Provided is an ophthalmologic apparatus including: an acquisition unit configured to acquire tomographic information of an eye to be examined using information on interference light between return light from the eye to be examined, which is irradiated with measurement light, and reference light; and a vitreous structure detection unit configured to detect a vitreous structure of the eye to be examined using tomographic information of the eye to be examined that is acquired after at least one of the difference in optical path length between the measurement light and the reference light and the in-focus position is controlled, wherein the acquisition unit is configured to acquire tomographic information of the vitreous structure.

A white light interferometric metrology device operates in the image plane and objective pupil plane. The interferometric metrology device extracts the electric field with complex parameters and that is a function of azimuth angle, angle of incidence and wavelength from interferometric data obtained from the pupil plane. Characteristics of the sample are determined using the electric field based on an electric field model of the azimuth angle, the angle of incidence and the wavelength that is specific for a zero diffraction order. A center of the pupil in the pupil plane may be determined based on a Fourier transform of the interferometric data at each new measurement and used to convert each pixel from the camera imaging the objective pupil plane into a unique set of angle of incidence and azimuth angle of light incident on the sample.

An agile optical imaging system for optical coherence tomography imaging using a tunable source comprising a wavelength tunable VCL laser is disclosed. The tunable source has long coherence length and is capable of high sweep repetition rate, as well as changing the sweep trajectory, sweep speed, sweep repetition rate, sweep linearity, and emission wavelength range on the fly to support multiple modes of OCT imaging. The imaging system also offers new enhanced dynamic range imaging capability for accommodating bright reflections. Multiscale imaging capability allows measurement over orders of magnitude dimensional scales. The imaging system and methods for generating the waveforms to drive the tunable laser in flexible and agile modes of operation are also described.

An SS-OCT apparatus includes a clock generator configured as an interferometer including an optical path through which part of light emitted from a light source passes, the optical path being split into a first optical path and a second optical path having an optical path length difference relative to the first optical path, to generate a clock used by a converter sampling an analog signal; a tomographic image obtaining unit configured to obtain a tomographic image of a fundus by using a digital signal converted from the analog signal sampled by the converter using the generated clock; and a scan unit configured to scan illumination light across the fundus at a scan angle of 47 degrees or more in air. The tomographic image obtaining unit is configured to obtain a tomographic image of the fundus at a distance of 4.0 mm more within an eyeball in a depth range.

A three-dimensional shape measuring device includes a holder that changes the reference light path length in response to temperature change, and a temperature adjusting unit that adjusts a temperature of the holder to a target temperature, so as to make a measurement light path length equal to a reference light path length with high accuracy at low cost regardless of a temperature of an installation environment. A three-dimensional shape measuring device includes a temperature adjusting unit that adjusts the temperature of the holder and a temperature control unit that controls the temperature adjusting unit so as to selectively switch a measurement mode between a first measurement mode in which the reference light path length is made equal to a measurement light path length and a second measurement mode in which the reference light path length is made different from the measurement light path length.

In order to measure the contrast of interference in an interference-based, closed-loop, phase-modulating optical sensor device, the gain of the feedback loop in a feedback controller (12) is evaluated. This gain is found to be a measure for the contrast. The contrast evaluated in this way can e.g. be used for period-disambiguation when determining the measurand of the sensor device. The sensor device can e.g. be a high-voltage sensor or a current sensor.

An interferometer system to generate an interference signal of a surface of a sample includes a broadband illuminator to provide a broadband illumination beam, a beam splitter to split the broadband illumination beam in a reference beam for reflection on a reference reflector and a measurement beam for reflection on the surface of the sample, and a detector to receive an interference radiation intensity created between the reference beam reflected from the reference reflector and the reflected measurement beam from the surface of the sample to generate an interference signal. The interferometer system having a continuous variable broadband reflector in the beam splitter and/or the reference reflector to adjust the broadband radiation intensity balance between the measurement beam and the reference beam.

A cat's-eye swept source laser designed for Optical Coherence Tomography (OCT) and spectroscopy, focusing on reducing relative intensity noise (RIN). It features a semiconductor gain chip and a cat's-eye configuration with an adjustable bandpass filter managed by an angle-control actuator, optimizing wavelength tuning and noise reduction. This efficient design can eliminate the need for a thermoelectric cooler, simplifying the system and reducing costs. The laser supports various imaging techniques, offering improved signal-to-noise ratios and high-resolution images.

A method for absolute phase measurement for complex coherence coefficient of an object comprises: firstly, processing fringe data measured by interferometry on any aperture pairs of an equivalent pupil plane of an optical imaging system to obtain an interference term and envelope and extreme values thereof; secondly, selecting extreme value A of light intensity from an interval of relatively stable extreme values change on one side of a curve envelope with zero optical path difference, and selecting two extreme values B and C of light intensity closest to extreme value A on other side of the curve envelope with zero optical path difference, where B>AC or C>AB; thirdly, counting number of fringe periods between A and C or A and B; and fourthly, according to the number of fringe periods, selecting a formula to calculate absolute phase of complex coherence coefficient of the object.

An agile optical imaging system for optical coherence tomography imaging using a tunable source comprising a wavelength tunable VCL laser is disclosed. The tunable source has long coherence length and is capable of high sweep repetition rate, as well as changing the sweep trajectory, sweep speed, sweep repetition rate, sweep linearity, and emission wavelength range on the fly to support multiple modes of OCT imaging. The imaging system also offers new enhanced dynamic range imaging capability for accommodating bright reflections. Multiscale imaging capability allows measurement over orders of magnitude dimensional scales. The imaging system and methods for generating the waveforms to drive the tunable laser in flexible and agile modes of operation are also described.