Abstract: There is described a method for making an array of micro-needles, comprising the steps of: depositing a plurality of drops of a liquid substance comprising a polymer on a surface of a starting substrate; positioning a pyroelectric substrate at a certain distance from the starting substrate in such a way that the drops deposited are positioned between said surface of the starting substrate and a surface of the pyroelectric substrate; varying the temperature of the pyroelectric substrate or a part thereof to induce on said surface of the pyroelectric substrate a charge density such that starting from the drops deposited, under the effect of an electrodynamic force, respective cones are formed having a tip facing towards the pyroelectric substrate; determining a consolidation of the cones, to form said micro-needles, preventing the tip of said cones from contacting said surfaces of the pyroelectric substrate.

Abstract: Disclosed a system for reconstructing an image of an object hidden by a flame. The system comprises a laser source emitting an infrared radiation and a lensless, off-axis interferometric arrangement that divides the infrared radiation into an object beam and a reference beam. The object beam is enlarged and then irradiates the object, that scatters it. The reference beam is enlarged and then interferes with the scattered object beam, so as to create a hologram. The system comprises an infrared detector which detects the hologram and a processor that reconstructs the image of the object by numerically processing the hologram.

Abstract: There is described a method for making an array of micro-needles, comprising the steps of: depositing a plurality of drops of a liquid substance comprising a polymer on a surface of a starting substrate; positioning a pyroelectric substrate at a certain distance from the starting substrate in such a way that the drops deposited are positioned between said surface of the starting substrate and a surface of the pyroelectric substrate; varying the temperature of the pyroelectric substrate or a part thereof to induce on said surface of the pyroelectric substrate a charge density such that starting from the drops deposited, under the effect of an electrodynamic force, respective cones are formed having a tip facing towards the pyroelectric substrate; determining a consolidation of the cones, to form said micro-needles, preventing the tip of said cones from contacting said surfaces of the pyroelectric substrate.

Abstract: It is disclosed a system for reconstructing an image of an object hidden by a flame. The system comprises a laser source emitting an infrared radiation and a lensless, off-axis interferometric arrangement that divides the infrared radiation into an object beam and a reference beam. The object beam is enlarged and then irradiates the object, that scatters it. The reference beam is enlarged and then interferes with the scattered object beam, so as to create a hologram. The system comprises an infrared detector which detects the hologram and a processing unit which reconstructs the image of the object by numerically processing the hologram. The system therefore provides the object image based on digital holography at infrared wavelengths. Differently from known thermographic acquisition techniques, even if large portions of the object are hidden by the flame, the system allows to reconstruct an image of the whole object, with no blind areas.

Abstract: The invention concerns a method for controlling depth-of-focus in 3D image reconstructions, in particular for: A) Controlling the focus with the aim to synthesize a holography dynamic 3D scene; such a scene can be either numerically reconstructed or holographically projected for 3D display purposes by means of optical reconstruction through Spatial Light Modulator (SLM); B) controlling the focus to extend the depth of focus and have two object at different distance simultaneously in focus by digital holography; The method according to the invention can be applied with few differences both to the usual holograms and to the Fourier ones.

Abstract: The invention concerns a holographic method with numerical reconstruction for obtaining an image of a three-dimensional object, said method employing a digitalised hologram of an object, and comprising a step A. wherein, starting from the digitalised hologram, extracting a phase image of said object corresponding to a bidimensional matrix MD of distance values; a step B. wherein a mono-dimensional subassembly SD of the distance value assembly present in matrix MD of the method step A is selected, subassembly SD containing distance values dk; a step C. wherein for each distance value dk, extracting from matrix MD a iso-level assembly IQdk corresponding to a mono-dimensional assembly of bidimensional coordinates of said object, a step D. wherein for each distance value dk, reconstructing, starting from the digitalised hologram, a bidimensional matrix IMdk of intensity values relevant to said object; a step E.

Abstract: The invention concerns a quantitative phase-contrast digital holography method for the numerical reconstruction of images, comprising the following steps: A. acquiring a digital hologram of an investigated object; B. reconstructing the digital hologram in a reconstruction plane; C. reconstructing the complex field for the digital hologram; D. obtaining the phase map starting from the complex field; the method being characterised in that it further comprises the following steps: E. applying to the digital matrix of any step A, B, C a shear sx and/or sy respectively along directions x and/or y; F. subtracting the matrix obtained in step E from the starting matrix of step E, or vice versa; G. integrating the obtained matrix along directions x and/or y; H. calculating at least a defocus aberration term; I. subtracting said at least a term calculated in step H from the matrix obtained in step G, the steps G to I being subsequent to step D.

Abstract: A method for measuring and two-dimensional mapping of electro-optical properties of materials using a Reflective Grating Interferometer (RGI) includes projecting a substantially coherent and monochromatic electromagnetic beam subjected to a homogeneous electrical field so the beam is enlarged to have a two-dimensional cross section comparable with dimensions of the material, dividing the electromagnetic beam into one part that crosses the material and another part that travels undisturbed, recomposing the two beams on a recombination element of the RGI, detecting the recombined beam by a device suited to two-dimensional detection of such beam. The method also includes: E. obtaining phase variation ?ø(x,y) between the divided beams; F. varying the applied electrical field value and repeating the detection steps; G.

Abstract: A holographic method with numerical reconstruction for obtaining an image of a three-dimensional object, employs a digitalized hologram of an object or of a portion thereof, and includes starting from the digitalized hologram, extracting a phase image of the object corresponding to a matrix MD of distance values, selecting a subassembly SD of the distance value assembly present in matrix MD, subassembly SD containing distance values dk, extracting from matrix MD an iso-level assembly IQdk of corresponding bidimensional coordinate of the object; reconstructing, for each distance value dk, a bidimensional matrix IMdk of intensity values relevant to the object; extracting, from each bidimensional matrix IMdk, a bidimensional IFdk of intensity values; and starting from the intensity values, reconstructing the three-dimensional intensity image of the object.

Abstract: A holographic method with numerical reconstruction for obtaining an image of a three-dimensional object, employs a digitalized hologram of an object or of a portion thereof, and includes starting from the digitalized hologram, extracting a phase image of the object corresponding to a matrix MD of distance values, selecting a subassembly SD of the distance value assembly present in matrix MD, subassembly SD containing distance values dk, extracting from matrix MD an iso-level assembly IQdk of corresponding bidimensional coordinate of the object; reconstructing, for each distance value dk, a bidimensional matrix IMdk of intensity values relevant to the object; extracting, from each bidimensional matrix IMdk, a bidimensional IFdk of intensity values; and starting from the intensity values, reconstructing the three-dimensional intensity image of the object.

Abstract: The invention concerns a method Method for the reconstruction of holographic images, the holographic image being detected by an image detection device (9), the holographic image being transformed in a digitized hologram (10), the digitized hologram (10) being comprised of a number Vr of elementary pixels, the size of which being equal to the holographic image sampling intervals, and of the Vr values (51) respectively associated to the elementary pixels, the method comprising a first step (11,12) of processing the digitized hologram array, and a second step (13,15,16,17,18) of hologram reconstruction in the observation plane starting from the digitized hologram processed in the first step, the method being characterised in that the second step is carried out through discrete Fresnel Transform applied on an array of Ve values corresponding to pixels having size equal to that of said elementary pixels, wherein said array of Ve values (50, 51) includes said array of Vr values and an integer number p=Ve?Vr>0 of