Abstract: Methods and apparatus for generating ultrashort optical pulses. Polarized pulses of a near-infrared source are launched substantially along a principle axis of a birefringent photonic crystal fiber characterized by normal dispersion at all wavelengths of transmission of the photonic crystal fiber. Supercontinuum pulses are generated from the photonic crystal fiber and compressed to form compressed pulses. Highly polarized supercontinuum pulses provide for transform-limited compressed pulse durations.

Abstract: A method of forming an image of tissue. The method includes non-invasively inserting a fiber-based device into a patient's ear canal and acquiring OCT data from ear tissue while the fiber-based device is in the ear canal. The method also includes converting the OCT data into at least one image.

Abstract: A system that incorporates teachings of the present disclosure may include, for example, a method involving capturing spectral interference from an optical coherence tomography imaging probe comprising a micro-electro-mechanical system (MEMS) scanning mirror, and a partial reflector for supplying images to an image sensor. Additional embodiments are disclosed.

Abstract: An apparatus and methods for generating a substantially supercontinuum-free widely-tunable multimilliwatt source of radiation characterized by a narrowband line profile. The apparatus and methods employ nonlinear optical mechanisms in a nonlinear photonic crystal fiber (PCF) by detuning the wavelength of a pump laser to a significant extent relative to the zero-dispersion wavelength (ZDW) of the PCF. Optical phenomena employed for the selective up-conversion in the PCF include, but are not limited to, four-wave mixing and Cherenkov radiation. Tunability is achieved by varying pump wavelength and power and by substituting different types of PCFs characterized by specified dispersion properties.

Abstract: A method of analyzing tissue includes inserting a radiation source into tissue, impinging radiation upon the tissue, obtaining a sample signal of the radiation that impinges upon the tissue, and determining a refractive index of the tissue from the sample signal. The method may also include determining at least one other optical property of the tissue. The method may provide for identifying tissue as part of a biopsy method. A device for analyzing tissue may include a low-coherence interferometer and a probe optically coupled to the interferometer, where the probe includes a radiation source.

Abstract: Methods and apparatus for selectively driving the vibrations of normal modes of a target molecule into coherence using stimulated Raman scattering. In concert, many vibrations produce a larger anti-Stokes signal than a single vibration. The same illumination does not drive other molecules to have coherent vibrations, so these molecules produce a weaker signal. Target and confounder molecules can be distinguished by pulses that drive many vibrations coherently, with applications in coherent Raman microspectroscopy.

Abstract: A spectral-domain magnetomotive optical coherence tomography apparatus, includes (a) a spectral-domain optical coherence tomography device, and (b) a magnet. The magnet is coupled with the optical coherence tomography device so that changes in the magnetic field are coordinated with collection of data by the optical coherence tomography device. This device may be used to examine a sample by spectral-domain magnetomotive optical coherence tomography, which includes examining the sample with a spectral-domain optical coherence tomography device, to collect optical coherence tomography data. The sample contains magnetic particles, and the magnetic particles are subjected to a changing magnetic field during the examining.

Abstract: A method of forming an image of a sample includes performing SOCT on a sample. The sample may include a contrast agent, which may include an absorbing agent and/or a scattering agent. A method of forming an image of tissue may include selecting a contrast agent, delivering the contrast agent to the tissue, acquiring SOCT data from the tissue, and converting the SOCT data into an image. The contributions to the SOCT data of an absorbing agent and a scattering agent in a sample may be quantified separately.

Abstract: Methods and apparatus for three-dimensional imaging of a sample. A source is provided of a beam of light characterized by partial spatial coherence. The beam is focused onto a sample and scattered light from the sample is superposed with a reference beam derived from the source onto a focal plane detector array to provide an interference signal. A forward scattering model is derived relating measurement data to structure of an object to allow solutions of an inverse scattering problem, based upon the interference signal so that a three-dimensional structure of the same may be inferred. The partial spatial coherence of the source, which may be fixed or variable, may advantageously provide for rejection of multiple scattering artifacts and thus improve image quality.

Abstract: A system that incorporates teachings of the present disclosure may include, for example, a sensor having a pulse oximeter sensor to measure an oxygen saturation level in a liquid, a magnetic source coupled to the pulse oximeter sensor, and a controller to control the pulse oximeter sensor and the magnetic source, and to measure a mechanical effect on the liquid responsive to the magnetic source applying a magnetic field to the liquid. Additional embodiments are disclosed.

