DE19933735A1 - LED display board with regulation of current to LEDs to provide constant brightness - Google Patents

LED display board with regulation of current to LEDs to provide constant brightness

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Publication number
DE19933735A1
DE19933735A1 DE19933735A DE19933735A DE19933735A1 DE 19933735 A1 DE19933735 A1 DE 19933735A1 DE 19933735 A DE19933735 A DE 19933735A DE 19933735 A DE19933735 A DE 19933735A DE 19933735 A1 DE19933735 A1 DE 19933735A1
Authority
DE
Germany
Prior art keywords
light
temperature
image content
controlled
led
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
DE19933735A
Other languages
German (de)
Inventor
Walter Heitmann
Alexander Boehlendorf
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
LEUROCOM ELECTRONIC DISPLAYS GMBH, 71364 WINNENDEN
Original Assignee
LEUROCOM VISUELLE INFORMATIONS
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by LEUROCOM VISUELLE INFORMATIONS filed Critical LEUROCOM VISUELLE INFORMATIONS
Priority to DE19933735A priority Critical patent/DE19933735A1/en
Publication of DE19933735A1 publication Critical patent/DE19933735A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/04—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of a single character by selection from a plurality of characters, or by composing the character by combination of individual elements, e.g. segments using a combination of such display devices for composing words, rows or the like, in a frame with fixed character positions
    • G09G3/06—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of a single character by selection from a plurality of characters, or by composing the character by combination of individual elements, e.g. segments using a combination of such display devices for composing words, rows or the like, in a frame with fixed character positions using controlled light sources
    • G09G3/12—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of a single character by selection from a plurality of characters, or by composing the character by combination of individual elements, e.g. segments using a combination of such display devices for composing words, rows or the like, in a frame with fixed character positions using controlled light sources using electroluminescent elements
    • G09G3/14—Semiconductor devices, e.g. diodes
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/22—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources
    • G09G3/30—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels
    • G09G3/32—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED]
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
    • H05B45/10—Controlling the intensity of the light
    • H05B45/18—Controlling the intensity of the light using temperature feedback
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2310/00—Command of the display device
    • G09G2310/02—Addressing, scanning or driving the display screen or processing steps related thereto
    • G09G2310/0264—Details of driving circuits
    • G09G2310/0272—Details of drivers for data electrodes, the drivers communicating data to the pixels by means of a current
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/04—Maintaining the quality of display appearance
    • G09G2320/041—Temperature compensation

Abstract

Display board matrix of LEDs has circuitry with temperature dependent resistor (TC) in resistance network with series (RV) and/or parallel resistor (RP) in LED control current path. Temperature dependent resistance network is set to nearly compensate the luminance/temperature characteristic due to heating of LED. When new image is to be shown on display, it is shown together with attenuated previous image. Previous image's attenuation is smaller, the longer the previous image was displayed. Attenuation is adjusted to the thermal time constant of the LEDs. At the same time the new image is attenuated, but attenuation is weaker the longer the new image is shown. The attenuation is constantly adjusted to the current display duration.

Description

Die Erfindung betrifft eine Vorrichtung zur Anzeige von Zeichen und Bildern mit Leuchtdioden gemäß Oberbegriff des Anspruches 1 bzw. 2.The invention relates to a device for displaying characters and images with light emitting diodes according to 2. The preamble of claim 1 and 2 respectively.

Solche Vorrichtungen sind bekannt, beispielsweise durch die deutsche Offenlegungsschrift 3 513 607 A1. Solche Anzeigevorrichtungen werden als Informationstableaus beispielsweise für Verkehrshinweise, Fahrpläne, Anzeigetafeln in Stadien und Arenen und dergleichen mehr verwendet.Devices of this type are known, for example from German Offenlegungsschrift 3 513 607 A1. Such display devices are used as information boards, for example for traffic information, Timetables, scoreboards in stadiums and arenas and the like are used.

Bei den Anzeigetafeln nach dem Stande der Technik, auf denen über längere Zeit sprich Größenordnung 10 Minuten beispielsweise ein Bild dargestellt wird, z. B. der Spielstand in einem Fußballstadion, und erfolgt dann anschließend ein Bildwechsel, so ist in dem neuen Bild das vorherige Bild als dunkle Überlagerung sichtbar.In the case of the display boards according to the prior art, on which the order of magnitude 10 over a long period of time Minutes, for example, an image is displayed, e.g. B. the score in a football stadium, and takes place then a change of picture, the previous picture in the new picture is a dark overlay visible.

