The present disclosure relates to an apparatus for measuring a thickness and a surface profile of a multilayered film structure using an imaging spectral optical system and a measuring method. More specifically, the present disclosure relates to a method and an apparatus which measure a thickness and a surface profile of a multilayered thin film structure by applying a method for obtaining an absolute reflectance value for an object to be measured having a multilayered thin film using a reflected light measuring method and extracting a phase from an interference signal with a reference mirror using a phase shift algorithm.

A system and method for generating, enhancing, and detecting the amplitude and phase modulation of a laser under a condition of self-mixing is provided. The system may comprise a laser and a detector to extract the characteristic self-mix signal, which is then interpreted using algorithms implemented in hardware or software. In the case of the laser being a Vertical Cavity Surface Emitting laser (VCSEL), the output signal can be detected by monitoring the surface light emission by means of a beam splitter, or in some embodiments as emission from the bottom surface of the laser. In some embodiments, the system may further comprise a wavelength filter such as an etalon in the signal path.

A waveguide interferometer includes a multicore fiber used a multicore waveguide, where the multicore waveguide includes a coupler section formed by tapering a portion of the multicore waveguide so that one core though which a light source is fed is optically coupled to another core that is terminated differently that the core into which the source signal is provided. The terminations respond differently upon being exposed to an environmental condition or substance, and the difference in response to the environmental condition or substance results in a shift in interference of the light reflected back through the multicore waveguide, which is detected with a detector on the same side of the multicore waveguide as the light source.

A system and method for performing Optical Coherence Tomography on a sample utilizes collimated, phase modulated beams of light in an interferometer. At least one of the beams of light utilized exists as an Airy beam for at least a portion of the procedure, obviating any deleterious impact caused by the Gaussian beam diffraction. The system may incorporate a light source, polarization beam splitter, delay line, non-polarization beam splitters, lenses, phase masks, waveplates, and mirrors, any or all of which may be controlled by a computing element.

The optical module for optical height measurement includes a laser light source, an irradiation optical system, a detection optical system, and a detector. The laser light source is configured to irradiate the layer-structured specimen with a light beam. The irradiation optical system includes an objective lens. The objective lens is located to be approximately perpendicular to the layer-structured specimen. The detection optical system is configured to guide a reflected light reflected by the layer-structured specimen and a light passing through the objective lens and an aperture-restrictor-for-return to the detector. The aperture-restrictor-for-return is located immediately after the objective lens. The aperture-restrictor-for-return is configured to restrict the reflected light and cause only a light in a high NA region to pass through. The detector is configured to convert an entered light into a light detection signal. The detector includes a multi-divided detector array.

A bending detecting system includes a light guide, a first grating and a light detector. The light guide has elongated shape and is configured to guide an incident light in a propagating direction. The light guide includes a core and a cladding disposed around the core. The first grating is disposed in a boundary area, the boundary area including an outer surface of the core, and an adjacent area that is adjacent to the outer surface. The first grating includes a first periodic structure along the propagating direction with a first pitch, and is configured to generate a first diffracted light from the incident light. The light detector is configured to detect the first diffracted light from the first grating, and detect a bending of the light guide based upon an optical feature amount of the first diffracted light.

An interference observation apparatus includes a light source which outputs incoherent light, a beam splitter, a sample holding table, an objective lens, a reference mirror, a lens, an aberration correction plate, a piezo element, a tube lens, a beam splitter, an imaging unit, a photodetector, an image acquisition unit, and a control unit. The control unit obtains an interference intensity of combined light on the basis of a detection signal output from the photodetector, and adjusts an interference optical system to increase the interference intensity.

Provided is a pupil image measuring device including a light source configured to generate and output a light, a stage on which a measurement target is loaded, an optical system configured to transmit the light output from the light source, to the measurement target, a detector configured to detect a light reflected from the measurement target, and a spatial light distribution controller configured to adjust an intensity or amount of the light output from the light source or the reflected light, for each space of a plurality of spaces of the spatial light distribution controller, wherein the spatial light distribution controller is disposed on a pupil plane.

Retinal imaging systems and related methods employ a user specific approach for controlling the reference arm length in an optical coherence tomography (OCT) imaging device. A method includes generating a signal indicative of a position of a feature of a user's head relative to an OCT imaging device. A user specific reference arm adjustment length range for the user within a reference arm adjustment length range of the OCT device is determined based on the signal. A reference arm length adjustment module is controlled during an imaging of the retina to vary a reference arm length of the OCT imaging device within the user specific reference arm adjustment length range to identify an imaging reference arm length for which an OCT image detector of the OCT imaging device produces an OCT signal corresponding to the retina of the user.

The invention relates to a full-field OCT method for generating an imaging of an ocular fundus (31), in which short-coherent light (22) is emitted and split into an object beam path (25) and a reference beam path (24). The object beam path (25) is directed onto the ocular fundus (33). The reference beam path (24) and a portion of the object beam path (25) reflected by the ocular fundus (31) are directed onto an image sensor (32), such that an interference between the reference beam path (24) and the object beam path (25) occurs on the image sensor (32), wherein the reference beam path (24) impinges on the image sensor (32) at an angle deviating from the object beam path (25). Before impinging on the image sensor (32), the reference beam path (24) impinges on an optical correction element (27) in order to reduce a chromatic aberration within the reference beam path (24). Intensity information and phase information is determined from a capturing of the image sensor. A focus-adjusted image of the ocular fundus is calculated. The invention also relates to a system that is suitable for carrying out said method. Images of the ocular fundus can be captured without the beam path being previously adapted to the refractive power of the eye lens.