht der blauen LED empfängt und in einen Fotostrom bzw. eine Fotospannung umwandelt. Der zweite Zustand entspricht dann dem Fall, dass zumindest einer dieser beiden Vorgänge nicht stattfindet.
• - Der zweite Vergleichswert nimmt dabei einen ersten Zustand an, wenn der zweite Messwert unterhalb des Schwellwerts für den zweiten Messwert bei Bestrahlung der grünen LED durch die blauen LED liegt, und einen zweiten Zustand an, wenn der zweite Messwert oberhalb des Schwellwerts für den zweiten Messwert bei Bestrahlung der grünen LED durch die blauen LED liegt. Der erste Zustand entspricht also dem Fall, dass die blaue LED strahlt und die grüne LED das Licht der blauen LED empfängt und in einen Fotostrom bzw. eine Fotospannung umwandelt. Der zweite Zustand entspricht dann dem Fall, dass zumindest einer dieser beiden Vorgänge nicht stattfindet.
• - Schritt 6: Es folgt das Ermitteln des Zustands der LEDs aus dem ermittelten ersten Vergleichswert und dem ermittelten zweiten Vergleichswert.
• - Ist der erste Vergleichswert im zweiten Zustand und der zweite Vergleichswert im zweiten Zustand, so strahlt die blaue LED und das Licht der blauen LED wird von der roten LED empfangen und von der grünen LED empfangen. Dies lässt darauf schließen, dass die blaue LED korrekt arbeitet und dass die grüne LED korrekt arbeitet und dass die rote LED korrekt arbeitet.
• - Ist der erste Vergleichswert im zweiten Zustand und der zweite Vergleichswert im ersten Zustand, so strahlt die blaue LED und das Licht der blauen LED wird von der roten LED empfangen und von der grünen LED nicht empfangen. Dies lässt darauf schließen, dass die blaue LED korrekt arbeitet und dass die grüne LED nicht korrekt arbeitet und dass die rote LED korrekt arbeitet.
• - Ist der erste Vergleichswert im ersten Zustand und der zweite Vergleichswert im zweiten Zustand, so strahlt die blaue LED und das Licht der blauen LED wird von der roten LED nicht empfangen und von der grünen LED empfangen. Dies lässt darauf schließen, dass die blaue LED korrekt arbeitet und dass die grüne LED korrekt arbeitet und dass die rote LED nicht korrekt arbeitet.
• - Ist der erste Vergleichswert im ersten Zustand und der zweite Vergleichswert im ersten Zustand, so strahlt die blaue LED wahrscheinlich nicht und das Licht der blauen LED wird von der roten LED nicht empfangen und von der grünen LED nicht empfangen. Dies lässt darauf schließen, dass entweder als erste Möglichkeit die blaue LED nicht korrekt arbeitet oder dass als zweite Möglichkeit die grüne LED und die rote LED nicht korrekt arbeiten.

The procedure for measuring RGB bulbs with a blue one LED , which is intended to emit blue light, and a green one LED , which is intended to emit green light, and a red one LED , which is intended to emit red light, can now look like this:

