Abstract: Method for shielding a high-power laser apparatus (S) in which a laser beam is generated and then amplified in at least a first amplification stage, including spatial filtering (4) of the amplified laser beam, phase correction (3) carried out on the laser beam before it is spatially filtered, and a measurement of the aberrations (7) on the laser beam. The phase of the beam is corrected so as to produce a beam having minimal aberrations after spatial filtering. The shielding device (D, D?) implementing this method may in particular be employed in apparatus using an intense laser beam of high (terawatt) peak power and in proton therapy units.

Abstract: A super-resolution microscopy method includes forming an image of an emitting particle in a detection plane of a detector by a microscopy imaging system and correcting, by a wavefront-modulating device, at least some of the optical defects present between the emitting particle and the detection plane. The method further includes introducing, via the wavefront-modulating device, a deformation of the wavefront emitted by the emitting particle, of variable amplitude, allowing a bijective relationship to be formed between the shape of the image of the emitting particle in the detection plane and the axial position of the emitting particle relative to an object plane that is optically conjugated with the detection plane by the microscopy imaging system. The method further includes controlling the amplitude of the deformation of the wavefront by controlling the wavefront-modulating device, as a function of the given range of values of the axial position of the particle.

Abstract: A method for correcting a wave front analyzer, in which the analyzer detects a signal from an incident wave front to be analyzed (FO), the detected signal providing phase and intensity local information. The method includes correcting the phase computation according to intensity space variations. A wave front analyzer for implementing the method is also described.

Abstract: The invention relates, according to one aspect, to a retinal imaging device including at least one source (LSa, LSr) for emitting a light beam in order to illuminate the retina of an eye (10) of a subject, a retinal imaging path including a detection device (12) having a detection plane (121) and an optical imaging system (L1, L5, L6), an analysis path including a device (15) for measuring optical defects having an analysis plane (151) for receiving a set of light rays backscattered by the retina and optical means for adjoining said analysis plane and a predetermined plane in the input space of said imaging system of the imaging path, a correction device (14) shared by said analysis and imaging paths, which includes a correction plane (141) and which is intended to correct, in said correction plane, the light rays from said emission source and backscattered by the retina according to the optical defects measured by the device for measuring optical defects.

Abstract: An instrument (1) for characterizing an optical system, includes: at least one primary source (3) for emitting an illumination light beam (FE); an optical device for directing the illumination beam (FE) onto the optical system (L) to be characterized; a wave front analyzer (4) adapted for receiving a beam from the optical system (L); and a unit for processing the measure signals from the wave front analyzer (4), adapted for providing characterization information of the optical system (L). The instrument further includes a scattering member (22) substantially provided in the focal plane of the optical system (L) so as to create a secondary source generating a secondary beam flowing through the optical system (L) and further directed towards the wave front analyzer.

Abstract: The invention relates to a high-resolution retinal imaging method and device notably comprising an emission source (LSr) for emitting a light beam for the illumination of the retina of an eye (10) of a subject, a detection device (12) capable of detecting spatial-frequency structures of 250 cycles/mm measured in the plane of the retina, an optical imaging system (16) allowing for the formation of an image of at least a part of the retina on the detection device (12), a device (15) for measuring optical defects with an analysis plane of the optical defects, a correction device (14) comprising a correction plane and intended to correct, in said correction plane, the light rays from said emission source (LSr) and backscattered by the retina as a function of the optical defects measured by the measurement device (15).

Abstract: A phase modulation device implemented in an ophthalmic instrument using a main light beam interacting with an eye, the device including: an apparatus for modulating the phase of the wave front of the main light beam, a controller for controlling the phase modulation apparatus following a modulation instruction, and an analyzer for analyzing the thus-performed modulation of the phase of the wave front of the main light beam, further including emitting a secondary light beam, an apparatus for directing the secondary light beam along an optical path to the modulation apparatus, then to the analyzer, and in that the optical path does not pass through the eye, and in that the controller and the analyzer receiving the modulated secondary light beam cooperate, during a stage called a learning stage, to supply data regarding the response of the phase modulation apparatus to a set of predetermined modulation instructions.

Abstract: An instrument (1) for characterizing an optical system, includes: at least one primary source (3) for emitting an illumination light beam (FE); an optical device for directing the illumination beam (FE) onto the optical system (L) to be characterized; a wave front analyzer (4) adapted for receiving a beam from the optical system (L); and a unit for processing the measure signals from the wave front analyzer (4), adapted for providing characterization information of the optical system (L). The instrument further includes a scattering member (22) substantially provided in the focal plane of the optical system (L) so as to create a secondary source generating a secondary beam flowing through the optical system (L) and further directed towards the wave front analyzer.

Abstract: A method for correcting a wave front analyzer, in which the analyzer detects a signal from an incident wave front to be analyzed (FO), the detected signal providing phase and intensity local information. The method includes correcting the phase computation according to intensity space variations. A wave front analyzer for implementing the method is also described.

Abstract: A phase modulation device implemented in an ophthalmic instrument using a main light beam interacting with an eye, the device including: an apparatus for modulating the phase of the wave front of the main light beam, a controller for controlling the phase modulation apparatus following a modulation instruction, and an analyzer for analyzing the thus-performed modulation of the phase of the wave front of the main light beam, further including emitting a secondary light beam, an apparatus for directing the secondary light beam along an optical path to the modulation apparatus, then to the analyzer, and in that the optical path does not pass through the eye, and in that the controller and the analyzer receiving the modulated secondary light beam cooperate, during a stage called a learning stage, to supply data regarding the response of the phase modulation apparatus to a set of predetermined modulation instructions.

