EP1236216A1 - Diode electroluminescente organique a motifs de forme spherique - Google Patents

Diode electroluminescente organique a motifs de forme spherique

Info

Publication number
EP1236216A1
EP1236216A1 EP00974009A EP00974009A EP1236216A1 EP 1236216 A1 EP1236216 A1 EP 1236216A1 EP 00974009 A EP00974009 A EP 00974009A EP 00974009 A EP00974009 A EP 00974009A EP 1236216 A1 EP1236216 A1 EP 1236216A1
Authority
EP
European Patent Office
Prior art keywords
substrate
light emitting
planar form
planar
emitting device
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP00974009A
Other languages
German (de)
English (en)
Inventor
James C. Sturm
Conor F. Madigan
Min-Hao M. Lu
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Princeton University
Original Assignee
Princeton University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Princeton University filed Critical Princeton University
Publication of EP1236216A1 publication Critical patent/EP1236216A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K59/00—Integrated devices, or assemblies of multiple devices, comprising at least one organic light-emitting element covered by group H10K50/00
    • H10K59/80—Constructional details
    • H10K59/875—Arrangements for extracting light from the devices
    • H10K59/879—Arrangements for extracting light from the devices comprising refractive means, e.g. lenses
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B33/00—Electroluminescent light sources
    • H05B33/12—Light sources with substantially two-dimensional radiating surfaces
    • H05B33/22—Light sources with substantially two-dimensional radiating surfaces characterised by the chemical or physical composition or the arrangement of auxiliary dielectric or reflective layers

Definitions

  • This invention relates to the field of light emitting devices, and more particularly to organic light emitting devices (OLEDs) and the emission efficiency thereof.
  • ITO Indium Tin Oxide
  • a reflecting cathode e.g. Mg.Ag or Li.Al
  • an object of the invention to provide an increase in coupling efficiency for OLEDs.
  • an approach is provided for increasing the emission intensity of an organic light emitting diode (OLED) and the total external emission efficiency for an OLED at a normal viewing angle.
  • OLED organic light emitting diode
  • the inventive approach captures light previously lost to wave-guiding in the substrate and, with proper choice of substrate, light previously lost to wave- guiding in the organic/anode layers.
  • a surface texturing approach is provided which, when compared with devices fabricated on typical planar glass substrates, can at least double the emission efficiency for an OLED when glass substrates are used, and at least triple the OLED emission efficiency when high index plastic substrates are used.
  • Figure 1 shows ray diagrams for various light paths in a planar OLED.
  • Figures 2(a) and 2(b) provide a schematic depiction of the use of spherical surface features to improve light emission efficiency for an OLED according to the invention.
  • Figure 3(a) shows measured far field intensity distribution pattern for planar glass substrate and expected profiles of a Lambertian emitter.
  • Figure 3(b) shows experimental results for glass substrate devices with and without spherical surface features applied according to the invention.
  • Figure 3(c) shows experimental results for PC substrate devices with and without spherical surface features applied according to the invention, along with the planar glass substrate results.
  • the coupling efficiency ( ⁇ ext ) of an OLED is a critical factor in the determination of emission efficiency for an OLED display. It is straightforward to analyze ⁇ exl for the type of layered structure used in an OLED by considering the indices of refraction associated with each layer. As a predicate to that analysis, consider the ray diagram for planar OLEDs shown in Figure 1, demonstrating loss by light trapping in the substrate layer (ray II) and in the organic/anode layers (ray III). As shown by ray I of the figure, only light emitted at sufficiently small angles will escape.
  • ⁇ org . C2 a critical angle, ⁇ org . C2 , can be obtained, defined by s_n '1 (n subs /n or g). for which light emitted in the organic layer at an angle greater than ⁇ or g. c2 is wave-guided within the ITO and organic layers. This light emission path is illustrated as ray III in Figure 1.
  • ⁇ or g, ci defined by for which light emitted in the organic layer at an angle greater than ⁇ org, cl is wave-guided in the substrate — illustrated as ray II in Figure 1. Since only the light emitting at angles less ⁇ org , C2 is emitted from the device — illustrated as ray I in Figure 1. all of the remaining wave-guided light is effectively lost, representing a reduction in ⁇ ext .
  • Equation (1) For the expected range of the index of refraction for the organic layer ⁇ between 1.6 and 1.8, it can be seen from Equation (1), that the corresponding range for the coupling efficiency, ⁇ exl , will be between 0.20 and 0.15, demonstrating the significance of the coupling efficiency in degrading system efficiency — i.e. between 80 and 85 percent of the internally generated light is trapped within the device.
  • the external coupling efficiency has been improved by a factor of 1.9 ⁇ 0.2 by etching grooves in the glass around the OLED to redirect light trapped in the substrate and organic/ITO layers [See, G. Gu.
  • the attachment of a sphere to the backside of the substrate, or shaping the substrate into such a spherical form, shown in Figure 2(a) permits the light rays to escape the substrate at much greater angles.
  • n SUb S substrate index
  • I subs ( ⁇ subs ) is of interest because Equation (3) only describes the external intensity distribution when the substrate is planar. If the substrate forms a hemisphere with the device at its center, for instance, I e ⁇ t ( ⁇ ff) will be equal to I Subs ( ⁇ SUbs )- In fact, I subs ( ⁇ subs) plays a direct role in determining I ex t( ⁇ ff) in all cases except the special case of a planar substrate. Continuing, the effect of n subs on I subS is to focus the distribution as n SU bs is increased, until at which point I su bs( ⁇ S ubs) reproduces the isotropic intensity distribution initially generated in the organic layer.
  • the third and final of the derived parameters is the vertical offset of the device from the center of curvature of the lens (d 0ffset ).
  • This parameter is of interest because it strongly affects the far field distribution pattern.
  • the analytical expression for I ext when d 0 r se t ⁇ 0 can readily be found in the art. For purposes of this discussion, it is sufficient to point out that when the OLED is positioned too far from the lens (d 0 ff set > 0), I ext will be more focused than I SUbs. and when the OLED is positioned too closely to the lens (d 0ffSet ⁇ 0). I ext will less focused than I subs - However, over a wide range of offset values, there is only a minor degrading effect on ⁇ ex , due to
  • the inventors have implemented the approach of the invention for a number of embodiments, which are further described hereafter.
  • the OLEDs that constitute these various embodiments were fabricated on glass and polycarbonate (PC) substrates.
  • the glass substrate consisted of 0.7 mm and 1.1 mm-thick soda lime glass purchased from Applied Films Co. coated with ITO by the manufacturer.
  • the PC substrates consisted of 175 ⁇ m-thick sheets purchased from Goodfellows Co.. with a 100 nm ITO film deposited on it in an Edwards A306 RF magnetron sputter with 2 mTorr pure Ar gas at 150 W RF power at room temperature.
  • the sputter target was 90% In 2 ⁇ 3 -10% SnO, 3 in. in diameter.
  • the deposition rate was 33 nm/min.
  • the OLEDs were made by spinning on a single poly-(N-vinylcarbazole) (PVK)/2-(4-biphenyl)-5-(4-tert-butylphenyl)- l,3,4-oxadiazole(PBD)/Coumarin 6 (C6) layer, and evaporating a 100 to 200 nm Mg:Ag cathode [Wu].
  • Typical device size and geometry consisted of a circle 1.75 mm in diameter.
  • Trials 1 through 6 were performed with six different substrate structures, which are designated Trials 1 through 6 in Table 1.
  • a diagram of the substrate setup (with all relevant parameters identified) is provided in Figure 2(a).
  • I n ⁇ _ .a. /Io and F F 0 represent the ratio of normal emission intensity and total emission intensity respectively to the results obtained for identical devices fabricated on planar substrates of the same substrate material.
  • the total emission intensity measurement does not include edge emission.
  • Equation (1) predicts that the planar cases for the PC and glass substrates should be identical, it can be observed in Figure 3 c that the two cases (Trials 1 and 5) are indeed effectively identical within experimental uncertainties of the trials. This provides experimental justification for comparing the results obtained for PC substrates with those for glass substrates.

