This paper describes three novel techniques of multipoint measurement in optical fiber laser Doppler velocimetry, which make it possible to construct a system with an optical integrated circuit and optical fiber. Since such systems employ a unit light source and a unit optical detector, we will be able to measure the flow distribution using the systems. First, we demonstrate a new 2-dimensional measurement system using the optical integrated frequency shifter that we have originally designed on LiNbO3. Next, we construct a multipoint measurement system with on integrated optical switch and the distribution of oil flow is then measured using a four-point system. This method is based on time division multiplexing and each point is measured sequentially. Finally, the multipoint simultaneous measurement is demonstrated using a new type of system that employs laser diode modulation by injection current and many probes with an unbalanced optical fiber interferometer. Each system proved to be practical for air or oil flow measurement.
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