An interference imaging device includes a light interference generator that includes: a light wave splitter configured to reflect a part of incident light and to allow a remaining part of the incident light to pass through; a phase modulator configured to modulate a phase of incident light that has passed through the light wave splitter; and a reflector configured to reflect the phase-modulated incident light from the phase modulator so that the reflected, phase-modulated incident light overlaps with incident light that has been reflected by the light wave splitter.

A simultaneous phase-shift point diffraction interferometer and method for detecting wave aberration. The interferometer comprises an ideal spherical wave generation module, an optical system to be measured, an image plane mask, a polarization phase shift module, a two-dimensional polarization imaging photodetector and a data processing unit. Single photodetector is adopted to realize simultaneous detection of more than three phase shift interference patterns, and has the advantages that environmental interference suppression, a flexible optical path, high measurement accuracy, and calibration of system errors of the interferometer may be realized.

A method for analyzing the wavefront effect of an optical system includes: illuminating a measurement mask (110, 310) with illumination light, producing an interferogram in a specified plane using a diffraction grating (150) from a wavefront from the illuminated measurement mask and traveling through the optical system; and capturing the interferogram with a detector (170). Different angular distributions of the illumination light incident on the measurement mask are produced via a mirror arrangement of independently settable mirror elements. A plurality of interferograms are captured in a plurality of measurement steps, wherein these measurement steps differ respectively in angular distribution of the illumination light that is incident on the measurement mask. A matching wavefront deviation portion in the measurement results obtained respectively in the measurement steps is ascertained to determine the respective system wavefront deviations of the optical system for the pupil regions illuminated respectively in the individual measurement steps.

An interference imaging device includes a light interference generator that includes: a light wave splitter configured to reflect a part of incident light and to allow a remaining part of the incident light to pass through; a phase modulator configured to modulate a phase of incident light that has passed through the light wave splitter; and a reflector configured to reflect the phase-modulated incident light from the phase modulator so that the reflected, phase-modulated incident light overlaps with incident light that has been reflected by the light wave splitter.

A method for analyzing the wavefront effect of an optical system includes: illuminating a measurement mask (110, 310) with illumination light, producing an interferogram in a specified plane using a diffraction grating (150) from a wavefront from the illuminated measurement mask and traveling through the optical system; and capturing the interferogram with a detector (170). Different angular distributions of the illumination light incident on the measurement mask are produced via a mirror arrangement of independently settable mirror elements. A plurality of interferograms are captured in a plurality of measurement steps, wherein these measurement steps differ respectively in angular distribution of the illumination light that is incident on the measurement mask. A matching wavefront deviation portion in the measurement results obtained respectively in the measurement steps is ascertained to determine the respective system wavefront deviations of the optical system for the pupil regions illuminated respectively in the individual measurement steps.

According to a first aspect, there is provided a method of holographic wavefront sensing, the method including: receiving a light beam, which has a wavefront to be analyzed, on a transparent, flat substrate, which is provided with a lattice of opaque dots, wherein the substrate is arranged above an image sensor; detecting by the image sensor an interference pattern formed by diffracted light, being scattered by the opaque dots, and undiffracted light of the light beam received by the image sensor; processing the detected interference pattern to digitally reconstruct a representation of a displaced lattice of opaque dots, which would form the interference pattern on the image sensor upon receiving the light with a known wavefront; and comparing the representation of the displaced lattice to a known representation of the lattice of opaque dots on the substrate to determine a representation of the wavefront form of the received light beam.

A collimation evaluation device includes a first reflection member, a second reflection member, a screen, and a housing. A first reflection surface of the first reflection member and a first reflection surface of the second reflection member face each other and are parallel to each other. Further, interference fringes are formed on the screen by light L.sub.12 reflected on the first reflection surface of the first reflection member and a second reflection surface of the second reflection member and light L.sub.21 reflected on a second reflection surface of the first reflection member and the first reflection surface of the second reflection member, and collimation of incident light is evaluated on the basis of a direction of the interference fringes.

Systems, methods and other embodiments associated with spatial-domain Low-coherence Quantitative Phase Microscopy (SL-QPM) are described herein. SL-QPM can detect structural alterations within cell nuclei with nanoscale sensitivity (0.9 nm) (or nuclear nano-morphology) for nano-pathological diagnosis of cancer. SL-QPM uses original, unmodified cytology and histology specimens prepared with standard clinical protocols and stains. SL-QPM can easily integrate in existing clinical pathology laboratories. Results quantified the spatial distribution of optical path length or refractive index in individual nuclei with nanoscale sensitivity, which could be applied to studying nuclear nano-morphology as cancer progresses. The nuclear nano-morphology derived from SL-QPM offers significant diagnostic value in clinical care and subcellular mechanistic insights for basic and translational research. Techniques that provide for depth selective investigation of nuclear and other cellular features are disclosed.

According to a first aspect, there is provided a method of holographic wavefront sensing, the method including: receiving a light beam, which has a wavefront to be analyzed, on a transparent, flat substrate, which is provided with a lattice of opaque dots, wherein the substrate is arranged above an image sensor; detecting by the image sensor an interference pattern formed by diffracted light, being scattered by the opaque dots, and undiffracted light of the light beam received by the image sensor; processing the detected interference pattern to digitally reconstruct a representation of a displaced lattice of opaque dots, which would form the interference pattern on the image sensor upon receiving the light with a known wavefront; and comparing the representation of the displaced lattice to a known representation of the lattice of opaque dots on the substrate to determine a representation of the wavefront form of the received light beam.

A point diffraction interferometric wavefront aberration measuring device comprising an optical source, an optical splitter, a first light intensity and polarization regulator, a phase shifter, a second light intensity and polarization regulator, an ideal wavefront generator, an object precision adjusting stage, a measured optical system, an image wavefront detection unit, an image precision adjusting stage, and a data processing unit. The center distance between the first output port and the second output port of the ideal wavefront generator is smaller than the diameter of the isoplanatic region of the measured optical system and is greater than the ratio of the diameter of the image point dispersion speckle of the measured optical system over the amplification factor thereof. A method for detecting wavefront aberration of the optical system is also provided by using the device.