Abstract

L'invention concerne un dispositif électroluminescent comprenant un substrat transparent présentant une première surface et une seconde surface, une couche conductrice transparente sur la première surface, une couche organique disposée sur la couche conductrice transparente, une couche organique disposée sur la couche conductrice transparente ainsi qu'un contact supérieur disposé sur la couche organique, le contour de la seconde surface du substrat ayant une forme non plane.
EP00974009A 1999-10-29 2000-10-30 Diode electroluminescente organique a motifs de forme spherique Withdrawn EP1236216A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US16255299P 1999-10-29 1999-10-29
US162552P 1999-10-29
PCT/US2000/029822 WO2001033598A1 (fr) 1999-10-29 2000-10-30 Diode electroluminescente organique a motifs de forme spherique

Publications (1)

Publication Number Publication Date
EP1236216A1 true EP1236216A1 (fr) 2002-09-04

Family

ID=22586119

Family Applications (1)

Application Number Title Priority Date Filing Date
EP00974009A Withdrawn EP1236216A1 (fr) 1999-10-29 2000-10-30 Diode electroluminescente organique a motifs de forme spherique

Country Status (6)

Country Link
EP (1) EP1236216A1 (fr)
JP (1) JP2003513423A (fr)
KR (1) KR20020065893A (fr)
CN (1) CN1384970A (fr)
AU (1) AU1244601A (fr)
WO (1) WO2001033598A1 (fr)

