A concept for the realisation of directional laser Doppler velocimeters (LDV), without having to use opto-electronic modulators like Bragg cells is presented. The concept is based on the use of a diode-pumped fibre laser, emitting at two different wavelengths. The two laser colours are used to generate two interference fringe systems in the measuring volume of the LDV system. The fringe systems...

There is a conflicting literature regarding the possible presence of adrenergic innervation of the retinal circulation. The effect of a histologically confirmed left superior cervical ganglionectomy on the total retinal blood flow in eight anaesthetised female cynomolgus monkeys was determined. Near total unilateral ocular sympathetic denervation was confirmed by ipsilateral miosis, supersensit...

A laser-Doppler velocimeter suitable for the measurement of mean and fluctuating flow velocities in water is described. Results of a study using this system in an axisymmetric turbulent jet of water and dilute polymer solutions are given. The laser-Doppler technique is better suited for such measurements than either Pitot tubes or heat-transfer gauges because the Doppler velocity measurements a...