Sökning: "Lysdioder"

Visar resultat 11 - 15 av 20 avhandlingar innehållade ordet Lysdioder.

1. 11. Carrier dynamics in blue and green InGaN LED structures

   Författare :Rinat Yapparov; Saulius Marcinkevičius; Ulrich Theodor Schwarz; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; InGaN quantum wells; interwell transport; near-field scanning optical microscopy; internal quantum efficiency; V-defects; InGaN-kvantbrunnar; transport mellan brunnar; optisk mikroskopi med närafältsskanning; intern kvanteffektivitet; V-defekter; Physics; Fysik; Optics and Photonics; Optik och fotonik;

   Sammanfattning : This thesis focuses on effects that are critical to achieving high internal quantum efficiency (IQE) in GaN-based light-emitting diodes (LEDs) that emit in a broad spectral range, from violet to green-yellow. These effects include interwell carrier transport in multiple quantum well (QW) structures, lateral transport in the QW plane, and radiative and nonradiative recombination. LÄS MER

3. 12. Fibre-Optic Displacement and Temperature Sensing Using Coupling Based Intensity Modulation and Polarisation Modulation Techniques

   Författare :Johan Jason; Hans-Erik Nilsson; Bertil Arvidsson; Werner Daum; Mittuniversitetet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; optical fibre sensor; displacement measurement; temperature measurement; fibre coupling; intensity modulation; birefringence; polarisation; OTDR; side-hole fibre;

   Sammanfattning : Optical fibre sensors are employed in the measurements of a number of different physical properties or for event detection in safety and security systems. In those environments which suffer from electromagnetic disturbance, in harsh environments where electronics cannot survive and in applications in favour of distributed detection, fibre-optic sensors have found natural areas of use. LÄS MER

4. 13. Dynamics in Blue Emitting Metal Halide Perovskites for Light Emitting Diodes

   Författare :Max Karlsson; Feng Gao; Tze Chien Sum; Barry P. Rand; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Perovskites; Light-emitting diodes; Stability; Efficiency;

   Sammanfattning : Lighting comprises a large part of the global electricity consumption as of today, and the use of lighting in illumination and displays is only projected to grow. It is therefore imperative to meet this energy demand, not only by means of greener energy production, but also with materials that are both more efficient to fabricate as well as to use. LÄS MER

5. 14. Interfaces in Organic Solar Cells

   Författare :Xian'e Li; Mats Fahlman; Xianjie Liu; Artem Bakulin; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : Organic semiconductors (OSs), the promising candidates for the next generation electronic devices, have shown their advantages of light weight, flexibility, semi-transparency, tunable optical gaps, and energy levels, in the development history of over 70 years. OSs have been widely used in versatile applications such as organic light-emitting diodes, organic field-effect transistors, organic photodetectors, and organic solar cells (OSCs) which are mainly studied in this thesis. LÄS MER

7. 15. Growth and Characterization of Ti-Si-N Thin Films

   Författare :Axel Flink; Lars Hultman; Paul Mayrhofer; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Analytical transmission electron microscopy; Arc; Sputtering; Hard coatings; Multilayer Cutting inserts; analytisk transmissionselektronmikroskopi; ytbeläggningar; skärande; bearbetning; Ti-Si-N; arcförångning; sputtring; Material physics with surface physics; Materialfysik med ytfysik;

   Sammanfattning : Utvecklingen inom materialforskningen går mot att framställa avancerade material vilka är skräddarsydda för olika tillämpningar. Detta har medfört att det blir allt mer populärt att belägga ytor med ett eller flera tunna lager med syfte att förbättra materialegenskaperna. LÄS MER