Abstract: A method of examining a sample, which includes: exposing a reference to a first set of electromagnetic radiation, to form a second set of electromagnetic radiation scattered from the reference; exposing a sample to a third set of electromagnetic radiation to form a fourth set of electromagnetic radiation scattered from the sample; and interfering the second set of electromagnetic radiation and the fourth set of electromagnetic radiation. The first set and the third set of electromagnetic radiation are generated from a source; at least a portion of the second set of electromagnetic radiation is of a frequency different from that of the first set of electromagnetic radiation; and at least a portion of the fourth set of electromagnetic radiation is of a frequency different from that of the third set of electromagnetic radiation.

Abstract: A method of forming an image of a sample, comprising: forming an image of a mixture, by exposing the mixture to electromagnetic radiation; wherein the mixture comprises the sample and plasmon-resonant nanoparticles, and wherein the electromagnetic radiation is in the frequency range of infra-red to ultraviolet light.

Abstract: Methods and apparatus for three-dimensional imaging of a sample. A source is provided of a beam of substantially collimated light characterized by a temporally dependent spectrum. The beam is focused in a plane characterized by a fixed displacement along the propagation axis of the beam, and scattered light from the sample is superposed with a reference beam derived from the substantially collimated source onto a focal plane detector array to provide an interference signal. A forward scattering model is derived relating measured data to structure of an object to allow solution of an inverse scattering problem based upon the interference signal so that a three-dimensional structure of the sample may be inferred in near real time.

Abstract: A method of examining a sample comprises exposing the sample to a pump pulse of electromagnetic radiation for a first period of time, exposing the sample to a stimulant pulse of electromagnetic radiation for a second period of time which overlaps in time with at least a portion of the first exposing, to produce a signal pulse of electromagnetic radiation for a third period of time, and interfering the signal pulse with a reference pulse of electromagnetic radiation, to determine which portions of the signal pulse were produced during the exposing of the sample to the stimulant pulse. The first and third periods of time are each greater than the second period of time.

Abstract: A method of forming an image of tissue. The method includes beginning an invasive procedure on a patient exposing tissue. The method then includes acquiring OCT data from the exposed tissue and converting the OCT data into at least one image. The method also includes ending the invasive procedure after the converting of the data.

Abstract: A spectral-domain magnetomotive optical coherence tomography apparatus, includes (a) a spectral-domain optical coherence tomography device, and (b) a magnet. The magnet is coupled with the optical coherence tomography device so that changes in the magnetic field are coordinated with collection of data by the optical coherence tomography device. This device may be used to examine a sample by spectral-domain magnetomotive optical coherence tomography, which includes examining the sample with a spectral-domain optical coherence tomography device, to collect optical coherence tomography data. The sample contains magnetic particles, and the magnetic particles are subjected to a changing magnetic field during the examining.

Abstract: A method of forming an image of tissue. The method includes non-invasively inserting a fiber-based device into a patient's ear canal and acquiring OCT data from ear tissue while the fiber-based device is in the ear canal. The method also includes converting the OCT data into at least one image.

Abstract: Methods and apparatus for three-dimensional imaging of a sample. A source is provided of a beam of light characterized by partial spatial coherence. The beam is focused onto a sample and scattered light from the sample is superposed with a reference beam derived from the source onto a focal plane detector array to provide an interference signal. A forward scattering model is derived relating measurement data to structure of an object to allow solutions of an inverse scattering problem, based upon the interference signal so that a three-dimensional structure of the same may be inferred. The partial spatial coherence of the source, which may be fixed or variable, may advantageously provide for rejection of multiple scattering artifacts and thus improve image quality.

Abstract: Methods for employing coherent bundles of optical fibers, whether single- or multi-mode, for optical coherence tomography or optical coherence microscopy. Either a substantially monochromatic source or a broadband source is spatially decohered and/or spatially filtered prior to coupling into the fiber bundle for illumination of a sample. A scatter signal from features disposed beneath the surface of the sample is interfered with a reference signal derived, at either end of the fiber bundle, from the identical source of illumination.

Abstract: Methods and apparatus for three-dimensional imaging of a sample. A source is provided of a beam of substantially collimated light characterized by a temporally dependent spectrum. The beam is focused in a plane characterized by a fixed displacement along the propagation axis of the beam, and scattered light from the sample is superposed with a reference beam derived from the substantially collimated source onto a focal plane detector array to provide an interference signal.