• - Step 1: The blue one LED should emit blue light. The Red LED and the green one LED are preferably not energized.
• - Step 2: It will be a first reading for the photo voltage and / or the photocurrent of the red LED determined. Possibly. For example, using the product of photo voltage and photocurrent, the photo performance of the red LED be determined.
• - Step 3: It will be a second reading for the photo voltage and / or the photocurrent of the green LED determined. Possibly. For example, using the product of photo voltage and photocurrent, the photo power of the green LED be determined.
• Step 4: The first measured value is added with a threshold value for the first measured value Irradiation of the red LED through the blue ones LED compared and a first comparison value determined.
• Step 5: The second reading is taken with a threshold for the second reading when the green is irradiated LED through the blue ones LED compared and a second comparison value determined.
• - The first comparison value assumes a first state, when the first measured value below the threshold value for the first measured value when irradiating the red LED through the blue ones LED and a second state if the first measured value is above the threshold value for the first measured value when the red light is irradiated LED through the blue ones LED lies. The first state corresponds to the case that the blue one LED shines and the red LED the light of the blue LED receives and converts into a photocurrent or a photo voltage. The second state then corresponds to the case that at least one of these two processes does not take place.
• - The second comparison value assumes a first state when the second measured value below the threshold value for the second measured value when irradiating the green LED through the blue ones LED and a second state if the second measured value is above the threshold value for the second measured value when the green is irradiated LED through the blue ones LED lies. The first state corresponds to the case that the blue one LED shines and the green LED the light of the blue LED receives and converts into a photocurrent or a photo voltage. The second state then corresponds to the case that at least one of these two processes does not take place.
• - Step 6: It follows the determination of the state of the LEDs from the determined first comparison value and the determined second comparison value.
• If the first comparison value is in the second state and the second comparison value is in the second state, then the blue one radiates LED and the light of the blue LED is from the red LED received and from the green LED receive. This suggests that the blue LED works correctly and that the green LED works correctly and that the red LED works correctly.
• If the first comparison value is in the second state and the second comparison value is in the first state, then the blue one radiates LED and the light of the blue LED is from the red LED received and from the green LED not received. This suggests that the blue LED works correctly and that the green LED does not work correctly and that the red LED works correctly.
• If the first comparison value is in the first state and the second comparison value is in the second state, then the blue one radiates LED and the light of the blue LED is from the red LED not received and from the green LED receive. This suggests that the blue LED works correctly and that the green LED works correctly and that the red LED not working correctly.
• If the first comparison value is in the first state and the second comparison value is in the first state, then the blue one radiates LED probably not and the light of the blue LED is from the red LED not received and from the green LED not received. This suggests that either the first option is the blue one LED does not work correctly or that the second option is the green one LED and the red one LED not working properly.

This measurement can be with the green LED as transmitter and the red one LED as the only receptions are also performed in an analogous manner to obtain more information. Of course, more colors and / or LEDs are usable.

On the other hand, a clear diagnosis with assignment of the exact error to a specific light source (here LEDs) is often not required in real applications. As a rule, a statement about a defect of the lighting group is sufficient in itself.

1. a) Innerhalb einer Leuchtmittelgruppe durch Absorption zwischen benachbarten LEDs dieser Leuchtmittelgruppe oder
2. b) Leuchtmittelgruppen übergreifend, wobei die Lichtemission einer LED einer ersten Leuchtmittelgruppe mittels einer LED einer benachbarten Leuchtmittelgruppe detektiert werden kann.

It is now proposed that the light detection for diagnosis can take place as follows:

1. a) Within a group of lamps by absorption between adjacent LEDs of this group of lamps or
2. b) illuminant groups across, the light emission of a LED a first group of bulbs by means of a LED an adjacent group of bulbs can be detected.

For example, the method b) within a LED Chain along a LED Band can be used. Since the distances are then larger, but then the signals are smaller. In this case, a diagnosis of all LEDs of all groups of lamps within a diagnostic cycle or by meaningful coding of the control, if necessary, also possible during operation.

It is therefore proposed, the photocurrent of a LED at such times when it is not controlled, ie in an State is and thus does not emit light itself. Furthermore, there must be at least one other at this time LED in on state, so radiate light. This light must be in sufficient quantity on the LED fall in the off state and be suitable for its level, in the LED in the off state so that a measurable photocurrent or a measurable photo voltage results. But then only the can be evaluated LED in the off state, since several LEDs in the LED could radiate in the off state.

It is therefore also proposed to measure the photocurrent of several LEDs in parallel or quasi-parallel time to such times in which they are not driven and thus are in an off state and thus emit no light itself. Furthermore, at this time has another LED in on state, so radiate light. This light must drop enough on the LEDs in the off state and its level be suitable for radiating into the LEDs in the off state so that each results in a measurable photocurrent. The rating is then preferably the LED in on state.

