Abstract: A DEVICE FOR MULTI-PLANE CONVERSION OF A FIRST LIGHT RADIATION, HAVING A CONVERSION BLOCK COMPRISING A PLURALITY OF OPTICAL PARTS AND IMPLEMENTING A PLURALITY OF PHASE MASKS TO APPLY A SPATIOFREQUENTIAL PHASE SHIFT FOR PRODUCING A SECOND LIGHT RADIATION—A PREDETERMINED TRANSFORMATION, KNOWN AS A TRANSFORMATION WITH SEPARABLE VARIABLES. THE PREDETERMINED TRANSFORMATION MAY LINK N MODES OF INDEX {I, J}K, 1<=K<=N, OF A FIRST USED MODE FAMILY WITH SEPARABLE SPATIAL VARIABLES (X,Y) DESCRIBING THE FIRST LIGHT RADIATION IN A FIRST TRANSVERSE PLANE WITH N MODES OF THE SAME INDEX {I, J}K 1<=K<=N, OF A SECOND USED MODE FAMILY WITH SEPARABLE SPATIAL VARIABLES (X,Y) DESCRIBING THE SECOND LIGHT RADIATION AT A SECOND TRANSVERSE PLANE. THE N MODES OF THE SECOND MODE FAMILY ARE NOT BE HERMITE-GAUSSIAN MODES. THE N MODES OF THE FIRST MODE FAMILY ARE NOT ARRANGED ON THE FIRST TRANSVERSE PLANE IN THE FORM OF A TRIANGLE.

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 light source comprising: —at least one semiconductor chip capable of emitting incident radiation: —an output stage comprising at least one fiber or free space for propagating a plurality of predefined modes; —at least one optical part having a microstructured main surface arranged opposite the semiconductor chip for intercepting the incident radiation, spatially modifying the phase of the incident radiation and forming, by a plurality of reflections and/or transmissions on the optical component, transformed light radiation comprising at least the predefined modes.

Abstract: Device (1) for processing light radiation, comprising: —an optical input (2) for receiving an input beam from an optical source (3) and for propagating in the device (1) an input radiation, an optical output (4) for emitting an output beam having predetermined spatial parameters, an MPLC conversion device (5) which is arranged between the optical input (2) and the optical output (4) and which is configured to spatially separate, in a separation plane (7), the input radiation into useful radiation, in a target mode, which is propagated to the optical output (4) and into an interference radiation. The processing device also comprises at least one device (8) for blocking the interference radiation, which blocking device is arranged in the separation plane (7) so that it does not contribute to the output beam.

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 for forming an output light beam having at least one target mode, by combining a plurality of phase-locked input light beams collectively forming incident light radiation, comprises a conversion device, arranged between the input plane and the output plane, configured to carry out a modal conversion aimed at conveying the energy portion of incident radiation present in a main supermode to the target mode, and aimed at conveying the energy portion of the incident radiation present in interference supermodes to deformation modes. A system for producing an output light beam comprises such an optical device.

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 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: A method of stabilizing the distance (L) between two mirrors (3, 4) of an optical cavity (2). The method includes the steps of injecting into the cavity an incident light beam in the form of a comb of frequencies; observing the spectrum of the light emitted or reflected by the cavity by using a photodiode having at least two sensitive zones that are arranged relative to the emitted or reflected light in such a manner that when the spectrum is centered, the two sensitive zones of the photodiode are illuminated equally; and modifying the distance between the mirrors of the cavity so as to cancel any offset of the spectrum relative to a situation in which the spectrum is centered.