Patent ID: 9709594
Date: 2017-07-18
CPC Classifications: G01P,G01S

Claim:
1. An apparatus for noncontact open channel fluid flow profiling comprising: a self-mixing and self amplifying narrow linewidth laser diode; an optical system positioned and constructed to focus light from the laser diode to a focal point within a flowing stream and applying Doppler-shifted backreflections from scatterers within the flowing stream to the self-mixing and self amplifying laser diode, wherein a Doppler beat is created; at least one microprocessor connected to the self-mixing and self amplifying laser diode that converts a time-domain Doppler beat signal into a frequency spectrum using an FFT algorithm; the at least one microprocessor including software wherein the velocity of the flowing stream at the focal point is determined from a frequency spectrum; said at least one microprocessor including a program that focuses light from the laser at a first focal point and a second focal point along a beam; wherein the distance between the first focal point and the second focal point is calculated; and intensities of the light backscattered from the first focal point and the second focal point as measured by the laser diode are recorded, wherein said at least one microprocessor includes a program for determining the turbidity from the difference between the light intensities at the first and second focal points.