The proposed method thus serves to carry out a test for light emission for a first light source, preferably for a first light source LED , a luminaire intended for lighting or display purposes. The luminaire has at least one first light source - the first said LED - And at least one further second illuminant - a second LED , The first light source - the first LED and the second bulb - the second LED - Each can assume an on state in which they emit light with a light source specific first light output, and each assume an off state in which they emit light with a light source specific second light output. This means that a first light output can be assigned to the first luminous means and a first light output can be assigned to the second luminous means and that the first light output of the first luminous means can be different from the first light output of the second luminous means. This also means that a second light output can be assigned to the first light source and a second light output can be assigned to the second light source and that the second light output of the first light source can be different from the second light output of the second light source. In the following of this disclosure cases with more than two bulbs are considered, where then the analog applies. The amount of the first light output is greater than the amount of the second light output. Preferably, the second light output is zero or nearly zero, which means that in the off state, the relevant light source preferably does not light up. The first light source, so preferably the first LED , is turned on in the proposed method and thus brought into the on state. The second light source is brought into the off state, that is switched off. Preferably, the first lighting means, so preferably the first LED , so to the second light source, so preferably the second LED , arranged that the first illuminant then irradiates the second illuminant with its light. By means of said analog-to-digital converter then takes place the measurement of an electrical parameter of the second light source, that is preferably the second LED , to determine a measured value for this parameter. In case of a second LED As a second light source, this electrical parameter is preferably a photo voltage of the second LED which generates them as a result of the irradiation, or a photocurrent of the second one LED It generates as a result of irradiation. It is therefore important that the value of the selected parameter depends on the illumination in the form of the light power radiated into the second illuminant and that the second illuminant is brought into a state in which this dependency can be measured. Therefore, the second is particularly preferred LED switched off to achieve a good signal-to-noise ratio. The measured value thus detected-typically by the said analog-to-digital converter-is then compared with a threshold value. This is usually done by the program of the control computer or a computer to which the control computer sends the measured value or a value derived therefrom. This evaluates the first and / or second luminous means or the luminaire as "possibly defective" if the comparison of the measured value with the threshold value reveals that the first light output of the first luminous means is too low or the value of the parameter of the second luminous means is insufficient , In the case of two LEDs, this means that the comparison of the measured value with the threshold results in that the photo voltage or the photocurrent, the second LED generated, is too low. This too low photocurrent or this too low photo voltage is then either on a too low first light output of the first light source, ie the first LED , and thus to a low irradiation of light power in the second light source, so the second LED , due or on a too low sensitivity of the second light source, so the second LED opposite to the irradiation by the first light source, that is by the first LED , Also in this last case can typically be a defect of the second LED be assumed. In order to make the necessary distinction, the process can be extended to three bulbs. Since there are three bulbs of different colors in most bulbs, this enhancement can typically be applied to bulbs with adjustable color. It is then used to test a first light source first test carried out according to the method described above with the first and second lighting means and a second test with the first and third lighting means. In this case, the third light-emitting means is likewise switched off and measured, that is to say how the second light-emitting means is treated in accordance with the method described above. This results in a first test result for the first test and a second test result for the second test. These two test results can each have the values "in order" or "possible defect" of one of the two illuminants involved in the respective test. The first test result can thus be the values "in order" or "possible defect" for the first lighting means, that is, for example, the first LED , and for the second light source, so for example the second LED , to have. The second test result can thus be the values "in order" or "possible defect" for the first lighting means, that is, for example, the first LED , and for the third light source, so for example the third LED , to have.

If both tests are "OK", the first light source is ok.

If the first test is "OK" and the second test is "Possible defect", then there is probably a defect of the third light source, in the case of LEDs of the third one LED , in front.

If the first test "possible defect" and the second test "OK", then there is probably a defect of the second light source, so in the case of LEDs of the second LED , in front.

If the first test "possible defect" and the second test "possible defect", then there is a defect of the first light source, so in the case of LEDs of the first LED , in front.

