Abstract: An optical to radio frequency detector comprises an optical guide for receiving two optical signal components having frequencies that differ by an amount corresponding to a radio frequency, and a radio signal guide coupled with an interaction zone of the optical guide for propagating a radio signal from the interaction zone at the radio frequency. The material of the interaction zone presents a second-order non-linear optical polarization characteristic to the propagation of the optical signal components, and the radio signal guide is in travelling-wave coupling with the interaction zone. A radio signal output is coupled with the radio signal guide.

Abstract: The invention relates to a device useful for non-invasive detection of the properties of a medium by means of interferometry. The device comprises an optical source which is used for illuminating a zone of the medium that is to be probed with a light beam, and an interferometer for splitting the light beam into a reference beam and a probe beam. The interferometer has a cutoff frequency for the automatic control of respective path lengths of the reference beam and of the probe beam. The device also comprises scanning means which, together with the probe beam, are used to scan the zone to be probed at an image acquisition frequency greater than the cutoff frequency.

Abstract: The invention relates to a device which is used for the non-invasive detection of an electric potential or field, of the spatial and/or the temporal derivatives thereof, in a medium with a linear or quadratic electrooptical effect. The inventive device comprises: an optical source which is used to illuminate at least one zone of the medium that is to be probed with a light beam, the path of which defines an optical axis; and means for mapping the phase shift of the beam in the zone to be probed. Measuring means which are used to map the light beam phase shift comprise a confocal microscope in which the zone to be probed is placed in order to form an image of a plane of said zone.

Abstract: The invention relates to a device which is used for the non-invasive detection of an electric potential or field, of the spatial and/or the temporal derivatives thereof, in a medium with a linear or quadratic electrooptical effect. The inventive device comprises: an optical source which is used to illuminate at least one zone of the medium that is to be probed with a light beam, the path of which defines an optical axis; and means for mapping the phase shift of the beam in the zone to be probed. Measuring means which are used to map the light beam phase shift comprise a confocal microscope in which the zone to be probed is placed in order to form an image of a plane of said zone.

Abstract: The invention relates to a device useful for non-invasive detection of the properties of a medium by means of interferometry. The device comprises an optical source which is used for illuminating a zone of the medium that is to be probed with a light beam, and an interferometer for splitting the light beam into a reference beam and a probe beam. The interferometer has a cutoff frequency for the automatic control of respective path lengths of the reference beam and of the probe beam. The device also comprises scanning means which, together with the probe beam, are used to scan the zone to be probed at an image acquisition frequency greater than the cutoff frequency.

Abstract: An optical to radio frequency detector comprising an optical guide (11 to 14) for receiving two optical signal components having frequencies that differ by an amount corresponding to a radio frequency, and a radio signal guide (15, 16) coupled with an interaction zone (14) of the optical guide for propagating a radio signal from the interaction zone at the radio frequency. the interaction zone (14) of the optical guide comprises an interaction material presenting a second-order non-linear optical polarisation characteristic to the propagatio of the optical signal components, and the radio signal guide (15,16) is in travelling-wave coupling with the interaction zone. the interaction material includes electrically orientated diazobenzene.

Abstract: A locally-outcoupled optical resonator has whispering gallery modes existing in a nearly circular resonator. Light is outcoupled by providing a local perturbing feature on the perimeter of the locally-outcoupled cavity resonator. The perturbing feature provides an outcoupling or loss mechanism that asymmetrically interacts with circulating whispering gallery modes, thereby making the resonator capable of uni-directional output.

Abstract: The invention concerns a method for optical recording of data on a photosensitive storage medium, characterized in that the data are encoded according to different possible states for the various components of a non-linear susceptibility tensor of the photosensitive medium and it consists in irradiating simultaneously at least a point of said support with write beams whereof the polarization is controlled for optical recording of a given non-linear susceptibility tensor on the photosensitive medium.

Abstract: The invention concerns a method for photographic recording a spatial distribution of linear and/or non-linear optical properties in a polymer material which consists in irradiating the material to modify the orientation of its molecules. The irradiation direction is perpendicular or oblique relative to the propagation direction(s) of the scanning beams.

Abstract: A locally-outcoupled optical resonator has whispering gallery modes existing in a nearly circular resonator. Light is outcoupled by providing a local perturbing feature on the perimeter of the locally-outcoupled cavity resonator. The perturbing feature provides an outcoupling or loss mechanism that asymmetrically interacts with circulating whispering gallery modes, thereby making the resonator capable of uni-directional output.

