In order to quantitatively characterize biological objects, for example individual cells, a stimulus is applied to a biological object (8) in a contactless fashion. A measurement and a further measurement are performed on the biological object (8) in order to ascertain a response of the biological object (8) to the stimulus, wherein the measurement and the further measurement comprise detecting Raman scattering on and/or in the biological object (8) and/or capturing data using digital holographic microinterferometry (DHMI). The biological object (8) is characterized according to a result of the measurement and is sorted if needed. The stimulus can be applied by means of a laser beam that creates optical tweezers or an optical trap, by means of ultrasonic waves or an electric or magnetic radio frequency field.

A dark field digital holographic microscope is disclosed which is configured to determine a characteristic of interest of a structure. The dark field digital holographic microscope comprises an illumination device configured to provide at least: a first beam pair comprising a first illumination beam of radiation (1010) and a first reference beam of radiation (1030) and a second beam pair comprising a second illumination beam of radiation (1020) and a second reference beam of radiation (1040); and one or more optical elements (1070) operable to capture a first scattered radiation and to capture a second scattered radiation scattered by the structure resultant from the first and second illumination beams respectively. The beams of the first beam pair are mutually coherent and the beams of the second beam pair are mutually coherent. The illumination device is configured to impose incoherence (ADI) between the first beam pair and second beam pair.

A method for analyzing microorganisms arranged in a sample is provided, the sample including a viability marker to modify an optical property of the microorganisms in different ways depending on whether they are dead or alive, the method including illumination of the sample and acquisition of an image of the latter by an image sensor, the image sensor then being exposed to an exposure light wave; determining positions of different microorganisms from the acquired image; applying a propagation operator to calculate at least one characteristic value of the exposure light wave at each radial position and at a plurality of distances from the detection plane representing a change in the characteristic value between the image sensor and the sample; and identifying living microorganisms according to each profile.

According to an aspect of the present inventive concept there is provided an imaging system for imaging of a sample, comprising a light source, an interference filter and a detector, the light source generates illumination light of a single wavelength to induce elastic scattering of the light by the sample, the interference filter selectively reduces transmittance of light having an incident angle on the interference filter corresponding to non-scattered light, the detector is configured to detect a two-dimensional representation of the elastically scattered light transmitted by the interference filter.

A method for observing a sample (10), the sample lying in a plane of the sample defining radial coordinates, the method comprising the following steps: a) illuminating the sample using a light source (11), able to emit an incident light wave (12) that propagates toward the sample along a propagation axis (Z); b) acquiring, using an image sensor (16), an image (I.sub.0) of the sample (10), said image being formed in a detection plane (P.sub.0), the sample being placed between the light source (11) and the image sensor (16), such that the incident light wave sees an optical path difference, parallel to the propagation axis (Z), by passing through the sample; c) processing the image acquired by the image sensor;
wherein the processing of the acquired image comprises taking into account vectors of parameters, respectively defined at a plurality of radial coordinates, in the plane of the sample, each vector of parameters being associated with one radial coordinate, and comprising a term representative of an optical parameter of the sample, at least one optical parameter being an optical path difference induced by the sample at the radial coordinate, the vectors of parameters describing the sample.

An apparatus and method to produce a hologram of an object includes an electromagnetic radiation assembly configured to receive a received electromagnetic radiation, such as light, from the object. The electromagnetic radiation assembly is further configured to diffract the received electromagnetic radiation and transmit a diffracted electromagnetic radiation. An image capture assembly is configured to capture an image of the diffracted electromagnetic radiation and produce the hologram of the object from the captured image.

A system for monitoring a building structure is described. The system comprises a laser source which emits an infrared radiation and an interferometric arrangement which divides the radiation into an object beam and a reference beam. The object beam irradiates the building structure and is scattered by it, while the reference beam interferes with the scattered object beam so as to create a hologram of the building. The system also comprises a sensor which detects a sequence of holograms and a processing unit which reconstructs the evolution in time of deformations or displacements of the building by numerically processing the sequence of holograms. The system—being based on digital holography—offers various advantages compared to known monitoring techniques, for example techniques which make use of seismometers (possibility of remote monitoring, substantial space-time continuity of the monitoring, capacity for detecting a wider range of deformations and displacements).

Embodiments described herein relate to a large area lens-free imaging device. One example is a lens-free device for imaging one or more objects. The lens-free device includes a light source positioned for illuminating at least one object. The lens-free device also includes a detector positioned for recording interference patterns of the illuminated at least one object. The light source includes a plurality of light emitters that are positioned and configured to create a controlled light wavefront for performing lens-free imaging.

Both a hologram and fluorescence are simultaneously captured in a state in which they can be reconstructed separately. A recording device (10) includes: a laser light source (LS1) which irradiates a subject (13) with object illumination light so that object light is generated; and an image capturing device (12) which captures (i) a hologram formed by interference between reference light and object light and (ii) an image of fluorescence, and the object illumination light further excites a fluorescent material (14) contained in the subject (13).

A focus adjustment method for acquiring an image of a surface of interest of a sample by a holographic imager includes the steps of: placing the sample including at least one reference object having a known shape and described by characterising parameters having at least position parameters acquiring an image and determining the position of the reference object with respect to the acquisition plane, by applying a light diffraction model involving the spatial parameters of the reference object estimated by approximating the appearance of the reference object in the holographic image acquired, and determining the position of the surface of interest with respect to the acquisition plane from a position of the reference object and focus adjustment of the image acquisition.