CN211879407U

CN211879407U - Color-adjustable OLED light-emitting module

Info

Publication number: CN211879407U
Application number: CN202020136502.8U
Authority: CN
Inventors: 高亮; 庞惠卿; 谢梦兰
Original assignee: Beijing Xiahe Technology Co ltd
Current assignee: Beijing Xiahe Technology Co ltd; Beijing Summer Sprout Technology Co Ltd
Priority date: 2020-01-22
Filing date: 2020-01-22
Publication date: 2020-11-06
Anticipated expiration: 2030-01-22

Abstract

Disclosed is an OLED light emitting module with adjustable color. The module comprises an OLED light-emitting group and an external electric drive; the OLED light-emitting group at least comprises a first OLED light-emitting group and a second OLED light-emitting group; the OLED light-emitting group comprises OLED devices; the OLED device comprises an anode layer, a cathode layer, and an organic layer arranged therebetween, and has a light-emitting area; the organic layer comprises at least first and second light-emitting layers emitting first and second intrinsic peak wavelengths, respectively, which differ by at least 30 nm; external electric drive energy supplyThe first and second OLED light emitting groups provide current to light emitted from the OLED device having first and second color coordinate points, respectively, (u)₁，v₁) And (u)₂，v₂) (ii) a And duv between two coordinate points is greater than 0.01. The OLED light-emitting module can change the working current density of the device by adjusting the light-emitting area and/or the working current, so that the function of color adjustment is realized.

Description

Color-adjustable OLED light-emitting module

Technical Field

The invention relates to an OLED light-emitting module. And more particularly, to a color tunable OLED lighting module.

Background

An organic electroluminescent device (OLED) is formed by stacking a cathode, an anode, and an organic light emitting material between the cathode and the anode, converts electric energy into light by applying a voltage across the cathode and the anode of the device, and has advantages of a wide angle, a high contrast, and a faster response time. Tang and Van Slyke of Issman Kodak in 1987 reported an organic light emitting device with an arylamine hole transport layer and a tris-8-hydroxyquinoline-aluminum layer as an electron transport layer and a light emitting layer (Applied Physics letters, 1987,51(12): 913-915). The invention lays a foundation for the development of modern Organic Light Emitting Diodes (OLEDs). OLEDs have the advantages of low cost, low power consumption, high brightness, wide viewing angle, thin thickness, etc., and have been widely used in the display and lighting fields through decades of development.

In the field of lighting, light sources can be divided into cold color light sources and warm color light sources, with the cold and warm light being determined primarily by the color temperature of the light source. The cold light is a bluish light with a color temperature exceeding 4000K, and the warm light is a reddish light with a color temperature below 4000K. The requirements of people for color temperature are also different in different environments and applications, for example, asian regions generally favor cold color light sources, while european and american regions favor warm color light sources. In addition, a cold light source is generally used in an office or the like, and a warm light source is generally used in an environment such as a bedroom or the like. Nevertheless, many commercial illuminators have been capable of color temperature adjustment to achieve the function of emitting light of different color temperatures on different occasions. Therefore, it is a trend of general illumination to use the same light source to convert in different color temperatures. On the other hand, the light source with variable color has many applications in the field of car lights, for example, the tail light, turn signal light, brake light, and back-up light of the car are usually different in red, orange or white, and the brightness is also different, so that a single light source capable of emitting these colors at the same time is very popular. Patent CN209213730 discloses a color-changeable vehicular lamp, which is characterized in that a layer of electrochromic material is added into a transparent conductive layer, and the electrochromic material is controlled to generate color change by powering on and powering off the upper and lower transparent conductive layers. However, this method can only produce simple colors such as transparency, haze, black, etc., and this material brings about color change and also lowers the luminous efficiency. How to use a single light source for color change without reducing the luminous efficiency is one of the current attention directions of new vehicular lamps (M.M u gge, adv. opt. techn.2016; 5(2): 117-.

As mentioned above, color-tunable light fixtures are popular in the market, and displays or products with OLED light-emitting panels as light sources can also be found in the market. (https://www.oled-info.com/konica-minolta-show-color- tunable-thin-flexible-oled-lighting-panels). Vebatim Velve OLED panels from Mitsubishi are commercially available, which have color temperatures (CCT) that can be adjusted from 2700K to 6500K, encompassing a wide range of colors (VelveOLED lighting crochure, https:// www.oled-info. A color tunable white OLED light-emitting panel incorporating a fuse to improve yield is also disclosed in patent US8,836,223. However, all of these panels use red, green, blue (RGB) pixels or stripes to form the color toning function. This configuration requires the use of photolithography, which is a costly and complex process step. In addition, the red, green and blue edge-to-edge mode on one substrate means that the evaporation of the organic layers of three colors needs to be completed in one operation. In this case, a fine reticle is typically used to distinguish each color with high precision alignment. It is clear that such high device performance comes at the expense of increased process cost and complexity. In addition, the yield of these rgb arrayed light emitting panels can be a major concern due to the complexity of the process and the use of patterned reticles. Even with the fuse design (US8,836,223), a light-emitting panel is still considered NG (Not Good, bad) when its number of bad pixels reaches 5%. Finally, because each stripe or group of color stripes are driven independently, the driving circuit is more complex and the whole module package becomes very bulky. For example, the Verbatim light panel requires a PCB controller such that the entire module is 8.7mm thick and the light panel itself is 3.9 mm.

Another approach to constructing color tunable light emission is to use tandem structures (tandem structures), or vertically stacked OLEDs. Since the first concept of stacked OLEDs was proposed (Burrows, appl. phys. lett.69(20),11Nov,1996), many have focused on the use of similar structures to achieve multi-color modulation in the display and illumination fields (US 5,757,026, US 7,948,165, US5,837,391, US 7,750,561, US 6,166,489, US 9,634,293). One common solution is to grow a plurality of different colored OLED cells in a longitudinal direction on a single substrate and use a charge generating layer (to achieve a fixed color) or sometimes an insulating layer (to achieve an independently adjustable color) between the cells. A clear advantage is that the overall device can be thin because the total thickness of the OLED cells does not exceed the micron level, and it is possible in some applications to reduce process cost and complexity by eliminating the use of fine reticles. However, these multi-layer structures are usually fabricated on the same substrate, and are driven independently by using insulating layers and vias between layers, which greatly increases the process complexity and causes problems of process mismatch, reduced yield, and the like.

On the basis of the above, CN109253404A proposes to bond at least two OLED light-emitting panels of different colors to achieve color tunability. This approach avoids the complex process of integrating different colors within one device structure, but also makes the final product massive and loses luminous efficiency due to the use of transparent devices.

Patent CN110274163A discloses an OLED lighting device capable of adjusting color temperature of white light, which combines an LED and an OLED, wherein the LED is used for emitting a blue light source, the OLED is used for emitting light with warm color temperature, and the purpose of adjusting color temperature is achieved by adjusting the light emitting intensity of the LED and the OLED.

