Share Email Print

Journal of Biomedical Optics

Time-resolved study of the mechanical response of tissue phantoms to nanosecond laser pulses
Format Member Price Non-Member Price
PDF $20.00 $25.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

We present a time-resolved study of the interaction of nanosecond laser pulses with tissue phantoms. When a laser pulse interacts with a material, optical energy is absorbed by a combination of linear (heat generation and thermoelastic expansion) and nonlinear absorption (expanding plasma), according to both the laser light irradiance and material properties. The objective is to elucidate the contribution of linear and nonlinear optical absorption to bubble formation. Depending on the local temperatures and pressures reached, both interactions may lead to the formation of bubbles. We discuss three experimental approaches: piezoelectric sensors, time-resolved shadowgraphy, and time-resolved interferometry, to follow the formation of bubbles and measure the pressure originated by 6 ns laser pulses interacting with tissue phantoms. We studied the bubble formation and pressure transients for varying linear optical absorption and for radiant exposures above and below threshold for bubble formation. We report a rapid decay (of 2 orders of magnitude) of the laser-induced mechanical pressure measured (by time-resolved shadowgraphy) very close to the irradiation spot and beyond 1 mm from the irradiation site (by the piezoelectric sensor). Through time-resolved interferometry measurements, we determined that bubble formation can occur at marginal temperature increments as low as 3°C.

Paper Details

Date Published: 1 November 2011
PDF: 10 pages
J. Biomed. Opt. 16(11) 115001 doi: 10.1117/1.3644380
Published in: Journal of Biomedical Optics Volume 16, Issue 11
Show Author Affiliations
Francisco G. Perez-Gutierrez, Univ. Autónoma de San Luis Potosí (Mexico)
Santiago Camacho-López, Ctr. de Investigación Científica y de Educación Superior de Ensenada (Mexico)
Guillermo Aguilar, Univ. of California, Riverside (United States)

© SPIE. Terms of Use
Back to Top