WO2013079214A1

WO2013079214A1 - Microscopy system for eye examination and oct system

Info

Publication number: WO2013079214A1
Application number: PCT/EP2012/004954
Authority: WO
Inventors: Christoph Hauger
Original assignee: Carl Zeiss Meditec Ag
Priority date: 2011-11-30
Filing date: 2012-11-30
Publication date: 2013-06-06
Also published as: DE102011119899A1

Abstract

The invention relates to a microscopy system for eye examination, comprising: imaging optics for generating a first image in a first image plane of the imaging optics; an OCT system for detecting OCT data. The OCT system has a light source. The microscopy system further comprises illumination optics in order to deflect light from the light source onto the object plane. The microscopy system has an OCT operating mode in which the illumination optics generate an OCT optical path of the light from the light source in order to scan a scanning region of the OCT optical path. The microscopy system further comprises an incident light operating mode in which the illumination optics generate an incident light optical path of the light from the light source in order to generate the first image. The incident light optical path illuminates the object plane in parallel, or the incident light optical path has a divergence or convergence in the object plane, which is equivalent to a focus distance from the object plane which is larger than 2 cm.

Description

MICROSCOPY SYSTEM FOR EYE EXAMINATION AND OCT SYSTEM

Technical Field The present invention relates to an ocular microscopy system having an OCT system. In particular, the present invention relates to a microscopy system that can obtain microscopic images and OCT data from the anterior and / or retina of the eye. Furthermore, the present invention relates to such a microscopy system, which is further configured to generate dark field, and / or phase contrast images from the front of the eye.

Brief description of the prior art

Eye examinations use OCT systems based on the principle of optical coherence tomography. With today's OCT systems, sectional or volume images of structures within a biological tissue can be obtained with an axial resolution down to the order of one micron. The penetration depth of the light can be about 1 to 3 millimeters. The light sources used are typically broadband superluminescent diodes or laser light sources. The use of OCT has already enabled imaging rates that allow near real-time observation of samples.

The achievable resolution of OCT systems has led to a rethink in ophthalmology, as ophthalmologists can now obtain information they previously only knew from the textbook. The use of OCT makes it possible to detect even the smallest changes in tissue parts at an early stage, which was difficult or even impossible with other methods.

High demands on the imaging of tissue parts of the eye are made in cataract surgery. In carrying out this operation, tissue remnants from the capsule bag of the eye lens must be removed as completely as possible in order to avoid later complications for the patient. However, these tissue remnants are difficult to recognize due to their high transparency in a surgical microscope. However, it has been shown that in cataract surgery imaging of the anterior region of the eye with surgical microscopes can not always be achieved with sufficiently high contrast.

It is therefore an object to provide a microscopy system that allows a more efficient eye examination. Embodiments provide a microscopy system for eye examination, comprising: imaging optics for generating a first image in a first image plane of the imaging optic from a region of an object plane of the imaging optic through a first observation beam path of the imaging optic; an OCT system for acquiring OCT data, the OCT system having a light source and an interferometer; and illumination optics for directing light of the light source to the object plane; wherein the microscopy system has an OCT mode of operation, in which the illumination optics generates an OCT beam path of the light to scan a scanning range of the OCT beam path, and wherein the microscopy system further comprises an incident light operating mode in which the illumination optics generates an incident light beam path of the light for generating the first image; wherein the reflected light beam path illuminates the object plane in parallel; or wherein the reflected light beam path in the object plane has a divergence or convergence corresponding to a focal distance from the object plane greater than 2 cm.

As a result, a microscopy system is obtained with which a source of the OCT system can be used simultaneously for incident light illumination and for imaging with the observation beam path. In particular, a microscopy system with reflected-light illumination can be obtained, which permits imaging with an increased contrast. Due to the increased contrast, even small and highly transparent tissue residues in the capsular bag can be easily recognized. This in particular allows cataract surgery to be performed so as to reduce the risk of later complications for the patient.

The microscopy system can be designed such that the front region of an eye to be examined can be arranged in the object plane. The anterior region of the eye may include the cornea, the anterior chamber of the eye, the iris and the natural lens.

The OCT system may be a Time Domain OCT (TD-OCT), or a Frequency Domain OCT (FD-OCT). The Frequency Domain OCT system can be, for example, a Spectral Domain OCT System (SD-OCT) or a Swept Source OCT System (SS-OCT). A diameter of the OCT beam path in the scanning region of the OCT beam path may be less than 10 micrometers, less than 5 micrometers, or less than 2 micrometers. During scanning, the OCT beam path performs a raster motion in the scanning area.

The light source may be configured to generate broadband light. A coherence length of the light is inversely proportional to the bandwidth. Bandwidths of the wave packets emitted by the light source may be greater than 30 nm or greater than 50 nm or greater than 100 nm. For example, the light source may comprise a light emitting diode, a superluminescent diode, or a laser. The OCT system and the light source For example, they may be designed for operating wavelengths of 810 nanometers and / or 1310 nanometers.

The reflected light beam path may be configured or configurable such that the light enters the inside of the eye through a pupil of the eye to be examined arranged in the object plane and generates a lighting triangle on the retina. A diameter of the illumination spot may be less than 0.7 millimeters, or less than 0.5 millimeters, or less than 0.1 millimeters, or less than 50 microns, or less than 30 microns, or less than 25 micrometers.

The illumination optics generates the OCT beam path and the reflected light beam path. The illumination optics can consist of one or more of the following optical elements: lenses, cemented elements, mirrors, beam splitters and / or diaphragms. The OCT beam path and the reflected light beam path can each enforce common components of the illumination optics. In other words, the illumination optics can have components that are penetrated by the reflected light beam path and the OCT beam path in each case.

