Abstract: A system for imaging a scene, including an emitter configured to emit frequency-modulated continuous-wave laser radiation in a direction of propagation; an image sensor, including a set of photodetectors; an optical component, arranged to incorporate first and second splitting surfaces such that the first and second splitting surfaces intersect at right angles along a line of intersection perpendicular to the direction of propagation, and such that the first and second splitting surfaces are rotationally integral; a processor configured to process a heterodyne signal from each photodetector originating from a recombination of an object beam with a reference beam, so as to obtain a distance image of the scene.

Abstract: The present description concerns a pixel (PIX). A circuit (CIRC1) delivers, after each integration period corresponding to a period of transmission of a signal FMCW, first, second, third, and fourth signals (I, Q, Ic, Qc) representative of charges photogenerated in a photodetector (PD) during first, second, third, and fourth time periods, which are phase-shifted by ?/2 and repeated at an integration frequency (fs). A circuit (CIRC2) delivers a fifth signal (?c) determined by the difference of the first and third signals (I, Ic), and a sixth signal (QQc) determined by the difference of the second and third signals (Q, Qc). A circuit (CIRC3) compares the fifth and sixth signals (?c, QQc) with a first voltage determined by a positive threshold and a second voltage determined by a negative threshold.

Abstract: The invention relates to a reduced-size FMCW lidar imager system. The imager system comprises an optical source 10 for a coherent, continuous and frequency-modulated primary signal Sp in order to illuminate the scene 2; an optical collection element 41 configured to collect a backscattered signal Sret,c; a photodetector 50 intended to receive a heterodyne signal Sh associated with the collected signal Sret,c; and a processing unit 60 configured to determine the distance zsc from the scene based on a beat frequency of the heterodyne signal sh. It is configured to fully direct the primary signal Sp to the scene 2. It additionally comprises a reflector 42 configured to reflect a portion Spr,nc, called uncollected signal Sret,nc, of the backscattered signal Sret, not collected by the optical collection element 41, in the direction of the scene 2.

Abstract: The invention relates to a FMCW lidar imager system with improved distance resolution. The imager system 1 comprises a reflector 42 configured to reflect, in the direction of the scene 2, a portion Sor,nc of the backscattered object signal Sor, which portion has not been collected by the collecting optical element 41. Thus, the collected portion Sor,c of the backscattered object signal Sor is formed from first light beams Sor,c(1) that have not been reflected by the reflector 42 and from light beams Sor,c(2) that have been reflected by the reflector 42. The heterodyne signal Sh therefore has a principal component Sh(1) associated with the light beams Sor,c(1), and a secondary component Sh(2) associated with the light beams Sor,c(2). The processing unit 60 is configured to determine the distance zsc of the scene 2 on the basis of a beat frequency fb(2) of the secondary component Sh(2) of the heterodyne signal Sh.

Abstract: The invention relates to a LIDAR imaging system of the FMCW type, comprising a light source (10), an optical projection device (20), an optical transmission device (30), an optical imaging device (40), and a matrix photodetector (50). It further comprises a phase correction device (60) comprising a spatial phase modulator (61) for applying a corrected spatial phase distribution to the reference signal, and a computation unit (62) for determining the corrected spatial phase distribution, by taking into account a spatial distribution representing a spatial intensity distribution of the backscattered object signal, so that the reference signal has a corrected spatial intensity distribution in the reception plane optimizing a spatial distribution of a parameter of interest representing the heterodyne signal.

Abstract: A detection device for a coherent lidar imaging system includes an integrated detector comprising a matrix array of pixels distributed over N columns and M rows and comprising an optical guide, called reference guide, configured so as to receive a laser beam, called reference beam, N optical guides, called column guides, coupled to the reference guide, each column guide being coupled to M optical guides, called row guides, the M row guides being configured so as to route part of the reference beam into each pixel of the column, called pixel reference beam, each pixel of the integrated detector comprising: a guided photodiode coupled to an optical detection guide, a diffraction grating, called pixel grating, configured so as to couple a portion of a beam illuminating the pixel into the guided photodiode, a coupler, called pixel coupler, configured so as to couple the pixel coupled beam and at least a fraction of the pixel reference beam into the detection guide, an electronic readout and preprocessing circuit.