Abstract: The invention concerns a method for optical recording of data on a photosensitive storage medium, characterised in that the data are encoded according to different possible states for the various components of a non-linear susceptibility tensor of the photosensitive medium and it consists in irradiating simultaneously at least a point of said support with write beams whereof the polarisation is controlled for optical recording of a given non-linear susceptibility tensor on the photosensitive medium.

Abstract: The present invention relates to new noncentrosymmetric crystal structures consisting of an optionally substituted 2-amino-5-nitropyridinium halide.It also relates to a process for the preparation of these crystal structures. Finally, it relates to a device with an electro-optical effect comprising said crystal structure.

Abstract: The present invention relates to new noncentrosymmetric crystal structures consisting of an optionally substituted 2-amino-5-nitropyridinium halide.It also relates to a process for the preparation of these crystal structures. Finally, it relates to a device with an electro-optical effect comprising said crystal structure.

Abstract: The invention relates to a transparent sol-gel material which has a susceptibility of the second order X.sub.2, consisting of an inorganic matrix containing organic molecules which have nonlinear optical properties (ONLAOM) oriented in a preferential direction. The materials according to the invention lend themselves to the production of components making use of their linear and nonlinear optical properties (optical telecommunications, processing of the optical signal in analog or digital form, and the like).

Abstract: 2-amino-5-nitropyridinium salts are provided which are usable in non-linear and electrooptics.

Abstract: The present invention relates to new left-handed or right-handed monohydrogentartrate crystalline structures having nonlinear quadratic effects and a wide transparency range extending from the visible to the near infrared, consisting of optionally substituted 2-amino-5-nitropyridinium cations in combination with a polyanionic organic matrix formed of left-handed or right-handed monohydrogentartrate anions.It also relates to a process for the preparation of these crystalline structures consisting in mixing one mole of cation base with at least two moles of left-handed and/or right-handed tartaric acid. It finally relates to a device having an electrooptical effect containing said crystalline structure.

Abstract: In a method of manufacturing a planar optical waveguide based entirely on polymer materials an active polymer is deposited onto a semiconductor substrate between two layers of buffer polymers chosen so that the difference in refractive index on each side of the active polymer is between 0.005 and 0.5 and preferably between 0.01 and 0.4.

Abstract: An optical element, such as a wave guide, having non-linear optical properties, suitable for use in optical devices in which it is desirable to alter the characteristics of the light, comprising a transparent or reflecting substrate having at least a partial superficial coating comprising alternating monolayers of a first non-linear optical (NLO) compound of the formula: ##STR1## wherein R is an non-hydrophilic aliphatic or cycloaliphatic group containing from 8 to 40 carbon atoms;m is 1 or 2;R.sup.1 is NO.sub.2, CN or COOR.sup.2 ;R.sup.2 is H or C.sub.1-4 -alkyl;n is from 1 to 4; andR.sup.3 is H, a metal or a group containing a tetravalent N atom anda second NLO compound of the formula: ##STR2## wherein T is H, a metal or a group containing a tetravalent N atom;X is S, O, ##STR3## T.sup.1 is NO.sub.2, CN or COOY; Y is selected from H, C.sub.1-4 -alkyl, a metal or a group containing a tetravalent N atom;T.sup.2 and T.sup.

Abstract: The invention relates to novel paranitroaniline derivatives usable in non-linear optics and electrooptics, as well as to the preparation process for the same. These derivatives are in accordance with formula (I): ##STR1## in which one or more of the hydrogen atoms are optionally replaced by deuterium atoms. They are prepared by reacting one of the two pure optical isomers of 2-(hydroxymethyl)-pyrrolidine with a parahalogenonitrobenzene.The optically pure derivatives can be used in optical or optoelectronic devices.

Abstract: The invention relates to novel paranitroaniline derivatives usable in non-linear optics and electrooptics, as well as to the preparation process for the same. These derivatives are in accordance with formula (I): ##STR1## in which one or more of the hydrogen atoms are optionally replaced by deuterium atoms. They are prepared by reacting one of the two pure optical isomers of 2-(hydroxymethyl)-pyrrolidine with a parahalogenonitrobenzene.The optically pure derivatives can be used in optical or optoelectronic devices.