These components penetrated by the two beam paths may comprise an objective lens of the microscopy system. Furthermore, these components can also have one or more optical components, which are arranged in the reflected light beam path and in the OCT beam path between the light source and the objective lens and which each have a positive or negative focal length. These refractive optical components may be, for example, lenses and / or cemented members. The illumination optics can be configured such that it images a light entry of the OCT beam path into the scanning region. Furthermore, the illumination optics can be configured such that it converts a light entry of the reflected light beam path into a parallel, divergent or convergent beam path in the object plane. The imaging and transformation may be dependent on a focal length of the illumination optics. The illumination optics can generate a real or virtual optical image of the light entrance of the reflected light beam path, or image the light entrance of the reflected light beam path to infinity. The reflected light beam path may have a convergence or divergence in the object plane that corresponds to a focal distance from the object plane that is greater than 2 cm. The focal distance may be a distance of a real or virtual focus from the object plane, where the real or virtual focus is an image of the light entrance generated by the illumination optics. The illumination optics can be designed so that the light entry through the illumination optics can be imaged onto the retina of an eye to be examined. The eye to be examined may be legal or have ametropia between -20 dpt and +20 dpt. The light entry may be defined as a location at which light of the reflected light beam path and / or the OCT beam path enters the illumination optical system. The light entrance may be a boundary between a non-imaging and an imaging optical system. The non-imaging optical system may be disposed in the optical path of the light between the OCT system and the light entrance. The non-imaging optical system may be a light guide. The imaging optical system can guide the light from the light entrance to the object plane. The imaging optical system may be the illumination optics. The imaging optical system may generate a real image or a virtual optical image of the light entrance, or image the light entrance to infinity.

At the entrance to the light, a light exit surface of a light guide can be arranged or be arranged. Alternatively or additionally, a field diaphragm of the illumination optical system and / or a focal point of the reflected light beam path and / or the OCT beam path can be arranged at the light entrance.

The illumination optics can be designed such that an image width of a real or virtual image of the light entrance can be varied. The image width can be variable, for example, by a variable focal length of the illumination optics or by a variable distance of the light entrance from a main plane of the illumination optics.

As a result, the illumination optics can be designed such that the position of the scanning region of the OCT beam path is variable along an axis of the OCT beam path. In addition or as an alternative, the illumination optics can thereby be designed such that a convergence or divergence of the reflected light beam path in the object plane can be set.

The reflected light beam path can illuminate the object plane parallel or substantially parallel. In other words, the reflected light beam path in the object plane to planar or substantially planar wavefronts. The reflected light beam path may have a divergence or convergence in the object plane. In other words, the wavefronts in the object plane may deviate from plane wavefronts. This can result in an opening angle of the beam path in the object plane. The aperture angle may include a vertex located at a real or virtual focal point of the reflected light beam path. The real or virtual focal point can be a real or virtual image of the light entrance of the reflected light beam path. The virtual focus may be, for example, a diffraction point, convergence point or divergence point of the reflected light beam path. The real or virtual focus can be arranged such that the light beams of the reflected light beam path can be extrapolated from the object plane to the real or virtual focus. The convergence or divergence of the reflected light beam path in the object plane may correspond to a focal distance from the object plane that is greater than 2 cm, or greater than 5 cm, or greater than 10 cm, or greater than 15 cm. The focal distance can be defined as a distance of a real or virtual focus from the object plane along an axis of the reflected light beam path. A parallel illumination may correspond to a focus distance of infinity.

According to a further embodiment, the reflected light beam path in the object plane has a diameter that is greater than 1 millimeter, or greater than 2 millimeters or greater than 4 millimeters, or greater than 6 millimeters. The reflected light beam path can be fixed in directions perpendicular to its axis by the illumination optics. In other words, the reflected light beam path performs no raster movement.

According to a further embodiment, the OCT system has an optical waveguide which is designed to guide the light of the light source to the light entrance of the reflected light beam path and / or the O CT beam path. The light guide may have a light exit surface through which the light enters the illumination optics. The light exit surface may be arranged at an end portion of the light guide. The light exit surface may be an exposed surface of a core of the light guide. The light guide may be, for example, a step index optical waveguide or a graded index optical waveguide. The light exit surface may be arranged at the light entrance.

According to another embodiment, a core of the optical fiber has a diameter in a range between 3 microns and 9 microns; or in a range between 3 microns and 15 microns; or in a range between 3 microns and 20 microns; or in a range between 3 microns and 50 microns; or in a range between 3 microns and 150 microns.

According to one embodiment, the microscopy system has an image sensor arranged in the first image plane for light detection in incident light operating mode, wherein the microscopy system is configured such that the light detection is suppressed for wavelengths shorter than a cut-off wavelength; wherein the light of the light source has wavelengths longer than the cut-off wavelength; and wherein the cut-off wavelength is greater than 700 nanometers.

Thus, a microscopy system is obtained with which a detection of disturbing light components of the visible wavelength range is suppressed in reflected light mode of operation. The cut-off wavelength may be greater than 1000 nanometers, or greater than 1200 nanometers. According to another embodiment, the cut-off wavelength is in a range between 700 and 1300 nanometers; or in a range between 700 and 800 nanometers; or in a range between 1200 nanometers and 1300 nanometers. The OCT system may have a working wavelength. The cut-off wavelength may be below the operating wavelength of the OCT system. For example, the operating wavelength of the OCT system may be 810 nanometers or 1310 nanometers. The OCT system can have several operating wavelengths. The operating wavelength may be a central wavelength of the light source of the OCT system.

The cut-off wavelength may be a wavelength at which a spectral sensitivity of the light detection of the microscopy system is 50% of a maximum spectral sensitivity of the light detection of the microscopy system. The spectral sensitivity can be defined as a dependence of a sensitivity of the microscopy system on the wavelength of the light of the first and / or second observation beam path in the object plane. The sensitivity can be measured, for example, by an output signal of the microscopy system. The spectral sensitivity can be dependent on a spectral sensitivity of the image sensor and / or on a spectral transmittance of an optical filter which is arranged in the observation beam path between the object plane and the first image plane. The microscopy system may be designed so that at the operating wavelength of the OCT system, the spectral sensitivity of the light detection is at least 60%, or at least 70%, or at least 80% of the maximum spectral sensitivity.

According to a further embodiment, the microscopy system is further configured such that the light detection is suppressed for wavelengths which are greater than a further cutoff wavelength. The further cut-off wavelength may be a wavelength at which the spectral sensitivity of the light detection of the microscopy system is 50% of the maximum spectral sensitivity of the microscopy system. The further cutoff wavelength may be greater than the cutoff wavelength, or greater than a working wavelength of the OCT system. The further cut-off wavelength may be greater than 810 nanometers or greater than 1310 nanometers. The further cut-off wavelength may be greater than 850 nanometers; greater than 1350 nanometers; or greater than 1500 nanometers. For example, the image sensor may have a spectral sensitivity which suppresses light detection of the image sensor of wavelengths below the cut-off wavelength. The cut-off wavelength may then be, for example, a wavelength at which a spectral sensitivity of the image sensor is 50% of a maximum spectral sensitivity of the image sensor. Alternatively or additionally, the image sensor may further suppress the light detection above the further cutoff wavelength. The further wavelength can then For example, be a wavelength at which a spectral sensitivity of the image sensor is 50% of the maximum spectral sensitivity of the image sensor.