Abstract: Method for shielding a high-power laser apparatus (S) in which a laser beam is generated and then amplified in at least a first amplification stage, including spatial filtering (4) of the amplified laser beam, phase correction (3) carried out on the laser beam before it is spatially filtered, and a measurement of the aberrations (7) on the laser beam. The phase of the beam is corrected so as to produce a beam having minimal aberrations after spatial filtering. The shielding device (D, D?) implementing this method may in particular be employed in apparatus using an intense laser beam of high (terawatt) peak power and in proton therapy units.

Abstract: An autostereoscopic viewing device switchable between a two-dimensional mode and a three-dimensional mode. The device generally includes a matrix viewing display, and a set of two lenticular networks or arrays, one of which is called a converting lenticular network or array. The lenticular networks or arrays are arranged in front of the viewing display. The converting lenticular array is designed to receive and optically process a raster or matrix image emitted by the viewing display. The autostereoscopic viewing device further includes means for varying a plurality of distances between a first lenticular array and a second lenticular array or the viewing display. The invention is useful in particular for computer displays or three-dimensional television sets.

Abstract: An autostereoscopic display device comprises a matrix display screen having a horizontal axis and a vertical axis, and a lenticular array arranged in front of the display screen and having a lenticular axis that is inclined in relation to the vertical axis. The display device emits an image comprising a set of three-dimensional pixels, each three-dimensional pixel including a plurality of viewpoints of a corresponding image pixel of a scene to be displayed. For each three-dimensional pixel, the plurality of viewpoints of each corresponding image pixel are encoded along a horizontal axis, while color components associated with each viewpoint of each image pixel are encoded in separate rows generally aligned along an encoding axis that is substantially parallel to the lenticular axis.

Abstract: The invention relates to a method and to apparatus for contactlessly measuring the curvature of an ophthalmic article (1) having a “front” face (1B) that presents said curvature. The method consists in: sequentially emitting at least two light beams (L1, L2) onto said front face, these two light beams being offset by a certain angle (?) and converging substantially onto said front face, one of said emitted light beams (L1) being substantially centered on said front face and being substantially normal to said front face; analyzing the wave fronts of the resulting reflected beams (L?1, L?2) in order to determine their respective focuses (F1, F2) therefrom; and deducing the radius of curvature of said face; said operations being performed in such a manner that said emitted beams are substantially not reflected by the rear face of said article.

Abstract: The invention relates to a method and to apparatus for contactlessly measuring the curvature of an ophthalmic article (1) having a “front” face (1B) that presents said curvature. The method consists in: sequentially emitting at least two light beams (L1, L2) onto said front face, these two light beams being offset by a certain angle (?) and converging substantially onto said front face, one of said emitted light beams (L1) being substantially centered on said front face and being substantially normal to said front face; analyzing the wave fronts of the resulting reflected beams (L?1, L?2) in order to determine their respective focuses (F1, F2) therefrom; and deducing the radius of curvature of said face; said operations being performed in such a manner that said emitted beams are substantially not reflected by the rear face of said article.

Abstract: Device for measuring aberrations in an eye includes, an illumination path with an illumination diaphragm and a test path, imaging member and elements for positioning the eye in relation to the imaging member, a stray reflection filter element, which is centered on the measurement axis of the imaging member, and elements for the optical conjugation of the pupil of the eye with the plane of the illumination diaphragm and the test plane. The illumination beam path converges at the center of the filtration element. The filtration element, the illumination path, the test path and the conjugation elements are all interdependent and positioned on a platform that can move in relation to the imaging member along the axis. The illumination diaphragm is off-center in relation to the axis such that stray light flux reflected by the imaging member is deflected from the test path by filtration element.

Abstract: A device for automatically detecting characteristics of an ophthalmic lens includes a support receiving the lens, an illumination system and an analysis system. The optics of the illumination system define two alternate optical paths, one of which passes through a mask forming a Hartmann matrix.

Abstract: A method and device for measuring optical wavefront shape parameters based on line-by-line analysis of the wavefront are disclosed. The method comprises at least one step (ACQi) consisting of acquiring a wavefront line. The acquisition comprises detecting (DETi) the line for delivering an electric signal characterizing it, for example, by means of a detection module including, in particular, an array of microlenses and a sensor, the module capable of being mobile in rotation and/or in translation. The acquisition comprises a step (Tsi) for processing the signal for determining a set Ki of parameters, for example, values proportional to the wavefront phase values measured on the line. In an embodiment, the method further comprises a step (RECi) for reconstructing each wave line consisting, for example, in expressing the line phase on a base of orthogonal polynomials, then a step (RECs) for reconstructing the wavefront on the basis of the reconstructed lines.

Abstract: A device for automatically detecting characteristics of an ophthalmic lens includes a support receiving the lens, an illumination system and an analysis system. The optics of the illumination system define two alternate optical paths, one of which passes through a mask forming a Hartmann matrix.

Abstract: The invention concerns an optical device for the contactless measurement of the distance of a light source (4) comprising optical detecting means (7) consisting of elementary sensors and further comprising: a set of N imaging means (SP1, SP2, SP3), N≧3, that enable image acquisition of the light source on a plane in the proximity of the detecting means thereby forming with said means a set of hot spots, each spot spreading over at least two elementary sensors; a circuit for computing, on the basis of the relative positions of at least three hot spots, at least one characteristic parameter of the distance from the light source whereof the accuracy depends on N number of hot spots. The measuring device is characterized in that it is designed for industrial measurements (of dimensions, texture, position, vibrations, displacement).