Die Erfindung hat sich deshalb zur Aufgabe gestellt, daß bei einem Bildwechsel nach längerer Anzeigedauer eines vorherigen Bildes das alte Bild nicht mehr sichtbar bzw. erkennbar sein soll.The invention has therefore set itself the task that when changing the image after a long display time of a previous picture the old picture should no longer be visible or recognizable.

Diese Aufgabe wurde mit den kennzeichnenden Merkmalen des Anspruches 1 bzw. 2 gelöst.This object was achieved with the characterizing features of claims 1 and 2, respectively.

Vorteilhafte Ausgestaltungen ergeben sich durch die Unteransprüche.Advantageous refinements result from the subclaims.

Die Vorfeile der vorliegenden erfindungsgemäßen Anzeigevorrichtung liegen darin, daß bei einem Bildwechsel nach einer länger andauernden Anzeige eines ersten Bildes dieses nicht mehr erkennbar ist und damit nicht mehr stör. Außerdem wird im Falle der Dimmung die Gesamthelligkeit der Anzeigetafel etwa konstant gehalten.The advantages of the present display device according to the invention are that when changing the image after a longer display of a first picture it is no longer recognizable and therefore not more disturbing. In addition, in the case of dimming, the overall brightness of the display panel becomes approximately constant held.

Die erfindungsgemäße Lösung beruht auf der Erkenntnis, daß manche Leuchtdiodentypen eine starke Abhängigkeit der abgestrahlten Helligkeit von der Chiptemperatur aufweisen. Wenn eine Leuchtdiode über ein längere Zeit angesteuert wird, so erhöht sich die Chiptemperatur durch Abwärme, wodurch die Helligkeit verändert werden kann. Bei der momentanen LED-Technologie ist es so, daß eine sehr starke Abhängigkeit von der Chiptemperatur insbesondere die rotleuchtenden Leuchtdioden aufweisen, welche mit zunehmender Temperatur stark an Helligkeit verlieren. Bei grünen Leuchtdioden ist der Effekt nicht ganz so stark, während bei blauen Leuchtdioden der Effekt leicht umgekehrt ist, d. h. sie leuchten mit zunehmender Chiptemperatur etwas heller.The solution according to the invention is based on the knowledge that some types of light emitting diodes are strong Dependence of the emitted brightness on the chip temperature. If a light emitting diode has a Is controlled for a long time, the chip temperature increases due to waste heat, which increases the brightness can be changed. With the current LED technology it is a very strong dependency of the chip temperature, in particular the red light-emitting diodes, which increase with increasing Temperature is losing brightness. With green LEDs, the effect is not quite as strong, though with blue LEDs, the effect is slightly reversed, d. H. they glow with increasing chip temperature a little brighter.

Es folgt nun die Beschreibung anhand der Figuren. Die Fig. 1 veranschaulicht die Lösung gemäß Anspruch 1, während die Abb. 2 eine Softwarelösung oder Hardwarelösung gemäß Anspruch 2 darstellt. Die Fig. 1 zeigt den Ansteuerstrompfad einer Leuchtdiode LED an deren Kathode sich ein temperaturabhängiges Widerstandnetzwerk, bestehend aus einem temperaturabhängigen Widerstand TC und einem Vorwiderstand RV, sowie einem Parallelwiderstand RP anschließt.The description follows with the aid of the figures. Fig. 1 illustrates the solution in accordance with claim 1, while the Fig. 2 illustrates a software solution or hardware solution according to claim 2. Fig. 1 shows the driving current of a light emitting diode LED to the cathode of a temperature-dependent resistor network consisting of a temperature-dependent resistor connects TC and a series resistor RV, and a parallel resistance RP.

