The Doppler effect in Fabry-Perot cavities with suspended mirrors is analyzed. The Doppler shift, which is intrinsically small, accumulates in the cavity and becomes comparable with or greater than the linewidth of the cavity if the cavity's finesse is high or its length is large. As a result, damped oscillations of the cavity field occur when one of the mirrors passes a resonance position. A f...

The Doppler effect, which occurs on the reflection of ultrasound from moving blood or tissue, is observed as a shift in frequency of the reflected ultrasound from that of the incident ultrasound. This Doppler shift has been widely used in clinical practice as a means of measuring blood velocity. Two types of Doppler Imaging are often discussed as facilities on ultrasonic scanners, namely Colour...

Displacement measuring interferometry is based on measuring the Doppler frequency shift that a beam of radiation undergoes upon reflection off a mirror connected to a moving stage. Usually the velocity of the reflecting stage is very small compared to the speed of light and is therefore deduced using the classical expression for the Doppler shift. We calculate relativistic corrections to the Do...

Since the discovery of planets orbiting nearby solar-type stars through very precise Doppler-shift measurements has become possible, the role of methods used to analyze such observations has grown significantly. The widely employed model-dependent approach based on the least-squares fit of the Keplerian motion to the radial-velocity variations can be, as we show, unsatisfactory. Thus, in this p...

The generation of laser-driven dense relativistic electron layers from ultra-thin foils and their use for coherent Thomson backscattering is discussed, applying analytic theory and one-dimensional particlein-cell simulation. The blow-out regime is explored in which all foil electrons are separated from ions by direct laser action. The electrons follow the light wave close to its leading front. ...

A Phased Array Doppler Sonar (PADS), as developed at SIO, images both acoustic backscatter intensity and Doppler shift over areas up to 90 degrees in bearing by 500 m in range. Sequences of images are recorded continuously for up to two months, with individual “pings” 0.5 to 1.0 seconds apart. The images permit two independent estimates of the mean velocity to be formed over the imaged area: on...