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 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).

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).

According to an embodiment, a holographic microscope comprises a light source emitting light to an object, a beam splitter reflecting the light emitted from the light source to the object and transmitting object light reflected from the object, a holographic image sensor sensing information, including a holographic image, by receiving the object light and allowing the object light to coherently interfere with reference light, and an image processor obtaining three-dimensional (3D) information about the object based on the information sensed by the holographic image sensor. The holographic image sensor includes a lens focusing the object light to the holographic image sensor, a filter transmitting a predetermined wavelength band of light of the focused object light, a light receiving unit receiving interference light to sense a holographic image, and a reference light source directly emitting the reference light having the predetermined wavelength band to the light receiving unit.

The present invention relates to a system and method for digital holographic microscopy. According to an aspect of the invention there is provided an off-axis digital holographic microscope comprising: a light emitter configured to provide a divergent light beam; a sensor position to receive light from the light emitter in a first path and a second path, and thereby to detect a holographic image; a reflector positioned partially in the divergent light beam so that light that encounters the reflector extends towards the sensor in the first path, and light that does not encounter the reflector extends towards the sensor in the second path; and a support structure configured to support a sample in the first path or the second path.

A device and method for measuring a surface of an object, including at least one light source, at least one optical sensor, and an interferometry device having a measurement arm and a reference arm, the former directing light from each light source towards the surface of the object and directing light from the surface towards each optical sensor; the measurement device, in an interferometry configuration, illuminating the reference arm and the measurement arm with each light source and directing the light from the measurement arm and the reference arm towards each optical sensor to form an interference signal; the measurement device, in an imaging configuration illuminating at least the measurement arm and directing the light from the measurement arm towards the optical sensor to form an image of the surface; the measurement device including a digital processor producing, from the interference signal and the image, information on the surface.

An optical measurement system comprises a polarization beam splitter for dividing an incident beam into a reference beam and a measurement beam, a first beam splitter for reflecting the measurement beam to form a first reflected measurement beam, a spatial light modulator for modulating the first reflected measurement beam to form a modulated measurement beam, a condenser lens for focusing the modulated measurement beam to an object to form a penetrating measurement beam, an objective lens for converting the penetrating measurement beam into a parallel measurement beam, a mirror for reflecting the parallel measurement beam to form an object beam, a second beam splitter for reflecting the reference beam to a path coincident with that of the object beam, and a camera for receiving an interference signal generated by the reference beam and the object beam to generate an image of the object.

An imaging flow cytometer device includes a housing holding a multi-color illumination source configured for pulsed or continuous wave operation. A microfluidic channel is disposed in the housing and is fluidically coupled to a source of fluid containing objects that flow through the microfluidic channel. A color image sensor is disposed adjacent to the microfluidic channel and receives light from the illumination source that passes through the microfluidic channel. The image sensor captures image frames containing raw hologram images of the moving objects passing through the microfluidic channel. The image frames are subject to image processing to reconstruct phase and/or intensity images of the moving objects for each color. The reconstructed phase and/or intensity images are then input to a trained deep neural network that outputs a phase recovered image of the moving objects. The trained deep neural network may also be trained to classify object types.

The present invention provides a surface shape measuring device and a surface shape measuring method which do not require a physical reference plane and can improve measurement accuracy without using a mechanical adjustment mechanism. The illumination light condensing point P.sub.Q and the reference light condensing point P.sub.L are arranged as mirror images of each other with respect to the virtual plane VP, and each data of the object light O, being a reflected light of the spherical wave illumination light Q, and the inline spherical wave reference light L is recorded on each hologram. On the virtual plane VP, the reconstructed object light hologram h.sup.V for measurement is generated, and the spherical wave optical hologram s.sup.V representing a spherical wave light emitted from the reference light condensing point P.sub.L is analytically generated. The height distribution of the surface to be measured of the object 4 is obtained from the phase distribution obtained by dividing the reconstructed object light hologram h.sup.V by the spherical wave light hologram s.sup.V. High-accuracy surface shape measurement without requiring a reference plane such as a glass substrate is realized by comparing the phase data of the reflected light acquired from the surface to be measured and the phase distribution on the plane cut surface of the spherical wave obtained analytically.

A method for multi-spectral scattering-matrix tomography includes a step of splitting an input light signal into an incident light signal and a reference light signal. The sample light signal is directed to a sample in either a reflection configuration or a transmission configuration such that an output light signal includes light scattered from or transmitted through the sample. The incident signal and the reference light signal are directed to a camera angled to allow for amplitude and phase to be calculated by off-axis holography. A total light signal is measured with a camera that is a coherent sum of the reference light signal and the output signal. The total light signal for each light frequency and each incident angle are collected as collected total light signal data. A computing device derives an image of the sample from a calculated reflection matrix or transmission matrix or both of them.