由於利用小分子有機材料或高分子材料所製造的有機發光元件相當適合於平面顯示器的應用，所以近年來受到廣泛的研究。
在這本論文中，我們利用古典電磁學的理論來分析並模擬有機發光元件的發光特性。有機發光元件中的激子可以用一組不同振盪頻率的電偶極子來表示。利用將電偶極子產生的電磁場以平面波展開的方式，我們可以得到在有機發光元件中電磁場及功率分布的公式。由此進一步推導可以得到元件發光頻譜，發光效率，及元件發光特性隨角度的變化關係的公式。利用這些公式我們計算並分析了一般型有機發光元件，上方發射型有機發光元件，及微共振腔型有機發光元件的發光頻譜，發光效率，及元件發光特性隨角度的變化關係。從這些分析中可以看出，有機發光元件的發光特性對元件中各層的厚度相當敏感。所以要使元件的發光特性最佳化，各層的厚度要小心的控制。

Organic light emitting devices (OLEDs) based on small-molecule organic materials or polymer materials have been extensively studied because of their various properties suitable for flat panel display applications.
In this thesis, we use the classical electromagnetic theory to model and analyze the emitting properties of OLEDs. Excitons in OLEDs are represented by an ensemble of single-frequency electric dipoles. Using the plane-wave expansion of the dipole field, we derive the formulation for electromagnetic field and power distribution in OLED structures. Then the formulas for the modification of emission spectrum, device optical out-coupling efficiency, and angular dependence of emission properties are further derived and are used in analyzing typical OLEDs, top-emitting OLEDs , and microcavity OLEDs. We found that these emitting properties are sensitive to thicknesses of various layers in OLED structures. So layer thicknesses should be carefully controlled to optimize emission properties of OLEDs.

1 Introduction 6
2 Fundamental Theory 8
2.1 Physics of Organic Light-EmittingMolecules . . . . . . . . . . . . . . . . . . . . 8
2.2 Classical Dipole Field in an InfiniteMedium. . . . . . . . . . . . . . . . . . . . . 9
2.3 Classical Dipole Field in Layered Structure . . . . . . . . . . . . . . . . . . . . . 12
2.3.1 Plane-Wave Solution in Sourceless Layered Structure . . . . . . . . . . . . 12
2.3.2 Plane-Wave Solution of Dipole in Layered Structure . . . . . . . . . . . . 15
2.4 Power Flow of Dipole Field in Layered Structure . . . . . . . . . . . . . . . . . . 19
2.4.1 Poynting’s Theory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
2.4.2 Total Radiated Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
2.4.3 Far-Field Radiation Intensity . . . . . . . . . . . . . . . . . . . . . . . . . 24
3 Optical Model of OLED 29
3.1 Input Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
3.2 Modeling Light-Emitting Molecules by Classical Electric Dipoles . . . . . . . . . 31
3.2.1 Orientational Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
3.2.2 Spectral Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
3.3 Internal and External Luminescence Quantum Eciency . . . . . . . . . . . . . . 38
3.4 Optically Thick Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
3.5 Spatial Distribution of Excitons . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
4 Analysis and Design of Various OLED Structures 43
4.1 Determination of Optical Properties ofMaterials . . . . . . . . . . . . . . . . . . 43
4.1.1 Sample Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
4.1.2 Refractive Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
4.1.3 PL Spectrum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
4.1.4 PL QuantumYield . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
4.2 Typical OLED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
4.2.1 Power Distribution and Coupling Eciency . . . . . . . . . . . . . . . . . 46
4.2.2 Angle-Dependent EL Spectrumand Intensity . . . . . . . . . . . . . . . . 50
4.3 Top-Emitting OLED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
4.3.1 Power Distribution and Eciency . . . . . . . . . . . . . . . . . . . . . . 52
4.3.2 Angle-Dependent EL Spectrumand Intensity . . . . . . . . . . . . . . . . 52
4.4 Microcavity OLED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
4.4.1 Power Distribution and Eciency . . . . . . . . . . . . . . . . . . . . . . 54
4.4.2 Angle-Dependent EL Spectrumand Intensity . . . . . . . . . . . . . . . . 55
4.4.3 Influences of Intrinsic Emission Spectrum Bandwidth . . . . . . . . . . . 56
5 Summary and Future Works 90
5.1 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
5.2 FutureWork . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

1 C. W. Tang and S. A. VanSlyke, Appl. Phys. Lett. 51, 913(1987)
2 J. H. Burroughes, D. D. Bradley, A. R. Brown, R. N. Marks, K. Mackay, R. H. Friend, P. L. Burns, and A. B. Holmes, Nature(London) 347, 539(1990)
3 V. Bulovic, V. V. Khalfin, G. Gu, P. E. Burrows, D. Z. Garbuzov, and S. R. Forrest, Phys. Rev. B 58, 3730(1996)
4 H. Yokoyama, Science 256, 66(1992).
5 A. Sommerfeld, Ann. Phys. 28, 665(1909)
6 H. Kuhn, J. Chem. Phys. 53, 101(1970)
7 R. R. Chance, A. Prock, and R. Silbey, Adv. Chem. Phys. 37, 1(1978)
8 W. Lukosz, J. Opt. Soc. Am 67, 1607(1977)
9 J. E. Sipe, Surf. Sci. 105, 489(1981)
10 K. Neyts, Semiconductors and semimetals vol 65, p183
11 W. L. Barnes, J. Mod. Opt. 47, 725(2000)
12 E. F. Schubert, N. E. Hunt, M. Micovic, R. J. Malik, D. L. Sivco, A. Y. Cho, and G. J. Zydzik, Science 265, (1994)
13 D. Neher, A. Wolf, C. Buebeck, G. Wegner, Chem. Phys. Lett. 163, 163(1989)
14 M. R. Philpott, J. Chem. Phys. 62, 1812(1975)
15 M. S. Yeung, and T. K. Gustafson, Phys. Rev. A 54, 5227(1996)
16 J. D. Jackson, Classical Electrodynamics Second Edition (JOHN WILEY & SONS 1975), chapter 6
17 J. J. Sakurai, Modern Quantum Mechanics (Addison-Wesley 1994)
18 Jin Au Kong, Electromagnetic Wave Theory (JOHN WILEY & SONS)
19 O. H. Crawford, J. Chem. Phys 89, 6017(1988)
20 H. A. Macleod, Thin-Film Optical Filters (McGraw-Hill 1989)
21 K. Miyamoto, and E. Wolf, J. Opt. Soc. Am 52, 615(1962)
22 C. W. Tang, S. A. Vanslyke, and C. H. Chen, J. Appl. Phys. 65, 3610(1989)
23 J. Kim, P. K. H. Ho, N. C. Greenham, and R. H. Friend, J. Appl. Phys. 88, 1073(200)
24 T. Kawase, D. J. Pinner, R. H. Friend,and T. Shimoda, Syn. Met. 111-112, 583(2000)
059

\QIT{\QBI{}{15c}}M. A. Baldo, D. F. O'Brien, M. E. Thompson, and S. R. Forrest, Phys. Rev. B \QTR{bf}{60}, 14422(1999)
25 T. Sasaoka et al., SID 01 DIGEST, 384(2001)
26 L. S. Hung, C. W. Tang, M. G. Mason, P. Raychaudhuri, and J. Madathil, Appl. Phys. Lett. 78, 544(2001)
27 A. Dodabalapur, L. J. Rothberg, R. H. Jordan, T. M. Miller, R. E. Slusher, and J. M. Phillips, J. Appl. Phys. 80, 6954(1996)
28 K. Neyts, P. De Visschere, D. K. Fork, and G. B. Anderson, J. Opt. Soc. Am B 17, 114(2000)
29 S. E. Burns, N. Pfeffer, J. Gruner, D. Neher, and R. H. Friend, Syn. Met.84, 887(1997)
30 M. Berggren, O. Inganas, T. Granlund, S. Guo, Goran Gustafsson, and M. R. Andersson, Syn. Met. 76, 121(1996)
31 P. T. Worthing, J. A. E. Wasey, and W. L. Barnes, J. Appl. Phys. 89, 615(2001)
32 N. Takada, T. Tsutsui, and S. Saito, Appl. Phys. Lett. 63, 2032(1993)
33 J. C. de Mello, H. F. Wittmann, and R. H. Friend, Adv. Mater. 9, 230(1997)