Nadgradnja sistema za merjenje slabljenja optičnih vlaken

PANIĆ, DAMJANA (author), Krč, Janez (mentor)

V tem diplomskem delu je osrednja tema nadgradnja sistema za meritev slabljenja na optičnih vlaknih. Nadgradnja je bila potrebna zaradi slabe ponovljivosti. Posumili smo, da vsa izstopna svetloba iz laserskega vlakna ne pade na detektor optično spektralnega analizatorja Pri merjenju slabljenja in postavitvi sistema za merjenje slabljenja ima zelo veliko vlogo numerična aprtura vlakna. Laserska vlakna imajo aperturo okoli 0.48 in posledično tudi dokaj širok izstopni žarek. Zato je potrebno biti pozoren predvsem na to, da vsa svetloba pade na detektor, v nasprotnem primeru ne dobimo pravih meritev. To je bil tudi problem pri starem sistemu, vlakno je bilo namreč preveč oddaljeno od detektorja za tako veliko numerično aprturo. V nov sistem sem vključila prekinjevalnik svetlobe, monokromator, lock-in ojačevalnik, xyz mizico in nov detektor. Bistveno vlogo imata ravno xyz mizica in detektor. Pred dovolj velik detektor sem postavila xyz pozicijsko mizico za pričvrstitev vlakna nanjo. Tako sem vlaknu omogočila, da se lahko približala čisto do detektorja in preprečila uhajanje izstopnega snopa izven detektorske površine. Naredila sem še 2 seriji testnih meritev, da preverim ponovljivost.

• Language: Slovenian
• Keywords: lasersko vlakno, slabljenje vlakna, optične komunikacije
• Work type: Bachelor thesis/paper
• Organization: FE - Faculty of Electrical Engineering
• Year: 2017
• PID: 20.500.12556/RUL-95098
• Publication date in RUL: 14.09.2017

Secondary language

• Language: English
• Title: Upgrade of the system for measurements of optical fiber attenuation

Abstract

This thesis deals with the update of the system for the measurement of optical cladding attenuation. The update was necessary due to poor repeatability. We suspected that not all exit light from the laser fibre falls on the detector of optical spectrum analyser. Numerical aperture of the fibre plays a great role when measuring the attenuation and setting up the measuring system for the attenuation. The numerical aperture of the optical fibre is around 0.48; consequently, the fibre has also a wide exit beam. This is why we must ensure that all the light falls on a detector otherwise the measurement is incorrect. This was the problem of the old system. The fibre with such large numerical aperture was too far away from the detector. In the new system, I included a chopper, a monochromator, a lock-in amplifier, a xyz table and a new detector. The detector and the xyz table are essential. I placed the xyz table in front of the suitably large detector and the fibre could fastened on the table. The fibre was then able to approach the detector and I prevented the leakage of the exit beam out of the detector. I made additional two test measurements to check the repeatability.

• Keywords: laser fibre, cladding attenuation, optical communications