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.

Disclosed is a method and associated apparatus for measuring a characteristic of interest relating to a structure on a substrate. The method comprises calculating a value for the characteristic of interest directly from the effect of the characteristic of interest on at least the phase of illuminating radiation when scattered by the structure, subsequent to illuminating said structure with said illuminating radiation.

A holographic imaging device and method realizes both a transmission type and a reflection type, and also realizes a long working distance wide field of view or ultra-high resolution. Object light emitted from an object, sequentially illuminated with parallel illumination light whose incident direction is changed, is recorded on a plurality of object light holograms for each incident direction using off-axis spherical wave reference light. The reference light is recorded on a reference light hologram using in-line spherical wave reference light being in-line with the object light. An object light wave hologram and its spatial frequency spectrum at the object position are generated for each incident direction using each hologram. A synthetic spectrum which occupies a wider frequency space is generated by matching each spectrum in the overlapping area, and a synthetic object light wave hologram with increased numerical aperture is obtained thereby.

When the optical system is illuminated with an illumination light flux emitted from one extant input image point, an interference image generated by superimposing an extant output light flux output from the optical system and a reference light flux coherent with the extant output light flux is imaged to acquire interference image data, and thus to acquire measured phase distribution, and this acquisition operation is applied to each extant input image point. Thus, each measured phase distribution is expanded by expanding functions μn(u, v) having coordinates (u, v) on a phase defining plane as a variable to be represented as a sum with coefficients Σn{Ajn.Math.μn(u, v)}. When the optical system is illuminated with a virtual illumination light flux, a phase Ψ(u, v) of a virtual output light flux is determined by performing interpolation calculation based on coordinates of a virtual light emitting point.

An imaging system for imaging a fluid sample includes a light source configured to generate a beam of light, an angled element disposed along an optical path of the beam of light, and a sample cartridge holder configured to receive a sample cartridge and configured to hold the sample cartridge in a first position in which an imaging region of the sample cartridge is disposed along the optical path. The system further includes a sensor configured to capture the beam of light after it passes through the angled element and the imaging region of the sample cartridge. The imaging region of the sample cartridge is configured to receive the sample fluid. A sample cartridge having a cover plate and a fluidics layer is also disclosed. The fluidics layer includes an opening, a fluid channel, and an imaging region configured to receive a whole blood sample.

Disclosed is a method of determining a complex-valued field relating to a structure, comprising: obtaining image data relating to a series of images of the structure, for which at least one measurement parameter is varied over the series and obtaining a trained network operable to map a series of images to a corresponding complex-valued field. The method comprises inputting the image data into said trained network and non-iteratively determining the complex-valued field relating to the structure as the output of the trained network. A method of training the trained network is also disclosed.

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 super-resolution holographic microscope includes a light source configured to emit input light, a diffraction grating configured to split the input light into first diffracted light and second diffracted light, a mirror configured to reflect the first diffracted light, a wafer stage arranged on an optical path of the second diffracted light and on which a wafer is configured to be arranged, and a camera configured to receive the first diffracted light that is reflected by the mirror and the second diffracted light that is reflected by the wafer to generate a plurality of hologram images of the wafer.

In situ investigation of microbial life in extreme environments can be carried out with microscopes capable of imaging 3-dimensional volumes and tracking particle motion. A lensless digital holographic microscope is disclosed that provides roughly 1.5 micron resolution in a compact, robust package suitable for remote deployment. High resolution is achieved by generating high numerical-aperture input beams with radial gradient-index rod lenses. The ability to detect and track prokaryotes was explored using bacterial strains of two different sizes. In the larger strain, a variety of motions were seen, while the smaller strain was used to demonstrate a detection capability down to micron scales.

A digital holographic apparatus includes a first hologram generating unit that generates a first hologram by causing first object light in a first observation direction to interfere with first reference light, the first object light being generated by irradiating an observation object with light having a first wavelength, the first reference light being derived from the light having the first wavelength; a second hologram generating unit that generates a second hologram by causing second object light in a second observation direction that differs from the first observation direction to interfere with second reference light, the second object light being generated by irradiating the observation object with light having a second wavelength, the second reference light being derived from the light having the second wavelength; a first image capturing unit that captures the first hologram; and a second image capturing unit that captures the second hologram.