To ensure the light and thin characteristics of the final product, the integration of different light emitting layers in a single OLED device is a promising candidate. In the organic material of the OLED, the mobility of holes is much larger than that of electrons, and the change trend of the injection of electrons and the injection of holes under different operating currents is also very different, and the injection of electrons is much more rapid than that of holes with the increase of operating current, so that in the OLED, the recombination region in the light-emitting layer moves from the side adjacent to the electron transport layer to the side adjacent to the hole transport layer with the increase of current density (Kyoung Soo Yook, Journal of Industrial and engineering Chemistry, Volume 16, Issue 2,2010, Pages 181-. For a white OLED with an independent-unit multi-luminescent-layer structure, when the driving voltage is increased, the center of the recombination region may shift from one color luminescent layer to another color luminescent layer, so that the ratio of the light intensities of different colors changes, for example, when the ratio of blue light is increased, the emitted light is in a cool tone, and when the ratio of red light is increased, the emitted light is in a warm tone. By utilizing the characteristic, the color temperature of the OLED illumination light source can be changed. Note that this device structure is fundamentally different from a stacked device using a charge generation layer. Firstly, in a laminated device, the device structure in each light-emitting unit is relatively complete, namely, the light-emitting units are provided with electron and hole transport layers which appear in pairs, and a plurality of light-emitting units are provided with a plurality of pairs of electron and hole transport layers; in the device structure of the independent unit multi-luminescent layer described above, although the luminescent layer may be plural, the electron and hole transport layers are only paired. Secondly, charge generation layers CGL are used in different light emitting units in the stacked device, which are essentially a combination of a pair of p-type and n-type conductive materials, and need to be used adjacent to electron transport/injection and hole transport/injection layers, respectively, often requiring the use of metals or metal compounds; the regulating layer used in the device of the independent unit multiple light emitting layer is usually an electron or hole blocking layer material, is an organic material, and is used next to the two light emitting layers. The most essential difference is that in a stacked device using CGL, the recombination regions of carriers do not move in different light emitting layers but are relatively fixed in the respective light emitting layers, and thus the color remains substantially unchanged even if the current density changes; while the recombination regions of carriers in the independent unit multiple light emitting layers move in different light emitting layers as the current density changes, so that color shifts appear.

In patent CN103000822, it is disclosed that a white color ink using blue, green, yellow and red four dyes doped two by two in two different host materials for realizing adjustable color temperatureThe organic OLED device forms different exciton recombination regions according to different applied voltages so as to realize the conversion from cold white light to warm white light, but the device has a complex structure, the brightness can change along with the voltage change, and the implementation cost is high. In patent US5773130, an organic electroluminescent device is disclosed which can emit a plurality of colors, and the device can emit two spectra having different peaks depending on the applied voltage, but the peaks of the two spectra differ by only 20nm, and the spectral range of the variable color is narrow. And the difference of the driving current densities required by the two spectra is 600 mA/cm²The above causes a great difference in brightness, and is not practical. In patent CN105742520A, a color-changing OLED device is disclosed, which comprises two ultrathin light-emitting layers and an energy transfer regulating layer therebetween, wherein the regulating layer is a host organic material. The above patents are limited to a single OLED device structure and do not encompass the combination of multiple devices and their particular applications. The invention focuses on the combination of a plurality of OLED lighting groups and a plurality of OLED devices comprised thereby.

The above variable color OLED light emitting panel only looks at a single OLED and all face the problem of brightness difference due to current density difference. In reality, however, the total luminous flux is more meaningful than the brightness. For a surface light source such as an OLED, the luminous flux is proportional to the product of the luminance and the light emitting area. This means that low brightness can be compensated for by a larger light-emitting area in order to keep the same luminous flux constant. And different colors corresponding to different light emitting areas are widely applied in reality. For example, the luminous panels with different colors and different areas are arranged according to a certain rule and can be used for displaying the oil quantity or the electric quantity of the automobile (http://m.elecfans.com/article/768341.html). An illumination module using a plurality of OLED panels with different light emitting surfaces is also disclosed in US8,552,420, but in this invention all OLED panels emit light of the same color and the purpose is to achieve a staggered brightness effect for generating different brightness, which is essentially different from the purpose of adjusting the light emitting color of the present invention.

The invention discloses a light-emitting module, which realizes the function of adjustable color by adjusting the light-emitting area and/or the working current to change the working current density of a single device.

Disclosure of Invention

In view of the above problems, the present invention is directed to a novel color tunable organic electroluminescent device module to solve at least some of the above problems.

According to one embodiment of the invention, the invention discloses an OLED light-emitting module with adjustable color, which is characterized by comprising an OLED light-emitting group and an external electric drive;

wherein the OLED light-emitting groups comprise at least a first OLED light-emitting group and a second OLED light-emitting group;

the first OLED light-emitting group comprises at least one OLED light-emitting device and a first light-emitting surface, and the first light-emitting surface is provided with a first light-emitting area;

the second OLED light-emitting group comprises at least one OLED light-emitting device and a second light-emitting surface, and the second light-emitting surface has a second light-emitting area;

wherein the OLED light emitting device comprises an anode layer, a cathode layer, and a plurality of organic layers disposed between the cathode layer and the anode layer;

wherein the organic layer of the OLED light-emitting device comprises at least two light-emitting layers;

wherein the at least two light emitting layers comprise a first light emitting layer and a second light emitting layer, wherein the first light emitting layer emits a first intrinsic peak wavelength and the second light emitting layer emits a second intrinsic peak wavelength, the first intrinsic peak wavelength and the second intrinsic peak wavelength differing by at least 30 nm;

wherein the external electric drive energy provides a first current to the first OLED light-emitting group, so that the light emitted by at least one OLED device in the first OLED light-emitting group has a first color coordinate point (u) on the CIE 1976 color coordinate diagram₁，v₁)；

Wherein the external electrical drive energy provides a second current to the second OLED light emitting group such that the light emitted from at least one OLED device in the second OLED light emitting group has a second color coordinate point (u) on the CIE 1976 color coordinate diagram₂，v₂)；

Wherein a duv value between the first color coordinate point and the second color coordinate point is greater than 0.01.

According to another embodiment of the present invention, a consumer product is disclosed, the consumer product comprising a color tunable OLED lighting module comprising an OLED lighting group and an external electrical drive;

The invention discloses a light-emitting module, which utilizes the movement of an exciton recombination region under different current densities in a single OLED device to regulate and control the color, combines a plurality of OLED devices into the light-emitting module, and changes the working current density of the single device by regulating the light-emitting area and/or the working current so as to realize the function of color adjustment.

Drawings

Fig. 1a-1b are schematic cross-sectional views of a color tunable OLED light emitting device.

Fig. 2a-2d are schematic views of a color-tunable OLED light-emitting panel.

FIGS. 3a-3b are schematic circuit diagrams of the color tunable OLED lighting module of example 1.

FIGS. 4a-4d are schematic circuit diagrams of the color tunable OLED lighting module of example 2.

FIGS. 5a-5f are schematic circuit diagrams of the color tunable OLED lighting module of example 3.

FIGS. 6a-6c are schematic circuit diagrams of the color tunable OLED lighting module of example 4.

FIG. 7 is a plot of the CIE 1931 color coordinates of an OLED light emitting panel as a function of applied voltage.

Detailed Description

As used herein, "top" means furthest from the substrate, and "bottom" means closest to the substrate. In the case where the first layer is described as being "disposed on" the second layer, the first layer is disposed farther from the substrate. Other layers may be present between the first and second layers, unless it is specified that the first layer is "in contact with" the second layer. For example, a cathode can be described as being "disposed on" an anode even though various organic layers are present between the cathode and the anode.

As used herein, the term "OLED device" includes an anode layer, a cathode layer, one or more organic layers disposed between the anode layer and the cathode layer. An "OLED device" can be bottom emitting, i.e. from the substrate side, or top emitting, i.e. from the encapsulation layer side, or a transparent device, i.e. from both the substrate and the encapsulation side.

As used herein, the term "OLED light emitting panel" includes a substrate, an anode layer, a cathode layer, one or more organic layers disposed between the anode layer and the cathode layer, an encapsulation layer, and at least one anode contact and at least one cathode contact extending outside of the encapsulation layer for external access. An "OLED light-emitting panel" has more substrates, encapsulation layers, and electrical contacts than an "OLED device". The OLED light-emitting panel can comprise a plurality of OLED devices which can be independently packaged, can share the same packaging layer, can be lightened or extinguished at the same time, and can be selectively lightened or extinguished by simple metal connecting wires and external circuit control; an "OLED light-emitting panel" may also comprise only a single "OLED device", for example, an "OLED light-emitting panel" comprising a plurality of "OLED devices" may be cut such that each "OLED device" is independently controllable, in which case the "OLED light-emitting panel" comprises only one "OLED device".

As used herein, the term "module" refers to an electronic device having only one set of external electrical drives.

As used herein, the term "externally electrically driven" refers to a system of devices that can power a module, which typically includes a circuit control system and an external power source. The circuit control system may include, but is not limited to, cathode and anode electrical contacts, wires, FPC boards, integrated circuits, transformers, etc.; the external power supply can be various batteries directly, or can be a charger connected with alternating current through a socket, or other electronic equipment connected with a USB interface, or can be a power generator connected with the power supply through a wire, and the like.

As used herein, the term "encapsulation layer" may be a thin film encapsulation having a thickness of less than 100um, which includes disposing one or more thin films directly onto the device, or may also be a cover glass (cover glass) adhered to a substrate.

As used herein, the term "flexible printed circuit" (FPC) refers to any flexible substrate coated with any one or combination of the following, including but not limited to: conductive lines, resistors, capacitors, inductors, transistors, micro-electro-mechanical systems (MEMS), and the like. The flexible substrate of the flexible printed circuit may be plastic, thin glass, thin metal foil coated with an insulating layer, fabric, leather, paper, etc. A flexible printed circuit board is typically less than 1mm thick, more preferably less than 0.7mm thick.

As used herein, the term "light extraction layer" may refer to a light diffusing film, or other microstructure having light extraction effects, or a thin film coating having light outcoupling effects. The light extraction layer can be disposed on the substrate surface of the OLED, or can be in other suitable locations, such as between the substrate and the anode, or between the organic layer and the cathode, between the cathode and the encapsulation layer, on the surface of the encapsulation layer, and so forth.

As used herein, the term "light-emitting area" refers to the portion of the planar area where the anode, organic layer and cathode are co-incident, excluding light extraction effects. The "light emitting area" does not include edge light emission and does not represent a hemispherical light emitting space in three dimensions. Each OLED device has a light emitting area. In this context, the first light-emitting area refers to the total light-emitting area of all OLED devices of the first light-emitting group, and similarly, the second light-emitting area refers to the total light-emitting area of all OLED devices of the second light-emitting group.

As described herein, a "light emitting group" may include only one OLED light emitting device, or may include a plurality of OLED light emitting devices. In addition, the same OLED light emitting device can belong to a plurality of different light emitting groups at the same time. When the OLED light emitting devices in a light emitting group are operated, the current densities of the OLED light emitting devices in the light emitting group may be the same or different.

As used herein, the "color rendering index" (CRI) is a reference light source that uses sunlight as a standard, and is used to measure the degree of color distortion of an object under illumination by other light sources, assuming that the color of the object is a true color in sunlight, and the color rendering index is 100. For example, the color rendering index of an incandescent lamp is 95-100, which means that the object is distorted to a small extent by the illumination of the incandescent lamp and the displayed color is close to that of the object in daylight. The current standard requires that the color rendering index of a white light illumination fixture be greater than 80.

As used herein, "color temperature" is a unit of measure representing the color component contained in a light ray. Theoretically, the blackbody temperature refers to the color that an absolute blackbody would appear after warming from absolute zero (-273 ℃). After being heated, the black body gradually turns from black to red, turns yellow and becomes white, and finally emits blue light. When heated to a certain temperature, the light emitted by a black body contains spectral components, referred to as the color temperature at that temperature, measured in "K" (kelvin). A certain light source emits light having the same spectral composition as that of light emitted from a black body at a certain temperature, and is called a certain K color temperature. If the color of the light emitted from a 100W incandescent bulb is the same as the color of an absolute black body at 2527K, then the color temperature of the light emitted from this bulb is: (2527+273) K2800K.

As used herein, "duv" is an indicator used to quantify the difference in color between different light sources, and is specified in the present invention as the distance between two color coordinate points on the CIE 1976 color coordinate diagram. For example, the first color coordinate point on the CIE 1976 color coordinate diagram is (u)₁,v₁) Second color coordinate position (u)₂,v₂) Then duv ═ sqrt [ (u)₁-u₂)²+(v₁-v₂₎ ²]。

As used herein, "intrinsic peak wavelength" refers to the peak wavelength emitted by an organic light emitting material in a bottom-emitting device comprising at least an anode layer, a hole injection layer, a hole transport layer, an electron injection layer, and a cathode layer. Under different matched material systems, the intrinsic peak wavelength of the luminescent material can have certain difference, but all should be within the range of +/-10 nm.

As used herein, "organic layers have the same structure" means that the organic layers of different OLED devices are made from the same material, and that the thickness of each layer of material is within +/-10%, and the weight of each material is within +/-10% if it is a doped layer.

According to one embodiment of the invention, the invention discloses a color-adjustable OLED light-emitting module which is characterized by comprising an OLED light-emitting group and an external electric drive;

An embodiment according to the invention is characterized in that the first and second current intensities are different, or in that the first and second light emitting areas are different, or in that the first and second current intensities, the first and second light emitting areas are both different.

An embodiment according to the invention is characterized in that the first current and the second current are of the same intensity, while the first light emitting area and the second light emitting area are different.

An embodiment according to the invention is characterized in that the first and second currents are of different intensity, while the first and second light emitting areas are different or identical.

An embodiment according to the invention is characterized wherein the organic layers in the OLED light emitting device have the same structure.

An embodiment according to the invention is characterized wherein the first intrinsic peak wavelength and the second intrinsic peak wavelength differ by at least 50 nm.

An embodiment according to the invention is characterized wherein the first intrinsic peak wavelength and the second intrinsic peak wavelength differ by at least 80 nm.

An embodiment according to the invention is characterized wherein the first intrinsic peak wavelength and the second intrinsic peak wavelength differ by at least 100 nm.

An embodiment according to the invention is characterized wherein the organic layer of the OLED light emitting device further comprises a third light emitting layer, wherein the third light emitting layer comprises a third intrinsic peak wavelength and the third intrinsic peak wavelength differs from the first and second intrinsic peak wavelengths by at least 30 nm.

