Importance

Loading Importance Indicators...

Abstract

An optical particle analyzer in which the size of a particle in a particle stream is determined from the intensity or the duration of light scattered from it. A laser beam is directed transversely onto the stream and scattering occurs at the beam focus. To ensure that only particles which traverse the center of the beam are considered, a smaller, validating beam concentric with the main beam also produces scattered light. A pulse from the narrow beam coincident with one from the broad beam confirms that the associated particle has passed through the center of the broad beam and warrants consideration and assessment. A further narrow beam spaced from the first provides a time delay, dependent on particle velocity, between interception of the two narrow beams by a particle. Particle velocity is thus measured.

Loading the Abstract Image...

First Claim