Extension of the theory of the fluid-filled optoacoustic cell

The theory of a cylindrical, pulsed optoacoustic cell is extended to include off-axis beam excitation and calculation of the resulting pressure at an arbitrary point. The theory is restricted to nearly transparent fluids, thus making a two-dimensional analysis adequate. Calculations based on the theory predict the initial pulse response for various beam excitation positions and provide a comparison with experiment. The dependence of subsequent pulse reflections on beam position is also computed.