An embodiment according to the invention is characterized in that the organic layer of the OLED light emitting device further comprises a regulating layer, wherein the regulating layer is arranged between adjacent light emitting layers.

In this embodiment, "the adjustment layer is provided between adjacent light emitting layers" means that the adjustment layer is provided between two adjacent light emitting layers. For example, if there is no other light-emitting layer between the first light-emitting layer and the second light-emitting layer, the first light-emitting layer and the second light-emitting layer are considered to be adjacent to each other, and the adjustment layer may be provided between the first light-emitting layer and the second light-emitting layer; similarly, if the third light emitting layer and the second light emitting layer are adjacent, the adjusting layer may be disposed between the second light emitting layer and the third light emitting layer.

An embodiment according to the invention is characterized in that at least one of the OLED light emitting devices belongs to both the first light emitting group and the second light emitting group.

An embodiment according to the invention is characterized in that the first light emitting group and the second light emitting group are operated simultaneously or alternately.

In this embodiment, "the first light emitting group and the second light emitting group are simultaneously operated" means that the external electric drive supplies the first current to the first light emitting group while supplying the second current to the second light emitting group, so that the first light emitting group and the second light emitting group are simultaneously operated. The "first light emitting group and the second light emitting group are alternately operated" means that external electric drive only provides a first current to the first light emitting group and does not provide a second current to the second light emitting group, and at the moment, the first light emitting group is operated and the second light emitting group is not operated; or external electric drive only provides the second current for the second light-emitting group, but does not provide the first current for the first light-emitting group, and at the moment, the first light-emitting group does not work, and the second light-emitting group works.

An embodiment according to the invention is characterized in that the first and second light emitting facets may be regular or irregular in shape.

An embodiment according to the invention is characterized in that at least two of the OLED light emitting devices have the same or different light emitting areas.

An embodiment according to the invention is characterized in that at least two OLED light emitting devices in the first light emitting group are connected in series or in parallel; wherein at least two OLED light emitting devices in the second light emitting group are connected in series or in parallel.

An embodiment according to the invention is characterized wherein at least one OLED device in the first light emitting group and at least one OLED device in the second light emitting group are connected in series or in parallel.

An embodiment according to the invention is characterized in that at least two of the OLED light emitting devices are on the same substrate.

An embodiment according to the invention is characterized in that the OLED light emitting devices are all on the same substrate.

According to one embodiment of the present invention, the first color coordinate point and the second color coordinate point have a duv value greater than 0.05.

According to one embodiment of the present invention, the first color coordinate point and the second color coordinate point have a duv value greater than 0.1.

An embodiment according to the invention is characterized in that the color-tunable OLED lighting module further comprises a resistive element.

An embodiment according to the invention is characterized in that the material of the resistive element is one of anode layer material, cathode layer material, metal, transparent oxide, FPC lead material or a combination thereof.

An embodiment according to the invention is characterized in that the OLED light emitting device emits white light, and the adjustable range of the color temperature at different current densities is 2000K-9000K.

According to an embodiment of the invention, a consumer product is further disclosed, wherein the consumer product comprises the color-tunable OLED lighting module of any of the above embodiments.

Light emitting modules prepared according to embodiments of the present invention can be incorporated into various consumer products having one or more electronic component modules (or units) of the device. Some examples of such consumer products include flat panel displays, monitors, medical monitors, televisions, billboards, lights for indoor or outdoor lighting and/or signaling, head-up displays, fully or partially transparent displays, flexible displays, smart phones, tablet computers, tablet handsets, wearable devices, smart watches, laptop computers, digital cameras, camcorders, viewfinders, micro-displays, 3-D displays, vehicle displays, and tail lights.

FIG. 1a shows, schematically and without limitation, a cross-sectional view of a color-tunable OLED light-emitting device 100 comprising two light-emitting layers. The figures are not necessarily to scale, and some of the layer structures in the figures may be omitted as desired. The OLED light emitting device 100 includes an anode 101, a hole injection layer 102, a hole transport layer 103, an electron blocking layer 104, a first light emitting layer 105, a first adjusting layer 106, a second light emitting layer 107, a hole blocking layer 108, an electron transport layer 109, an electron injection layer 110, a cathode 111, and a coverLayer 112. Wherein the electron blocking layer 104, the adjusting layer 106, the hole blocking layer 108, and the capping layer 112 are optional layers. A color-tunable OLED light emitting device may further comprise a second adjusting layer 113 and a third light emitting layer 114 on top of the second light emitting layer 107, as shown in fig. 1b, also the second adjusting layer 114 is an optional layer. The light emitting materials of the light emitting layers can be selected according to actual needs, for example, the two light emitting layers shown in fig. 1a can be the blue light emitting layer 105 and the yellow light emitting layer 107, respectively, and the three light emitting layers shown in fig. 1b can be the blue light emitting layer 105, the green light emitting layer 107, and the red light emitting layer 114, respectively. When the injected current is increased from small to large at two ends of the device, the recombination region can gradually move from the electron transmission end to the hole transmission end, and the light intensity proportion emitted by different light emitting layers is changed. Taking fig. 1b as an example, at low current density, the recombination region is concentrated in the red light emitting layer 114, and the spectrum of red light is more, so the OLED light emitting device emits warm white light. After the current density is increased, the recombination region moves to the green light-emitting layer 107 and then to the blue light-emitting layer 105 in sequence, the light intensity of green and blue in the spectrum is increased, the light emitted by the OLED light-emitting device gradually deflects to blue, and cold white light is emitted. It should be noted that a very thin layer (usually not thicker than the thickness of the luminescent layer) can be added between the different luminescent layers

Preferably not more than

) The adjusting layer is usually a hole blocking material or an electron blocking material, so that the number of holes or electrons in different recombination areas is limited, and the light emitting proportion of different light emitting layers is controlled. Nevertheless, the adjustment layer is not essential, and may be adjusted, for example, by matching the energy levels of the host materials of the different light emitting layers. Note that in CN105742520A, a control layer of host material is required between two light-emitting layers and has a thickness of

Far thicker than meThe material properties of the regulating layers used therein are also different.

