Patent application number | Description | Published |
20110109913 | SHORT COHERENCE INTERFEROMETRY FOR MEASURING FOR MEASURING SPACINGS - A short coherence interferometer for measuring several axially spaced-apart regions of a sample, especially of an eye, which has a measuring optical path, through which the measuring radiation falls on the sample, a tunable interferometer for the axial, relative retardation of parts of the radiation, wherein the axial relative retardation is assigned to the axial spacing of the regions and a detector for producing an interference signal from interfering measurement radiation, scattered or reflected back from the sample as sample radiation. The tunable interferometer divides the sample radiation into two parts, which are axially relatively retarded and superimposed so as to interfere. During the superimposition, the tunable interferometer forms individual radiations, which represent quadrature components of the sample radiation, and the detector detects the individual radiations. | 05-12-2011 |
20110149245 | OPTICAL COHERENCE REFLECTOMETRY WITH DEPTH RESOLUTION - A device for performing distance measurements on an eye. The device includes an interferometer, focuses at least one measurement beam records backscattered radiation and interferometrically generates a measurement signal displaying structures of the eye by time-domain, spectral-domain or Fourier-domain coherence reflectometry, has an adjustment apparatus for laterally and/or axially displacing the focus in the eye or for varying a polarization state of the measurement beam and has a control apparatus which actuates the interferometer, wherein the control apparatus generates a plurality of A-scan individual signals from the backscattered radiation, combines these to an A-scan measurement signal and actuates the adjustment apparatus for displacing the position of the focus or for varying the polarization while recording the backscattered radiation from which the control apparatus generates the A-scan individual signals is being recorded. | 06-23-2011 |
20110255054 | DEVICE FOR SWEPT-SOURCE OPTICAL COHERENCE DOMAIN REFLECTOMETRY - A device for swept-source optical coherence domain reflectometry (SS OCDR) on moveable samples, particularly human eyes, for obtaining A-scans, having a measuring range according to the sample length and having a laser light source which can be adjusted by a main wave number k | 10-20-2011 |
20110299038 | OPHTHALMOLOGICAL MEASURING SYSTEM AND METHOD FOR CALIBRATING AND/OR ADJUSTING THE SAME - An ophthalmological measuring system, for obtaining biometric data of an eye, provided with the necessary calibration and check devices for monitoring the functionality and the calibration status. The ophthalmological measuring system includes an illumination source for illuminating an eye with light and with a sensor for recording and analyzing back-scattered or reflected light components and a controller. At least one calibration and check system integrated in the ophthalmological measuring system for monitoring the functional and calibration status is provided. A device is also provided which houses the calibration and test structures and which reads off the individual physical data therefrom by an interface. The ophthalmological measuring system is in particular provided for determining biometrical data but can also be used for ophthalmological, dermatological or other devices which require calibration and/or functional checking at regular intervals. | 12-08-2011 |
20130120711 | OCT-BASED OPHTHALMOLOGICAL MEASURING SYSTEM - An ophthalmological measuring system for determining distances and/or for tomographic imaging of ocular structures, based on an OCT method. The measuring system includes a light source with a spectral centroid (λ), an interferometric measuring device, a scanner system, which in addition to the lateral deflection of the sample beam also has axial modulations with a frequency (f) in the sample arm, and a control and evaluation unit. The scanner performs a lateral, two-dimensional deflection of the sample beam with the aid of one or even two separate mirror elements and can in particular have axial modulation amplitudes z | 05-16-2013 |
20130308097 | OPTIMIZED DEVICE FOR SWEPT SOURCE OPTICAL COHERENCE DOMAIN REFLECTOMETRY AND TOMOGRAPHY - Optimized device for swept source optical coherence domain reflectometry and tomography. In the coherence-optical device, light, with the aid of an interferometer, is used for distance-measuring and imaging purposes on reflecting and scattering areas of the human eye. The optimized device according to the invention consists of includes a tunable light source, matched to the sought-after measurement region ZOCT, with a resonator length LR, an interferometric measurement arrangement, a data capturing unit for capturing the light portions scattered back from the sample and a data processing unit. Here the resonator length LR of the tunable light source is matched not only to the sought-after measurement region ZOCT, but also to the entire interferometric measurement arrangement such that disturbance points present in the interferometric measurement arrangement cannot create disturbance signals in the sought-after measurement region ZOCT. | 11-21-2013 |
20140049753 | METHOD FOR MEASURING AN EYE - A method for measuring the axial length of an eye using optical coherence tomography, during which a plurality of A-scans of the OCT measurement are combined to an axial length, taking into account the alignment with which they were obtained, and taking into account the topography of the cornea. The distance of the front of the cornea from the retina is determined using OCT while measuring or controlling the alignment of the measuring device to the eye in that the topography of the front of the cornea is measured or made available. The calculation of an axial length from an A-scan of the OCT takes into account a corneal topography registered to the A-scans and is the basis for an intraocular lens calculation. The invention exhibits an increased tolerance range with regard to an imprecise alignment of the measuring device to the eye. | 02-20-2014 |
20140092363 | PROCESS FOR RELIABLY DETERMINING THE AXIAL LENGTH OF AN EYE - A method for reliably determining the axial length of an eye uses optical coherence tomography (OCT), where the eye is aligned with a fixation mark so that the optical axis of the measuring instrument coincides at least approximately with a visual axis of the eye. The axial length is determined from at least one B-scan taken in an initial AS mode (anterior segment mode) and the axial length is also determined from at least one B-scan taken in a second RS mode (retina segment mode). A resultant reliable axial length of the eye is determined using the axial lengths from the AS and RS modes, where available and where possible, or the process is ended without a resultant axial length. | 04-03-2014 |
20140268057 | DEVICE FOR SWEPT SOURCE OPTICAL COHERENCE DOMAIN REFLECTOMETRY - A device for swept-source optical coherence domain reflectometry (SS OCDR) on moveable samples, particularly human eyes, for obtaining A-scans, having a measuring range according to the sample length and having a laser light source which can be adjusted by a main wave number k | 09-18-2014 |