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.

In one embodiment, a sensorless adaptive optics imaging system includes a source of light, an optical delivery unit having a wavefront modifying element, and an optical coherence tomography (OCT) sensor configured to acquire OCT images based on light emitted by the source of light and transmitted through the optical delivery unit. The system also includes a processing unit that can: process the OCT images, and determine an adjustment of parameters of the wavefront modifying element. In some embodiments, the system includes a multi-photon microscopy (MPM) sensor that acquires MPM images based on the light transmitted through the optical delivery unit.

A system and method for phase-readout/control and active stabilization on arbitrary interferometric phase in the optical interferometer platform is disclosed. The method makes use of a bi-colored polarization-multiplexed reference laser scheme. The disclosed scheme is based on two phase-locked reference signals with different frequencies that together remove the phase ambiguity. The two signals are polarization-multiplexed (either in free-space or optical fiber implementations) to enable easy separation and combining of these two signals through the use of polarization beam-splitters. The disclosed scheme provides a one-to-one map between phase and feedback signal levels, and enables phase-readout and stabilization even when one of the feedback-signals is at a maximum/minimum.

A light measurement device that maintains high measurement precision. The light measurement device includes: light source that irradiates light upon measurement object; branch part that splits transmitted light or reflected light from measurement object; phase-changing unit that changes the phase of one beam of the branched light beams; phase-fixing unit that maintains the phase of the other beam of the branched light beams; adjustment mechanism, which is provided in phase-changing unit or phase-fixing unit, for adjusting the propagation direction of light; multiplexer that causes the light emitted by each of phase-changing unit and phase-fixing unit to interfere with each other; detection unit that detects light that is interfered with by multiplexer; and control unit that controls the adjustment mechanism on the basis of the luminance values of an interference image that is detected by detection unit and adjusts the propagation direction of light in phase-changing unit or phase-fixing unit.

A workpiece processing machine that includes: a beam emission head for providing a beam for processing the workpiece, an optical interferometer for splitting, redirecting, and detecting the beam, an adjustment element for changing a second portion of a power of the beam redirected from a retroreflector to a detector, and a control unit for actuating the adjustment element to control a ratio between a first power portion of the beam redirected from the workpiece to the detector and the second power portion of the beam redirected from the retroreflector to the detector to a target ratio.

A method of calibrating an apparatus configured to perform optical coherence tomography to measure depth of an article of a prescribed type comprises (a) using an existing measurement system configured to measure depth, measuring a sample of the article to obtain reference depth measurements; b) using the optical coherence tomography apparatus, capturing sectional images of the sample at the same positions at which the reference depth measurements were obtained; c) determining, in each sectional image, a number of pixels in a depth direction of the sample; and d) determining, using the reference depth measurements and the numbers of pixels from the sectional images, a correlation curve to associate pixels in images captured by optical coherence tomography with physical depth. Measuring the sample comprises performing plural measurements at different positions on the sample. Each measurement is in the form of a profile of the sample at a corresponding position thereon.

An interferometer including a master laser, a slave laser and optical elements is provided. The optical elements direct and combine a master laser beam and a slave laser beam into a sensing phase measurement loop to provide a sensing beat signal and a reference phase lock loop to provide a reference beat signal. An electronic circuit portion is coupled to receive the sensing and reference beat signals. The electronic circuit portion includes a clock, at least one numerically controlled oscillator, at least one mixer and an interferometer output. The at least one numerically controlled oscillator has a clock input coupled to the clock. The at least one mixer has a first input to receive the sensing beat signal and a second input to receive an output of the at least one numerically controlled oscillator. The interferometer output is coupled to receive an output of the at least one mixer.

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.

An optical fiber interrogator for interrogating optical fiber that includes fiber Bragg gratings (FBGs). The interrogator includes a light source operable to emit phase coherent light, amplitude modulation circuitry optically coupled to the light source and operable to generate pulses from the light, and control circuitry communicatively coupled to the amplitude modulation circuitry that is configured to perform a method for interrogating the optical fiber. The method includes generating a pair of light pulses by using the amplitude modulation circuitry to modulate light output by the light source without splitting the light.

An optical fiber interrogator for interrogating optical fiber that includes fiber Bragg gratings (FBGs). The interrogator includes a light source operable to emit phase coherent light, amplitude modulation circuitry optically coupled to the light source and operable to generate pulses from the light, and control circuitry communicatively coupled to the amplitude modulation circuitry that is configured to perform a method for interrogating the optical fiber. The method includes generating a pair of light pulses by using the amplitude modulation circuitry to modulate light output by the light source without splitting the light.