Alternatively or additionally, the microscopy system can be configured such that an optical filter is arranged in the observation beam path between the object plane and the first image plane. The optical filter may be an edge filter or a bandpass filter. The optical filter may be configured to suppress transmission of wavelengths shorter than the cut-off wavelength. The cut-off wavelength may be a wavelength at which a spectral transmittance of the optical filter is 50% of a maximum spectral transmittance of the optical filter. In other words, the cut-off wavelength may be a 50% cut-on wavelength of the optical filter. Alternatively or additionally, the optical filter may be designed such that a transmission of wavelengths which are greater than the further cutoff wavelength is suppressed. The further cut-off wavelength may then be a wavelength at which the spectral transmittance is 50% of the maximum transmittance. The microscopy system may be further configured such that the optical filter is removable from the observation beam path for generating images through the first observation beam path with a reflected light source emitting in the visible wavelength range. According to a further embodiment, the microscopy system is designed so that at a constriction of the reflected light beam path: - sin (a) <; wherein D is a diameter of the reflected light beam path at the constriction; and a is an opening angle of the reflected light beam path at the constriction; wherein M has a value of 0.9 millimeters, or has a value of 50 microns, or has a value of 2 microns. The constriction may be a position along the axis of the reflected light beam path, from which the reflected light beam path diverges in the direction of the object plane. The opening angle may be an object-side opening angle, d. H. measured on the downstream side of the constriction.

Thereby, a microscopy system is obtained with which an image of the anterior region of the eye can be obtained with increased contrast. In particular, a red reflex can thereby be obtained which allows the entire pupil to appear in homogeneous transmitted light.

The constriction may be a constriction of the beam path. The constriction may be a convergence point or a focal point of the reflected light beam path. In other words, the constriction may be a position along an axis of the reflected light beam path to which the reflected light beam path converges. The constriction may be in air. Furthermore, the Narrowing be a light exit from the light source or a light guide, which is arranged between the light source and the illumination optics. The constriction may be a light passage area of a diaphragm. Furthermore, the constriction may be a position along an axis of the reflected light beam path at which a diameter of the reflected light beam path transverse to the axis has a minimum. The minimum or the constriction may be arranged between the light entrance of the reflected light beam path and an objective lens of the microscopy system, wherein the reflected light beam path and the first observation beam path pass through the objective lens in each case. The minimum diameter may be a minimum diameter of the sum of all the beams that leave the light source and are directed by the observation optics to the object plane. The minimum diameter can be measured perpendicular to the reflected light beam path.

The opening angle may be a far-field opening angle. The far field can be measured at a distance from a beam waist of the reflected-light beam path, which is, for example, five times or ten times the Rayleigh length.

According to one embodiment, the diameter and the opening angle are determined depending on rays of the reflected light beam emanating from the light source and wholly or at least partially impinge on a circular area in the object plane, which has a diameter of 8 millimeters about the axis of the reflected light beam path. Therefore, according to this embodiment, only those light beams are considered for the determination of the diameter and the opening angle, which, in the case of a maximally opened pupil, enter completely or at least partially into the eye interior of the eye to be examined. According to another embodiment, M has a value of 0.5 millimeters, or a value of 0.1 millimeters, or a value of 30 microns, or a value of 20 microns, or a value of 10 microns, or a value of 5 microns, or a value of 3 microns. In another embodiment, the diameter D is less than 1.5 millimeters, or less than 1 millimeter, or less than 0.5 millimeters, or less than 0.1 millimeters, or less than 50 microns, or less than 20 microns, or less than 10 microns, or less than 5 microns. The diameter D may depend on a working wavelength of the OCT system. The diameter D may be in a range between a minimum diameter of a core of a light guide at which light of the working wavelength can still be coupled into the light guide and a maximum diameter of the core at which light having the working wavelength is still transportable by single mode propagation in the light guide. The light guide can be arranged on the optical path of the light between the OCT system and the light entrance of the reflected light beam path in the illumination optical system; in particular between an optical coupler of the OCT system and a Light entry of the reflected light beam path. The light guide may be a single-mode optical fiber for one or more operating wavelengths of the OCT system. Alternatively, the optical fiber may be a multimode optical fiber for the one or more operating wavelengths.

According to another embodiment, the opening angle a is less than 50 degrees, or less than 45 degrees, or less than 30 degrees, or less than 20 degrees, or less than 15 degrees, or less than 5 degrees, or less than 1 degree, or less than 0.5 degrees, or less than 0.1 degrees. The opening angle a can be twice an acceptance angle of an end section of the light guide, wherein the end section has a light exit surface through which the light is emitted into the illumination beam path.

According to a further embodiment, the microscopy system is designed so that a radial distance of an axis of the OCT beam path and / or an axis of the reflected light beam path is adjustable relative to an optical axis of the illumination beam path.

According to a further embodiment, the microscopy system further comprises: an actuator which is attached to a component of the illumination optics and / or to a light guide, wherein the light guide guides the light to the illumination optics or to a light entry into the illumination optics; and a control unit connected to the actuator; wherein a control of the actuator by the control unit, a radial distance of an axis of the OCT beam path and / or a radial distance of an axis of the reflected light beam path is adjustable relative to an optical axis of the illumination optical system.

This provides a microscopy system that can provide various positions of light entry for the OCT beam and for the incident light beam. In particular for OCT images of the retina, an alignment of the axis of the OCT beam path along the optical axis of the illumination optics may be advantageous. An off-axis course of the axis of the reflected light beam path relative to the optical axis of the illumination optical system can allow an alignment of the axis of the reflected light beam path along the axis of the first observation beam path in the object plane.

The radial distance relative to the optical axis may be a length of a vector that is radial to the optical axis. The axis of the reflected light beam path and / or the axis of the OCT beam path can be aligned parallel to the optical axis of the illumination optical system in the objective lens and / or at the light entrance of the respective beam path.

