Background technology
(organic electroluminescence, OEL) display module is with multinomial characteristics such as frivolous, high parsing, power saving and the inorganic light-emitting diode active illuminating of LCD, high answer speeds for organic electroluminescent.Yet because the bottom surface of OLED display module is a metallic diaphragm traditionally, the contrast of panel can reduce significantly because of the reflection of external environment light when its display application, causes the image identification rate not good.
Known improvement method be on substrate applying one deck rotatory polarization sheet (circular polarizer, CP), the phase place that changes the extraneous light of incident is whereby eliminated reverberation.Of No. the 5th, 596,246, the U.S. and the 6th, 211, No. 613 patents, in the back side of display module applying rotatory polarization sheet, the method can be applicable to carry out volume production, can increase manufacturing cost relatively but increase the rotatory polarization sheet.In addition, also can adopt modes such as optical absorption and optical interference to reduce metal film reflectivity or enhancing contrast ratio.The U.S. the 6th, 185, No. 032, the 6th, 558, No. 820, the patent and the U.S. the 6th disclosed No. 2002/0043928 in early days, 545, another practice that is proposed in No. 409 promptly plated the thin dark color of one deck or the suction optical activity material of black before the reflective metal electrode of ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly, with reflectivity that reduces the component metals electrode and the contrast that improves panel.In addition, also can be as No. the 6th, 411,019, U.S. and the 6th, 545, No. 409 patents, and the method that institute discloses employing optical absorption cooperation destruction interference in U.S. the 6th, 429, No. 451, the 6th, 608, No. 333 reduces the reflectivity of assembly.The 6th, 411, the modular construction that No. 019 patent disclosed is to add an interfering layer in the ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly, and this interfering layer is interval between the electrode and luminescent layer of display module, utilizes optical absorption and destruction interference to reduce the reflectivity of assembly.In order to excite the organic electro luminescent layer that is interval between anode layer and the cathode layer, so the interfering layer that is provided with must be a conductive material, and the work function difference of interfering layer and metal electrode (workfunction difference) must be very little, Fang Buhui reduces the transmission of charge carrier, causes the increase of assembly operation voltage.Thereby reduced the selectivity of interfering layer material, and for meeting the requirement of conductivity and work function, the mixed layer of general selective oxidation indium tin, indium zinc oxide or aluminium and silica etc. are as interfering layer, and the selectivity of its interfering layer material limits higher.The U.S. the 6th, 545, No. 409 and the U.S. the 6th, 429, the modular construction that is disclosed in No. 451 patents is the structure of adopting thin cathodic metal/light absorbing zone/dielectric layer/metal level in the ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly, controls the condition of light absorbing zone and dielectric layer whereby, similarly utilizes optical absorption and destruction interference to reduce the reflectivity of assembly, but its thin cathode electrode and metal interlevel are for electrically conducting, so the selection space of its light absorbing zone and dielectric layer material is bigger.This technology needs plate light absorbing zone and dielectric layer two layers of material more, on making with condition control on relative to complexity.
Summary of the invention
Technical problem to be solved by this invention provides a kind of ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly, solves the existing extraneous catoptrical technical sophistication of ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly, the problem of poor selectivity eliminated.
For achieving the above object, the invention provides a kind of ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly, its characteristics are, include: an organic electro luminescent layer; One transparency electrode and a metal electrode, this transparency electrode and this metal electrode are located at the both sides of this organic electro luminescent layer respectively, emit beam to excite this organic electro luminescent layer; One key-course is adjacent to this metal electrode, is the light transmission key-course; One auxiliary electrode is adjacent to this key-course, is separated with this key-course between this auxiliary electrode and this metal electrode, reaches electric connection by a conducting district between this auxiliary electrode and this metal electrode.
Above-mentioned ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly, its characteristics be, this transparency electrode is made of wherein one or more of tin indium oxide, indium zinc oxide and thin metallic compound.
Above-mentioned ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly, its characteristics are that this metal electrode is selected from metal, alloy and metal oxide.
Above-mentioned ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly, its characteristics are that the thickness of this metal electrode is below 20 nanometers
Above-mentioned organic electric-excitation luminescent display module, its characteristics are that this key-course is selected from inorganic insulating material, inorganic semiconductor material, organic insulating material, organic semiconducting materials and combination thereof.Above-mentioned ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly, its characteristics are that the thickness of this key-course is below 300 nanometers.
