Carl Zeiss Meditec Gmbh

Carl Zeiss Meditec Ag

Tilman Schmoll

Matthew J Everett

Alexandre R Tumlinson

Utkarsh Sharma

Nathan Shemonski

Siddharth Srivastava

Michael Kempe

Xing Wei

Harihar Narasimha-Iyer

Mary K Durbin

Systems and methods for improved interferometric imaging are presented. One embodiment is a partial field frequency-domain interferometric imaging system in which a light beam is scanned in two directions across a sample and the light scattered from the object is collected using a spatially resolved detector. The light beam could illuminate a spot, a line or a two-dimensional area on the sample. Additional embodiments with applicability to partial field as well as other types of interferometric systems are also presented.

Frequency-domain interferometric based imaging systems and methods

An OCT system for generating images of an anterior or posterior segment of an eye is described. The system includes a light source, a controller, optics, a detector, and a processor. The light source generates a beam of light and is capable of operating in a posterior or an anterior segment imaging mode. In the posterior segment imaging mode, light source outputs light with a first spectral bandwidth of less than 120 nm and including wavelengths between about 1060 to 1070 nm. In the anterior segment imaging mode the light source outputs light with a second spectral bandwidth that is larger than 120 nm. The controller enables switching between the posterior or anterior segment imaging mode.

1060 nm wavelength range-based optical coherence tomography (OCT) system for anterior/posterior segment imaging of an eye

Various systems and methods for sequential angle illumination to achieve ultra-high resolution optical coherence tomography (OCT) images. One example OCT system includes a light source, a beam divider, sample arm optics, a detector, and a processor. The light source generates a light beam to illuminate the sample. The beam divider separates the light beam into reference and sample arms. The sample arm optics sequentially illuminates a location in the sample with the light beam from different angles. The detector receives light returned from the reference arm and the sample illuminated at each angle and generates signals. The processor combines the signals to generate an image, which has a transverse resolution that is higher than the transverse resolution achieved from the signal generated from a single angle.

Systems and methods for improved OCT measurements

Various balanced detection systems which reduce alignment requirements of free space optics based balanced detection configurations are discussed. One example system includes a light source, a beam divider, sample optics, return optics, and a processor. The light source generates a light beam. The beam divider separates the light beam into reference and sample arms. The sample optics deliver the light beam in the sample arm to a light scattering object to be imaged. The return optics direct light to a balanced detection system, which has a balanced detection beam divider for combining light scattered from the object and light from the reference arm and directing the combined light into two detection channels and two detectors for collecting the combined light in the two detection channels and generating signals in response thereto. The processor processes the signals and generates image data of the object based on the processed signals.

Balanced detection systems

Techniques are introduced to improve the ability of OCT to determine more accurately the nature of the flow of fluids in the eye, including faster measurements of the flow and a method to reduce geometric uncertainties due to eye movements.

High temporal resolution doppler OCT imaging of retinal blood flow

Improved line-field imaging systems incorporating planar waveguides are presented. In one embodiment the optics of the system are configured such that a line of light on the light scattering object is imaged to the planar waveguide in at least one dimension. Embodiments where the waveguide incorporates a beamsplitter of an interferometer, where the beam divider and waveguide are referenced to one or more common surfaces, and wherein the source and waveguide are optically coupled, are also considered. In another embodiment, the planar waveguide is in contact or close proximity to the light scattering object.

Line-field imaging systems and methods incorporating planar waveguides

High temporal resolution Doppler OCT imaging of retinal blood flow

Embodiments herein include swept-source interferometric imaging systems employing arbitrary sweep patterns in which a swept-source is swept over a continuous spectral range where the variation of wavelength over time is noncontinuous. Embodiments include sweep patterns that result in reduction of signals from moving scatterers and where the sweep is synchronized with the dead time of the camera.

Swept source interferometric imaging systems and methods

Systems and methods are presented for acquisition and processing of spectrally dispersed illumination optical coherence tomographic data. Light from a source is distributed spectrally on the sample, and each acquisition simultaneously provides partial spectral interference information from multiple locations in the sample. Thus for a given spatial point, a single observation will be of a partial spectrum A-scan. When multiple partial spectrum A-scan observations are made at the same point by shifting the spectrum of light on to the tissue, the point can be observed by the entire broadband spectrum of the light source, thereby making it possible to create a full axial resolution A-scan.

Systems and methods for spectrally dispersed illumination optical coherence tomography

Methods for analyzing and visualizing OCT angiography data are presented. In one embodiment, an automated method for identifying the foveal avascular zone in a two dimensional en face image generated from motion contrast data is presented. Several 3D visualization techniques are presented including one in which a particular vessel is selected in a motion contrast image and all connected vessels are highlighted. A further embodiment includes a stereoscopic visualization method. In addition, a variety of metrics for characterizing OCT angiography image data are described.

Analysis and visualization of OCT angiography data

Systems and methods for improved acquisition of ophthalmic optical coherence tomography data are presented, allowing for enhanced ease of use and higher quality data and analysis functionality. Embodiments include automated triggering for detecting and initiating collection of OCT ophthalmic data, an automated technique for determining the optimal number of B-scans to be collected to create the highest quality image and optimize speckle reduction, automated review of fundus images collected with an adjunct imaging modality to guide the OCT data collection, a single scan protocol in which a large field of view is collected with HD B-scans embedded at different locations depending on automated analysis of either a fundus image or sparse OCT scan, and various scan configurations for imaging eyes with large axial depth range.

Systems and methods for improved acquisition of ophthalmic optical coherence tomography data

Systems and methods for faster acquisition and processing of OCT image data are presented. In one embodiment of the present invention, an OCT system is operated in two different acquisition modes of different axial resolutions to allow for efficient collection of OCT Angiography data while also collecting high resolution OCT data. In another embodiment, a reduced subset of a collected data set is used for OCT Angiography data analysis. In another embodiment, a sweep of a swept-source laser is split into different spectral components covering different transverse locations on the sample. A further aspect includes the ability to process all or a portion of collected OCT data with one motion contrast technique before or while a second set is processed using a different motion contrast technique.

Systems and methods for faster optical coherence tomography acquisition and processing

Swept source designs that eliminate or significantly reduce artifacts in optical coherence tomography are presented. One embodiment of the present invention is a source design that frequency shifts the coherence revival interference signal to a frequency larger than the A/D detection bandwidth or the post-processing bandwidth. In another embodiment, the introduced frequency shift is large enough to introduce a Doppler shift of the modes of the laser, which causes a blurring of the comb function, and thus eliminates or reduces mode hopping. In another embodiment, adjusting the cavity optical path length prior to data acquisition depending on the given optical layout configuration to reduce or eliminate coherence revival artifacts is described.

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Dublin, CA, United States of America

Tilman Schmoll