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.

A time delay error occurring in the case of acquiring two holograms (object hologram and reference hologram) necessary for reconstruction in the related art or in the case of acquiring four physical holograms having different phase shift degrees may be removed. DC noise (including background noise) may be completely removed by using a software-implemented phase shifting method.

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.

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.

A differentiation system for differentiating cells includes an input device configured to receive holographic image data of a microscopic particle in suspension, holographic image data processing logic for converting the holographic image data to the frequency domain by performing a Fourier transform of the holographic image data, and a recognizer configured to determine characterization features of the holographic image data of the microscopic particle in the frequency domain for characterization of the microscopic particle, the characterization features comprising rotationally invariant features.

Provided are an improved holographic reconstruction apparatus and method.

A holographic reconstruction method includes: obtaining an object hologram of a measurement target object; generating a digital reference hologram calculated from the obtained object hologram; extracting each of a first phase information of the object hologram and a second phase information of the calculated digital reference hologram; calculating a phase information difference from the first phase information of the object hologram and the second phase information of the calculated digital reference hologram; and compensating for distorted phase information based on the calculated phase information difference, and calculating quantitative thickness information of the measurement target object by using the compensated distorted phase information to reconstruct 3-dimensional (3D) shape information and quantitative thickness information of the measurement target object.

Disclosed is a coherence-adjustable digital holography system. More particularly, the coherence-adjustable digital holography system includes a light source part for generating low-interference light; a dispersion part for dispersing the generated light, an adjustment part for adjusting coherence by adjusting a spectrum bandwidth of the light which has passed through the dispersion part; and a detection part for detecting a holographic image of a subject from the adjusted light. In accordance with such a configuration, an interference fringe may be easily obtained through coherence adjustment, whereby the accuracy of a detected holographic image may be improved.

An imaging device includes an image pixel array and a display pixel array. The image pixel array is configured to capture an infrared image of an interference between an infrared imaging signal and an infrared reference wavefront. The display pixel array is configured to generate an infrared holographic imaging signal according to a holographic pattern driven onto the display pixels. The holographic pattern is derived from the infrared image captured by the image pixel array.

An infrared image is captured by an image sensor and a frequency domain infrared image is generated by performing a Fourier transform operation on the infrared image. A filtered frequency domain infrared image is generated by applying a mask to the frequency domain infrared image. A spatial domain infrared image is generated by performing an inverse Fourier transform on the filtered frequency domain infrared image. Phase data is extracted from the spatial domain infrared image and a holographic pattern generated from the phase data is driven onto a display.

Example embodiments relate to imaging devices for in-line holographic imaging of objects. One embodiment includes an imaging device for in-line holographic imaging of an object. The imaging device includes a set of light sources configured to output light in confined illumination cones. The imaging device also includes an image sensor that includes a set of light-detecting elements. The set of light sources are configured to output light such that the confined illumination cones are arranged side-by-side and illuminate a specific part of the object. The image sensor is arranged such that the light-detecting elements detect a plurality of interference patterns. Each interference pattern is formed by diffracted light from the object originating from a single light source and undiffracted light from the same single light source. At least a subset of the set of light-detecting elements is arranged to detect light relating to not more than one interference pattern.