Above-mentioned ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly, its characteristics are that this auxiliary electrode contains more than one metal.
Above-mentioned ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly, its characteristics are that the thickness of this auxiliary electrode is more than 30 nanometers.
Above-mentioned ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly, its characteristics are, also comprise a transparency carrier, and the upper surface of this transparency carrier forms this transparency electrode, this organic electro luminescent layer, this metal electrode, this key-course and this auxiliary electrode in regular turn.
Above-mentioned ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly, its characteristics are that the lower surface of this transparency carrier is coated with an anti-reflective film or fits and go up the transparency carrier that another sheet is coated with anti-reflective film.
Above-mentioned ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly, its characteristics are, also comprise a substrate, form this auxiliary electrode, this key-course, this metal electrode, this organic electro luminescent layer and this transparency electrode on this substrate in regular turn.
Above-mentioned ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly, its characteristics be, also comprises a black shielding layer and be arranged at this organic electro luminescent layer to zone that should the conducting district.
Technique effect of the present invention is:
ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly provided by the invention, by in assembly, adding the key-course of one deck suitable thickness and tool light transmission, to eliminate the extraneous reverberation of ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly, promote the contrast of ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly and panel, improve the contrast quality of ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly image.And by modular construction design, key-course itself need not be conducted electricity and needn't adjust work function between each adjoining course, and make that the selection space of key-course material is bigger.The tool antiradar reflectivity ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly of the present invention rotatory polarization sheet of need not fitting can be applicable to active display with passive-type and makes, and lowers external environment reflection of light amount, improves the contrast of display pannel.
Further describe specific embodiments of the invention below in conjunction with accompanying drawing.
Embodiment
The present invention can be applicable to down light emitting-type (bottom emission) or goes up the ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly of light emitting-type (top emission), only must change the order and the part-structure of its plated film.
Cooperate first embodiment to describe down the light emitting-type structure in detail, please refer to Fig. 1, it is the structural representation of first embodiment of the invention.The ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly is by transparency electrode 110, organic electro luminescent layer 120, metal electrode 130, key-course 140 and auxiliary electrode 150 are formed, transparency electrode 110 is formed at transparency carrier 100 surfaces, specific region in the transparency electrode top plates organic electro luminescent layer 120, on organic electro luminescent layer 120, form metal electrode 130 again, and on metal electrode, form key-course 140 and auxiliary electrode 150, make auxiliary electrode 150 and metal electrode 130 interval key-courses 140, and reach electric connection by conducting district 141 between auxiliary electrode 150 and the metal electrode 130.
Because a key-course is not had in the conducting district 141 that engages with auxiliary electrode 150 of metal electrode 130, so the regional reflex rate is higher, for reducing its local reflex, can the black shielding layer be set in the zone in the corresponding conducting of organic electro luminescent layer district, as shown in Figure 2, it is the structural representation of second embodiment of the invention.For forming transparency electrode 110 in transparency carrier 100 surfaces in regular turn, organic electro luminescent layer 120, metal electrode 130, key-course 140 and auxiliary electrode 150, specific region in transparency electrode 110 tops plates organic electro luminescent layer 120, on organic electro luminescent layer 120, form metal electrode 130 again, and on metal electrode 130, form key-course 140 and auxiliary electrode 150, make auxiliary electrode 150 and metal electrode 130 interval key-courses 140, and electrically connect by conducting district 141 between auxiliary electrode 150 and the metal electrode 130, and be the reflectivity that reduces conducting district 141, be provided with black shielding layer 160 in the zone in corresponding conducting district 141.
In addition, owing to also can producing reflection, the interface of the display surface of ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly and air increases reflectivity, and in order to reduce the reflectivity of ensemble average, can plate anti-reflective film (anti-reflection coating) in display surface, as shown in Figure 3, it is the structural representation of third embodiment of the invention, form transparency electrode 110 in a surface of transparency carrier 100 in regular turn, organic electro luminescent layer 120, metal electrode 130, key-course 140 and auxiliary electrode 150, specific region in transparency electrode 110 tops plates organic electro luminescent layer 120, on organic electro luminescent layer 120, form metal electrode 130 again, and on metal electrode 130, form key-course 140 and auxiliary electrode 150, make auxiliary electrode 150 and metal electrode 130 interval key-courses 140, and reach electric connection by conducting district 141 between auxiliary electrode 150 and the metal electrode 130. and another surface that is provided with black shielding layer 160. transparency carriers 100 except the zone in the corresponding conducting of organic electro luminescent layer district 141 is display surface, then be coated with anti-reflective film 170, further to effectively reduce the reflectivity of ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly.
