Abstract: A method for determining a distribution of events, a method for determining a distribution of particle sizes in a sample of air, and an apparatus for performing the same are provided. The method includes obtaining a measured ensemble property distribution function for one or more events, generating one or more theoretical ensemble property distribution functions based on Poisson statistics using one or more model parameters, and determining an event parameter property distribution function by fitting one or more of the theoretical ensemble property distribution functions to the measured ensemble property distribution function using a forward inversion algorithm.

Abstract: Through discrimination of the scattered signal polarization state, a lidar system measures a distance through semi-transparent media by the reception of single or multiple scattered signals from a scattering medium. Combined and overlapped single or multiple scattered light signals from the medium can be separated by exploiting varying polarization characteristics. This removes the traditional laser and detector pulse width limitations that determine the system's operational bandwidth, translating relative depth measurements into the conditions of two surface timing measurements and achieving sub-pulse width resolution.

Abstract: Through discrimination of the scattered signal polarization state, a lidar system measures a distance through semi-transparent media by the reception of scattered signals from a first surface and scattered signals from a second surface. Combined and overlapped light signals scattered from the two surface signals can be separated by exploiting their differing polarization characteristics. This removes the traditional laser and detector pulse width limitations that determine the system's operational bandwidth, translating relative depth measurements into the conditions of single surface timing measurements and achieving sub-pulse width resolution.