Carl Zeiss Meditec Gmbh

Carl Zeiss Meditec Ag

Exalos Ag

Rainer Leitgeb

Alexandre R Tumlinson

Abhishek Kumar

Adolf Friedrich Fercher

Manfred Dick

Roland Bergner

Ralf Ebersbach

Marcus Pierre Dülk

Thomas Pabst

Cedric Blatter

Michael Niederleithner

Laurin Ginner

A method of controlling a semiconductor-laser-diode-based SS-interferometer system (SS=swept source), for a wide range of application suitable for use in ophthalmology, for example for imaging and for determining biometric measurement values of the eye. In a method according to the invention, by application of periodic current modulation, the operation of single semiconductor laser diode is designed such that a highly coherent spectral laser line can be adjusted with a highest possible repetition rate over a wide wavelength range. The parameters: center wavelength, sweep rate, sweep range, optical power in the eye and coherence length are adjusted such that the method is suitable for imaging and biometric applications via whole-eye scans. A semiconductor-laser-diode-based SS-interferometer system is provided, for biometric measuring of the eye. Embodiments are based for example on optical, coherence tomographic scan images. Applications lie in ophthalmological diagnostics, treatment and the preparation of surgical procedures and follow-up thereof.

Method for controlling a semiconductor-laser-diode-based SS-interferometer system

A method for compensating the artifacts generated by moving measurement objects in measurement signals of swept-source OCT systems by moving measurement objects. Signal reconstruction is implemented without the aid of additional reference signals in respect of the movement of the measurement object and only by way of especially adapted algorithms. Example methods relate firstly to the especially adapted, Fourier transform-based algorithms for processing the captured measurement signals and secondly to the measurement signals to be captured, in particular to the optical coherence interferometry-based measurement systems used for the production thereof. Although the proposed method is provided for applications in ophthalmology in particular, it can be used, in principle, wherever signals reflected by curved surfaces or backscattered from structures are analyzed.

Method for compensating the artifacts generated by moving measurement objects in measurement signals of swept-source OCT systems

A source module suitable for an optical coherence tomography system. The source module comprises a source operable to emit a divergent, source output beam either of circular cross-section (e.g. as output by a vertical cavity surface emitting laser) or of elliptical cross-section (e.g. as output by an edge-emitting semiconductor laser or diode). Collimation optics are provided to convert the source output beam into a non-divergent, collimated beam of elliptical cross-section having a major axis and a minor axis. A cylindrical lens is arranged with its plano axis aligned with the major axis of the elliptical collimated beam and its power axis aligned with the minor axis of the elliptical collimated beam so as to form a line focus extending along the major axis of the elliptical collimated beam.

Source module and optical system for line-field imaging

Systems and methods for sub-aperture correlation based wavefront measurement in a thick sample and correction as a post processing technique for interferometric imaging to achieve near diffraction limited resolution are described. Theory, simulation and experimental results are presented for the case of full field interference microscopy. The inventive technique can be applied to any coherent interferometric imaging technique and does not require knowledge of any system parameters. In one embodiment of the present application, a fast and simple way to correct for defocus aberration is described. A variety of applications for the method are presented.

Systems and methods for sub-aperture based aberration measurement and correction in interferometric imaging

Systems and methods for sub-aperture correlation based wavefront measurement in a thick sample and correction as a post processing technique for interferometric imaging to achieve near diffraction limited resolution are described. Theory, simulation and experimental results are presented for the case of full field interference microscopy. The inventive technique can be applied to any coherent interferometric imaging technique and does not require knowledge of any system parameters. In one embodiment of the present invention, a fast and simple way to correct for defocus aberration is described. A variety of applications for the inventive method are presented.

Methods for determining improving quantitative and qualitative motion contrast information collected with optical coherence tomography (OCT) data are presented. In one embodiment, flow within a cross-sectional area of a sample is calculated independent of the Doppler and en face angles using a bidirectional OCT system. In another embodiment, motion contrast images are improved by averaging motion contrast information collected from a bidirectional OCT system.

Systems and methods for bidirectional functional optical coherence tomography

A device for the interferometric measurement of a sample, in particular the eye, including an interferometer arrangement with a first measurement beam path, through which a measurement beam falls onto the sample, and a first reference beam path, through which a reference beam runs, which is applied to the measuring beam for interference. The interferometer arrangement includes a second measuring beam path and/or second reference beam path. The optical path lengths of the second measuring beam path and/or second reference beam path are different from one of the first beam paths. The wave length difference is selected according to a distance of two measuring areas which are arranged at a distance in the depth direction of the sample.

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Vienna, Austria

Rainer Leitgeb