Nonmechanical scanning laser Doppler velocimetry for distribution measurements of two-dimensional velocity vectors based on optical quadrature detection.

This paper proposes a nonmechanical scanning laser Doppler velocimeter (LDV) for measuring the distribution of two-dimensional velocity vectors. In the proposed LDV, an optical quadrature detection technique and a nonmechanical axial scanning technique are introduced into a reference-type LDV. Consequently, the LDV has a simple optical system without multiple light sources or frequency shifting and does not have any moving mechanisms in the probe. The experimental results obtained using a sensor probe setup indicate that the function of measuring two-dimensional velocity vectors and the scanning function are successfully demonstrated.