The illumination optics can have multiple optical axes. The optical axis of the objective lens may be an optical axis of the illumination optics. The optical axis of Illumination optics may have an angled course. The radial distance of the OCT beam path relative to the optical axis of the illumination beam path can be measured at the light entrance of the OCT beam path and / or in the objective lens. The radial distance of the reflected light beam path relative to the optical axis of the illumination beam path can be measured at the light entrance of the reflected light beam path and / or in the objective lens. If the light entrance is an extended area, the distance relative to the optical axis may be a minimum distance between a point in the respective light entrance and the optical axis. The actuator may be attached to an end portion of the light guide, with the end portion assigning the illumination optics. The component of the illumination optics may comprise one or more lenses or cemented elements. The component of the illumination optics can be displaceable together with the light guide. The actuator may be configured so that a radial distance of a light exit surface of the optical waveguide is adjustable relative to the optical axis of the illumination optical system. The light exit surface may be a surface at which the light is emitted from the light guide into the illumination optics. The actuator may be configured such that the axis of the OCT beam path is aligned with the optical axis of the illumination optical system or extends on it. The actuator may be configured such that the radial distance of the reflected light beam path has a greater value than the radial distance of the OCT beam path.

According to a further embodiment, the microscopy system further comprises: a light guide, which guides the light of the light source to a light entrance of the OCT beam path into the illumination optical system; and a further optical fiber, which leads the light of the light source to a light entrance of the reflected light beam path into the illumination optical system.

A first end portion of the light guide and a first end portion of the further light guide may each be arranged on an optical coupler coupler, on a beam splitter or on an optical switch. A second end section of the light guide can be arranged at a light entrance of the reflected light beam path, and a second end section of the further light guide can be arranged at a light entry of the OCT beam path. The light entry of the reflected light beam path and the light entry of the OCT beam path may have a different position. In particular, a radial distance of the light entrance of the reflected light beam path relative to the optical axis of the illumination optical system can be greater than a radial distance of a light entry of the OCT beam path. The light entry of the OCT beam path can be aligned on the optical axis of the illumination optics, in particular, the light entry of the O CT beam path can lie on the optical axis of the illumination optics.

According to a further embodiment, the microscopy system comprises an optical switch, which is designed so that a light path of the light in the light guide and / or a light path of the light in the further light guide can be unlocked or blocked. By actuating the optical switch, the microscope system can be switched between the incident-light operating mode and the OCT operating mode. The optical switch can be connected to a control unit of the microscopy system.

According to a further embodiment, the illumination optical system further comprises focusing optics, wherein the OCT beam path passes through the focusing optics and the reflected light beam path bypasses the focusing optics; or wherein the OCT beam path bypasses the focusing optics and the reflected light beam passes through the focusing optics.

This makes it possible to simultaneously position the scanning region of the OCT beam path in the front region of the eye and to illuminate the object plane with the reflected light beam path.

The focusing optics can be arranged between a light entry of the OCT beam path and the illumination optics; or be arranged between a light entrance of the reflected light beam path and the illumination optics.

According to a further embodiment, in the object plane an axis of the reflected light beam path and / or an axis of the OCT beam path with an axis of the first observation beam path at an angle which is less than 6 degrees, or less than 4 degrees.

By an angle of incidence of less than 6 degrees, it is possible to generate a red reflex through the first imaging beam path, which illuminates the entire pupil in homogeneous transmitted light.

According to a further embodiment, in the object plane, the axis of the reflected light beam path and / or the axis of the OCT beam path with an axis of the first observation beam path forms an angle that is less than 3 degrees, less than 2 degrees, or less than 1 degree.

According to a further embodiment, the imaging optics has a first contrast element, which is arranged in a first intermediate plane of the first observation beam path, wherein the first intermediate plane is arranged between the object plane and the first image plane; wherein the first contrast element is designed so that light, which on a central Area of a cross section of the first observation beam path within the first intermediate plane is incident: (a) absorbed more than in the first intermediate plane outside the central area; and / or (b) undergoes a phase shift that is different than a phase shift in the first intermediate plane outside the central region.

This provides a microscopy system that allows for improved phase-contrast or dark-field imaging of the anterior region of the eye.

The microscopy system may have a second observation beam path, which images the area of the object plane into a second image plane of the imaging optics. The microscopy system may further include a second contrast element disposed in a second intermediate plane of the second observation beam path. The second intermediate plane may be arranged between the object plane and the second image plane. The second contrast element may be designed accordingly, as the first contrast element with respect to the absorption and / or phase shift of light, which impinges on a second central region in the second intermediate plane.

The first intermediate plane may be arranged between an objective lens and the first image plane or a first zoom system. The same can apply to the second intermediate level. The imaging optics can be configured such that beams which leave the object plane as plane wavefronts in the direction of the axis of the first observation beam path are focused by the imaging optics into a point of the first intermediate plane. Accordingly, the imaging optics can be configured such that beams which leave the object plane as a planar wavefront in the direction of the axis of the second observation beam path are focused by the imaging optics into a point of the second intermediate plane. The intermediate planes may be planes which are optically conjugate to the retina of the eye, or optically conjugate to a region of the retina in which one or more illumination spots produced by the illumination optics are located. The imaging optics may have a variable focal length, so that in eyes to be examined, which have a refractive error between -20 D and +20 D, by varying the focal length, the intermediate plane is optically conjugate to the retinal plane adjustable.

The first and second central regions may each be configured to at least partially cover images generated by the illumination spots on the retina in the intermediate planes.

The phase shift that the light undergoes in the central regions within the first and second intermediate planes may be adjusted or settable depending on a phase shift that creates the objects to be observed in the object region. In particular, the phase shift can be set so that the phase shift of the scattered light relative to the phase shift of the unscattered light is such that the scattered light is weakened as much as possible by interference with the unscattered light. As a result, in the image formed in the image plane, the objects to be observed may appear dark against a light background.

For example, a phase shift of light, in the central areas, may be +/- 90 degrees or +/- 45 degrees or +/- 22.5 degrees relative to light outside the central areas, or in a surrounding area around the central areas.

The contrast element may be configured to be transparent or substantially transparent to light appearing on the first or second intermediate plane outside the first and second regions, and / or to produce no or substantially no phase shift.

According to a further embodiment, the first and / or second central regions covers a penetration point of the axis of the first and / or second illumination beam path in the first and / or second intermediate plane. The first central region and / or the second central region may comprise regions of the beam cross section of the respective observation beam path which lie within a circle around the piercing point, the diameter of the circle being less than 50% or less than 30% of the diameter of the respective cross section of the observation beam path.

The first central area and the second central area may in particular be circular areas. The first and / or the second contrast element may be configured such that light rays which leave the object plane at a smaller angle than a minimum scattering angle relative to the axis of the first or second observation beam path strike the first or the second central region. The imaging optics may be designed such that light beams which leave the object plane of the imaging optics at a greater angle than the minimum scatter angle relative to the axis of the first and the axis of the second observation beam path do not strike any of the central areas. According to a further embodiment, the illumination optical system also has a deflection unit, which is arranged in the OCT beam path.

