Accession Number : AD0495667

Title :   The Effectiveness of Plastic Focussing Lenses with High-Intensity Ultrasonic Radiation.

Descriptive Note : Technical rept.,

Corporate Author : BROWN UNIV PROVIDENCE RI

Personal Author(s) : Bronzo, Joseph A. ; Anderson, John Maxwell

Report Date : 30 JUN 1952

Pagination or Media Count : 18

Abstract : An investigation of the behavior of Plexiglas and Polystyrene lenses as focussing devices for ultrasonic radiation is described. A fixed frequency of 1 megacycle/second and intensities up to 6.6 W/sq cm were employed. Using a thermocouple probe to obtain records of intensity of radiation in a water tank, it was found that at about 2 W/sq cm the Plexiglas showed signs of physical breakdown. Up to the maximum intensities employed, Polystyrene showed no indication of damage, while at 6.6 W/sq cm the Plexiglas developed internal cavities near the outer edge of the lens, where the thickness was 4 mm.

Descriptors :   (*PLASTIC LENSES, PERFORMANCE(ENGINEERING)), (*ACOUSTIC EQUIPMENT, LENSES), (*UNDERWATER SOUND, ULTRASONIC RADIATION), ACRYLIC RESINS, STYRENE PLASTICS, YEASTS, FOCUSING, FAILURE(MECHANICS), DEGRADATION, INTENSITY, REFRACTION, CAVITATION, ACCEPTABILITY, RADIATION EFFECTS, THERMOCOUPLES, MEDIUM FREQUENCY, QUARTZ, WATER.

Subject Categories : Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE