Improved scattering rejection in transmissometry using image-plane vortex phase masks

We experimentally demonstrate a 14% improvement in the signal-to-background power ratio in a laser transmissometer by augmenting a pinhole spatial filter with a vortex phase mask and beam block combination. This study addresses the significant challenge of measuring light transmission through turbid media, where signal loss due to scattering is a common problem. By integrating a vortex phase mask with a pinhole spatial filter, we achieve imaging through greater attenuation lengths than with either filter alone. This advancement has potential applications in underwater imaging, atmospheric optics, and other fields requiring precise optical measurements in scattering environments. The results provide a robust experimental validation of theoretical models and suggest new directions for future research in optical phase element design and transmissometry.