The microscopy system may be designed so that the reflected light beam passage passes through the deflection unit or that the reflected light beam path bypasses the deflection unit. Further For example, the microscope system may be configured such that the deflection unit is deactivated in the incident-light operating mode.

According to a further embodiment, the illumination optics has a variable focal length; the microscopy system further comprising a focal length control unit connected to the illumination optics; wherein the focal length can be varied by driving the illumination optics through the focal length control unit.

According to a further embodiment, the illumination optics can be designed such that a vergence of the reflected light beam path in the object plane and / or a position of the scanning range of the OCT beam can be varied.

The illumination optics can be configured such that a focal length of the illumination optics can be varied and / or that a distance of a light entry of the reflected light beam path and / or the OCT beam path into the illumination optics from a main plane of the illumination optics can be varied.

For example, an end section of a light guide can be connected to an actuator, so that a distance of a light exit surface of the end section from a main plane of the illumination optical system, measured along an optical axis of the illumination optical system, can be varied.

The convergence of the reflected light beam may be variable so that eyes with a refractive error of -20 D to +20 D can be illuminated so that a diameter of the illumination spot on the retina is less than 0.7 millimeters, or less than 0.3 millimeters , or less than 0.1 millimeter, or less than 50 microns, or less than 25 microns. The diameter of the illumination spot may be larger than 15 microns. Thus, for example, in cataract surgery, even a small diameter illumination spot may be created on the retina after the lens has been removed from the capsular bag of the eye.

The microscopy system may be designed so that the scanning region of the OCT beam path can be positioned in a front region or on the retina of the eye to be examined.

According to a further embodiment, the imaging optics is further configured to generate a second image in a second image plane of the imaging optics from the object region through a second observation beam path of the imaging optics; wherein the illumination optics is further configured to direct light of a further light source of the microscope system to the object plane; wherein in the incident-light operating mode the Illumination optics generates a further reflected light beam path for generating the second image; wherein an axis of the reflected light beam path having an axis of the first observation beam path in the object plane has an angle that is less than 6 degrees or less than 4 degrees or less than 2 degrees or less than 1 degree; and wherein an axis of the further reflected light beam path having an axis of the second observation beam path in the object plane has another angle that is less than 6 degrees or less than 4 degrees or less than 2 degrees or less than 1 degree.

Thereby, a microscopy system is obtained, which allows a stereoscopic examination of the eye.

An axis of the observation beam path and an axis of the further observation beam path can form a stereo angle in the object plane. The stereo angle may be, for example, between 5 degrees and 20 degrees or between 10 degrees and 16 degrees.

According to a further embodiment, the further reflected light beam path illuminates the object plane in parallel; or the further reflected light beam path has a divergence or convergence in the object plane that corresponds to a focal distance from the object plane that is greater than 2 cm, or greater than 5 cm, or greater than 10 cm, or greater than 15 cm.

According to a further embodiment, the further reflected light beam path in the object plane has a diameter that is greater than 1 millimeter, or greater than 2 millimeters or greater than 4 millimeters, or greater than 6 millimeters. The further reflected light beam path can be fixed in directions perpendicular to its axis by the illumination optics. In other words, the further reflected light beam path performs no raster movement.

According to a further embodiment, the OCT system has a further optical waveguide, which is designed to guide the light of the further light source to a light entrance of the further reflected light beam path.

According to a further embodiment, the microscopy system comprises a further OCT system, the OCT system having the further light source. The OCT system and the other OCT system may each have operating wavelengths that are different. For example, the first OCT system may have a working wavelength of 810 nanometers while the second OCT system has a working wavelength of 1310 nanometers. According to a further embodiment, the microscopy system has a further OCT operating mode, in which the illumination optics generates a further OCT beam path of the light of the further light source in order to scan a further scanning region of the further OCT system.

The focal distance may be measured along an axis of the further reflected light beam.

According to a further embodiment, the microscopy system is further configured such that at a narrowing of the further reflected light beam path, from which the further reflected light beam path diverges, the following applies:

D ₂ ^■ sin (o: ₂ ) <₂; wherein D _{2 is} a diameter of the further reflected light beam path at the constriction; and a _{2 is} an opening angle of the further reflected light beam path at the constriction; wherein M _{2 has} a value of 0.9 millimeters, or has a value of 50 microns, or has a value of 2 microns.

According to another embodiment, M _{2 has} a value of 0.5 millimeters, or a value of 0.1 millimeters, or a value of 30 microns, or a value of 20 microns, or a value of 10 microns, or a value of 5 microns, or a value of 3 microns.

According to another embodiment, the opening angle a _{2 is} less than 50 degrees, or less than 45 degrees, or less than 30 degrees, or less than 20 degrees, or less than 15 degrees, or less than 5 degrees, or less than 1 degree, or less than 0.5 degrees, or less than 0.1 degrees.

In another embodiment, the diameter D _{2 is} less than 1.5 millimeters, or less than 1 millimeter, or less than 0.5 millimeters, or less than 0.1 millimeters, or less than 50 microns, or less than 20 microns, or less than 10 microns, or less than 5 microns. The diameter D ₂ may depend on a working wavelength of the OCT system. The values for M ₂ , a ₂ and D ₂ may each be the same or different, to the corresponding values of M, a and D. The constriction can be a position along the

Be further axis of the incident light beam, from which the reflected light beam path diverges in the direction of the object plane. The opening angle may be an object-side opening angle. Brief description of the drawings

FIG. 1 schematically shows a microscopy system according to a first embodiment

exemplary;

FIGS. 2a and 2b

schematically show the reflected light beam path in the object plane, as it is generated by the microscopy system shown in Figure 1; schematically illustrates the generation of the red reflex by the reflected light beam path of the microscope system shown in FIG. 1; schematically shows an end portion of the optical waveguide of the microscope system shown in Figure 1; schematically shows the profile of the transmittance in the optical filter of the microscope system shown in Figure 1; schematically shows a microscopy system according to a second embodiment; schematically shows the switching from incident light illumination mode in the OCT illumination mode in the microscope system shown in Figure 5 according to the second embodiment; and shows a part of a microscopy system according to a third exemplary embodiment.

Detailed Description of Exemplary Embodiments

FIG. 1 schematically illustrates a microscopy system 100a according to a first exemplary embodiment. The microscopy system 100a has an imaging optics 50a which generates an observation beam path 20a with which an image of a region of an object plane OP-A in an image plane IP1-A is generated. In particular, the imaging beam path 20a has an objective lens 30a, a zoom system 32a, an image plane focusing optics 35a, 36a, and another image plane focusing optics 37a.

