Optical readout of superheated emulsions

Prompted by earlier studies on position-sensitive measurements of bubble distributions in three-dimensional (3D) dosimetry applications, optical read-out systems for superheated emulsions have been investigated and developed for bubble imaging and counting. The approach relies on light scattering by the bubbles in the emulsions either to determine attenuation profiles for optical tomography or to determine the integral number of bubbles for personal dosimetry applications. Optical tomography is clearly suitable for the development of bench-top systems for the analysis of the 3D dose distributions from brachytherapy sources. However, the approach requires optimization in terms of scanning and image reconstruction parameters. This study also suggests that compact devices based on scattered light measurements may be a viable option for personal dosimetry applications. Once fully developed, they should permit a real-time read-out of bubble vaporizations, independent of radiation dose rate and vibration or noise levels.