Families Citing this family (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6939499B2 (en) 2001-05-31 2005-09-06 3M Innovative Properties Company Processes and apparatus for making transversely drawn films with substantially uniaxial character
US7053547B2 (en) 2001-11-29 2006-05-30 Universal Display Corporation Increased emission efficiency in organic light-emitting devices on high-index substrates
US7012363B2 (en) 2002-01-10 2006-03-14 Universal Display Corporation OLEDs having increased external electroluminescence quantum efficiencies
FR2836584B1 (fr) * 2002-02-27 2004-05-28 Thomson Licensing Sa Panneau electroluminescent dote d'elements d'extractions de lumiere
TWI341927B (en) * 2002-05-15 2011-05-11 Reflexite Corp Optical structures
US7153122B2 (en) 2002-05-28 2006-12-26 3M Innovative Properties Company Apparatus for making transversely drawn films with substantially uniaxial character
JP2004363049A (ja) * 2003-06-06 2004-12-24 Seiko Epson Corp 有機エレクトロルミネッセンス表示装置の製造方法及び、有機エレクトロルミネッセンス表示装置並びに、有機エレクトロルミネッセンス表示装置を備える表示装置
JP2005175417A (ja) * 2003-07-28 2005-06-30 Ricoh Co Ltd 発光素子アレイ、光書込ユニットおよび画像形成装置
WO2005025276A1 (fr) 2003-09-08 2005-03-17 Lg Chem, Ltd. Dispositif photoemissif organique hautement efficace utilisant un substrat dote d'evidements hemispheriques a echelle nanometrique et son procede de preparation
KR100977964B1 (ko) 2004-02-04 2010-08-24 사천홍시현시기건유한공사 유기 전계 발광소자
GB0404698D0 (en) * 2004-03-03 2004-04-07 Cambridge Display Tech Ltd Organic light emitting diode comprising microlens
US7414263B2 (en) 2004-03-16 2008-08-19 Lg Chem, Ltd. Highly efficient organic light-emitting device using substrate or electrode having nanosized half-spherical convex and method for preparing the same
US20060226561A1 (en) 2005-04-08 2006-10-12 3M Innovative Properties Company Heat setting optical films
US7798678B2 (en) 2005-12-30 2010-09-21 3M Innovative Properties Company LED with compound encapsulant lens
JP4839867B2 (ja) * 2006-02-03 2011-12-21 株式会社日立製作所 発光素子及び表示装置
KR101376558B1 (ko) * 2006-06-14 2014-03-21 코닌클리케 필립스 엔.브이. 조명장치
WO2009009695A1 (fr) 2007-07-10 2009-01-15 University Of Florida Research Foundation, Inc. Dispositifs électroluminescents organiques à émission vers le haut avec réseaux de microlentille
GB2457691A (en) 2008-02-21 2009-08-26 Sharp Kk Display with regions simultaneously operable in different viewing modes
US20100327304A1 (en) * 2009-06-30 2010-12-30 Shinichiro Sonoda Organic el device and design method thereof
JP5480567B2 (ja) * 2009-09-01 2014-04-23 パナソニック株式会社 有機発光素子
JP5306949B2 (ja) * 2009-09-14 2013-10-02 ユー・ディー・シー アイルランド リミテッド 有機電界発光装置
TW201122357A (en) * 2009-12-31 2011-07-01 Yuieh Hsene Electronics Co Ltd Light emission device using light transmissive layer as corresponding structure of refraction.
DE112011103543T5 (de) 2010-10-22 2013-08-01 Semiconductor Energy Laboratory Co., Ltd. Lichtemittierendes Element, lichtemittierende Vorrichtung und Beleuchtungsvorrichtung
US9293734B2 (en) * 2010-12-23 2016-03-22 Universal Display Corporation Light extraction block with curved surface
DE102014214721A1 (de) * 2014-07-25 2016-01-28 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Anordnung zur orts- und wellenlängenaufgelösten Erfassung von Lichtstrahlung, die von mindestens einer OLED oder LED emittiert wird
US10663745B2 (en) 2016-06-09 2020-05-26 3M Innovative Properties Company Optical system

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB9207524D0 (en) * 1992-04-07 1992-05-20 Smiths Industries Plc Radiation-emitting devices
EP0597391B1 (fr) * 1992-11-09 1998-09-09 Central Glass Company, Limited Plaque de verre avec un revêtement multicouche absorbant les rayonnements ultraviolets
JP3420399B2 (ja) * 1995-07-28 2003-06-23 キヤノン株式会社 発光素子
US5814416A (en) * 1996-04-10 1998-09-29 Lucent Technologies, Inc. Wavelength compensation for resonant cavity electroluminescent devices

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO0133598A1 *

Also Published As

Publication number Publication date
WO2001033598A1 (fr) 2001-05-10
JP2003513423A (ja) 2003-04-08
WO2001033598A8 (fr) 2001-11-01
CN1384970A (zh) 2002-12-11
AU1244601A (en) 2001-05-14
KR20020065893A (ko) 2002-08-14

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