Abstract: A system and method for determining eye surface contour using multifocal keratometry is disclosed. The system includes a light source, a light detector, a processor, a non-transitory machine-readable medium communicatively coupled to the processor, and instructions stored on the non-transitory machine-readable medium. The instructions, when loaded and executed by the processor, cause the processor to project a light, using the light source, onto a plurality of surfaces of an eye; create, using the light detector, an image of a plurality of reflections, each of the plurality of reflections created by reflecting the light off of one of the plurality of surfaces of the eye; determine that the plurality of reflections are in focus in the image; and calculate, based on the determination, a curvature of the plurality of surfaces of the eye based on the image.

Abstract: A system and method for determining eye surface contour using multifocal keratometry is disclosed. The system includes a light source, a light detector, a processor, a non-transitory machine-readable medium communicatively coupled to the processor, and instructions stored on the non-transitory machine-readable medium. The instructions, when loaded and executed by the processor, cause the processor to project a light, using the light source, onto a plurality of surfaces of an eye; create, using the light detector, an image of a plurality of reflections, each of the plurality of reflections created by reflecting the light off of one of the plurality of surfaces of the eye; determine that the plurality of reflections are in focus in the image; and calculate, based on the determination, a curvature of the plurality of surfaces of the eye based on the image.

Abstract: A system and method for determining eye surface contour using multifocal keratometry is disclosed. The system includes a light source, a light detector, a processor, a non-transitory machine-readable medium communicatively coupled to the processor, and instructions stored on the non-transitory machine-readable medium. The instructions, when loaded and executed by the processor, cause the processor to project a light, using the light source, onto a plurality of surfaces of an eye; create, using the light detector, an image of a plurality of reflections, each of the plurality of reflections created by reflecting the light off of one of the plurality of surfaces of the eye; determine that the plurality of reflections are in focus in the image; and calculate, based on the determination, a curvature of the plurality of surfaces of the eye based on the image.

Abstract: A system and method for determining eye surface contour using multifocal keratometry is disclosed. The system includes a light source, a light detector, a processor, a non-transitory machine-readable medium communicatively coupled to the processor, and instructions stored on the non-transitory machine-readable medium. The instructions, when loaded and executed by the processor, cause the processor to project a light, using the light source, onto a plurality of surfaces of an eye; create, using the light detector, an image of a plurality of reflections, each of the plurality of reflections created by reflecting the light off of one of the plurality of surfaces of the eye; determine that the plurality of reflections are in focus in the image; and calculate, based on the determination, a curvature of the plurality of surfaces of the eye based on the image.

Abstract: An apparatus for optical coherence tomography (OCT) comprises a light source, a first arm, a second arm, and a processing unit. The first arm has a first dispersive optical assembly that induces a first amount of dispersion into light from the light source and traversing the first arm, where the first arm is one of a sample arm and a reference arm of an interferometer. The second arm has a second dispersive optical assembly that induces a second amount of dispersion into light from the light source and traversing the second arm, where the second arm is the other of the sample arm and reference arm. The second amount of dispersion is larger than the first amount of dispersion. The processing unit processes an interferometry signal to perform OCT, where the interferometry signal represents a superposition of the light from the first arm and the light from the second arm.

Abstract: A method and system for instantaneous time domain optical coherence tomography (iTD-OCT) provides instantaneous optical depth profiles in an axial direction to a sample having scattering properties or that is at least partially reflective. An iTD-OCT instrument includes a spectroscopic detector having an internal optical axis and an array of detector pixels. A reference beam having a fixed optical path length is superpositioned along the optical axis with a measurement beam that includes back-scattered photons from the sample. The detector pixels capture a time domain interference pattern arising within the spectroscopic detector due to optical path length differences between photons from the reference beam and photons from the measurement beam. The iTD-OCT instrument may be implemented as a robust solid-state device with no moving parts.

Abstract: In a process for optical coherence tomography a plurality of first OCT slice images, in each first slice image representing a different slice of an object, are recorded. Subsequently a reference figure that is representative of the three-dimensional contour of at least one structural feature of the object in a given three-dimensional coordinate system is ascertained by feature recognition of the at least one structural feature in the first slice images. Then a plurality of second OCT slice images, each second slice image representing a different slice of the object, are recorded. At least a fraction of the second slice images are displaced in the coordinate system until each second slice image is in feature overlap with the reference figure. Lastly, a set of three-dimensional OCT image data is generated at least from the feature-overlapped second slice images.

Abstract: An apparatus for optical coherence tomography (OCT) comprises a light source, a first arm, a second arm, and a processing unit. The first arm has a first dispersive optical assembly that induces a first amount of dispersion into light from the light source and traversing the first arm, where the first arm is one of a sample arm and a reference arm of an interferometer. The second arm has a second dispersive optical assembly that induces a second amount of dispersion into light from the light source and traversing the second arm, where the second arm is the other of the sample arm and reference arm. The second amount of dispersion is larger than the first amount of dispersion. The processing unit processes an interferometry signal to perform OCT, where the interferometry signal represents a superposition of the light from the first arm and the light from the second arm.

Abstract: A technique for optical coherence tomography is provided. As to a device aspect of the technique, an imaging device comprises a base defining a rotation axis, a scanning and focusing assembly mounted to the base for rotation about the rotation axis, and a drive unit for rotationally driving the scanning and focusing assembly about the rotation axis. The scanning and focusing assembly includes a focusing device for focusing a beam of imaging radiation to produce a focused beam of imaging radiation having a focus, a scanning member for scanning the beam of imaging radiation, and a controller coupled to the drive unit and the scanning member and configured to control the scanning member to cause movement of the focus along a predetermined trajectory with respect to the scanning and focusing assembly.

