To quantify the relative transmittance of light through a particle-coated sheet of glass, a laser transmittance tester was built. This consisted of a diode laser and amplified photodiode detector. This measurement was critical for the development of the simultaneous schlieren and soot foil technique used in much of my detonation safety research.

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To determine the relative density within a particle cloud distributed by a shock wave, the device was also used. In this application, it was placed across the optically accessible section of the shock tube to measure cloud density by attenuation of laser light across the test section.