Fokusiranje lasersko povzročenih tlačnih valov s ploščato optoakustično lečo

magistrsko delo magistrskega študijskega programa II. stopnje Strojništvo

Laura Levstik (Author), Matija Jezeršek (Mentor), Daniele Vella (Co-mentor)

Abstract

Z optoakustičnim pojavom lahko vplivamo na dele materiala globoko pod obsevano površino. Ta pretvori energijo laserske svetlobe v tlačno valovanje, ki se širi v notranjost. S fokusiranjem valov dosežemo lokalno velike amplitude, kar ima velik potencial na področju medicine. Problem obstoječih sistemov je pomanjkanje enostavne in učinkovite metode fokusiranja, ki bi omogočala dinamično spreminjanje globine in velikosti fokusiranega akustičnega polja. V ta namen smo razvili prototipno optoakustično lečo, kjer smo na ploščat stekleni substrat na eni strani nanesli kompozit, na drugi pa naredili obročasto masko iz bakra. Lečo smo potopili v vodo, kjer smo jo obstreljevali z laserskimi bliski in merili nastale tlačne valov s hidrofonom. Enak model smo definirali v programu Ansys APDL ter opravili numerične analize. Eksperimentalne in numerične rezultate smo analizirali in primerjali, kar je pokazalo delno ujemanje. S simulacijami in eksperimenti smo dobili poglobljeno razumevanje delovanja ploščate optoakustične leče.

Keywords

magistrske naloge;fokusiranje;tlačni valovi;optoakustika;optoakustična leča;hidrofon;simulacije MKE;

Data

Language:	Slovenian
Year of publishing:	2024
Typology:	2.09 - Master's Thesis
Organization:	UL FS - Faculty of Mechanical Engineering
Publisher:	[L. Levstik]
UDC:	681.7.075:534:535.374(043.2)
COBISS:	219842563
Views:	202
Downloads:	73
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	English
Secondary title:	Focusing of laser generated pressure waves using flat optoacoustic lens
Secondary abstract:	With the optoacoustic phenomenon, we can affect parts of the material deep below the irradiated surface. This converts the energy of the laser light into pressure waves, which propagate inside. By focusing the waves, locally large amplitudes are achieved, which has great potential in the field of medicine. The problem with existing systems is the lack of a simple and efficient focusing method that would allow the depth and size of the focused acoustic field to be dynamically changed. For this purpose, we developed a prototype optoacoustic lens where we applied a composite to a flat glass substrate on one side and made an annular copper mask on the other. The lens was immersed in water, where it was illuminated with laser pulses and the resulting pressure waves were measured with a hydrophone. The same model was defined in the Ansys APDL program and numerical analyses were performed. Experimental and numerical results were analyzed and compared, which showed a partial match. Through simulations and experiments, we have gained an in-depth understanding of the operation of a flat optoacoustic lens.
Secondary keywords:	master thesis;focusing;pressure waves;optoacoustics;optoacoustic lens;hydrophone;FEM analysis;
Type (COBISS):	Master's thesis/paper
Study programme:	0
Embargo end date (OpenAIRE):	1970-01-01
Thesis comment:	Univ. Ljubljana, Fak. za strojništvo
Pages:	XXIV, 54 str.
ID:	25050596