The present disclosure concerns an electron microscopy method, including the emission of a precessing electron beam and the acquisition, at least partly simultaneous, of an electron diffraction pattern and of intensity values of X rays.

A method for observing a sample, the sample lying in a sample plane defining radial positions, parameters of the sample being defined at each radial position, the method comprising: a) illuminating the sample using a light source, emitting an incident light wave that propagates toward the sample; b) acquiring, using an image sensor, an image of the sample, said image being formed in a detection plane, the sample being placed between the light source and the image sensor; c) processing the image acquired by the image sensor, so as to obtain an image of the sample, the image of the sample corresponding to a distribution of at least one parameter of the sample describing the sample in the sample plane; wherein the processing of the acquired image comprises implementing an iterative method, followed by applying a supervised machine learning algorithm, so as to obtain an initialization image intended to initialize the iterative method.

A method for lens-free imaging of a sample or objects within the sample uses multi-height iterative phase retrieval and rotational field transformations to perform wide FOV imaging of pathology samples with clinically comparable image quality to a benchtop lens-based microscope. The solution of the transport-of-intensity (TIE) equation is used as an initial guess in the phase recovery process to speed the image recovery process. The holographically reconstructed image can be digitally focused at any depth within the object FOV (after image capture) without the need for any focus adjustment, and is also digitally corrected for artifacts arising from uncontrolled tilting and height variations between the sample and sensor planes. In an alternative embodiment, a synthetic aperture approach is used with multi-angle iterative phase retrieval to perform wide FOV imaging of pathology samples and increase the effective numerical aperture of the image.

A method of generating a color image of a sample includes obtaining a plurality of low resolution holographic images of the sample using a color image sensor, the sample illuminated simultaneously by light from three or more distinct colors, wherein the illuminated sample casts sample holograms on the image sensor and wherein the plurality of low resolution holographic images are obtained by relative x, y, and z directional shifts between sample holograms and the image sensor. Pixel super-resolved holograms of the sample are generated at each of the three or more distinct colors. De-multiplexed holograms are generated from the pixel super-resolved holograms. Phase information is retrieved from the de-multiplexed holograms using a phase retrieval algorithm to obtain complex holograms. The complex hologram for the three or more distinct colors is digitally combined and back-propagated to a sample plane to generate the color image.

A device in holographic imaging comprises: at least two light sources, wherein each of the at least two light sources is arranged to output light of a unique wavelength; and at least one holographic optical element, wherein the at least two light sources and the at least one holographic optical element are arranged in relation to each other such that light from the at least two light sources incident on the at least one holographic optical element interacts with the at least one holographic optical element to form wavefronts of similar shape for light from the different light sources.

A device and a method for observing an object by imaging, or by lensless imaging. The object is retained by a holder defining an object plane inserted between a light source and an image sensor, with no enlargement optics being placed between the object and the image sensor. An optical system is arranged between the light source and the holder and is configured to form a convergent incident wave from a light wave emitted by the light source, and for forming a secondary light source, conjugated with the light source, positioned in a half-space defined by the object plane and including the image sensor, such that the secondary source is closer to the image sensor than to the holder. This results in an image with a transversal enlargement factor having an absolute value of less than 1.

Method for observing a sample comprising the steps of (a) illuminating the sample using a light source, the light source emitting an incident light wave that propagates toward the sample along a propagation axis (Z); (b) acquiring, using an image sensor, an image of the sample, which image is formed in a detection plane; (c) forming a stack of images, called reconstructed images, from the image acquired in step (b), each reconstructed image being obtained by applying, for one reconstruction distance, a numerical propagation operator; and (d) from each image of the stack of images, computing a clearness indicator for various radial positions, each clearness indicator being associated with one radial position and with one reconstruction distance.

A method of calibration of a device for analyzing at least one element present in a sample, said device including: a detection assembly configured to acquire an image formed by the interference between a light source and said sample; and digital processing means configured to detect a digital position of at least one element in said sample based on said acquired image; said calibration method including the implementation of a plurality of predetermined displacements of said sample with respect to said detection assembly and, for all of said displacements, the detection of a digital position of a same element to determine the digital position and the real position matching model according to the predetermined displacements and to the digital positions of said element after each displacement.

Methods and systems for generating a high-color-fidelity and high-resolution color image of a sample are disclosed; which fuses or merges a holographic image acquired at a single wavelength with a color-calibrated image taken by a low-magnification lens-based microscope using a wavelet transform based colorization method. A holographic microscope is used to obtain holographic images which are used to computationally reconstruct a high-resolution mono-color holographic image of the sample. A lens-based microscope is used to obtain low resolution color images. A discrete wavelet transform (DWT) is used to generate a final image that merges the low-resolution components from the lens-based color image and the high-resolution components from the high-resolution mono-color holographic image.

A device for acquisition of particles present in a sample includes a spatially coherent light source, an optical system, and an image sensor placed in the focal plane of the optical system. The image sensor is configured to capture an intensity image. A computational unit of the device is configured to construct a series of electromagnetic propagation matrices obtained for a plurality of defocusing offsets relative to a plane of focus of the optics. The computational unit is also configured to determine a first average focused electromagnetic matrix for the particles from the series of electromagnetic matrices, identifying at least one of the particles in the first electromagnetic matrix and storing the coordinates of said particle, and determining a second electromagnetic matrix at a distance of focus on a particle identified from the components of the series of electromagnetic matrices having the stored coordinates.