Naprava za karakterizacijo polarizacije laserske svetlobe

magistrsko delo magistrskega študijskega programa II. stopnje Strojništvo

Janez Lapajne (Author), Rok Petkovšek (Mentor), Vid Agrež (Co-mentor)

Abstract

Merjenje polarizacije svetlobe predstavlja pomembno področje karakterizacije laserske svetlobe. V magistrskem delu je skonstruiran polarimeter, ki omogoča točno merjenje vseh polarizacijskih stanj svetlobe v realnem času. Za zasnovani optomehatronski sistem je prikazana izdelava merilne in krmilne enote, ter izbira optičnih, mehanskih in elektronskih komponent. Izdelano je električno vezje, ki omogoča lažje povezovanje med posameznimi komponentami. Na njem je integriran mikrokrmilnik, ki predstavlja logično enoto izdelanega polarimetra. Na mikrokrmilniku je implementiran krmilni algoritem, ki omogoča merjenje in komunikacijo z uporabnikom. Polarimeter je zasnovan na principu popisa rotirajoče retardacijske ploščice in fiksnega polarizatorja s Stokes-Muller-jevo formulacijo. V primeru zamenjave optičnih elementov je uporabljena tehnika primerna za različne valovne dolžine. Za zamenjavo optičnih elementov je zasnovan postopek kalibracije. Uporabnik z izdelanim polarimetrom upravlja preko LCD zaslona ali osebnega računalnika. Za ta namen je izdelan uporabniški vmesnik, ki omogoča krmiljenje, kalibracijo in analizo meritev. Za kontrolo pravilnosti delovanja izdelanega polarimetra je zasnovan postopek določitve negotovosti. Pri tem je uporabljen laserski izvor z valovno dolžino [lambda]=1064 nm, frekvenco bliskov 1 Mhz in dolžino bliskov t [sub] FWHM = 1 ns. Z izdelanim polarimetrom lahko merimo Stokes-ove parametre z razširjeno merilno negotovostjo 0,02 in maksimalno frekvenco merjenja 3 vzorce/s.

Keywords

magistrske naloge;Stokes-ova formulacija;merjenje polarizacije;snovanje polarimetra;snovanje električnega vezja;laserska svetloba;optimizacija;

Data

Language:	Slovenian
Year of publishing:	2020
Typology:	2.09 - Master's Thesis
Organization:	UL FS - Faculty of Mechanical Engineering
Publisher:	[J. Lapajne]
UDC:	535.51:681.5.08(043.2)
COBISS:	27427075
Views:	1316
Downloads:	174
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	English
Secondary title:	Device for characterization of laser light polarization
Secondary abstract:	Measuring light polarization is important for the characterization of the laser light. In the thesis, we devise a polarimeter that enables accurate measurement of light polarization states in real time. For the devised optomechatronical system we show the realization of the measuring and control units, and the choice of optical, mechanical and electronic components. We devised an electrical circuit that facilitates the connections among individual components. On the electrical circuit, we integrated a microcontroller that represents a logical unit of the devised polarimeter. A control algorithm is implemented on the microcontroller which enables data acquisition and communication with the user. The polarimeter uses the principle of rotating optical waveplates and a fixed polarizer with Strokes-Muller formulation. Measuring at different wavelengths can be achieved by a simple substitution of the optical elements. For this we devised a calibration procedure. A user can control the polarimeter via LCD screen or a personal computer. For this purpose, a user interface was written that allows for control, calibration and analysis of measurements. We established a procedure for determining the measurement uncertainty in order to control for the correct functioning of the devised polarimeter. To achieve that, we used a laser source with [lambda]=1064 nm wavelength, \mbox{1 Mhz} laser beam frequency and t [sub] FWHM = 1 ns beam length. With the devised polarimeter, we can measure Strokes parameters with an expanded measurement uncertainty of 0.02 and a maximum frequency measurement of 3 samples/s.
Secondary keywords:	master thesis;Stokes formulation;polarization measurement;design of polarimeter;design of printed circuit board;laser light;optimization;
Type (COBISS):	Master's thesis/paper
Study programme:	0
Thesis comment:	Univ. Ljubljana, Fak. za strojništvo
Pages:	XXIV, 94 str.
ID:	12014881