PVF2 phase shifters and modulators for fiber‐optic sensors

Birefringent Achromatic Phase Shifters for Nulling Interferometry and Phase Coronagraphy

Achromatic Phase Shifters are mandatory components in the field of nulling interferometry and phase coronagraphy. Indeed, in order to detect faint objects (e.g. exo-planets) around a central bright star, one must attenuate the latter by all means. To do this, the most efficient way is to “create” a destructive interference on the blinding light. This technique is called nulling and is common to...

PVF2 Transducers for NDT

We have investigated the spatial dependence of the longitudinal piezoelectric stress constant e of PVF . Experiments were performed on a series of no.minally identical brass-backed PVF longitudinaF wave t~ansducers in water using commercial PVF7 film. Computer programs were designed t6 predict the performance of the transducers as a function of e (Z) , the thickness mode piezoelectric stress co...

Guided resonance reflective phase shifters

We present reflective phase shifters based on high contrast gratings resting on a low-index spacer backed by a metallic mirror. The guided resonance of the grating combined with the reflection from the metallic mirror leads to an all-pass filter with 2π phase shift variation and unity reflectivity across the resonance. We present simulations, fabrication and measurement of passive devices fabri...

Microwave And Millimeter-Wave Ferrite Phase Shifters

microstrip arrays using simple integratedferrite phase shifters

A phase-steered microstrip antenna array is presented, suitable for application as a mobile vehicle satellite terminal. Phase shifters are implemented on a hybrid dielectric-ferrite substrate, and use is made of the phase transition near the cut-off region of the biased ferrite. Small permanent magnets and carefully biased ferrites remove the need for large applied electromagnetic fields. 2-, 3...