A Continued Study of Optical Sound Generation and Amplification
Abstract
During the past year, research has concentrated on optoacoustic generation in fluids, ultrasonic absorption in water/polymer mixtures, and sound propagation through a gas with a nonequilibrium distribution of internal energy states. Preliminary optoacoustic measurements in water and propanol demonstrate that the theory explains experimental results for these weakly absorbing fluids. Attention then shifted to a strongly absorbing fluid with relaxing internal energy states, CS2. Initial measurements in CS2 reflect a non-linearity of signal strength with increasing input energy and the formation of visible bubbles near the optical focal point. A theoretical model for the optoacoustic signal as a function of time in the linear regime (energies too low for bubble formation) has been developed. A new system to measure small absorption (approx. 1 db/m) in fluids in the frequency range 90 KHz to 1 MHz has been tested. Measurements in distilled water indicate that this system is capable of measuring attenuation as small as 0.05 dB/m.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 31, 1987
- Accession Number
- ADA188362
Entities
People
- F. Douglas Shields
- Henry E. Bass
Organizations
- University of Mississippi