TTHHÈÈSSEE En vue de l'obtention du DOCTORAT DE L’UNIVERSITÉ DE TOULOUSE Délivré par Université Toulouse 3 Paul Sabatier (UT3 Paul Sabatier) Discipline ou spécialité : Génie Electrique Présentée et soutenue par Yuan ZHANG Le jeudi 4 décembre 2014 Titre : A new flat dark discharge lamp for backlight applications based on electron– excited– phosphor luminescence JURY Jean-Marc Bauchire, Prof. Ray-Lee Lin, Prof. Christian Glaize, Prof. Yann Cressault, Maître des Conférences HdR. Ecole doctorale : ED GEET Unité de recherche : Laboratoire plasma et conversion d’énergie Directeur(s) de Thèse : Georges ZISSIS Rapporteurs : Jean-Marc Bauchire, Prof. Ray-Lee Lin, Prof. Acknowledgements Acknowledgements First of all, I would like to express my deepest gratitude to Professor Georges Zissis, my research supervisor, for his patient guidance, enthusiastic encouragement and useful critiques of this research work. He has deep insight into the lighting and light sources industry, and is quite sensitive to the new trends in the technology development. Every discussion with him will inspire me with many new ideas. He is always confident and optimistic in the face of difficulty. What I learn from him is not only about the knowledge but also the attitude to the future life. I would like to thank Dr. Sounil BHOSLE for his guide and help with the vacuum system and the glass work, and Dr. Spiros Kitsinelis for his advice and assistance on the experiment and my paper work. My grateful thanks are also extended to all the teachers and technicians in our group: such as Mr. David BUSO, Mr. Laurent CANALE, Mr. Pascal DUPUIS, Mr. Manuel LOPES, Mr. Marc TERNISIEN, Mr. Cédric RENAUD, Mr. Jean-Luc, Mr. Gérald LEDRU and etc, for their kind and patient suggestions, without which I could have not complete my thesis. My sincere appreciation goes to my dear colleagues: Lydie AREXIS BOISSON, Arezki TOUMI, Ikbal MARGHAD, Laure BARREYRE-PANDELE, Angel BARROSO, Sovannarith LENG, Alaa ALCHADDOUD, Feng TIAN, and Ahmad Nazri Dagang. Your warmheartedness and kindness support my daily life and study in France. I wish to appreciate the help provided by Prof. M.C. Liu and and his group from Energy and Environment Research Laboratories of Industrial Technology Research Institute in Taiwan, who participated this study with great cooperation. And I would like to acknowledge the generous help from Prof. Shanduan ZHANG and other faculties and friends in Fudan University too. I would also like to extend my thanks to all the members in laboratory Laplace and all my dear friends in France and China for their encouragement and support. It is indeed my pleasure to meet and cooperate with them. i Acknowledgements Finally, I wish to thank my parents for their support and encouragement throughout my study and life. ii Table of contents Table of contents Acknowledgements ................................................................................................ i Table of contents.................................................................................................. iii General introduction ............................................................................................ 1 CHAPTER I: ........................................................................................................ 3 Introduction- Electrical Light Sources .................................................................. 3 I.1 Incandescent Lamps .......................................................................................................... 3 I.2 Mechanism of Discharge Lamps ...................................................................................... 5 I.2.1 Brief history of the gas discharge research ................................................................ 5 I.2.2 Voltage- current characteristic curve of discharge lamp ........................................... 8 I.2.3 Discharge Lamps ..................................................................................................... 11 I.2.4. Mercury problem for discharge lamp ..................................................................... 12 I.2.5 Lighting Mechanism ................................................................................................ 12 I.3. Solid-state Lamps (SSL) ................................................................................................ 14 I.3.1 LED .......................................................................................................................... 14 I.3.1 OLED ....................................................................................................................... 26 I.4 The Work of This Thesis ................................................................................................ 33 I.5 Summary ......................................................................................................................... 34 References ............................................................................................................................ 36 CHAPTER II: ...................................................................................................... 41 Theoretical Analysis on the FDDL ...................................................................... 41 II.1 Introduction ................................................................................................................... 41 II.2 Speciality of the Flat Dark Discharge Lamp (FDDL) ................................................... 42 iii Table of contents II.2.1 Introduction to FDDL ............................................................................................. 42 II.2.2 Comparison with the similar applications .............................................................. 43 II.2.3 Characteristics of FDDL ......................................................................................... 45 II.3 Physics of discharge theory ........................................................................................... 50 II.3.1 Mean free path ........................................................................................................ 50 II.3.2 General diffusion .................................................................................................... 52 II.3.3 Townsend discharge theory .................................................................................... 54 II.4 Theoretical Analysis on the FDDL ................................................................................ 58 II.4.1 Ions and electrons current distribution with x position .......................................... 58 II.4.2 Analyses by mean free path of ionization and excitation collision ........................ 60 II.5 Conclusion ..................................................................................................................... 66 Reference .............................................................................................................................. 67 CHAPTER III: .................................................................................................... 69 Experiment Results on FDDL .............................................................................. 69 III.1 Introduction .................................................................................................................. 69 III.2 Measurement of Basic Quality ..................................................................................... 69 III.2.1 Phosphor response to the laser .............................................................................. 69 III.2.2 FDDL sample tests ................................................................................................ 72 III.3: Lamp Character at Different Pressures ....................................................................... 79 III.3.1 Experiment setup ................................................................................................... 80 III.3.2 Neon at 0.19 mbar and 0.20 mbar ......................................................................... 81 III.3.3 Neon at different pressure ..................................................................................... 86 III.3.4 Start voltage ........................................................................................................... 93 III.3.5 Voltage-Current plot analysis ................................................................................ 94 III.4 Commentary ............................................................................................................... 100 III.4.1 Stability ............................................................................................................... 100 III.4.2 Infrared camera analysis ...................................................................................... 103 iv Table of contents III.4.3 Scanning electron microscope (SEM) analysis ................................................... 104 III.5 Conclusion .................................................................................................................. 107 Reference ............................................................................................................................ 108 General conclusions .......................................................................................... 111 v Table of contents vi General introduction General introduction Since the first practical incandescent lamp was manufactured by Edison, electrical light sources have been