A cross-sectional view of a color-tunable OLED light-emitting panel is shown in fig. 2 a. The OLED light-emitting panel 300 comprises a substrate 301, a color tunable OLED device 310, a pair of contact electrodes 303 electrically connected to the OLED device 310, a thin film encapsulation layer 302 exposing the contact electrodes 303, and an adhesive structure 304 connecting the pair of contact electrodes 303 to external driving circuitry. The substrate 301 may be rigid, such as glass, or flexible, such as plastic. Color-tunable OLED device 310 can be a bottom emitting device, a top emitting device, or a transparent device, i.e., both sides can emit light. The encapsulation layer 302 may be a glass cover slip that is glued to the substrate by an adhesive. Alternatively, the encapsulation layer 302 may be a thin film encapsulation layer, such as thin film glass, a single inorganic layer, or an organic-inorganic alternating multilayer structure. The contact electrode 303 may comprise at least one anode contact and one cathode contact. A front cover film 305 may be added to the basic OLED light-emitting panel 300 as shown in fig. 2 b. The front cover film 305 may be a Flexible Printed Circuit (FPC) board on which a pre-designed circuit is printed and electrically connected to the OLED device 310 through the adhesive structure 304. In another alternative, the adhesive structure 304 may be an FPC frame and the front cover film 305 may be a sheet of plastic film to provide mechanical support. A specific description of the use of an FPC board to drive an OLED light-emitting panel can be found in chinese patent application CN108644628A, which is incorporated by reference in its entirety and is not within the scope of coverage of this application. The front cover film 305 may also include a light extraction layer. When OLED device 310 is top-emitting, front cover film 305 may be transparent in the light-emitting area. The front cover film 305 may be a combination of the above. Additional thin film encapsulation layers 306 may be applied to one or both sides of the substrate 301 as shown in fig. 2 c. The front cover film may also be coated with an additional thin film encapsulation layer 306, but is not shown in this figure. In fig. 2d, a back cover film 307 is overlaid onto the substrate 301. The back cover film 307 may be used for mechanical support. When the OLED is a bottom emission device, the back cover film 307 may be a light extraction layer. The back cover film 307 may be a combination of the above. The color-tunable OLED light-emitting panel is a framework base of the color-tunable OLED light-emitting module.

The OLED light-emitting panel with adjustable color can comprise a plurality of OLED devices with adjustable color, the OLED devices can be independently packaged, can share the same packaging layer, can be simultaneously lightened or extinguished, and can be selectively lightened or extinguished by simple metal connecting wires and external circuit control; a color-tunable OLED light-emitting panel may also comprise a single OLED device, for example a light-emitting panel comprising a plurality of OLED devices cut such that each OLED device is individually controllable, in which case the light-emitting panel comprises only one OLED device. A plurality of color-tunable light-emitting panels or devices may be combined into a light-emitting group, which may itself be a light-emitting group when a plurality of OLED devices are included in a light-emitting panel, although it is still possible to combine a plurality of such panels into a larger light-emitting group. While the color-tunable OLED devices on all light-emitting panels have the same device structure, in particular the organic layer structure. By "the same device structure" is meant that the organic layers in different devices are made of the same material, and that the thickness of each layer of material is within +/-10%, and in the case of doped layers the weight of each material is within +/-10%. Each device used in the color tunable OLED lighting module has a light-emitting area, which may be the same or different from each other, and may be of a regular geometric shape or an irregular shape (such as the oil indicator mentioned above). Each light-emitting group in the light-emitting module has a light-emitting area which is the sum of the light-emitting areas of all OLED devices in the light-emitting group.

Examples

The working principle of the color tunable light emitting module using exciton recombination region movement is illustrated below. The OLED devices used in all the following examples are device structures of the independent unit multi-luminescent layer described above, and their emission colors vary with the current density. Hereinafter, the present invention will be described in more detail with reference to the following examples. It is apparent that the following examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Based on the following examples, a person skilled in the art will be able to modify them in order to obtain further embodiments of the invention.

Example 1.

The color-tunable OLED lighting module is composed of at least two color-tunable

OLED lighting devices

1101 and 1102 and a control switch 1103, and fig. 3a and 3b show a circuit schematic diagram of the combination, where the

OLED lighting devices

1101 and 1102 are connected in parallel through the control switch 1103, the lighting areas of the two devices are the same and assumed to be a, and the two lighting devices have the same device structure. In example 1, the first light emission group includes only OLED light emitting device 1101, and the second light emission group includes OLED

light emitting devices

1101 and 1102. In a first operating state (fig. 3a), the control switch 1103 on the lighting module is open, and the total current I is input by an external electrical drive (not shown in fig. 3a)₁The first light emitting group is enabled to operate, that is, the OLED light emitting device 1101 emits light, and the current passing through the OLED device 1101 at this time is the total current I₁At a current density of J₁＝I₁A, corresponding voltage V₁I.e. the total voltage, the emitted brightness is L₁Having a first luminescent color coordinate C on the 1976CIE color coordinate diagram₁＝(u₁， v₁) Total luminous flux of the first light-emitting group phi₁Proportional to the product phi of brightness and area₁＝2πL₁A. In a second operating state (fig. 3b), the control switch 1103 of the light emitting module is closed and the current I is input₂The second light emitting group is made to emit light, i.e. the parallel OLED

light emitting devices

1101 and 1102 emit light simultaneously, and since the light emitting areas and the device structures of the two devices are identical, the current flowing through each light emitting device is the same and is half of the total current, i.e. I₂/2, the current densities of the two devices are also J₂＝I₂V (2A), Total Voltage is OLED device at J₂Voltage V at current density₂All the brightness are L₂Having a first luminescent color coordinate C on the 1976CIE color coordinate diagram₂＝(u₂，v₂) Total luminous flux of the second light-emitting group phi₂Proportional to the product of luminance and area, Φ 2 ═ 2 π L₂2A. Let I₁＝I₂Then J is₂＝J₁/2<J₁，V₂<V₁The luminances of light emitting

devices

1101 and 1102 are approximately L₂＝L₁/2<L₁(generally, luminance is proportional to current density). At this time, since the color tunable OLED device operates at a lower current density, the recombination region is shifted, and the color C₂(u₂，v₂) Will be different from C₁(u₁，v₁) The difference duv calculated from the color coordinates of the two under the 1976 chromatogram may be greater than 0.01, more preferably greater than 0.05 and 0.1. At this time, although the luminance of the single device is reduced to half of that in the first operating state, the total luminous flux Φ is doubled due to the double total area₂＝2πL₂*2A＝ 2πL₁/2*2A＝Φ₁I.e. the total luminous flux remains unchanged. In a parallel circuit, assuming that the luminance of the OLED device in the module is approximately proportional to the current density, L ≈ kJ, i.e. I as long as the total input current remains unchanged₁＝I₂Can make it satisfy phi₁≈Φ₂And is independent of the total area of the light emitting groups. This is because it is assumed that the light emitting area of the first light emitting group in the first operating state is a₁The light emitting area of the second light emitting group in the second working state is A₂Total luminous flux phi of the first light-emitting group in the first operating state₁＝2πL₁*A₁≈2πkJ₁*A₁＝2πk*I₁Total luminous flux phi of the second light-emitting group in the second working state₂＝2πL₂*A₂≈2πkJ₂*A₂＝2πk*I₂As long as I₁＝I₂I.e. having phi₁≈Φ₂. But to make C₁≠C₂Must have J₁≠J₂I.e. I₁/A₁≠I₂/A₂. It can be seen that if the total current I is input₁＝I₂Then only satisfy A₁≠A₂Can the two light-emitting groups emit light with different colors, and then phi₁≈Φ₂. If the total current I is input₁≠I₂Then A is₁、A₂May or may not be equal but must satisfy I₁/A₁≠I₂/A₂So that the two light emitting groups emit light of different colors. However, regardless of the area of the two light emitting groups, since the two devices are connected in parallel, the voltage of the single device is equal, the current density is necessarily equal, and the two

