20.500.12556/RUL-187102 Zasnova sistema za merjenje kavstike anularnega laserskega žarka Design of a System for Measuring the Caustic of an Annular Laser Beam Kavstika laserskega žarka in z njo povezana porazdelitev intenzitete laserskega žarka (PILŽ) neposredno vplivata na kakovost procesa laserskega usmerjenega nanašanja (LUN) kovinskega prahu ali žice. Obstoječi merilni sistemi so prilagojeni predvsem za Gaussove laserske žarke nižjih moči in manjših premerov, zato niso primerni za mer- jenje kavstike anularnega laserskega žarka (ALŽ) velikega premera in moči, kakršnega uporablja obravnavani sistem LUN. V diplomskem delu je zasnovan sistem za merje- nje kavstike anularnega laserskega žarka (SMKALŽ), ki temelji na zajemanju PILŽ s kamero s CMOS senzorjem na različnih razdaljah vzdolž osi ALŽ. Za zmanjšanje moči ALŽ na raven, ki jo senzor še lahko izmeri, smo uporabili polprepustno zrcalo z antireflektivnim premazom in svetlobni filter. Opredelili in izbrali smo vse potrebne optične in mehanske komponente sistema, izdelan je bil 3D model sestava in ocenjena cena sistema. Analizirane so bile tudi pričakovane merilne napake, med drugim vpliv podvojenega odboja in odvisnost odbojnosti od vpadnega kota. Zasnovani SMKALŽ bo omogočal hitrejše, enostavnejše in cenejše merjenje kavstike ALŽ v primerjavi z obstoječimi metodami uporabljenimi v Laboratoriju za Sinergetiko. The caustic of a laser beam and the associated laser beam intensity distribution (LBID) directly affect the quality of the laser-directed energy deposition (LDED) process used to process metal powder or wire. Existing measurement systems are typically designed for lower-power, smaller-diameter Gaussian laser beams and are therefore unsuitable for measuring the caustic of the annular laser beam (ALB) of large diameter and power used in the considered LDED system. This thesis presents the design of a system for measuring the caustic of an annular laser beam (SMCALB), based on capturing the LBID with a CMOS camera at multiple positions along the beam path. To reduce the beam’s power to a level the sensor can measure, the system uses a partially reflec- tive mirror with an antireflective coating together with an optical filter. All required optical and mechanical components were defined and selected, a 3D assembly model was created, and the cost of the system was estimated. Expected measurement errors were also analyzed, including the effect of double reflection and the angle dependence of reflectivity. The designed system enables faster, simpler, and more affordable me- asurement of the annular laser beam’s caustic compared to existing methods used at the Laboratory for Synergetics. kavstika laserskega žarka anularni laserski žarek porazdelitev intenzitete laserskega žarka lasersko usmerjeno nanašanje CMOS senzor laser beam caustic annular laser beam laser beam intensity distribution laser-directed energy deposition CMOS sensor true false false [G. Myint] Slovenski jezik Angleški jezik Diplomsko delo/naloga 2026-09-09 08:30:39 2026-09-09 08:30:42 2026-09-10 04:30:43 0000-00-00 00:00:00 2026 0 Ljubljana 0 XII, 48 f. 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 621.375:535.4(043.2) 289701 290516227 49557.pdf 49557.pdf 1 851BBABFA223CD18B022612CB163A048 333d766d0696e39565c14a932d593e737a90824292df21092208f465d6ca86ca f843740b-ac17-11f1-8bc5-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=246542 49558.pdf 49558.pdf 1 A766F8D0E0ED8A17CD1BDE9C8BDF3CD4 39d3c5dfd519b96359a68f266f0af80fe083e0a4f99523e332cf301bde0e10ec f8441290-ac17-11f1-8bc5-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=246543 49559.pdf 49559.pdf 1 79C382E65BA313845605B69C93BB0E1D c205c04e975b3f1f9847ed30253ae52f36d85d25e776d27158974fddd3100bf7 f844667e-ac17-11f1-8bc5-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=246544 Fakulteta za strojništvo 0 0 0