Hans U. Güdel Department für Chemie und Biochemie Seminar Fribourg, Making light

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3 Area illuminators

4 OLED Technology

5 Light White and coloured light Photoluminescence, phosphors Spectrum Light emitting diodes (LED) Outlook Making light Light

6 Making light

7 Fiat Lux 1in principio creavit Deus caelum et terram 2terra autem erat inanis et vacua et tenebrae super faciem abyssi et spiritus Dei ferebatur super aquas 3dixitque Deus fiat lux et facta est lux 4et vidit Deus lucem quod esset bona et divisit lucem ac tenebras First Book Moses (Genesis), Chapter 1

8 Black body radiation Temperature:Colour: 2500°C 5000°C 7500°C

9 Black body radiation Temperature:Colour: 5000°C

10 Human eye photoreceptors

11 Incandescent lamp 2500°C

12 Dispersion of white light

13 Making light: Additive mixing

14 Chromaticity Diagram

15 Photoluminescence

16 Kasha's Rule

17 Light emitting semiconductor Light emission Conduction band Valence band + – Bandgap

18 Photoluminescence of CdSe Nanoparticels

20 Fluorescent lamp

21 Luminescent phosphors

22 Lamp and display phophors BaMgAl 10 O 17 : Eu 2+ (Ce,Gd)MgB 5 O 10 : Tb 3+ Y 2 O 3 : Eu 3+ Judith Grimm

23 The Lanthanides

24 Coloured light

25 LED based technology

26 Light emitting diodes (LED) Electroluminescence Conduction band Valence band + – Bandgap

27 LED Materials Inorganic III – V Semiconductors Al, Ga, In N, P, As, Sb Al Ga As Al Ga In P Al Ga P Ga N Organic (OLED) Polymeric luminescent molecules with conjugated electron systems Polyphenylenvinylene n

28 Light emitting polymer

29 Mirco Colombo citations, 3 papers

30 Diode spectra

31 White diode lamp Y 3 Al 2 (AlO 4 ) 3 : Ce 3+ Diode + –

32 Chromaticity Diagram

33 Energy efficiency of light sources

34 Light sources Technology steps Electronics Tube analog TubeDiode Solid Micro electronics digital, solid

35 Area illuminators

36 Acknowledgment Gabriela Frei