parallel devices

1101 and 1102 in the same operating state have the same color. Note, however, that the same device color in the first and second operating states at this time is different, e.g., the color emitted by device 1101 in fig. 1a is different than the color emitted by device 1101 in fig. 1 b. In FIGS. 1a and 1b, the first light-emitting group contains only color tunable OLED light-emitting device 1101, and the second light-emitting group contains both light-emitting

devices

1101 and 1102, where A is necessarily the same₁≠A₂With constant input total current, two different colors C are possible₁And C₂. In other examples, the first light emitting group may only include the color tunable OLED light emitting device 1101, the second light emitting group may only include the light emitting device 1102, and if the total current input in the two operation states is not changed, the light emitting areas of the

light emitting devices

1101 and 1102 must be unequal to change the color, and if the total current input in the two operation states is not changed, the light emitting areas of the

light emitting devices

1101 and 1102 may be equal or unequal, but I must be satisfied₁/A₁≠I₂/A₂. Example 1 may be generalized to the parallel connection of more color tunable OLED devices, and the first and/or second OLED light emitting groups may each comprise a combination of devices, which may or may not have equal light emitting areas to each other. Example 1 may further comprise a third or even further light emitting group, which may be combined by further color tunable OLED devices, or by continuously varying the magnitude of the input current.

Example 2

The color tunable OLED lighting module comprises at least two color tunable

OLED lighting devices

1201 and 1202 and two

control switches

1203 and 1204, and fig. 4a and 4b show a circuit schematic diagram of the lighting module, wherein the

OLED lighting devices

1201 and 1202 are connected in series. The light emitting areas of the two devices are the same and assumed to be a, and the two light emitting devices have the same device structure. In example 2, the first light emitting group includes only the OLED light emitting device 1201, and the second light emitting group includes only the OLED light emitting device 1201The light emitting group includes OLED

light emitting devices

1201 and 1202. In the first operating state (fig. 4a), the control switch 1203 of the light emitting module is turned on, the control switch 1204 is turned off, and the input current I is applied₁To operate the first light emitting group, i.e. to emit light from OLED device 1201, the current through device 1201 is I₁Current density through OLED device 1201 is J₁＝I₁At this time, the luminance emitted by the OLED device 1201 is L₁Having a first color coordinate (u) on the 1976CIE color coordinate diagram₁，v₁) Total luminous flux phi₁Proportional to the product phi of brightness and area₁＝2πL₁A. In the second working state (fig. 4b), the

control switches

1203 and 1204 of the light emitting module are both in the open state, inputting the current I₂The second group of light emitting groups is operated, i.e. OLED

light emitting devices

1201 and 1202 emit light simultaneously, where the current densities through

OLED devices

1201 and 1202 are both J, equal₂＝I₂A, the light-emitting brightness is L₂Having the same second color coordinate (u) on the 1976CIE color coordinate diagram₂，v₂) Total luminous flux phi₂Proportional to the product phi of brightness and area₂＝2πL₂(2A). It can be seen that for OLED device 1201 at this point, the first color coordinate (u) is used₁， v₁) And a second color coordinate (u)₂，v₂) In contrast, J must be present₁≠J₂I.e. the total input current I in two operating states₁≠I₂. Total luminous flux phi₁And phi₂Only at I₁＝2I₂Will be equal under the premise of (1), and will not be equal under the other conditions.

Generalizing to the mode of fig. 4c on the basis of example 2, where the area of the second color-variable OLED device 1202 is different from 1201, the

devices

1201 and 1202 will also emit different colors in the second operating state due to the series configuration. Also, the total luminous flux Φ₁And phi₂Only at I₁＝2I₂Will be equal under the premise of (1), and will not be equal under the other conditions. Further generalizing to the mode of fig. 4d, the first operating state only includes the first color-tunable OLED device 1201, and the control switch 1203 is turned off and controlled in the second operating stateIf the switch 1204 is turned on, i.e. only the second color-tunable OLED device 1202 is operated and the area of the second color-tunable OLED device 1202 is different from 1201, then only I needs to be satisfied₁/A₁≠I₂/A₂That is, the two light emitting groups can be made to emit light of different colors, and the first luminous flux and the second luminous flux are different.

Example 2 can also be generalized to a series of more color tunable OLED devices, and the first and/or second OLED light emitting groups can each comprise a combination of devices, which may or may not have equal light emitting areas. Example 2 may further comprise a third or even further light emitting group, which may be combined by further color tunable OLED devices, or by continuously varying the magnitude of the input current.

In examples 1 and 2, when the external electric drive supplies the first current only to the first light emitting group or the second current only to the second light emitting group, it is considered that the first light emitting group and the second light emitting group are alternately operated.

Example 3

The color tunable OLED lighting module includes color tunable OLED

light emitting devices

1301, 1302, 1303 and 1304, and fig. 5a shows a circuit diagram of the combination. The

light emitting devices

1301, 1302, 1303 and 1304 have the same structure, and the same light emitting areas are all set as a. Each OLED device is connected with a resistor in series and then connected with other devices in parallel, and the resistance value of each resistor is equal to R. In example 3, the first light emission group contained only OLED light emitting device 1301, the second light emission group contained only OLED light emitting device 1302, the third light emission group contained only OLED light emitting device 1303, and the fourth light emission group contained only OLED light emitting device 1304. When the LED lamp works, the total current I is input, and the current flowing through the first light-emitting group is I₁The current flowing through the second light emitting group is I₂The current flowing through the third light emitting group is I₃The current flowing through the fourth light emitting group is I₄Due to the presence of a resistor, I₄<I₃<I₂<I₁Current density through

OLED devices

1301, 1302, 1303 and 1304 follows J₄＝I₄/A<J₃＝I₃/A<J₂＝I₂/A<J₁＝I₁and/A. Because the current density is different, the color of each light-emitting group is different, and an OLED light-emitting module with gradually changing color is formed. FIG. 5b shows a light module comprising OLED light emitting devices and resistors with different areas, wherein the first light module only comprises OLED light emitting device 1401 with area A₁The second light emitting group comprises OLED light emitting devices 1402 only, and has an area A₂The third light emitting group comprises only OLED light emitting devices 1403 with area A₃Fourth light emitting group includes OLED light emitting devices 1404 only and has an area A₄And A is₄＞A₃＞A₂＞A₁. When the LED lamp works, the total current I is input, and the current flowing through the first light-emitting group is I₁The current flowing through the second light emitting group is I₂The current flowing through the third light emitting group is I₃The current flowing through the fourth light emitting group is I₄Due to the presence of a resistor, I₄<I₃<I₂<I₁Therefore I is₄/A₄<I₃/A₃<I₂/A₂<I₁/A₁I.e. J₄<J₃<J₂<J₁Therefore, the light emitting colors of the

OLED panels

1401, 1402, 1403, 1404 are different, and a light emitting module with gradually changing colors and gradually changing areas is formed, similar to the oil display mentioned above. In some examples, the light emitting area of the OLED light emitting device may also be gradually reduced, as shown in fig. 5c, and the light emitting areas of the OLED

light emitting devices

1501, 1502, 1503, and 1504 are gradually reduced. At this time, it is noted that I is satisfied₄/A₄≠I₃/A₃≠I₂/A₂≠I₁/A₁To ensure different current densities and thus different colors of different devices, which can be achieved by matching the light emitting area or adjusting the resistance to adjust the current. In other examples, the light emitting area of the OLED light emitting devices may also be changed periodically, as shown in fig. 5d, the light emitting areas of the OLED

light emitting devices

1601, 1603 are the same, and the light emitting areas of the OLED

light emitting devices

1602, 1604 are the same and larger than the light emitting areas of the OLED

light emitting devices

1601, 1603. Note that this time must also be satisfiedI₄/A₄≠I₃/A₃≠I_2/A₂≠I₁/A₁. The resistors in series with the OLED light emitting device may also have different resistances, as shown in FIG. 5e for the case of increasingly smaller resistances, R₁>R₂>R₃Or the resistance becomes larger and larger as shown in FIG. 5f, R₁<R₂<R₃. Example 3 can also be generalized to a series of more color tunable OLED devices, and each OLED light emitting group can include a combination of multiple devices, which may or may not have equal light emitting areas.