Preferably, these tests do not run sequentially in succession, but more or less in parallel. For better clarity, we now assume that the third light source is turned on and the first and second light sources are used as a sensor for the light of the third light source. This is a renaming to improve the clarity of the description over the immediately preceding description. In the description above, the first bulb was tested. By pure renaming the third illuminant will now be tested. This does not change the technical content. The method then provides that the third light source, ie the third LED , is turned on and thus brought into the ON state, while the first and second lighting means, so preferably the first and second LED , switched off, so be brought into the off state. The arrangement of the first, second and third lighting means to one another should now be such that the third lighting means can irradiate the first and second lighting means. In addition, such irradiation should produce a measurable effect in the first and second bulbs. In the case of LEDs, this is the generation of a photocurrent or a photo voltage in the first and second LED , Is the third lamp, so preferably the third preferred LED , in the on-state, it then irradiates the first and second bulbs, so the first and second LED , and there causes the said effect, which in the case of LEDs, the generation of said photospannung and said photocurrent in the first and second LED means. In order to be able to detect the generated effect in the first and second luminous means, a first parameter of the first luminous means in the form of a first measured value and a second parameter of the second luminous means in the form of a second measured value are now preferably by means of the analog-to-digital converter of the control processor detected, which are modified by the irradiation with the light of the first light source. In the case of LEDs, the first parameter is the first measured value of a first photo voltage or of a first photocurrent, which is defined by the first LED upon irradiation with light of the third LED and the second parameter is the second measured value of a second photo voltage or of a second photocurrent, which is generated by the second LED upon irradiation with light of the third LED be generated.

The first measured value is preferably compared by the control processor with a first threshold value. The second measured value is preferably compared by the control processor with a second threshold value.

The control processor preferably rates the third lighting means as defective if the comparison of the first measured value with the first threshold value and the second measured value with the second threshold value reveals that the first light output of the third lighting means is too low.

In the case of a first LED The first light source is the photocurrent or the photo voltage of the first LED preferably for measuring a first illumination value by the analog-to-digital converter of the control processor.

In case of a second LED as a second light source of the photocurrent or the photo voltage of the second LED preferably for measuring a second illumination value by the analog-to-digital converter of the control processor.

The third LED illuminated in this example again the first LED and the second LED , the both are in the off state during the measurement.

This is followed by the comparison of the first illumination value with a first threshold value and the comparison of the second illumination value with a second threshold value. This comparison is preferably carried out again with the aid of the control processor or a computer to which the control processor has transmitted the first and second illumination values or values derived therefrom.

This evaluates the third LED that the first and second LED Illuminates as defective if the amount of the first illumination value is smaller than the first threshold value and if the amount of the second illumination value is smaller than the second threshold value.

This evaluates the second LED that by the third LED is illuminated as being defective if the magnitude of the first illumination value is greater than the first threshold value and if the magnitude of the second illumination value is less than the second threshold value.

This evaluates the first LED that by the third LED is illuminated as being defective if the magnitude of the first illumination value is less than the first threshold value and if the magnitude of the second illumination value is greater than the second threshold value.

This evaluates the third LED that the first and second LED illuminated as likely to be error-free if the magnitude of the first illumination value is greater than the first threshold value and if the magnitude of the second illumination value is greater than the second threshold value.

Not all of these ratings must always be executed. However, it is suggested that all of these evaluations be made preferable.

Especially suitable are the proposed methods for testing so-called RGB light modules. Such RGB light modules are preferably combinations of three LEDs of different colors. Preferably has a first LED a blue color, a second one LED a green color and a third LED a red color. It is known that it is common in biodynamic light to use a fourth color, which can not be consciously detected by the human eye with the same intensity, which controls the release of melatonin in the human body and thus influences the sleep / wake rhythm. In this respect, more than three colors or focal wavelengths are conceivable. Furthermore, the combination with infrared LEDs as a transmitter for communicative purposes is conceivable. It is therefore also lighting modules with more than four LED Center of gravity wavelengths conceivable.