Die Fig. 2 zeigt ein Flußdiagramm gemischt mit einem Zeitdiagramm, wobei der Inhalt eines ersten Bildes (1), nämlich senkrecht stehender weißer Balken auf schwarzem Feld, und der Inhalt eines zweiten folgenden Bildes (3), nämlich ein liegender weißer Balken auf dunkelgrauem Feld dargestellt sind. Bis zum Zeitpunkt 11 soll das alte Bild dargestellt werden, ab dem Zeitpunkt t1 das neue Bild, also weißer Querbalken. Entsprechend der erfindungsgemäßen Lösung wird nunmehr das neue Bild (3) zusätzlich mit dem Bild (1), letzteres in abgeschwächter Form, angesteuert. Die Abschwächung (2) des alten Bildes wird dabei um so kleiner, je größer die Anzeigedauer des alten Bildes war. Dabei ist die Abschwächung angepaßt an die thermische Zeitkonstante der Leuchtdiode. Gleichzeitig wird das neu anzuzeigende Bild 3 ebenfalls abgeschwächt, wobei die Abschwächung (4) um so schwächer ausfällt, je länger das neue Bild angezeigt wird. Die Ergebnisse der beiden Abschwächungen (2) und (4) werden addiert durch den Adder (5) und als Bild (6) auf der Anzeigetafel dargestellt. Dabei wird die Abschwächung ständig an die laufende Anzeigedauer angepaßt. Die Bildinhalte (6a) bis (6c) sollen dabei den ständigen Anpassungsprozeß verdeutlichen. Zum Zeitpunkt t2 ist nunmehr die Abschwächung des alten Bildes auf 100% und die Abschwächung des neuen Bildes auf 0% gegangen, was bedeutet, daß das alte Bild nicht mehr und das neue Bild (7) nunmehr ohne Veränderung, siehe Bildinhalt (7), der mit Bildinhalt (3) identisch ist. FIG. 2 shows a flow diagram mixed with a time diagram, the content of a first image (1), namely a vertical white bar on a black field, and the content of a second following image (3), namely a lying white bar on a dark gray field are shown. The old image is to be displayed by time 11 , and the new image, that is to say white crossbar, from time t1. According to the solution according to the invention, the new image (3) is now additionally controlled with the image (1), the latter in a weakened form. The attenuation ( 2 ) of the old picture becomes smaller the longer the display time of the old picture was. The attenuation is adapted to the thermal time constant of the LED. At the same time, the newly displayed image 3 is also weakened, the weakening ( 4 ) being weaker the longer the new image is displayed. The results of the two weakenings ( 2 ) and ( 4 ) are added up by the adder ( 5 ) and shown as image (6) on the display board. The weakening is constantly adapted to the current display time. The image contents ( 6 a) to ( 6 c) are intended to illustrate the constant adaptation process. At time t2, the attenuation of the old image has now gone to 100% and the attenuation of the new image has gone to 0%, which means that the old image is no longer and the new image (7) is now unchanged, see image content ( 7 ), which is identical to the image content ( 3 ).

Falls die Anzeigetafel während der Zeiten t1 bis t2 gedimmt ist, kann zusätzlich auch auf den Dimmer eingewirkt werden, was zu einer zusätzlichen Stabilisierung und Konstanthaltung der Gesamthelligkeit führt. Hierbei würde die Dimmung in Abhängigkeit der Abschwächung (4) geregelt werden.If the display panel is dimmed during times t1 to t2, the dimmer can also be acted on, which leads to additional stabilization and keeping the overall brightness constant. The dimming would be regulated depending on the attenuation ( 4 ).

Die Abschwächungen sind entsprechend der Temperaturkurve der verschiedenen Leuchtdiodentypen auszuführen. Eine gute Wirkung wird auch erzielt, wenn eine Kompensation nur für zwei Farben (z. B. aus derzeitiger Sicht Rot und Grün) oder nur für eine Farbe durchgeführt wird, bei denen der eingangs geschilderte Effekt am stärksten auftritt.The attenuations correspond to the temperature curve of the different types of LEDs to execute. A good effect is also achieved if compensation is only for two colors (e.g. from current view red and green) or only for a color in which the input described effect occurs most strongly.

Effiziente Ergebnisse können auch durch bestimmte Kombinationen von Hardware- bzw. Softwarelösung gemäß den einzelnen Ansprüchen erzielt werden.Efficient results can also be achieved through certain combinations of hardware or software solutions can be achieved according to the individual claims.

Claims (11)

