The purpose behind the development of the SALD-7500nano was to provide a highly sensitive method for measuring low concentration of high light absorption nano particle size distributions. The device also allows extremely low concentrations of particles, on the order of 1 part per million or less to be measured. Micro bubbles in the 100 nanometer to 60 micrometer size range can also be detected, measured, and analyzed. All this can be done using a single light source, a single optical system, and a single measuring system. Particle size distribution can be measured in 1 second intervals, viewed, and saved for later statistical processing and 3D display. Special glass slides featuring a shallow indentation are included when it is desired to perform measurements on volumes in the order of 15 microliters.