The 1 schematically shows such an example LED Module with a first LED LED1 and a second LED LED2 and a third LED LED3 ,

2 shows by way of example and schematically a device for carrying out the proposed method. The first LED LED1 of LED Module off 1 is from a first power source S1 with a first stream I1 provided. The second LED LED2 of LED Module off 1 is powered by a second power source S2 with a second stream I2 provided. The third LED LED3 of LED Module off 1 is powered by a third power source S3 with a third stream I3 provided. An analog-to-digital converter ( ADC ) can be connected via an analogue multiplexer ( MUX ), which is controlled by a computer system (μC) to the output nodes of the first power source ( S1 ) or the second power source ( S2 ) or the third power source ( S3 ). Typically, this configuration is also used to reduce the voltage drop across the first LED LED1 or the second LED LED2 or the third LED LED3 to monitor and detect failures during operation. The power sources ( S1 . S2 . S3 ) via a control bus or control signal lines (SB) by the computer system ( .mu.C ) controlled. In the case of the current drawn here by way of example ( S1 . S2 . S3 ) are likely to be in real realizations so-called high-side power sources that draw their energy from the positive supply voltage. Such high-side current sources are preferably realized by means of a current mirror, wherein the MOS diode for reference voltage generation and the current source transistor are preferably connected directly to this positive supply voltage. This preferred realization is in the 2 but not shown. Instead, ideal current source symbols are drawn, which are based on the reference potential ( GND ) are more theoretical in nature. The analog-to-digital converter ( ADC ) reports the measured values to the computer system ( .mu.C ). The computer system ( .mu.C ) carries out the proposed procedure.

Particularly preferred is the measurement of the first LED LED1 in that the computer system ( .mu.C ) the first LED LED1 by turning on the first power source S1 with a non-zero electrical first current I1 supply and the second power source S2 and the third power source S3 off. By means of the multiplexer ( MUX ) and the analog-to-digital converter ( ADC ) determines the computer system ( .mu.C ) then prefers the second photo voltage of the second LED LED2 and the third Photo voltage of the third LED LED3 , The second photo voltage of the second LED LED2 is the potential difference wipe the output node of the second power source S2 and the reference potential GND , The third photo voltage of the third LED LED3 is the potential difference wipe the output node of the third power source S3 and the reference potential GND ,

Particularly preferred is the measurement of the second LED LED2 in that the computer system ( .mu.C ) the second LED LED2 by turning on the second power source S2 with a non-zero electrical second current I2 supply and the first power source S1 and the third power source S3 off. By means of the multiplexer ( MUX ) and the analog-to-digital converter ( ADC ) determines the computer system ( .mu.C ) then prefers the first photo voltage of the first LED LED1 the third photo voltage and the third one LED LED3 , The first photo tension of the first LED LED1 is the potential difference wipe the output node of the first power source S1 and the reference potential GND , The third photo voltage of the third LED LED3 is the potential difference wipe the output node of the third power source S3 and the reference potential GND ,

Particularly preferred is the measurement of the third LED LED3 in that the computer system ( .mu.C ) the third LED LED3 by turning on the third power source S3 with a non-zero electrical third current I3 supply and the second power source S2 and the first power source S1 off. By means of the multiplexer ( MUX ) and the analog-to-digital converter ( ADC ) determines the computer system ( .mu.C ) then prefers the second photo voltage of the second LED LED2 the first photo voltage and the first one LED LED1 , The second photo voltage of the second LED LED2 is the potential difference wipe the output node of the second power source S2 and the reference potential GND , The first photo tension of the first LED LED1 is the potential difference wipe the output node of the first power source S1 and the reference potential GND ,

The thus determined first photo voltage and the second photo voltage and the third photo voltage are preferably after each of these two times three measurements, each with an associated threshold by the computer system ( .mu.C ) compared. The associated threshold values are preferably in the program or data memory of the computer system ( .mu.C ) filed. As you can easily see, the redundancy of the measurements can be used to make fewer measurements and save time. If the computer system detects an error, it signals an error, for example via a signaling line or a data bus to a higher-level unit, for example a bus master or a control unit.

