3rd French conference on acoustics
J. Phys. IV France 04 (1994) C5-1285-C5-1288
Imagerie ultrasonore haute résolutionM. BERSON1, G. FEUILLARD2, S. DIRIDOLLOU2, M. LETIECQ2 and L. POURCELOT2
1 Unité INSERM 316, Laboratoire de Biophysique Médicale, Faculté de Médecine, 2 Bis Boulevard Tonnellé, 37032 Tours cedex, France
2 GIP Ultrasons, Laboratoire de Biophysique Médicale, Faculté de Médecine, 2 Bis Boulevard Tonnellé, 37032 Tours cedex, France
High resolution acoustical imaging involves hard constraints for the ultrasonic probes which are used : a high resonance center frequency, a very wide bandwidth, a good sensitivity and a strong focusing of the beam. The system which is described uses two kinds of focused transducer : a very broad band 17 MHz center frequency transducer (PZT), and a 45 MHz copolymer transducer. The focal distances are respectively 7 mm and 6 mm in water. The movement of the transducer provides a 6 mm wide and 5 mm deep echographic cross-section with at the rate of 15 images/s. The resolution is respectively at 17 MHz and 45 MHz, 80 µm and 60 µm in axial and 250 µm and 60 µm in lateral in the focal zone. The device was tested on fantoms in water and in vivo with applications in Dermatology.
© EDP Sciences 1994