The microscopy system 100a further comprises an OCT system 60a, with which a scanning region can be scanned, which are located in the front region of the eye 1 or in the retina 6 of the eye 1 can. The light for the measurements of the OCT system 60a is generated by a light source 61a, which is for example a superluminescent diode.

The microscopy system 100a has two modes of operation: an OCT mode of operation in which the scan area is scanned to produce OCT data, and an epi-illumination mode of operation in which the image sensor 34a and / or the image sensor 38a form an image of an area of the Object level OP-A is detected by the imaging optics 50a. In both modes of operation, the light source 61a of the OCT system 60a is used. In the OCT operating mode, the light emitted by the light source 61a is supplied to an optical coupler 63a via an optical waveguide 68a. The light is coupled into a reference path and a measuring path via the optical coupler 63a. In the reference path, the light passes through an optical waveguide 69a, an optic 65a, and is reflected by a mirror 64a, which is designed to be movable so that a length of the reference path is adjustable. In the measurement path, the light is supplied via an optical waveguide 66a to a lighting optical system 70a. The illumination optical unit 70a generates an OCT beam path I Ia, which has a focus F in the scanning area. The scanning region can be, for example, in the front region of the eye 1 or in the retina 6. Light which is backscattered by the tissue structures of the eye passes through the illumination optics 70a and the optical waveguide 66a into the optical coupler 63a, is superimposed on the light reflected at the mirror 64a and fed via an optical waveguide 67a to a detector 62a. The detector 62a may, for example, comprise a photodiode which detects an interference between the measuring arm and the reference arm.

In the reflected-light operating mode, the light of the light source 61a is used to illuminate the object plane OP-A of the microscope system such that an image of a region of the object plane OP-A can be detected with the image sensor 34a and / or the image sensor 38a.

The illumination optics 70a is designed such that in reflected-light operating mode an incident-light beam path 10a of the light of the light source 61a can be generated. The reflected light beam path 10a illuminates the object plane OP-A in parallel or is configured so that a divergence or convergence of the reflected light beam path in the object plane OP-A corresponds to a distance of a focal point from the object plane OP-A which is greater than 2 cm.

In both operating modes, the light from the light source 61a is supplied to the illumination optics 70a via the light guide 66a. The reflected light beam path 10a and the OCT beam path 11a respectively pass through the objective lens 30a of the microscopy system. The reflected light beam path and the OCT beam path are directed onto the objective lens 31a via a beam splitter 31a. Therefore, the illumination optical system 70a has the objective lens 30a. Furthermore, the illumination optics has an optical system 13a which has a positive or a negative focal mode and which can have one or more lenses and / or cemented elements. Furthermore, a deflection unit 15a is arranged in the OCT beam path and in the reflected light beam path. The deflection unit 15a is designed such that the scanning region can be scanned through the OCT beam path by means of an X deflection and a Y deflection. The X-axis and the Y-axis in this case define a plane which is arranged parallel to the object plane OP-A of the imaging optics. The deflection unit may, for example, have a plurality of mirrors.

FIG. 2a schematically shows the reflected-light beam path 10a in the object plane OP-A along an axis OA-I of the incident-light beam path in the case of parallel illumination. In the case of parallel illumination, the reflected-light beam 10a forms plane or substantially even wavefronts in the object plane OP-A. In other words, the reflected light beam 10a has an opening angle of zero degrees or substantially zero degrees in the object plane OP-A. This illumination makes it possible to produce a red reflex on a right-justified, infinitely accommodated eye, which allows an observation of the anterior region of the eye with a sufficiently high contrast. The generation of the red reflex is shown schematically in FIG. Incident light 10, which consists at least approximately of flat wavefronts, is focused by the cornea 2 and the natural lens 7 onto a spot 5 on the retina 6. At this illumination spot 5, the incident light is scattered diffusely, so that the diffusely reflected light leaves the illumination spot 5 in the form of spherical (or approximately spherical) wavefronts 8. The spherical wavefronts 8 are converted by the natural lens 7 and the cornea 2 in outgoing light 9, which in turn consists approximately of flat wavefronts. The outgoing light 9 has an output direction opposite to the incident direction of the incident light 10. This is indicated by corresponding arrows in FIG. The red-light reflex can be used in a microscopic examination on the eye 1 to illuminate objects 23 in the front region of the eye 1 by the light reflected at the retina 8, 9 in transmitted light. The anterior region may include the cornea 2, the anterior chamber 11, the lens 7, and the posterior chamber 22. If, as shown in FIG. 1, the object plane OP-A of the microscope system 100a is arranged in the front region of the eye 1 and the illumination of the microscope is configured such that a red-light reflection is produced, the objects 23 appear in reddish transmitted light. Thus, it is possible, for example, that even small tissue remnants in the capsular bag can be observed during cataract surgery. By a refractive error of the eye 1, the illumination spot 5 can be increased in parallel illumination by the incident light 10. This can lead to deviations of the wavefronts of the outgoing light 9 of which reduce a contrast in a microscopic image with the red reflex. The illumination optics can be designed so that an incident light beam can be generated which deviates from the parallel illumination. As a result, even in the case of defective eyes, a lighting spot 5 on the retina be generated, which has a sufficiently small diameter. As a result, a high-contrast image of the front region of the eye 1 can be obtained.

This adaptation of the reflected light beam path is shown schematically in FIG. 2b.

The reflected light beam path 10a has an opening angle Θ in the object plane OP-A. The opening angle can be defined as the largest angle which the light beams of the reflected-light beam path 10a form in the object plane OP-A. The opening angle may be a far-field opening angle. A vertex of the opening angle Θ is either a convergence point CP having a distance d from the object plane, or a divergence point, depending on whether the reflected light beam path 10a bundles in front of or behind the object plane OP-A. The convergence point or divergence point can be a virtual focal point. The distance d is measured along the axis OA-I of the reflected light beam 10a. The illumination optics are configured so that the distance of the convergence point CP or the divergence point is greater than 2 cm.

Thereby, in the reflected-light operating mode, illumination is obtained with which even in a refractive eye, or in an eye from which the natural lens has been removed, an illumination spot 5 (shown in Fig. 3) can be formed on the retina 6, one has sufficiently small diameter.