Abstract: A detection device for a coherent imaging system includes a detector comprising a matrix array of pixels, each pixel comprising a photodetector component having a photosensitive surface, the detector being designed to be illuminated by a coherent beam, called the image beam consisting of grains of light called speckle grains, a matrix array of transmissive deflecting elements configured to be individually orientable by means of an electrical signal, so as to deflect a fraction of the image beam incident on the group, and thus modify the spatial distribution of the speckle grains in the plane of the photosensitive surface, each group of one or more pixels further comprising a feedback loop associated with the deflecting element and configured to actuate the deflecting element so as to optimize the signal-to-noise ratio from the light detected by the one or more photodetector components of the group of pixels, the feedback loop comprising a feedback circuit.

Abstract: A continuous-wave lidar system includes a laser source configured to generate laser radiation (L) with a laser optical frequency fopt-I varying linearly over a plurality of N successive frequency ranges indexed i, a first optical device configured to spatially separate the laser radiation (L), a detecting device, a second optical device configured to simultaneously deliver, to the pixel, a recombined beam, a frequency shifter placed on the path of the reference beam and configured to shift the laser optical frequency by a shift frequency comprised in the interval [fRmax, fRmin], a processing unit, the continuous-wave lidar imaging system further being configured to determine distance information from a signal detected by the pixel.

Abstract: The present description concerns a method of acquisition of distances from a sensor to a scene, comprising a number N of consecutive capture sub-phases Ci, with N an integer greater than or equal to 2 and i an integer index ranging from 1 to N, each sub-phase Ci comprising: supplying a laser beam having an optical frequency (f) linearly varying over a frequency range of width Bi for a time period Ti; delivering, from the laser beam, a reference beam and a useful beam; and illuminating the scene with the useful beam and illuminating at least one pixel row with a superposition of the reference beam and of a reflected beam. An absolute value of a ratio Bi/Ti is different for each capture sub-phase Ci.

Abstract: The present description concerns an image sensor comprising a plurality of pixels (Pix), each comprising an elementary photodetector (211), wherein each pixel (Pix) comprises a circuit (201, 203) for detecting a beat frequency of a portion of a heterodyne beam received by the elementary photodetector (211) of the pixel, and wherein, in each pixel (Pix), the detection circuit (201, 203) comprises a frequency comparator (221) comprising a first input node (E1) receiving a first periodic AC signal (fpix) having a frequency equal to said beat frequency, a second input node (E2) receiving a second AC signal (framp) of variable frequency, and an output node (S) delivering an output signal switching from a first state to a second state when the frequency of the second signal (framp) exceeds the frequency of the first signal (fpix).

Abstract: The invention relates to a reduced-size FMCW lidar imager system. The imager system comprises an optical source 10 for a coherent, continuous and frequency-modulated primary signal Sp in order to illuminate the scene 2; an optical collection element 41 configured to collect a backscattered signal Sret,c; a photodetector 50 intended to receive a heterodyne signal Sh associated with the collected signal Sret,c; and a processing unit 60 configured to determine the distance zsc from the scene based on a beat frequency of the heterodyne signal sh. It is configured to fully direct the primary signal Sp to the scene 2. It additionally comprises a reflector 42 configured to reflect a portion Spr,nc, called uncollected signal Sret,nc, of the backscattered signal Sret, not collected by the optical collection element 41, in the direction of the scene 2.

Abstract: The invention relates to a FMCW lidar imager system with improved distance resolution. The imager system 1 comprises a reflector 42 configured to reflect, in the direction of the scene 2, a portion Sor,nc of the backscattered object signal Sor, which portion has not been collected by the collecting optical element 41. Thus, the collected portion Sor,c of the backscattered object signal Sor is formed from first light beams Sor,c(1) that have not been reflected by the reflector 42 and from light beams Sor,c(2) that have been reflected by the reflector 42. The heterodyne signal Sh therefore has a principal component Sh(1) associated with the light beams Sor,c(1), and a secondary component Sh(2) associated with the light beams Sor,c(2). The processing unit 60 is configured to determine the distance zsc of the scene 2 on the basis of a beat frequency fb(2) of the secondary component Sh(2) of the heterodyne signal Sh.

Abstract: The invention relates to a LIDAR imaging system of the FMCW type, comprising a light source (10), an optical projection device (20), an optical transmission device (30), an optical imaging device (40), and a matrix photodetector (50). It further comprises a phase correction device (60) comprising a spatial phase modulator (61) for applying a corrected spatial phase distribution to the reference signal, and a computation unit (62) for determining the corrected spatial phase distribution, by taking into account a spatial distribution representing a spatial intensity distribution of the backscattered object signal, so that the reference signal has a corrected spatial intensity distribution in the reception plane optimizing a spatial distribution of a parameter of interest representing the heterodyne signal.

