Diffraction Grating Spectrometer Design and Collected Spectra Theremino System Theremino System – Spettrometro_ENG – Page 1 Table of contents Design and Components .................................................................................................................................... 6 Theory of Diffraction Grating ........................................................................................................................ 6 Diffraction Grating Specifications .................................................................................................................. 8 Portable Spectrometer Construction ................................................................................................................ 9 Benchtop Spectrometer Construction............................................................................................................. 10 Spectra of Lamps ............................................................................................................................................. 11 Spectral Lamps................................................................................................................................................. 14 Hydrogen ..................................................................................................................................................... 14 Carbon Dioxide ............................................................................................................................................ 15 Nitrogen ....................................................................................................................................................... 15 Spectra of Flames and Plasma ......................................................................................................................... 16 Emission and Atomic Absorption spectra ........................................................................................................ 17 LED Spectra ...................................................................................................................................................... 18 Laser Spectra ................................................................................................................................................... 20 Sun Spectrum .................................................................................................................................................. 22 Wien Law / Black body radiation ................................................................................................................. 24 Comparison with Reference Spectra ............................................................................................................... 25 CFL Lamp ...................................................................................................................................................... 25 Neon Lamp .................................................................................................................................................. 26 Sodium-vapor Lamp..................................................................................................................................... 27 Absorption Spectroscopy ................................................................................................................................ 28 Absorption Spectrometer Design ................................................................................................................ 28 Water ........................................................................................................................................................... 29 Red Wine ..................................................................................................................................................... 29 Blue Food Dye .............................................................................................................................................. 30 Yellow Food Dye .......................................................................................................................................... 30 Blue Ink ........................................................................................................................................................ 30 Fluorescence Spectroscopy ............................................................................................................................. 31 Fluorescence Spectrometer Design ............................................................................................................. 31 Fluorescence Excitation Sources ................................................................................................................. 32 Fluorescence Theory ................................................................................................................................... 33 Spectroscopy of Organic Pigments .................................................................................................................. 35 Chlorophyll .................................................................................................................................................. 35 Theremino System – Spettrometro_ENG – Page 2 Phycoerythrin .............................................................................................................................................. 37 Anthocyanins as pH Indicator ...................................................................................................................... 38 Carotenoids ................................................................................................................................................. 40 Betalaine ...................................................................................................................................................... 41 Spectroscopy of Fluorescent Dyes................................................................................................................... 43 Stilbenes – Triazine (Optical Brightener) ..................................................................................................... 43 Fluorescein Sodium (Uranine) ..................................................................................................................... 44 Eosin ............................................................................................................................................................ 45 Acridine Orange ........................................................................................................................................... 46 Rhodamine B ............................................................................................................................................... 47 Rhodamine 6G ............................................................................................................................................. 48 Green Fluorescent Dye ................................................................................................................................ 49 Methylene Blue ........................................................................................................................................... 50 Crystal Violet ................................................................................................................................................ 51 Methylene Blue – Malachite Green – Crystal Violet – Acriflavine (Preparation for Fungal infections) ...... 52 Phthalocyanine ............................................................................................................................................ 53 Erythrosine .................................................................................................................................................. 54 Coumarin ..................................................................................................................................................... 55 Spectroscopy of Edible Oils ............................................................................................................................. 56 “Extra Vergine” Olive Oil ............................................................................................................................. 56 Peanut Oil .................................................................................................................................................... 57 Sunflower Oil ............................................................................................................................................... 58 Corn Oil ........................................................................................................................................................ 58 Soybean Oil .................................................................................................................................................. 58 Almond Oil ................................................................................................................................................... 59 Sesame Oil ................................................................................................................................................... 59 Castor Oil ..................................................................................................................................................... 59