Abstract: A method for designing a device for multi-plane conversion of light radiation, the device implementing a plurality M of phase masks intercepting the light radiation in order to phase-shift the radiation for applying a predetermined transformation to the light radiation. First and second mode families (u,v) with separable variables (x,y) are defined. A number N of pairs of indices {i,j}k is chosen to form first and second used mode families, respectively, by selecting the modes of index pairs {i,j}k from the first mode family and from the second mode family, respectively. Next, the phase-shift quantities ?1(x,y) are established, the M phase masks making it possible to transform each mode of index pairs {i,j)k of the first used mode family into the mode of the same index pair {i,j}k of the second used mode family. A phase plate may be obtained by means of the design method and used in a multi-plane conversion device.

Abstract: A multi-passage cavity made up of the assembly of a planar mounting and first and second reflective optical elements each having a main face arranged opposite one another, the main face of at least one of the optical elements being microstructured to modify the phase of incident luminous radiation that is reflected several times on each of the optical elements to form transformed radiation, the multi-passage cavity includes precisely three assembly interfaces.

Abstract: A device for manipulating a light radiation by reflecting the light radiation multiple times on at least two reflecting surfaces of a monolithic block made of homogenous transparent material comprises a first and second zone on surfaces of the block for injecting the light radiation to be manipulated, and for extracting the light radiation after manipulation. At least one of the reflective surfaces is micro-structured to impart a determined spatial phase transformation.

Abstract: A device for alternating between different shapes of a light beam includes a multi-plane light conversion (MPLC) device that is used to apply a unitary transformation to a light beam by way of a succession of elementary transformations. The MPLC faces the light source so that the light beam is emitted into the MPLC device along a reference axis. The device further includes automated means arranged upstream of the multi-plane light conversion (MPLC) device for varying the transverse position and/or the angle of incidence of the light beam in relation to the reference axis and/or to vary the angle of rotation of the light beam about the reference axis. The MPLC device is designed to transform a variation of the transverse position and/or the angle of incidence and/or the angle of rotation of the light beam into a modification of the specific shape of the light beam.

Abstract: An optical device is formed of a plurality of optical parts arranged on a carrier, at least one optical element of which has a main face provided with a first microstructured zone for intercepting incident luminous radiation propagating along a first determined optical path, the first microstructured zone spatially modifying the phase of the incident luminous radiation according to a determined spatial profile. The first microstructured zone is used to form, via a plurality of reflections or transmissions off/through the one or more optical elements, transformed luminous radiation. The optical device comprises an input stage for guiding the injection of positioning luminous radiation, along a second optical path, and the main surface of the optical element includes a second microstructured zone that is configured to reflect the positioning luminous radiation and to back-propagate the positioning radiation along the second optical path.

Abstract: A method for fixing a single-mode fiber to a multimode fiber comprises the following steps: injecting light radiation into the injection end of the single-mode fiber and positioning the junction ends of the single-mode fiber and of the multimode fiber relative to one another so as to propagate at least part of the light radiation in the multimode fiber; modally decomposing the light radiation collected at the injection end of the multimode fiber and measuring a quantity representative of the optical power present in a first group of secondary modes; and adjusting the relative position of the junction ends and freezing them with respect to one another in a determined relative coupling position. Coupling equipment for carrying out the fixing method is also disclosed.

Abstract: A method for designing a device for multi-plane conversion of light radiation, the device implementing a plurality M of phase masks intercepting the light radiation in order to phase-shift the radiation for applying a predetermined transformation to the light radiation. First and second mode families (u,v) with separable variables (x,y) are defined. A number N of pairs of indices {i,j}k is chosen to form first and second used mode families, respectively, by selecting the modes of index pairs {i,j}k from the first mode family and from the second mode family, respectively. Next, the phase-shift quantities ?(x,y) are established, the M phase masks making it possible to transform each mode of index pairs {i,j)k of the first used mode family into the mode of the same index pair {i,j}k of the second used mode family. A phase plate may be obtained by means of the design method and used in a multi-plane conversion device.

Abstract: A device is provided for processing a light/optical radiation including at least two reflective optical elements defining a multi-pass cavity so that at least one of the optical elements reflects the light radiation at least twice, at at least two different reflection positions, and including at least one element, called a corrective element, having at least one position, called a corrective position, producing a reflection or a transmission of the optical radiation, and the surface of which is irregular so that the spatial phase profile of the corrective position has a different phase shift for several different reflection/transmission points of the corrective position.

Abstract: An optical phase-shifting component is used for shifting the phase and modifying the intensity of the light beam injected into the fiber (MMF2). The component is inserted upstream or downstream of, or at an intermediate position in, the fiber. The component uses two mirrors and multiple beam paths between the mirrors. An optical phase-shifting structure (e.g., a reflective phase mask with a structured surface, which can be a mirror) is effective at each reflection of the beam and gradually splits the beam into faster and slower propagation modes. The faster modes are subjected to one or more reflections more than the slower modes and are thereby decelerated. The fast and slow modes are combined again and are then transmitted in a multimode fiber in which the modes have different propagation speeds. The difference in the propagation speeds is thus at least partly compensated.

Abstract: A device is provided for processing a light/optical radiation including at least two reflective optical elements defining a multi-pass cavity so that at least one of the optical elements reflects the light radiation at least twice, at at least two different reflection positions, and including at least one element, called a corrective element, having at least one position, called a corrective position, producing a reflection or a transmission of the optical radiation, and the surface of which is irregular so that the spatial phase profile of the corrective position has a different phase shift for several different reflection/transmission points of the corrective position.

Abstract: A method and a system is provided for configuring a device for correcting the effect of a medium on a light signal having propagated through the medium, the device including at least one optical element whose phase profiles are individually adjustable. The configuring system and method include propagating a reference signal and a disordered signal obtained at the output of the medium through the correcting device. An interference parameter is measured and optimized by modifying the phase profile of each of the optical elements of the correcting device. A method and a system is also provided for correcting the effect of a medium on a light signal having propagated through the medium.