An interferometry apparatus comprising: a laser source operable to emit a first light beam; a beam splitter arranged to split the first light beam into an object beam and a reference beam, the object beam passing along an object beam arm and the reference beam passing along a reference beam arm; an adaptive delay line located a distance along the reference beam arm, the adaptive delay line being configured to provide, in use, one or more length-adjusted reference beams; a beam splitter arranged to recombine the object beam from the object beam arm and the length-adjusted reference beam(s) from the reference beam arm; and a photodetector operable to detect interference between the object beam and the length-adjusted reference beam(s).

Provided is a system for range detection including at least one beam source arrangement configured to provide illumination of certain coherence length, an optical arrangement, and a detection arrangement including at least one detector unit.

One or more devices, systems, methods and storage mediums for optical imaging medical devices, such as, but not limited to, Optical Coherence Tomography (OCT), single mode OCT, and/or multi-modal OCT apparatuses and systems, and methods and storage mediums for use with same, for performing automated polarization control, polarization diversity and/or balanced detection are provided herein. One or more embodiments may achieve polarization diversity and balanced detection (or photo-detection) under any imaging circumstances. One or more embodiments, may achieve polarization control functionality regardless of whether such control is automatic or manual. Additionally, one or more embodiments may achieve automated polarization control, may achieve balanced detection (or photo-detection), and/or may address potential disturbances, such as, but not limited to, polarization drift over time, temperature and/or mechanical perturbations or variations. One or more embodiments may include an optical receiver where polarization diversity and balanced detection may be optimized via motorized controls.

Methods, devices and systems are described that use a combination multiple light sources having different coherence lengths to measure surface characteristics of an object. One example system includes a two laser sources configured to operate at a first and a second center wavelength, a broadband source configured to operate at a range of wavelengths outside of the operating range of the at least two lasers, a phase mask array and a color filter arranged, respectively, to impart different phase delays and provide spectral filtering corresponding to the emitted radiation from the sources. A pixelated sensor device is positioned to simultaneously measure intensity values associated with a plurality of interferograms formed due to interference of light from the light sources after propagation through the phase mask array and the color filter. The measured intensity values enable the determination of surface characteristics of the object.

Methods, devices and systems are described that use a combination multiple light sources having different coherence lengths to measure surface characteristics of an object. One example system includes a two laser sources configured to operate at a first and a second center wavelength, a broadband source configured to operate at a range of wavelengths outside of the operating range of the at least two lasers, a phase mask array and a color filter arranged, respectively, to impart different phase delays and provide spectral filtering corresponding to the emitted radiation from the sources. A pixelated sensor device is positioned to simultaneously measure intensity values associated with a plurality of interferograms formed due to interference of light from the light sources after propagation through the phase mask array and the color filter. The measured intensity values enable the determination of surface characteristics of the object.

One or more devices, systems, methods and storage mediums for optical imaging medical devices, such as, but not limited to, Optical Coherence Tomography (OCT), single mode OCT, and/or multi-modal OCT apparatuses and systems, and methods and storage mediums for use with same, for performing automated polarization control, polarization diversity and/or balanced detection are provided herein. One or more embodiments may achieve polarization diversity and balanced detection (or photo-detection) under any imaging circumstances. One or more embodiments, may achieve polarization control functionality regardless of whether such control is automatic or manual. Additionally, one or more embodiments may achieve automated polarization control, may achieve balanced detection (or photo-detection), and/or may address potential disturbances, such as, but not limited to, polarization drift over time, temperature and/or mechanical perturbations or variations. One or more embodiments may include an optical receiver where polarization diversity and balanced detection may be optimized via motorized controls.

The range of measurement in spectrally controlled interferometry (SCI) is extended by superimposing multiple modulations on the low-coherence light used for the measurement. Optimally, a spectrally controllable light source modulated sinusoidally with low spectral frequency is combined with a delay line, such as provided by a Michelson interferometer. The resulting light is injected into a Fizeau interferometer to generate localized fringes at a distance corresponding to the effect of the spectrally modulated source combined with the optical path difference produced by the delay line. The combination provides a convenient way to practice SCI with all its advantages and with a range that can be extended to the degree required for any practically foreseeable application.

An efficient OCT data collection and processing method for obtaining a high-axial-resolution image with explicit ranging over an extended depth is described. The method includes collecting a first dataset at a transverse location of the sample. The first dataset comprises spectra of a bandwidth (k.sub.1) sampled at a spectral sampling interval (dk.sub.1). A second dataset comprising spectra of a bandwidth (k.sub.2) sampled at a spectral sampling interval (dk.sub.2) is collected. The bandwidth k.sub.2 is less than k.sub.1 and spectral sampling interval dk.sub.2 is less than dk.sub.1. The first and the second datasets are processed to generate at least one A-scan with an axial resolution higher than the axial resolution corresponding to the bandwidth k.sub.2 and a depth range larger than the depth range provided by sampling interval dk.sub.1.

A calibration system for calibrating a tilt angle of the fast steering mirror includes a position sensing device configured to generate a beam of electromagnetic radiation, and a diffractive optical element, positioned between the position sensing device and the fast steering mirror, the diffractive optical element being configured to divide the input beam into a plurality of output beams directed to the fast steering mirror. The position sensing device is configured to determine a tilt angle of the fast steering mirror. A method to calibrate a tilt angle of the fast steering mirror is further disclosed.

An efficient OCT data collection and processing method for obtaining a high-axial-resolution image with explicit ranging over an extended depth is described. The method includes collecting a first dataset at a transverse location of the sample. The first dataset comprises spectra of a bandwidth (k.sub.1) sampled ata spectral sampling interval (dk.sub.1). A second dataset comrising spectra of a bandwidth (k.sub.2) sampled ata spectral sampling interval (dk.sub.2) is collected. The bandwidth k.sub.2 is less than k.sub.1 and spectral sampling interval dk.sub.2 is less than dk.sub.1. The first and the second datasets are processed to generate at least one A-scan with an axial resolution higher than the axial resolution corresponding to the bandwidth k.sub.2 and a depth range larger than the depth range provided by sampling interval dk.sub.1.