摘要:
The eye is illuminated by a variable laser light source with a measurement range corresponding to the eye length, wherein the focus of the laser beam in the eye can be shifted laterally and/or axially by an adjustment mechanism, and the light fractions back-scattered from the sample are captured via an interferometer by a data acquisition unit and forwarded to a data processing unit. In the data processing unit, an OCT whole-eye scan is combined with at least one or several further overlapping tomographic part-eye or whole-eye scans. Reference information is used to register the first whole-eye scan with the further part-eye or whole-eye scans, and the combined whole-eye scan is evaluated and/or displayed on a user surface.
摘要:
A system for the improved imaging of eye structures based on optical coherence tomography. The system includes an interferometric measuring arrangement, which has an optical element arranged in the measurement arm or reference arm for influencing the polarization state of the light before the light is interferometrically superimposed, a scanning unit arranged in the measurement arm for implementing OCT scans, a detector for recording the produced interference pattern, and an evaluating and documenting unit. At least two different polarization states of the light are produced. The interference patterns produced in the interferometric measuring arrangement are recorded and forwarded to the evaluating and documenting unit which reconstructs OCT scans from the transmitted interference patterns, combines the OCT scans, and presents and/or stores the resulting OCT signals. The system can be used for pachymetry in addition to the pre- and post-operative imaging for analysis and measurement.
摘要:
An article for use in an OCT method, the article comprising a solid substrate and nanoparticles dispersed in or on the substrate in at least one light transmissive portion of the article such that the nanoparticles result in an increased extinction of the light transmissive portion along a transmission direction of the light transmissive portion compared to the substrate being free of nanoparticles. The extinction of the light transmissive portion along the transmission direction is less than 6, wherein the extinction is defined as a negative decadic logarithm of a ratio of an intensity of light which is transmitted through the light transmissive portion to an intensity of light which is incident on the light transmissive portion, wherein the light is in at least one of a visible and a near infrared wavelength range.
摘要:
A short coherence interferometer apparatus for measuring multiple axially spaced regions of a specimen, in particular the eye, which has at least one measuring beam path, through which multiple individual measuring beams are incident on the specimen, and one reference beam path, through which a reference beam runs, with which the individual measuring beams are superimposed and brought into interference. The individual measuring beams are axially offset to one another upon incidence on the specimen by an amount which is adapted to the axial spacing. The interferometer apparatus superimposes each individual measuring beam with the reference beam in an interfering manner and conducts it to a detector associated with the particular individual measuring beam. The individual measuring beams are combined into a mixture in which they have varying phasing in the superposition with the reference beam.
摘要:
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 k0 and at least one receiver for the light dissipated from the sample, wherein the sample is illuminated on the sample surface by a measurement beam having a diameter D by way of a coupling device. The light source has a spectral line width of δk
摘要:
For the model-based determination of the biometry of eyes, the eye is illuminated by a light source via a scanning unit, the focus of the measuring light beam in the eye is moved or shifted laterally and/or axially via an adjusting device and the light fractions back-scattered by the boundary surfaces and from the tissue of the eye via an interferometer are detected by a sensor and relayed to a control and evaluation unit by which a parametric eye model which describes at least two boundary surfaces present in the eye is adapted to the scan or scans. The invention relates to the field of ophthalmology and serves in particular for the optical determination of the biometry of eyes by application of two-dimensional optical coherence tomography images. However, the method is not limited to the use of coherence tomography nor to the utilisation of optical measurements.
摘要:
A line scan imager is used to determine the motion of a subject. Each line of image data from the line scan imager is compared with a reference image. The location of a matching line in the reference image reveals the displacement of the subject. The current subject displacement can be determined based on each line of image data. The resulting displacement information can be used to correctly place other optical beams on the subject. The method can be applied to tracking the human eye to facilitate measurement, imaging, or treatment with a beam of optical radiation.
摘要:
Selection of an appropriate intraocular lens (IOL) and/or the applicable surgical parameters for optimizing the results of refractive procedures on the eye. Features of the IOL are crucial for the selection and/or adjustment of the optimal IOL, but so is the IOL selection method (and parameters) from a surgical perspective. For the method, corresponding output parameters are determined from predetermined, estimated, or measured input parameters and/or their mean values, wherein at least two input parameters are varied with one another and which have at least one input parameter as a distribution function. The resulting function is optimized by means of corresponding target values and the determined distribution function of one or more output parameters is used as a decision aid. The present solution is used for selecting an appropriate IOL and/or the applicable surgical parameters and is applicable in the field of eye surgery for implanting IOLs.
摘要:
An optical coherence tomography device is disclosed for improved imaging. Reduced levels of speckle in the images generated by the device are obtained by forming a B-scan from a plurality of A-scans, wherein each resolution cell of the B-scan is generated through compounding of a subset of the A-scans and wherein at least some of the subset of A-scans are separated by at least half the diameter of a speckle cell both tangent to and orthogonal to the B-scan at that cell.
摘要:
Imaging systems are provided allowing examination of different object regions spaced apart in a depth direction by visual microscopy and by optical coherence tomography. An axial field of view and a lateral resolution is varied depending on which object region is examined by the imaging system. The proposed imaging systems are in particular applicable for thorough examination of the human eye.