Abstract
We demonstrate that absorption coefficient and reduced scattering coefficient of a small turbid object can be measured to high accuracy with a frequency-domain immersion technique. For this technique the sample is immersed in a calibrated scattering medium and the optical properties are obtained from a differential measurement. Compared with conventional approaches, the immersion technique improves accuracy, minimizes variations owing to probe coupling and motion, reduces the effects of boundary conditions, and offers simple and rapid measurement once the immersion medium is calibrated. Accuracy tests of immersion-based measurements of and agree with reference values to within 3.6% and 2.6%, respectively. These tests are limited by the accuracy of the reference samples rather than by the accuracy of the immersion medium or the precision of the immersion approach. We demonstrate the in vivo capabilities of the technique through time-resolved measurements of and for a human hand during cuff occlusion on the upper arm.
© 1999 Optical Society of America
Full Article | PDF ArticleMore Like This
Martina Gerken and Gregory W. Faris
Opt. Lett. 24(14) 930-932 (1999)
Martina Gerken, Devon Godfrey, and Gregory W. Faris
Opt. Lett. 25(1) 7-9 (2000)
Olivier Coquoz, Lars O. Svaasand, and Bruce J. Tromberg
Appl. Opt. 40(34) 6281-6291 (2001)