The imaging optics of the microscopy system 100a shown in FIG. 1 furthermore have a beam splitter 43a with which the observation beam path 20a is divided into two branches. The portion of the light transmitted through the beam splitter 43a is imaged onto the first image plane IP1-A via the image plane focusing optics 35a, 36a. The part of the light reflected by the beam splitter is imaged via another image plane focusing optics 37a onto a further image plane IP2-A, which is also optically conjugate to the object plane OP-A.

In the first image plane IP1-A, the first image sensor 34a is arranged in a camera 39a; and in the further image plane IP2-A, the further image sensor 38a is arranged in a further camera 42a. The image sensors 34a, 38a may be CCD image sensors, for example.

In the imaging beam path 20a between the object plane OP-A on the one hand and the image planes IP1-A, IP2-A, a color filter 40a is arranged. A spectral transmittance τ (λ) of the color filter 40a is shown in FIG. 4b. At a cut-off wavelength λ _c , the transmittance is 50% of a maximum transmittance that occurs at a wavelength λ _max in a passband of the filter 40a. The OCT light source 61a emits light having wavelengths longer than the cut-off wavelength λ _c . In particular, an operating wavelength of the OCT system 60a can be above the cutoff wavelength X _c. Alternatively or in addition to the image sensors 37a, 38a shown in FIG. 1, the imaging optics 50a may have eyepieces (not shown in FIG. 1). The eyepieces can be designed so that the image in the image plane IP1-A and / or in the image plane IP2-A can be viewed by a viewer.

The imaging optics 50a further comprises a zoom system 32a, which is arranged in the imaging beam path between the beam splitter 3a and the beam splitter 43a.

A first component 36a of the image plane focusing optics is formed such that the intermediate plane IMP-A is an optically conjugate plane to the retinal plane RP-A. For example, bundles of rays emanating from the object plane OP-A as a parallel beam along an axis OA-A of the observation beam path can be focused in an intermediate plane IMP-A in one point. In other words, the retinal plane RP-A is imaged by the natural lens 7, the cornea 2 and the imaging optics 50a into the intermediate plane IMP-A. The imaging optics 50a may have a variable focal length that is designed to be effective even with a refractive eye; or in an eye from which the natural lens has been removed, the intermediate plane IMP-A is further optically conjugate to the retinal plane RP-A.

In the intermediate plane IMP-A, a contrast element 33a is arranged. The contrast element is arranged to (a) absorb light more strongly in a central region of a cross section of the observation beam path within the intermediate plane IMP-A than outside the central region; and / or that (b) light in the central region within the intermediate plane IMP-A undergoes a phase shift which is different from a phase shift outside the central region within the intermediate plane IMP-A.

This makes it possible, in the incident-light operating mode, to obtain a phase-contrast microscopic image and / or a dark-field image of objects in the object plane OP-A. By using the OCT light source 61a as reflected-light illumination, as described with reference to FIGS. 2a and 2b, a particularly high-contrast phase contrast or dark field image can be obtained.

As further shown in FIG. 1, an end section 14a of the optical waveguide 66a, which faces the illumination optical system, has a light exit surface 12a.

Figure 4a is a schematic representation of the end portion 14a of the light guide 66a. From a light exit surface 12a of the end portion 14a, the light exits the light guide and enters the illumination optics. The light exit surface 12a is an exposed surface of a core 80a of the end portion 14a. The core is surrounded by a jacket 82a. For the reflected light beam path 10a, the light exit surface 12a is a constriction, from which the Reflected light beam 10a diverges. A cross section of the exit surface forms a diameter D of the reflected light beam path 10a at the constriction. The cross section D corresponds to a diameter of the core 80a.

As shown in FIG. 4 a, the light emerges from the light exit surface 12 a on the object side with an opening angle a and forms a light entrance of the reflected light beam path 10 a. The reflected light beam path 10a extends along an axis OA-I to the object plane. The microscopy system is designed so that for the constriction of the reflected light beam path 10a: i o D - sin (a) <; where D is the diameter of the incident light beam 10a at the throat; and a is the object side opening angle of the reflected light beam path 10a at the constriction; wherein M has a value of 0.9 millimeters, or has a value of 50 microns, or 15 has a value of 2 microns.

The opening angle a may be twice an acceptance angle of the end portion 14a of the optical waveguide. However, it is also conceivable that an aperture 81a in the reflected light beam path 10a limits the aperture angle a of the reflected light beam path 10a.

20

By using an optical waveguide, a small diameter of the exit surface 12a and a small opening angle of the reflected light beam path is achieved, whereby a small illumination spot 5a on the retina 6 of the eye 1 can be generated with sufficiently high power of the illumination light. The optical waveguide 66a may be a multimode optical fiber or a single mode optical waveguide for a working wavelength of the OCT system.

It is further conceivable that the OCT system 60a (shown in FIG. 1) is configured to direct light of a laser to the optical system 13a without passing the light of the laser 0 through an optical fiber. In this case, the constriction can be, for example, a focal point of the laser beam, or be arranged on a light exit surface of the laser beam from the laser.

FIG. 5 shows a schematic representation of a stereo microscope system 100b, which-in a manner analogous to that of the microscope system 100a shown in FIG. 1 -is designed to produce microscopic images of the eye 1. The stereo microscopy system 100b has components that are analogous to components of the microscopy system 100a. Therefore, these components are provided with similar reference numerals, however, have the sign b for a first illumination or imaging beam path and the sign b 'for a 0 second illumination or imaging beam path. The stereo microscope system 100b has an imaging optical unit 50b, which has a first axis OA-B of a first observation beam path 20b, and a second axis OA-B 'of a second observation beam path 20b'. In the object plane OP-B, the axes OA-B and OA-B 'form a stereo angle Θ.

The stereo microscope system 100b has an objective lens 30b, which is penetrated by both observation beam paths 20b, 20b '. Furthermore, the stereo microscopy system 100b has an illumination optics 70b which is designed to direct two reflected light beam paths 10b, 10b 'onto the object plane OP-B. The illumination optics 70b is configured such that an axis of the first reflected light beam path 10b forms an angle of less than 6 degrees with the axis of the first observation beam path 20b. Further, the illumination optics is configured such that an axis of the reflected light beam path 10b 'forms an angle of less than 6 degrees with an axis of the second observation beam path 20b'.

The reflected light beam paths 10b, 10b 'in the object plane OP-B each form a parallel illumination. Alternatively, the first and / or the second reflected light beam path 20b, 20b 'in the object plane OP-B has a convergence or divergence which corresponds to a focal distance from the object plane, measured along the axis of the respective reflected light beam path, which is greater than 2 cm, or greater than 5 cm, or greater than 10 cm; or larger than 15 cm.