Abstract: In certain embodiments, a device for optical coherence tomography (OCT) includes a signal detection device and a computer arrangement. The signal detection device is designed to detect an interference signal (G(?)) for an object to be imaged in an optical frequency range (?). The computer arrangement is designed to determine intermediate signals (G1(k), G2(k)) in a spatial frequency range (k) from the intermediate interference signal (G(?)), whereby each of the intermediate signals (G1(k), G2(k)) is dispersion-compensated for a different depth (z1, z2) of the object. A locally resolved image signal (FFT1, FFT2) is determined for each of the intermediate signals (G1(k), G2(k)) by applying a Fourier transformation to the particular intermediate signal (G1(k), G2(k)). A tomography signal (G(z)) is determined from the image signals (FFT1, FFT2).

Abstract: A technique for optical coherence tomography is provided. As to a device aspect of the technique, an imaging device comprises a base defining a rotation axis, a scanning and focusing assembly mounted to the base for rotation about the rotation axis, and a drive unit for rotationally driving the scanning and focusing assembly about the rotation axis. The scanning and focusing assembly includes a focusing device for focusing a beam of imaging radiation to produce a focused beam of imaging radiation having a focus, a scanning member for scanning the beam of imaging radiation, and a controller coupled to the drive unit and the scanning member and configured to control the scanning member to cause movement of the focus along a predetermined trajectory with respect to the scanning and focusing assembly.

Abstract: In certain embodiments, a device for optical coherence tomography (OCT) includes a signal detection device and a computer arrangement. The signal detection device is designed to detect an interference signal (G(?)) for an object to be imaged in an optical frequency range (?). The computer arrangement is designed to determine intermediate signals (G1(k), G2(k)) in a spatial frequency range (k) from the intermediate signal (G(?)), whereby each of the intermediate signals (G1(k), G2(k)) is dispersion-compensated for a different depth (z1, z2) of the object. A locally resolved image signal (FFT1, FFT2) is determined for each of the intermediate signals (G1(k), G2(k)) by applying a Fourier transformation to the particular intermediate signal (G1(k), G2(k)), A tomography signal (G(z)) is determined from the image signals (FFT1, FFT2).

Abstract: In a process for optical coherence tomography a plurality of first OCT slice images, in each first slice image representing a different slice of an object, are recorded. Subsequently a reference figure that is representative of the three-dimensional contour of at least one structural feature of the object in a given three-dimensional coordinate system is ascertained by feature recognition of the at least one structural feature in the first slice images. Then a plurality of second OCT slice images, each second slice image representing a different slice of the object, are recorded. At least a fraction of the second slice images are displaced in the coordinate system until each second slice image is in feature overlap with the reference figure. Lastly, a set of three-dimensional OCT image data is generated at least from the feature-overlapped second slice images.

Abstract: In certain embodiments, a device for optical coherence tomography (OCT) includes a signal detection device and a computer arrangement. The signal detection device is designed to detect an interference signal (G(?)) for an object to be imaged in an optical frequency range (?). The computer arrangement is designed to determine intermediate signals (G1(k), G2(k)) in a spatial frequency range (k) from the interference signal (G(?)), whereby each of the intermediate signals (G1(k), G2(k)) is dispersion-compensated for a different depth (z1, z2) of the object. A locally resolved image signal (FFT1, FFT2) is determined for each of the intermediate signals (G1(k), G2(k)) by applying a Fourier transformation to the particular intermediate signal (G1(k), G2(k)). A tomography signal (G(z)) is determined from the image signals (FFT1, FFT2).

Abstract: A spectroscopic instrument includes a first optical component for spatial spectral splitting of a polychromatic beam of light impinging onto the first optical component, an objective, which routes various spectral regions of the split beam of light onto differing spatial regions, and a sensor, situated downstream of the objective in the beam path of the beam of light, with a plurality of light-sensitive sensor elements. The sensor elements are arranged in the beam path of the split beam of light in such a manner that each sensor element registers the intensity of a spectral sector of the beam of light and the medians of the spectral sectors are situated equidistant from one another in the k-space, where k denotes the wavenumber.

Abstract: In certain embodiments, a device for optical coherence tomography (OCT) includes a signal detection device and a computer arrangement. The signal detection device is designed to detect an interference signal (G(?)) for an object to be imaged in an optical frequency range (?). The computer arrangement is designed to determine intermediate signals (G1(k), G2(k)) in a spatial frequency range (k) from the intermediate signal (G(?)), whereby each of the intermediate signals (G1(k), G2(k)) is dispersion-compensated for a different depth (z1, z2) of the object. A locally resolved image signal (FFT1, FFT2) is determined for each of the intermediate signals (G1(k), G2(k)) by applying a Fourier transformation to the particular intermediate signal (G1(k), G2(k)). A tomography signal (G(z)) is determined from the image signals (FFT1, FFT2).

Abstract: An apparatus for optical swept-source coherence tomography comprises a spectrally tuneable source for emitting coherent light, and a detector for acquiring the intensity of remitted light backscattered from an object irradiated with the coherent light of the source. Further, the apparatus comprises a control device, which is set up to control the light source and the detector in such a way that the detector performs intensity acquisitions in accordance with a defined number of measurements, while the light source is tuned, the control device further being set up, for the purpose of altering the measurement depth or/and the axial resolution of the tomography, to alter the defined number of measurements or/and a spectral measurement bandwidth, within which the detector performs the intensity acquisitions.

Abstract: The invention relates to an arrangement for interferometry, including a light source for generating coherent radiation, a detector and a beam splitter for dividing the radiation generated by the light source. The radiation is divided into a sample arm in which a sample to be examined can be positioned and a reference arm. An optical reference element, which is partially transparent to the radiation, reflects a part of the radiation to the detector and behind which the sample to be examined can be positioned is disposed in the beam path of the sample arm.