A method for reconstructing a digital hologram of a surface having at least one three- dimensional feature thereon, including acquiring a digital hologram of the surface, reconstructing a wavefront based on the digital hologram, generating a phase map of at least a portion of the surface based on the wavefront, the phase map including phase ambiguities, obtaining at least one additional image of the surface, obtaining height data relating to the three-dimensional feature from the at least one additional image of the surface, the height data being obtained with a first precision, resolving the phase ambiguities based on the height data and deriving a height of the at least one three- dimensional feature based on the phase map following the resolving of the phase ambiguities therein, the height being derived with a second precision more precise than the first precision.

Various optical systems equipped with diode laser light sources are discussed in the present application. One example system includes a diode laser light source for providing a beam of radiation. The diode laser has a spectral output bandwidth when driven under equilibrium conditions. The system further includes a driver circuit to apply a pulse of drive current to the diode laser. The pulse causes a variation in the output wavelength of the diode laser during the pulse such that the spectral output bandwidth is at least two times larger the spectral output bandwidth under the equilibrium conditions.

A holographic interferometer, comprising: an imaging device capturing an interference pattern created by at least two polarized light beams; a structured phase retardation element located in an optical path of at least one polarized light beam of the at least two polarized light beams; and a polarizer located between the imaging device and the structured phase retardation element, the polarizer projects each polarization of each of the at least two polarized light beams on a single axis to create the interference pattern on the imaging device.

Some embodiments are directed to a technique having an off-axis interferometric geometry that is capable of spatially multiplexing at least six complex wavefronts, while using the same number of camera pixels typically needed for a single off-axis hologram encoding a single complex wavefront. Each of the at least six parallel complex wavefronts is encoded into an off-axis hologram with a different fringe orientation, and all complex wavefronts can be fully reconstructed. This technique is especially useful for highly dynamic samples, as it allows the acquisition of at least six complex wavefronts simultaneously, optimizing the amount of information that can be acquired in a single camera exposure. The off-axis multiplexing holographic system of some embodiments provide an off-axis holography modality that is more camera spatial bandwidth efficient than on-axis holography. Moreover, the off-axis interferometric system allows simple simultaneous acquisition of at least six holographic channels, making it attractive for imaging dynamics.

A holographic interferometer, comprising: an imaging device capturing an interference pattern created by at least two polarized light beams; a structured phase retardation element located in an optical path of at least one polarized light beam of the at least two polarized light beams; and a polarizer located between the imaging device and the structured phase retardation element, the polarizer projects each polarization of each of the at least two polarized light beams on a single axis to create the interference pattern on the imaging device.

The invention relates to a device, such as a digital holographic microscope, for detecting and processing a first full image of a measurement object, measured with a first offset, wherein an arrangement is provided for generating at least one further full image with at least one offset that differs from the first offset.

A non-destructive iterative interferometric tomographic technique for imaging and reconstruction of phase objects as well as objects with complex permittivity and, particularly, to iterative optical diffraction tomographic (iODT) imaging and reconstruction of phase objects with high refractive index (RI) contrast, complex structures, and/or large optical path differences (OPDs) against the background, which cause multiple scattering, and applications thereof.

A device for manufacturing a piece with addition of material includes an optical inspection unit for capturing at least one holographic image of a transformation zone of the material, in real time while the piece is being manufactured. A processor then characterizes a topography of the transformation zone from each holographic image. Such manufacturing device may be in particular of 3D-printer type, or a welding device.

A measurement device, for measuring the shape of an interface to be measured of an optical element having a plurality of interfaces, the device including a measurement apparatus with at least one interferometric sensor illuminated by a low-coherence source, for directing a measurement beam towards the optical element to pass through the plurality of interfaces, and to detect an interference signal resulting from interferences between the measured measurement beam reflected by the interface and a reference beam, a positioning apparatus configured for relative positioning of a coherence area of the interferometric sensor at the level of the interface to be measured, and a digital processor for producing, based on the interference signal, an item of shape information of the interface to be measured according to a field of view.

A control device includes a processor. The processor acquires positional information indicating a position of an observation target. The processor sets, from among a plurality of irradiation positions, a required irradiation position, which is an irradiation position corresponding to the position of the observation target indicated by the positional information and is an irradiation position required for obtaining a plurality of the interference fringe images that are sources of a super-resolution interference fringe image having a resolution exceeding a resolution of an imaging element. The processor causes a light source to emit an illumination light from the required irradiation position by controlling an operation of the light source, and causes the imaging element to outputs the interference fringe image at each required irradiation position.