Abstract: A coherent lidar imaging system includes a laser source, a detection device, a first optical device, an optical imaging system, a second optical device, the photodetector component of a pixel being configured so as to generate a pixel detected signal, the pixel detected signal having an intensity, called pixel total intensity, the splitter having a variable first transmittance that is identical for all of the pixels and modulable, the second optical device furthermore comprising at least one intensity modulator designed to modulate an intensity of each pixel reference beam by applying a modulable pixel transmittance, the coherent lidar imaging system furthermore comprising a processing unit configured so as to apply a first transmittance value and, for each pixel, a pixel transmittance value, the values being determined via a control loop and using an optimization criterion, the optimization criterion comprising obtaining, for each pixel, a pixel total intensity less than a threshold intensity, and obtaining

Abstract: A detection device for a coherent lidar imaging system includes an integrated detector comprising a matrix array of pixels distributed over N columns and M rows and comprising an optical guide, called reference guide, configured so as to receive a laser beam, called reference beam, N optical guides, called column guides, coupled to the reference guide, each column guide being coupled to M optical guides, called row guides, the M row guides being configured so as to route part of the reference beam into each pixel of the column, called pixel reference beam, each pixel of the integrated detector comprising: a guided photodiode coupled to an optical detection guide, a diffraction grating, called pixel grating, configured so as to couple a portion of a beam illuminating the pixel into the guided photodiode, a coupler, called pixel coupler, configured so as to couple the pixel coupled beam and at least a fraction of the pixel reference beam into the detection guide, an electronic readout and preprocessing circuit.

Abstract: A detection device for a coherent imaging system includes a detector comprising a matrix array of pixels, each pixel comprising a photodetector component having a photosensitive surface, the detector being designed to be illuminated by a coherent beam, called the image beam consisting of grains of light called speckle grains, a matrix array of transmissive deflecting elements configured to be individually orientable by means of an electrical signal, so as to deflect a fraction of the image beam incident on the group, and thus modify the spatial distribution of the speckle grains in the plane of the photosensitive surface, each group of one or more pixels further comprising a feedback loop associated with the deflecting element and configured to actuate the deflecting element so as to optimize the signal-to-noise ratio from the light detected by the one or more photodetector components of the group of pixels, the feedback loop comprising a feedback circuit.

Abstract: The invention relates to a directional lighting device (10) which comprises: a light emission source (30); a cover (40) covering the light emission source (30), and provided with an inner wall (41) and an outer wall (42) which delimit an inter-wall space (44), and filled with a fluid, the cover (40) comprising transmission zones (45), each formed of an inner zone (45a) and an outer zone (45b), facing one another, and at which an electric field is capable of being applied to the functional fluid by means of a first electrode (46a) and a second electrode (46b), the functional fluid being adapted to, under the effect of an electric field sensed at a given transmission zone, form with the latter a window transparent to the luminous radiation, and be either opaque or reflective and/or diffusive to said radiation in the remainder of the inter-wall volume (43).

Abstract: A method of adapting light extraction LEE from at least one light emitting diode with surface area S and perimeter P includes a step to encapsulate the light emitting diode with an encapsulation layer with a refraction index N, the refraction index N being determined based on a model taking account of an internal quantum efficiency of the light emitting diode. The extraction of light resulting from use of the encapsulation layer is such that the light emitting diode can achieve a predetermined external quantum efficiency.

Abstract: The invention relates to a directional lighting device (10) which comprises: a light emission source (30); a cover (40) covering the light emission source (30), and provided with an inner wall (41) and an outer wall (42) which delimit an inter-wall space (44), and filled with a fluid, the cover (40) comprising transmission zones (45), each formed of an inner zone (45a) and an outer zone (45b), facing one another, and at which an electric field is capable of being applied to the functional fluid by means of a first electrode (46a) and a second electrode (46b), the functional fluid being adapted to, under the effect of an electric field sensed at a given transmission zone, form with the latter a window transparent to the luminous radiation, and be either opaque or reflective and/or diffusive to said radiation in the remainder of the inter-wall volume (43).

Abstract: A photoresistor comprises two electrodes connected by a photosensitive layer of the photoresistor, and at least one additional layer which is in contact with the photosensitive layer in order to influence the behavior of the photoresistor regarding carrier collection between the two electrodes, in order to improve the sensitivity of the photoresistor.