Disclosed herein is a novel, compact optical particle identification and characterization system and method of use within both gaseous and liquid media. The system can implement both elastic and inelastic light scattering techniques simultaneously under the same sensor platform. By separating the sensing components from the electro-optical unit and using optical fibers for interconnection, only the sensing components need to be exposed to the environmental conditions. This reduces the design constraints on the electro-optical unit and permits the incorporation of optical components into the sensing probe that can withstand high-temperature, high-pressure, and corrosive environments. Thus, the system can be used in benign, moderate, and harsh environments.