The inventive concept relates to a device for detecting particles in air, said device comprising a receiver for receiving a flow of air comprising particles, a sample carrier, and a particle capturing arrangement. The particle capturing arrangement is configured to separate the particles from the flow of air for and to collect a set of particles on a surface of the sample carrier. The device further comprises a light source configured to illuminate the particles on the sample carrier, such that an interference pattern is formed by interference between light being scattered by the particles and non-scattered light from the light source. The device further comprises an image sensor configured to detect the interference pattern. The device further comprises a cleaner configured for cleaning the surface of the sample carrier for enabling re-use of the surface for collection of a subsequent set of particles.

A system for analyzing a transparent particle including: an analysis pathway, including a first light source emitting an analysis light beam, and a first optical system focusing the analysis light beam in a focusing plane; and a position control pathway including a second light source, an image sensor, and a second optical system at least partially merged with the first optical system. The image sensor is offset relative to the image of the focusing plane by the second optical system. The system makes it possible to control correct positioning of the particle, even though it is transparent, and without disturbing the analysis pathway.

The invention concerns a method for identifying biological particles from a stack of holographic images obtained by means of an optical system. A stack of image blocks centred on the biological particle to be analysed is extracted from the stack of images and a reference block corresponding to the focus plan is determined. A characteristic magnitude is calculated for each block of the stack and the profile of this characteristic magnitude along the optical axis of the system is compared with a plurality of standard profiles relative to known types of particle. Alternatively, blocks of the stack are extracted from the stack of blocks for predetermined defocusing deviations and the extracted blocks are compared with standard blocks relative to known types of particle.

Systems and methods for sub-aperture correlation based wavefront measurement in a thick sample and correction as a post processing technique for interferometric imaging to achieve near diffraction limited resolution are described. Theory, simulation and experimental results are presented for the case of full field interference microscopy. The inventive technique can be applied to any coherent interferometric imaging technique and does not require knowledge of any system parameters. In one embodiment of the present application, a fast and simple way to correct for defocus aberration is described. A variety of applications for the method are presented.

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 extracting particles from a two-dimensional (2D) hologram recorded as part of a digital inline holography system includes reconstructing a three-dimensional (3D) optical field from the recorded 2D hologram. In addition, particles are extracted/segmented from the 3D optical field, wherein segmented particles are identified by particle location in three-dimensional space and a cross-sectional area of the segmented particle. Based on the identified particle location and cross-sectional area, extracted particles are removed from the 2D hologram to generate an updated 2D hologram. These steps are repeated iteratively until a threshold is met.

At least one embodiment relates to an autofocus method for determining a focal plane for at least one object. The method includes reconstructing a holographic image of the at least one object such as to provide a reconstructed image at a plurality of different focal depths. The reconstructed image includes a real component and an imaginary component. The method also include performing a first edge detection on the real component for at least two depths of the plurality of different focal depths and a second edge detection on the imaginary component for the at least two depths. Further, the method includes obtaining a first measure of clarity for each of the at least two depths based on a first measure of statistical dispersion with respect to the first edge detection and a second measure of clarity.

A method of analyzing a sample receiving a particle of interest, including: defining a reference point located on a first interface of the sample, or at a known distance from the sample, along the optical axis of the optical system; acquiring a reference image transmission of the sample, the object plane of the optical system being located at a known distance from the reference point along an axis parallel to the optical axis of the optical system, and the particle of interest being located outside of the object plane; using the reference image, digitally constructing a series of reconstructed images, each associated with a predetermined offset of the object plane along the optical axis of the optical system; and using the series of reconstructed images, determining the distance along an axis parallel to the optical axis of the optical system, between the particle of interest and the reference point.

Provided are holographic displays and operating methods of the holographic display. The holographic display includes a backlight portion configured to emit light for displaying an image; a deflector configured to control a direction at which the image is displayed; a lens portion configured to control a location where the image to be displayed is formed to match a location that satisfies a diffraction condition; and a panel portion configured to display a 3D image by combining the image to be displayed with an interference pattern generated with respect to an overlapped hologram.

A device for detecting at least one object present in a sample, the device including a light source to emit at least one incident wave at a wavelength λ, a detection volume intended to receive the object, and to receive at least one incident wave, an image sensor positioned to receive at least one scattered light wave obtained by diffraction of the incident wave on the object and a reference wave from the source and not diffracted on the object and to generate a holographic image, and a computer data processing device to digitally reconstruct the object based at least on the holographic image and the wavelength λ. The device also comprises a support comprising patterns organized to form at least one diffraction grating, the grating being periodic and having a pitch P, such that λ/2≤P≤2λ.