The introduction of resistance in example 3 can be achieved by using the resistance of the cathode and anode layers of the OLED device itself. For example, the anode layer material of the commonly used OLED bottom emission device is ITO (indium tin oxide)

The resistivity at thickness is usually 15-20. omega./□, one 1cm by 1cm

The ITO squares have a resistance of 15-20 omega. Similarly, the cathode layer material of the OLED top-emitting device is typically MgAg in a ratio of 1: 9 in the doping ratio of

The resistivity at thickness is usually 10-15. omega./□, one 1cm by 1cm

According to the following steps: the MgAg square mixed with the doping ratio of 9 has the resistance of 10-15 omega. The process for introducing the resistance by using the cathode and anode electrode layers of the OLED device is simple and controllable, the resistance value can be defined by using the graph and the film thickness, and the preparation can be carried out synchronously with the preparation of the cathode and anode electrode layers of the device. In fact, the impedance introduced by the electrodes is already present in some large-area OLED light-emitting panels, as in the model described in patent US8,927,308. On the other hand, additional metal wiring can be introduced at the panel level as a resistor, even at the panel levelThe module end is introduced with a resistance element. In summary, the introduction of resistors into OLED modules is well known to those skilled in the art and is not within the scope of the present invention.

Example 4

The color tunable OLED lighting module comprises 4 series connected color tunable

OLED lighting devices

1701, 1702, 1703 and 1704, as shown in fig. 6a, the 4 OLED devices having the same device structure. In example 4, the first light emitting group includes only the OLED light emitting device 1701 and has an area B₁The second light emitting group includes OLED light emitting devices 1702 only, with area B₂The third light emitting group comprises OLED light emitting devices 1703 only, and has an area B₃Fourth light emitting group includes OLED light emitting devices 1704 only, and has area B₄The light emitting areas of the 4 OLED light emitting devices are gradually reduced, namely B₄<B₃<B₂<B₁. When the total current I is input during operation, the current flowing through the whole circuit is the same, but the current density flowing through different devices is different due to different light-emitting areas of each OLED device, and the current density passing through the device 1701 is J₁＝I/B₁The current density through the device 1702 is J₂＝I/B₂Current density through device 1703 is J₃＝I/B₃Current density through OLED device on device 1704 is J₄＝I/B₄Due to B₄<B₃<B₂<B₁Therefore J₄>J₃>J₂>J₁Therefore, the colors of the OLED light emitting devices 1701, 1702, 1703 and 1704 are also different, and a light emitting module with gradually changing colors and gradually changing areas can be formed, similar to the oil amount display mentioned above. In some examples, the light emitting areas of the OLED light emitting devices may also be sequentially increased, as shown in fig. 6b, the light emitting areas of the OLED

light emitting devices

1801, 1802, 1803, 1804 are gradually increased. In other examples, the OLED lighting module is formed by repeating at least two parallel OLED lighting devices connected in series, as shown in fig. 6c, the

OLED lighting devices

1911 and 1921, 1912 and 1922, 1913 and 1923, 1914 and 1924 are connected in parallel, and then the parallel devices are connected in series. Although OLED devices are shownThe areas of the devices are all the same, but this is merely an example and the areas of the individual devices may not be equal.

All light emitting groups in examples 3 and 4 were operated simultaneously.

In the following we prepared actual color tunable devices and combined to demonstrate the application of the invention.

Firstly, a white light OLED light-emitting device in the color-adjustable OLED light-emitting module is prepared, and the structure of the device is as follows: first, a glass substrate having a 1200 angstrom thick Indium Tin Oxide (ITO) anode layer 101 patterned in advance thereon was washed with ultrapure water, and the ITO surface was treated with UV ozone and oxygen plasma. The substrate was then dried in a nitrogen-filled glove box to remove moisture, mounted on a rack and loaded into an evaporation chamber. The organic layers specified below were evacuated to a vacuum of about 1 x 10^-7In the case of torr, the coating was sequentially performed on the ITO anode by thermal evaporation at a rate of 0.01-5 a/sec. Compound HI was first evaporated to a thickness of 100 angstroms to serve as a Hole Injection Layer (HIL). Compound HT was used as a Hole Transport Layer (HTL) with a thickness of 350 angstroms. The compound H-1 was used as an Electron Blocking Layer (EBL) with a thickness of 50 angstroms. Then, a blue dopant compound D-1 doped in a blue host compound H-2 is co-deposited as a blue light emitting layer (BEML) with a doping concentration of 4% and a total thickness of 100 angstroms. The compound H-3 is used as a regulating layer and is evaporated on the blue light emitting layer, and the thickness is 10 angstroms. And then, evaporating a green light emitting layer (GEML) on the adjusting layer, wherein the green light emitting layer is formed by co-evaporation of a compound H-3, a compound H-4 and a compound D-2, and the proportion of H-3, H-4 and D-2 is 46%: 46%: 8% and a total thickness of 50 angstroms. Next, a red dopant compound D-3 is doped in a red host compound H-5 to co-deposit as a red light emitting layer (REML) with a total thickness of 50 angstroms, wherein the dopant compound D-3 accounts for 2%. The compound H-3 was used as a Hole Blocking Layer (HBL) and was deposited on the red light emitting layer to a thickness of 50 angstroms. On the HBL, compound ET and compound EIL were co-deposited to 350 angstroms as an Electron Transport Layer (ETL), with compound EIL accounting for 60%, evaporated to a thickness of 10 angstroms as an Electron Injection Layer (EIL), and evaporated to 120 nm aluminum as a cathode, and finally the device was transferred from the evaporation chamber back to the glove box and used with aluminum as a cathodeAnd finishing encapsulation by the glass cover plate to form an encapsulation layer. The light emitting area of the single device is 9mm x 9mm, and the independent cathode and anode electric contacts can be driven independently. In this example, 72 identical independently controllable color tunable OLED devices can be fabricated on one substrate, which are individually packaged and cut into individual panels. Of course, these devices may also be encapsulated by a piece of encapsulating glass, or individually encapsulated but not cut, electrically driven by appropriate metal wiring or FPC leads. Note that this device structure is merely an example, and is not limited to the description of the present invention. The structures of compound HI, compound HT, compound H-1, compound H-2, compound H-3, compound H-4, compound H-5, compound D-1, compound D-2, compound D-3, compound ET, and compound EIL are shown below:

TABLE 1 device Performance of color tunable OLED light emitting devices at different operating points

We used a Keithley2400 power generator connected to the cathode and anode electrical contacts of the OLED device itself to be electrically driven externally. Table 1 lists the measured performance of the above individual color tunable OLED light emitting devices. From table 1, it can be seen that when the current density is gradually increased, the color coordinate CIEx of the device is changed from 0.495 to 0.267, the CIEy is changed from 0.418 to 0.274, and the color temperature is increased from 2337K to 13336K, which is a clear process of changing from warm white light to cold white light. The colors under different current densities are marked in a star shape in a CIE 1931 coordinate diagram of FIG. 7, and it can be seen that basically all the luminous points fall on a black body curve, which indicates that the white light is very standard white light, and the color rendering indexes are all larger than 89, which indicates that the color rendering indexes of the white light device prepared by the method can also meet the application of illumination. It can be seen that as the current density increases, the brightness also increases.