1. Vorrichtung zur Anzeige von Zeichen und Bildern mittels einer Vielzahl von Leuchtdioden, die nebeneinander matrixförmig auf einem Tableau angeordnet sind und zu einer in frontaler Richtungskeule erfolgenden Lichtabstrahlung erregbar sind, dadurch gekennzeichnet, daß in Abhängigkeit von der Innentemperatur und/oder der einzelnen Umgebungstemperatur der einzelnen Leuchtdiode deren Stromstärke bzw. zeitliche Stromansteuerung derart regelbar ist, so daß eine über der Zeit etwa konstante Helligkeit der Leuchtdiode erreicht wird.1. Apparatus for displaying characters and images by means of a plurality of light-emitting diodes, which are arranged next to one another in a matrix on a panel and can be excited to emit light in a frontal directional lobe, characterized in that depending on the internal temperature and / or the individual ambient temperature individual light-emitting diode whose current strength or temporal current control can be regulated in such a way that the brightness of the light-emitting diode is approximately constant over time. 2. Vorrichtung zur Anzeige von Zeichen und Bildern mittels einer Vielzahl von Leuchtdioden, die nebeneinander matrixförmig auf einem Tableau angeordnet sind und zu einer in frontaler Richtungskeule erfolgenden Lichtabstrahlung erregbar sind, dadurch gekennzeichnet, daß in Abhänigkeit von der Ansteuerdauer der einzelnen Leuchtdioden deren Stromanstärke bzw. zeitliche Stromansteuerung derart regelbar ist, so daß eine über der Zeit etwa konstante Helligkeit der Leuchtdiode erreicht wird.2. Device for displaying characters and images using a variety of light emitting diodes are arranged side by side in a matrix on a tableau and in a frontal directional lobe occurring light radiation are excitable, characterized in that depending on the Control duration of the individual light-emitting diodes, their current intensity or temporal current control in this way can be regulated so that an approximately constant brightness of the light-emitting diode is achieved over time. 3. Vorrichtung nach Anspruch 1, dadurch gekennzeichnet, daß ein temperaturabhäniger Widerstand (TC) in einem Widerstandsnetzwerk mit Serien-(RV) und/oder Parallelwiderstand (RP) in den Leuchtdiodenansteuerstrompfad eingefügt ist, daß das temperaturabhängige Widerstandsnetzwerk so dimensioniert ist, daß es die Helligkeit- /Temperaturkennlinie der Leuchtdiode (LED) aufgrund der Eigenerwärmung des temperaturabhängigen Widerstands etwa nahezu kompensiert und daß der temperaturabhängige Widerstand (TC) thermisch gut angekoppelt an die Leuchtdiode (LED) angebracht ist.3. Apparatus according to claim 1, characterized in that a temperature-dependent resistor (TC) in a resistance network with series (RV) and / or parallel resistance (RP) in the LED drive current path is inserted, that the temperature-dependent resistance network is dimensioned so that it / Temperature characteristic of the light-emitting diode (LED) due to the self-heating of the temperature-dependent Resistance almost compensated and that the temperature-dependent resistance (TC) is thermally good coupled to the light emitting diode (LED) is attached. 4. Vorrichtung nach Anspruch 1, dadurch gekennzeichnet, daß ein temperaturabhäniger Widerstand (TC) in einem Widerstandsnetzwerk mit Serien-(RV) und/oder Parallelwiderstand (RP) in den Leuchtdiodenansteuerstrompfad eingefügt ist, daß das temperaturabhängige Widerstandsnetzwerk so dimensioniert ist, daß es die Helligkeit- /Temperaturkennlinie der Leuchtdiode (LED) etwa nahezu kompensiert und daß der temperaturabhängige Widerstand (TC) thermisch gut angekoppelt an die Leuchtdiode (LED) angebracht ist.4. The device according to claim 1, characterized in that a temperature-dependent resistor (TC) in a resistance network with series (RV) and / or parallel resistance (RP) in the LED drive current path is inserted, that the temperature-dependent resistance network is dimensioned so that it / Temperature characteristic of the light-emitting diode (LED) almost compensated and that the temperature-dependent Resistor (TC) is thermally well coupled to the light emitting diode (LED). 5. Vorrichtung nach Anspruch 3, gekennzeichnet durch die Verwendung von NTC-oder TTC-Widerständen. 5. The device according to claim 3, characterized by the use of NTC or TTC resistors.   6. Vorrichtung nach Anspruch 2, dadurch gekennzeichnet, daß durch die ansteuernde Software und/oder Hardware der Bildinhalt bzgl. Leuchtdauer der einzelnen Leuchtdioden überwacht wird und daß in Abhängigkeit der Leuchtdauer der einzelnen Bildpunkte bei einem Bildwechsel gleichzeitig mit dem neuen Bildinhalt der alte Bildinhalt in abgeschwächter Form derart mit angesteuert wird, so daß der alte Bildinhalt summarisch nahezu eliminiert wird und nicht mehr sichtbar ist.6. The device according to claim 2, characterized in that by the controlling software and / or Hardware of the image content with regard to the light duration of the individual light emitting diodes is monitored and that depending on the light duration of the individual pixels when changing a picture simultaneously with the new image content, the old image content is also controlled in a weakened form, so that the old image content is virtually eliminated in summary and is no longer visible. 