Advantage of the proposal

At least in some implementations, such a diagnostic method makes it possible to test light sources if they are measurably influenced by irradiation with light in at least one operating state. The advantages are not limited to this.

In contrast to the currently used diagnoses, which are only indirect indications about the LED Provide current and voltage and thus do not allow a clear conclusion on an actual emission of light, the proposal presented here allows a clear conclusion on an actual emission of light by a light source or a LED ,

LIST OF REFERENCE NUMBERS

ADC

Analog-to-digital converter;

I1

first current of the first current source (S1) for supplying the first LED (LED1) with electrical energy;

I2

second current of the second current source (S2) for supplying the second LED (LED2) with electrical energy .;

I3

third current of the third current source (S3) for supplying the third LED (LED3) with electrical energy;

GND

Reference potential;

LED

light emitting diode or light emitting diode called. The light emitting diodes here are generally for light sources that can generate a photocurrent and / or a photo voltage when irradiated;

LED1

first LED

LED2

second LED;

LED3

third LED;

MUX

Multiplexer;

S1

first current source for supplying the first LED LED1 with the first current (I1). The first current source is controlled via the control bus (SB) by the computer system (μC);

S2

first power source for supplying the second LED LED2 with the second current (I2). The second current source is controlled via the control bus (SB) by the computer system (μC);

S3

first power source for supplying the third LED LED3 with the third current (I3). The third current source is controlled via the control bus (SB) by the computer system (μC);

SL S

signal line for signaling or transmission of the provided data;

glossary

LED

At a LED in the sense of this disclosure is a light emitting diode. Such LEDs may have different centroid wavelengths. If spoken in the claims of LEDs, so are also included such bulbs that allow the application of the proposed method in the same way.

Centroid wavelength

The centroid wavelength results in the sense of this disclosure as the maximum intensity in the wavelength spectrum of the relevant LED or the relevant light source.

List of quoted writings

• DE 10 2015 008 110 A1 .
• DE 10 2015 017 086.4 (still unpublished),
• DE 10 2015 008 109 A1 .
• DE 10 2015 017 087.2 (still unpublished),
• EN 10 2016 105 516 B3 .
• DE 10 2016 1055 17B3 .
• EN 10 2016 119 584.7 (still unpublished),
• US2008 0 204 029 A1 .
• US 2007 0 159 750 A1 .
• EP 0 955 619 A1 .
• DE 10 2011 120 781 A1 .
• DE 11 2009 005 227 T5 .
• DE 10 2014 107 947 A1 .
• US 2012 0 200 296 A1 .
• US 2006 0 170 287 A1 .
• US 2007 0 159 750 A1

QUOTES INCLUDE IN THE DESCRIPTION

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

Cited patent literature

• DE 102015008110 A1 [0003, 0048]
• DE 102015017086 [0003, 0048]
• DE 102015008109 A1 [0003, 0048]
• DE 102015017087 [0003, 0048]
• DE 102016105516 B3 [0003, 0048]
• DE 102016105517 B3 [0003, 0048]
• DE 102016119584 [0003, 0048]
• US 20080204029 A1 [0003, 0048]
• US 20070159750 A1 [0003, 0048]
• EP 0955619 A1 [0003, 0048]
• DE 102011120781 A1 [0003, 0048]
• DE 112009005227 T5 [0003, 0048]
• DE 102014107947 A1 [0003, 0048]
• US 20120200296 A1 [0003, 0048]
• US 20060170287 A1 [0003, 0048]

Claims (6)