From the above device properties we make the following combination:

1. the first light-emitting group only comprises one OLED light-emitting panel with the light-emitting area of 0.81cm²The current density applied by the Keithley2400 power generator was 34.63mA/cm²When the luminance is 4600cd/m²The total luminous flux emitted by the OLED light-emitting module is 4600 multiplied by 0.081 multiplied by 10^-4X 2 pi is 2.34lm, 1931CIE color coordinates are (0.300,0.303), 1976CIE color coordinates are (u, v) ═ 0.199,0.451, and color temperature is 7710K.

2. The second light-emitting group comprises two OLED light-emitting panels with the same area and connected in parallel, and the total area is 2 x 0.81cm². 13.97mA/cm were also applied by a Keithley2400 power generator²At a current density of (2), the luminance of each block is 2200 cd/m²At this time, the total luminous flux emitted by the OLED light emitting module is 2200 × 2 × 0.081 × 10^-4X 2 pi is 2.24lm, 1931CIE color coordinates are (0.339,0.335), 1976CIE color coordinates (u, v) are (0.214,0.476), and color temperature is 5185K. Application of 34.63mA/cm with first set of OLED light emitting panels²The current density of (a) is substantially the same, but the difference duv ═ sqrt ((0.214-0.199) between the two colors²+(0.476-0.451)²)＝0.03>0.01, the color is obviously changed, so the light-emitting module realizes the purposes of different colors and color temperatures and basically consistent luminous flux. In fact, the current density can be adjusted to make the light flux of the two groups of OLED light-emitting panels consistent.

3. The light-emitting module comprises 9 OLED light-emitting devices with adjustable colors, the device structure is completely the same as that of the embodiment, and the light-emitting area of each OLED light-emitting device is the same and is 0.81cm². Two adjacent OLED devices are connected by using a layer of ITO with the thickness of 1200 angstroms and the size of 2mm multiplied by 16mm, and the resistance of the ITO connection is about 12 omega. The 9 OLED light emitting devices form a series structure, and the circuit principle thereof is as in the case of example 3. Similarly, a Keithley2400 power generator was used with the anode of the power generator in electrical contact with the anode of the first OLED device and the cathode of the power generator in electrical contact with the cathode of the last OLED in the series circuit, with a fixed electrical drive provided by the power generator. Can be used forIt is seen that the actual current split across each OLED device is different due to the ITO resistance, and thus the brightness and color have a significant trend of change.

It should be understood that the various embodiments described herein are illustrative only and are not intended to limit the scope of the invention. Thus, the invention as claimed may include variations from the specific embodiments and preferred embodiments described herein, as will be apparent to those skilled in the art. Many of the materials and structures described herein may be substituted with other materials and structures without departing from the spirit of the present invention. It should be understood that various theories as to why the invention works are not intended to be limiting.

Claims

1. The color-adjustable OLED light-emitting module is characterized by comprising an OLED light-emitting group and an external electric drive;

2. The color tunable OLED lighting module of claim 1 wherein the first and second current intensities are different, or wherein the first and second light emitting areas are different, or wherein the first and second current intensities, the first and second light emitting areas are both different.

3. The color tunable OLED lighting module of claim 2 wherein the first and second currents are of the same intensity and the first and second light emitting areas are different.

4. The color tunable OLED lighting module of claim 2 wherein the first and second currents are of different intensities and the first and second light emitting areas are different or the same.

5. The color tunable OLED lighting module according to claim 1 wherein the organic layers in the OLED lighting device have the same structure.

6. The color-tunable OLED lighting module according to claim 1 wherein the first and second intrinsic peak wavelengths differ by at least 50 nm.

7. The color-tunable OLED lighting module according to claim 1 wherein the first and second intrinsic peak wavelengths differ by at least 80 nm.

8. The color-tunable OLED lighting module according to claim 1 wherein the first and second intrinsic peak wavelengths differ by at least 100 nm.

9. The color-tunable OLED lighting module of claim 1 wherein the organic layer of the OLED light emitting device further comprises a third light emitting layer, wherein the third light emitting layer comprises a third intrinsic peak wavelength, and wherein the third intrinsic peak wavelength is different from both the first intrinsic peak wavelength and the second intrinsic peak wavelength by at least 30 nm.

10. The color-tunable OLED light module according to one of claims 1 or 9, wherein the organic layers of the OLED light device further comprise a tuning layer, wherein the tuning layer is disposed between adjacent light-emitting layers.

11. The color-tunable OLED lighting module according to claim 1 wherein at least one of said OLED lighting devices belongs to both the first lighting group and the second lighting group.

12. The color tunable OLED lighting module according to claim 1 wherein the first and second light emitting groups operate simultaneously or alternately.

13. The color tunable OLED lighting module of claim 1 wherein the first and second light emitting facets are either regularly shaped or irregularly shaped.

14. The color tunable OLED lighting module of claim 1 wherein at least two of said OLED lighting devices have the same or different light emitting areas.

15. The color tunable OLED lighting module of claim 1 wherein at least two of the OLED light emitting devices in the first light emitting group are connected in series or in parallel; wherein at least two OLED light emitting devices in the second light emitting group are connected in series or in parallel.

16. The color tunable OLED lighting module according to claim 1, wherein at least one OLED device in the first lighting group and at least one OLED device in the second lighting group are connected in series or in parallel.

17. The color tunable OLED lighting module of claim 1 wherein at least two of said OLED lighting devices are on the same substrate.

18. The color tunable OLED lighting module of claim 1 wherein the OLED light emitting devices are all on the same substrate.

19. The color-tunable OLED lighting module according to claim 1 wherein the first and second color coordinate points have a duv value greater than 0.05.

20. The color-tunable OLED lighting module according to claim 1, wherein the first color coordinate point and the second color coordinate point have a duv value greater than 0.1.

21. The color tunable OLED lighting module of claim 1 further comprising a resistive element.

22. The color tunable OLED lighting module according to claim 21 wherein the resistive element is made of one or a combination of anode layer material, cathode layer material, metal, transparent oxide, FPC lead material.

23. The color tunable OLED lighting module of claim 1 wherein the OLED light emitting device emits white light and the tunable range of color temperature at different current densities is 2000K-9000K.

24. A consumer product comprising a color-tunable OLED lighting module as claimed in any one of claims 1 to 23.