Last light emitting-type structure please refer to Fig. 4, and it is the structural representation of fourth embodiment of the invention.The ORGANIC ELECTROLUMINESCENCE DISPLAYS assembly is made up of transparency electrode 210, organic electro luminescent layer 220, metal electrode 230, key-course 240 and auxiliary electrode 250.Auxiliary electrode 250 is formed at substrate surface, and forms key-course 240 on auxiliary electrode 250; On key-course 240, then form metal electrode 230, make auxiliary electrode 250 and metal electrode 230 interval key-courses 240, and electrically connect by conducting district 241 between auxiliary electrode 250 and the metal electrode 230.The specific region of metal electrode 230 tops then plates organic electro luminescent layer 220, forms transparency electrode 210 again on organic electro luminescent layer 220, and last emission type organic electro luminescent display module is as display surface with side with transparency electrode 210.
According to identical principle, last emission type organic electro luminescent display module also can form anti-reflective film at its display surface, reduces the reflection situation at the interface of display surface and air.Can the black shielding layer be set in the zone in corresponding conducting district equally, reduce the local reflex in the conducting district that metal electrode engages with auxiliary electrode.
In the embodiment of the invention, the material of transparency electrode is selected from tin indium oxide (ITO), indium zinc oxide transparent conductive materials such as (IZO) or thin metal compound layer etc.; Metal electrode presents translucent, and its material is selected from metal, alloy or metal oxide etc., and the thickness of metal electrode is below 20 nanometers (nanometer).Key-course is the tool translucent material, can select inorganic insulating material, inorganic semiconductor material, organic insulating material, organic semiconducting materials or its combination, and its thickness is below 300 nanometers.Auxiliary electrode then contains more than one metal material at least, and as aluminium, silver, gold, copper etc. or its alloy, and its thickness is more than 30 nanometers.Organic electro luminescent layer can comprise the different layers array of hole injection layer (hole injection layer), hole transport layer (hole transport layer), luminescent layer (emission layer), electron transfer layer (electron transport layer), electron injecting layer (electron injection layer) and charge carrier generation layer (carrier generation layer) and close.
Can eliminate the reflection that most extraneous light causes for proving assembly of the present invention, special key-course with unlike material cooperates the structure of first embodiment of the invention to test, the key-course material is respectively lithium fluoride (LiF), nitrogen, nitrogen '-two phenyl-nitrogen, nitrogen '-(the two naphthyls of 1-) benzidine (NPB) and glimmering alkene (rubrene), its thickness can be adjusted according to the optical property demand reaches different-effect.
First test case
Clean glass substrate with cleaning agent earlier, glass substrate has transparent transparency electrode, places the ultrasonic waves oscillator to clean again, uses the concussion of pure water and isopropyl alcohol ultrasonic waves afterwards more in regular turn, places baking oven dry at last.Glass substrate is put on the carrier, it is inserted is used for carrying out in the cavity of evaporation,, earlier oxonium ion is carried out on the surface and handle on glass substrate, to carry out the making of organic electro luminescent layer.Then in regular turn in the transparency electrode surface in regular turn the aluminum fluoride (AlF3) of evaporation 5 nanometers as the nitrogen of hole injection layer, 60 nanometers, nitrogen '-two phenyl-nitrogen, nitrogen '-(1-two naphthyls) benzidine as (three-(oxine) aluminium) of hole transport layer and 60 nanometers (Alq3) as luminescent layer and electron transfer layer, to form the electroluminescent organic material layer.And then on the evaporation aluminium of the lithium fluoride of 0.5 nanometer and thickness X 1 nanometer as metal electrode, and on metal electrode the lithium fluoride of evaporation thickness Y1 nanometer as key-course, at last, the aluminium that plates 100 nanometers again is as auxiliary electrode, and the conducting district of metal electrode and auxiliary electrode can adjust control by metallic shield and deposition angles.Assembly is carried out carrying out reflectivity with the assembly after the encapsulation and measuring after cover plate encapsulation finishes, and the test result of the assembly of its different X1 and Y1 as shown in Table 1.
