Commissariat a L'energie Atomique

Commissariat &#xc0; L'&#xc9;nergie Atomique Et Aux &#xc9;nergies Alternatives

Laboratoire Central Des Ponts Et Chaussees

Ecole Nationale Des Ponts Et Chaussees

Anne Ghis

Marc Delaunay

Berengere Lebental

Jean-Frederic Clerc

Patrice Ouvrier-Buffet

Elisabeth Delevoye

Marie-Claude Gentet

Nathalie Rolland

Sami Ajram

Bérengère Lebental

Aziz Benlarbi-Delai

A device for producing an amorphous carbon layer by electron cyclotron resonance plasma, the device including a plasma chamber; a gas supply; a magnetic mirror; a waveguide extending along a reference axis; a system for injecting microwave power; a magnetic field generator for generating a magnetic field in the plasma chamber, the magnetic field generator being configured to create a beam of magnetic field lines along which plasma is diffused; a target made from carbon; a substrate holder, wherein the target is arranged at a distance from the reference axis of between R/2 and R, and wherein the device further includes a screen arranged between the waveguide and the substrate holder.

Device for producing an amorphous carbon layer by electron cyclotron resonance plasma

A capacitive vibrating-membrane ultrasonic transducer includes a carrier with a cavity, a vibrating membrane fastened to the carrier and covering the cavity, and a conductive element separated from the membrane by the cavity. The vibrating membrane has a resonant frequency in membrane mode fm and a resonant frequency in plate mode fp according to the relationship fm&#x3e;fp. An exciting circuit has terminals connected to the vibrating membrane and the conductive element, and is configured to apply, across its terminals, an electrical signal the maximum frequency fo according to the relationship fm&#x3e;1.5*fo; or a measuring circuit is connected to the vibrating membrane and the conductive element and configured to measure capacitance variations up to a frequency fo.

Wide-passband capacitive vibrating-membrane ultrasonic transducer

A microelectromechanical system includes a membrane of amorphous carbon having a thickness between 1 nm and 50 nm, and for example between 3 nm and 20 nm.

Membrane of amorphous carbon and MEMS including such a membrane

The invention concerns a device for analysing the microporosities of a given material including at least two phases, one of which is a fluid phase, including: multiple sensors () incorporated in the given material (M), where each of the sensors includes one or more cMUT acoustic and capacitive transducers.

Method and device for acoustic analysis of microporosities in a material such as concrete using multiple cMUTs transducers incorporated in the material

A cMUT-type capacitive electroacoustic transducer including: at least one membrane configured to oscillate under effect of an electric field and/or an acoustic wave, wherein the membrane is formed from one or more layers of juxtaposed nanotubes or nanowires or nanorods, and an acoustic imaging device or UHF sonar including such transducers.

CMUT cell formed from a membrane of nanotubes or nanowires or nanorods and device for ultra high frequency acoustic imaging including multiple cells of this kind

A sampling device for high frequency signal that propagates in a propagation structure. The device comprises a first stage (AIC) to sample a first signal at a first time tand at least one second stage (AIC) in series with the first stage to take a second sample representative of the first sample, starting from the first sample, taken at a second time tgreater than t, the life-time of the second sample being longer than the life-time of the first sample.

Sampling device for a high frequency electrical signal

An electrical sampler device has a plurality of samplers for sampling an electrical signal. Each of the samplers is responsive to a corresponding sampling point. The electrical sampler device also has a propagation line coupled to each of the plurality of samplers, for propagating a sampling signal. One or more delay elements are coupled to the propagation line. The delay means elements delay the propagation of the sampling signal between two neighboring samplers.

Electrical sampler for non-simultaneous sampling

The invention relates to a single short radiation pulse analyzer comprising radiation detectors that convert this radiation into an electrical signal, and means of measuring this signal by sampling at different times.

Single short radiation pulse analyzer having signal sampling delay time

A sampler adapted for the measurement of ultra-short electrical pulses of a very broad spectrum. The sampler has an electrical pulse propagation structure (i.e., propagation line) made up of a series of line sections. The line sections are linked to one another by switches which can be commanded electrically. Normally, the switches are on or closed. The taking of samples can occur by opening the switches to thereby confine the totality of the charges carried by the pulse to the different sections that make up the propagation line. Once the switches are opened, the charge may be sampled in each section.

Switched electrical pulse propagation sampler

A process for regulating the brightness of a microdot fluorescent screen and apparatus for performing this process. The screen is of the matrix type and is addressed by a scan of the rows, a pixel being formed at each row-column intersection. For an illuminated pixel, for a selection time T of the corresponding row, a quantity of charges is emitted by the associated microdots. The brightness is regulated during the selection time of each row by controlling the quantity of charges emitted by the microdots of each pixel to be illuminated, the charge quantity being identical for each pixel.

Microtip fluorescent matrix screen addressing process

A process and device for controlling a matrix screen displaying gray levels, wherein during the line time T activation signals are delivered to the columns of the screen for a time depending on the gray level i of the image point in question and equal to (T/N).Nil, where O.ltoreq.i.ltoreq.m.ltoreq.N, the Nils forming a strictly increasing sequence of i of first term zero and of last term lower than or equal to N, the Nils being so selected as to obtain a predetermined distribution for the light intensities of the different gray levels. Application to the control of microdot or liquid crystal matrix screens.

Growing community of inventors

Saint Martin d'Heres, France

Anne Ghis