J. Phys. IV France
Volume 125, June 2005
Page(s) 153 - 156

J. Phys. IV France 125 (2005) 153-156

DOI: 10.1051/jp4:2005125035

Measurement of low optical absorption in highly scattering media using the thermal lens effect

J.A. Olivares1, A. García-Valenzuela1, F.L.S. Cuppo2, F. Curiel1, G. Ortiz1, 2 and R.G. Barrera1, 2

1  Centro de Investigación en Polímeros, COMEX, Blvd. Ma Avila Camacho 138, PH 1 y 2, Lomas de Chapultepec, CP 11560, Mexico DF, Mexico
2  Instituto de Física, Universidad Nacional Autónoma de México, Apartado Postal 20-364, 01000, Mexico DF, Mexico

In this work we show that the thermal lens effect can be applied to highly scattering and weakly absorbing materials. We apply the thermal lens effect and the z-scan technique to estimate the effective absorption coefficient of a suspension of TiO2 particles with a mean diameter of 220 nm at two wavelengths: 488 nm and 514 nm. From the effective absorption coefficient we estimate the absorption cross section of the particles.

© EDP Sciences 2005