Method for carrying out a test for light emission for a first luminous means of a luminaire for illumination or display purposes with the first luminous means and at least one further second luminous means and a further third luminous means, - Wherein the first light source and the second light source and the third light source can each assume an on state in which they each emit light with a light source specific first light output and each can assume an off state, in the light with a light source specific second light output radiate and - Wherein, based on each lamp of these three bulbs for the amount of the first light output of this bulb is greater than the amount of the second light output of this bulb with the steps - bringing the first lamp in its on state; - Bring the second light source in its off state; - Bring the third bulb in its off state; - Irradiating the second light source with the light of the first light source and - irradiating the third illuminant with the light of the first illuminant; Measuring a first electrical parameter of the second luminous means to determine a first measured value for this first parameter; Measuring a second electrical parameter of the third luminous means to determine a second measured value for this second parameter; - Comparison of the first measured value with a first threshold value; - Comparison of the second measured value with a second threshold value; - Evaluation of the first light source as faulty if the comparison of the measured value with the threshold value shows that the first light output of the first light source is too low. A method of performing a light emission test for a third LED of a luminaire for illumination or display purposes with the third LED and at least one further first LED and another second LED, wherein the first LED and the second LED and the third LED each have an on State in which they can emit light with a specific for the respective LED first light output and each can assume an off state, radiate in the light with a specific light for each LED second power and - with respect to each LED of these three LEDs in itself, the amount of the first light output of this LED is greater than the amount of the second light output of this LED, comprising the steps of - bringing the first LED to its off state; - bring the second LED in its off state; - bring the third LED in its on state; - irradiating the first LED with the light of the third LED and - irradiating the second LED with the light of the third LED; - Measuring the photocurrent or the photo voltage of the first LED to determine a first illumination value; - Measuring the photocurrent or the photo voltage of the second LED to determine a second illumination value; - Comparison of the first illumination value with a first threshold value; - Comparison of the second illumination value with a second threshold value; - Evaluation of the third LED as faulty, If the magnitude of the first illumination value is less than the first threshold value and if the magnitude of the second illumination value is less than the second threshold value. A method of performing a light emission test for a third LED of a luminaire for lighting or display purposes with the third LED and at least one further first LED and another second LED, - Wherein the first LED and the second LED and the third LED each can assume an on state in which they emit light with a specific light for each LED first light output and each can assume an off state, in the light with one for the emit respective LED specific second light output and - With respect to each LED of these three LEDs per se, the amount of the first light output of this LED is greater than the amount of the second light output of this LED with the steps - bring the first LED in its off state; - bring the second LED in its off state; - bring the third LED in its on state; - irradiating the first LED with the light of the third LED and - irradiating the second LED with the light of the third LED; - Measuring the photocurrent or the photo voltage of the first LED to determine a first illumination value; - Measuring the photocurrent or the photo voltage of the second LED to determine a second illumination value; - Comparison of the first illumination value with a first threshold value; - Comparison of the second illumination value with a second threshold value; - Evaluation of the second LED as faulty, If the amount of the first illumination value is greater than the first threshold value and If the magnitude of the second illumination value is less than the second threshold value. A method of performing a light emission test for a third LED of a luminaire for lighting or display purposes with the third LED and at least one further first LED and another second LED, - Wherein the first LED and the second LED and the third LED each can assume an on state in which they emit light with a specific light for each LED first light output and each can assume an off state, in the light with one for the emit respective LED specific second light output and - With respect to each LED of these three LEDs per se, the amount of the first light output of this LED is greater than the amount of the second light output of this LED with the steps - bring the first LED in its off state; - bring the second LED in its off state; - bring the third LED in its on state; - irradiating the first LED with the light of the third LED and - irradiating the second LED with the light of the third LED; - Measuring the photocurrent or the photo voltage of the first LED to determine a first illumination value; - Measuring the photocurrent or the photo voltage of the second LED to determine a second illumination value; - Comparison of the first illumination value with a first threshold value; - Comparison of the second illumination value with a second threshold value; - evaluation of the first LED as faulty, • if the magnitude of the first illumination value is less than the first threshold and If the magnitude of the second illumination value is greater than the second threshold value. Method according to the Claims 2 or 3 or 4 characterized in that the first LED has a different centroid wavelength than the second LED, and that the first LED has a different centroid wavelength than the third LED, and that the third LED has a different centroid wavelength than the second LED. Method according to the Claims 2 or 3 or 4 characterized in that - the first LED has a different color than the second LED and - that the first LED has a different color than the third LED and - that the third LED has a different color than the second LED.

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