In this work, the Foucault knife-edge test, which has traditionally been known as the classic test for optical imaging devices, is used to characterize an acoustic lens for operation at 1.2 GHz. A confocal laser scanning microscope (CLSM) was used as the illumination and detection device utilizing its pinhole instead of the classical knife edge that is normally employed in the Foucault test. Information about the geometrical characteristics, such as the half opening angle of the acoustic lens, were determined as well as the quality of the calotte of the lens used for focusing. The smallest focal spot size that could be achieved with the examined lens employed as a spherical reflector was found to be about 1 μm. By comparison to the idealized resolution a degradation of about a factor of 2 can be deduced. This limits the actual quality of the acoustic focus.

Date Published: 9 April 2010
PDF: 10 pages
Proc. SPIE 7650, Health Monitoring of Structural and Biological Systems 2010, 76501W (9 April 2010); doi: 10.1117/12.847412

Published in SPIE Proceedings Vol. 7650:
Health Monitoring of Structural and Biological Systems 2010
Tribikram Kundu, Editor(s)