7. Vorrichtung nach Anspruch 6, dadurch gekennzeichnet, daß die mit Bildwechsel neu anzusteuernden Leuchtdioden einer Farbe dunkler und die bisher angesteuerten und durch neuen Bildinhalt weiterhin angesteuerten Leuchtdioden heller gesteuert werden.7. The device according to claim 6, characterized in that the new with picture change to be controlled light-emitting diodes of a color darker and the previously controlled and by new image content continues to be controlled brighter LEDs. 8. Vorrichtung nach Anspruch 6, dadurch gekennzeichnet, daß die mit Bildwechsel neu anzusteuernden Leuchtdioden einer Farbe heller und die bisher angesteuerten und durch neuen Bildinhalt weiterhin angesteuerten Leuchtdioden dunkler gesteuert werden.8. The device according to claim 6, characterized in that the to be controlled with image change Light-emitting diodes of one color are brighter and the ones that have been activated so far and continue with new image content controlled LEDs can be controlled darker. 9. Vorrichtung nach Anspruch 7, gekennzeichnet durch die Verwendung einer Dimmung des Tableaus, die derart steuerbar ist, daß die Gesamthelligkeit bei gedimmten Betrieb etwa konstant gehalten wird.9. The device according to claim 7, characterized by the use of a dimming of the panel, the is controllable in such a way that the overall brightness is kept approximately constant during dimmed operation. 10. Vorrichtung nach Anspruch 1 oder 2, gekennzeichnet durch die folgende Kombination: durch die ansteuernde Software und/oder Hardware wird der Bildinhalt bzgl. Leuchtdauer der einzelnen Leuchtdioden überwacht, in Abhängigkeit der Leuchtdauer der einzelnen Bildpunkte bei einem Bildwechsel gleichzeitig mit dem neuen Bildinhalt wird der alte Bildinhalt in abgeschwächter Form derart mit angesteuert, so daß der alte Bildinhalt summarisch nahezu eliminiert wird und nicht mehr sichtbar ist, und es wird die Dimmung des Tableaus verwendet, die derart steuerbar ist, daß die Gesamthelligkeit, etwa konstant gehalten wird.10. The device according to claim 1 or 2, characterized by the following combination: by the Controlling software and / or hardware becomes the image content with regard to the lighting duration of the individual LEDs monitor, depending on the light duration of the individual pixels at one Image change at the same time as the new image content, the old image content becomes such in a weakened form also controlled so that the old image content is virtually eliminated in summary and is no longer visible and the dimming of the panel is used, which is controllable in such a way that the overall brightness, is kept approximately constant. 11. Vorrichtung nach Anspruch 7, dadurch gekennzeichnet, daß die LED eine rotleuchtende Diode ist.11. The device according to claim 7, characterized in that the LED is a red glowing diode.
DE19933735A 1999-07-19 1999-07-19 LED display board with regulation of current to LEDs to provide constant brightness Withdrawn DE19933735A1 (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010054650A1 (en) * 2008-11-14 2010-05-20 Osram Opto Semiconductors Gmbh Optoelectronic device
WO2012044169A1 (en) * 2010-09-29 2012-04-05 European Intelligence B.V. Intrinsically safe display device with an array of leds
CN106782308A (en) * 2017-02-10 2017-05-31 上海天马有机发光显示技术有限公司 A kind of organic light emission circuit structure with temperature compensation function

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010054650A1 (en) * 2008-11-14 2010-05-20 Osram Opto Semiconductors Gmbh Optoelectronic device
US9398664B2 (en) 2008-11-14 2016-07-19 Osram Opto Semiconductors Gmbh Optoelectronic device that emits mixed light
WO2012044169A1 (en) * 2010-09-29 2012-04-05 European Intelligence B.V. Intrinsically safe display device with an array of leds
CN103229594A (en) * 2010-09-29 2013-07-31 欧洲智能有限公司 Intrinsically safe display device with an array of LEDs
AU2011308136B2 (en) * 2010-09-29 2015-09-03 European Intelligence B.V. Intrinsically safe display device with an array of LEDs
CN103229594B (en) * 2010-09-29 2016-08-17 欧洲智能有限公司 There is the intrinsic safety type display device of LED array
CN106782308A (en) * 2017-02-10 2017-05-31 上海天马有机发光显示技术有限公司 A kind of organic light emission circuit structure with temperature compensation function
US10504977B2 (en) 2017-02-10 2019-12-10 Shanghai Tianma AM-OLED Co., Ltd. Organic light-emitting circuit structure having temperature compensation function

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