Table one
Al=X1nm |
LiF=Y1nm |
Average reflectance (%) |
8 |
72 |
14.6 |
7.2 |
72 |
10.2 |
6.4 |
72 |
6.6 |
6.4 |
64 |
7.4 |
6.4 |
80 |
5.9 |
0 |
0 |
63.4 |
Learn that by The above results (average reflectance of scope of 400nm~700nm), (X1=0 be 63.4% Y1=0), and the reflectivity of the assembly gained in first test case is all far below 63.4% of standard package not contain the standard package of key-course at visible light.Standard package (the X1=0 of key-course will do not contained, Y1=0) measure to such an extent that average reflectance is 7.4% behind the applying last layer rotatory polarization sheet (CP), and (the X1=6.4 of the assembly in first test case, Y1=80) its average reflectance only 5.9%, and being lower than fits goes up the assembly of rotatory polarization sheet, and (X-axis is a wavelength to this three's reflectance spectrum figure among the figure as shown in Figure 5, Y-axis is a reflectivity, A represents standard package, and B represents standard package+CP, and C represents first test case).
In addition, efficient aspect, the standard package luminous efficiency that does not contain key-course are on fitting behind the rotatory polarization sheet, and it is original 45% that luminous efficiency is reduced to because of the rotatory polarization sheet absorbs, still at least can be modular more than 50% yet contain its luminous efficiency of assembly of key-course.Electrical aspect, its starting voltage of assembly (turn-on voltage) that contains key-course is identical with standard package all at 2.6 volts (V), and both are also very close for the characteristic of voltage-to-current.
Second test case
The controlled condition of its technology is all identical with first test case with materials used, only changes the material of its key-course, adopts nitrogen, nitrogen '-two phenyl-nitrogen, nitrogen '-and (the two naphthyls of 1-) benzidine is as key-course, and to set its thickness be Y2.Aluminum metal thickness with metal electrode is made as X2 simultaneously.The test result of the assembly of its different X2 and Y2 as shown in Table 2.
Table two
Al=X2nm |
NPB=Y2nm |
Average reflectance (%) |
12.5 |
150 |
33.8 |
12.5 |
130 |
26.7 |
12.5 |
110 |
17.6 |
12.5 |
90 |
16.3 |
Al=X2nm |
NPB=Y2nm |
Average reflectance (%) |
10 |
90 |
13.6 |
7.5 |
90 |
19.6 |
The 3rd test case
The controlled condition of its technology is all identical with first, second test case with materials used, only changes the material of its key-course, adopts glimmering alkene as key-course, and to set its thickness be Y3.Aluminum metal thickness with metal electrode is made as X3 simultaneously.The test result of the assembly of its different X3 and Y3 as shown in Table 3.
Table three
Al=X3nm |
Rubrene=Y3nm |
Average reflectance (%) |
10 |
100 |
18.7 |
10 |
85 |
10.7 |
10 |
70 |
9.1 |
8 |
90 |
8.9 |
8 |
80 |
9.5 |
8 |
70 |
11.1 |
In addition, in order further to reduce reflectivity, assembly (X3=8 in the 3rd test case, Y3=90) anti-reflective film (anti-reflection coating on the another side evaporation of substrate, AR coating) or fit to go up the transparency carrier that another sheet is coated with anti-reflective film, to eliminate the reflection of substrate and air interface, the average reflectance of this assembly can be from falling 8.9% to 5.8%, (X-axis is a wavelength to this two reflectance spectrum figure among the figure as shown in Figure 6, Y-axis is a reflectivity, the D representative does not contain anti-reflective film, and the E representative contains anti-reflective film).
By the test result of first to the 3rd test case as can be known, modulation control by metal electrode and key-course, and anti-reflective film on the evaporation, can effectively reduce reflectivity, the composition that also can adjust auxiliary electrode in addition reaches better effect as using other metal or alloy to wait.
In above-mentioned test case, the metal electrode plated film angle different with local engagement employing metal guard (metal mask) cooperation between the auxiliary electrode controlled and made.Yet also can use other processing procedure to finish as modes such as shielding (shadow mask), barrier rib (rib), collimator (collimator), dry ecthing, laser treatment.
The above is preferred embodiment of the present invention only, is not to be used for limiting practical range of the present invention; Every according to equivalence variation and modification that the present invention did, all contained by claim of the present invention.