The beams of the reflected light beam paths 10b, 10b 'penetrate the cornea 2 and the natural lens 7 and are focused on the respective illumination spots 5b and 5b' on the retina. At each of the illumination spots 5b and 5b ', the illumination light is reflected diffusely and emanates from each of the illumination spots 5b and 5b' as an approximately spherical wave function.

Furthermore, the microscope system 100b has a first and a second contrast element 33b, 33b 'for generating phase-contrast or dark-field images.

The stereo microscope system 100b can be designed so that the reflected light beam paths 10b, 10b 'are activated alternately. In this case, light from the first imaging beam path 20b and the second imaging beam path 20b 'may be directed to a common image sensor (not illustrated) after passing through common imaging optics (not illustrated). The common image sensor then alternately generates images by light beams of the first imaging beam path 20b and by light beams of the second imaging beam path 20b '. The illumination optics 70b comprises an optical system 13b, which is penetrated by both reflected light beam paths 10b, 10b 'and which has a focal length. Alternatively or additionally, it is conceivable that each of the reflected light beam paths 10b, 10b ^! enforced a separate optical system.

The microscopy system 100b has a first OCT system 60b. The illumination optics 70b generates the first reflected light beam path 10b from light of the light source of the first OCT system 60b. The microscopy system 100b may further include a second OCT system 60b ', wherein the illumination optics 70b generates the second reflected light beam 10b' from light from the light source of the second OCT system 60b '. Alternatively, it is conceivable that the second OCT system 60b 'is replaced by a light source. The first OCT system 60b and the second OCT system 60b 'may have different operating wavelengths. For example, the first OCT system 60b may have a working wavelength of 810 nanometers while the second OCT system 60b 'has a working wavelength of 1310 nanometers. For OCT examinations in the retina, a wavelength of 810 nanometers may be advantageous while for the anterior region of the eye a wavelength of 1310 nanometers may be beneficial.

The axis OA-I of the first reflected light beam path 10b and the axis ΟΑ-Γ of the second reflected light beam path 10b 'each extend at a radial distance relative to an optical axis OA-C of the illumination optical system 70b.

FIG. 6 illustrates a switching operation of the illumination optics 70b of the microscopy system 100b shown in FIG. 5 from the reflected-light operating mode to the OCT operating mode. The microscopy system 100b is configured such that an end portion 14b of an optical waveguide, which is arranged in the optical path of the light between the OCT system 60b and the illumination optics 70b, is movable. For example, an actuator (not shown in FIG. 6) may be arranged at the end portion 14b such that the light exit surface 12b of the light guide 66b is movable in one direction so that a radial distance of the light exit surface 12b from the optical axis OA-C of the illumination optics 70b is changeable. As shown in FIG. 6, the end portion 14b of the optical waveguide 66b is convertible from a position A to a position B when switching from the reflected-light operating mode to the OCT operating mode, whereby the axis of the OCT beam path 10b on the optical axis OA-C of the illumination system can be aligned. In other words, the OCT beam 10b extends substantially along the optical axis OA-C of the illumination system when the deflection unit 15b does not deflect the OCT beam to perform a scanning movement. In the region of the light entry and in the objective lens 30b, the reflected light beam paths 10b, 10b 'each extend at a distance relative to the optical axis OA-C of the illumination system 70b. With an OCT beam 10b aligned along the optical axis OA-C of the illumination optics 70b, improved imaging of the tissue structures with OCT can be achieved. In particular, this is advantageous if the retina 6 of the eye 1 is imaged. The microscope system 100b is further designed such that when switching from the incident-light operating mode to the OCT operating mode, the focal length of the illumination optics 70b is also variable. As a result, the scanning region of the OCT beam I Ib can be positioned, for example, in the front region of the eye 1. The change in the focal length can be effected, for example, by changing the focal length of the optical system 13b of the illumination optical unit 70b. In FIG. 6, this is indicated schematically by the double arrow 90.

FIG. 7 illustrates part of a stereoscopic microscopy system according to a third exemplary embodiment. The microscopy system shown in FIG. 7 has components which are analogous to components of the microscopy system 100b shown in FIG. Therefore, these components are provided with similar reference numerals, however, have the accompanying c. Also in the microscopy system shown in FIG. 7, the further OCT system 60c 'can be replaced by a further light source. The microscopy system shown in FIG. 7 has an optical switch 82c which is arranged in the optical path between the OCT system 60c and the illumination optics 70c and in the optical path between the further OCT system 60c 'and the illumination optics 70c. The optical switch 82c may be formed so that a first optical connection between the OCT system 60c and the light exit surface 12c ", a second optical connection between the OCT system 60c and the light exit surface 12c", a third optical connection between the other. OCT system 60c 'and the light exit surface 12c "and / or a fourth optical connection between the further OCT system 60c' and the light exit surface 12c 'is unlockable and / or lockable .A first optical fiber 93c is an optical connection between the optical switch 82c and the first light exit surface 12c. A second light guide 93c "is an optical connection between the optical switch 82c and the light exit surface 12c". A third light guide 93c 'is an optical connection between the optical switch 82c and the light exit surface 12c'.

The second light guide 93c "is arranged so that an axis of the second light guide is aligned with the light exit surface 12c" on the optical axis OA-C of the illumination optical system 70c. It is conceivable that an optical coupler is used instead of the optical switch 82c. The optical switch 82c may be configured to simultaneously guide light to each of the light exit surfaces 12c, 12c ', 12c. "Thereby, the microscope system is operable simultaneously in the reflected light operating mode and in the OCT operating mode, for example, thereby simultaneously providing OCT data acquisition This is advantageous for interventions on the anterior chamber, in particular for cataract surgery.

Alternatively or additionally, the optical switch 82c may be configured so that the light which is fed into the second optical fiber 93c "is selectively generated either from the light source of the OCT system 60c or from the further light source of the further OCT system 60c '. Thereby, the optical switch 82c can switch between a first OCT mode of operation for measurement with the OCT system 60c and a second OCT mode of operation for measurement with the further OCT system 60c 'However, it is also conceivable that with both OCT systems For this purpose, the optical switch 82c can be designed such that simultaneously the second optical connection between the OCT system 60c and the light exit 12c "and the third optical connection between the further OCT system 60c 'and the light exit The illumination system 70c shown in Figure 7 further comprises focusing optics 83c. The OCT-Stra hl 1 1c passes through the focusing optics 83c and the reflected light beam paths 10c, 10c 'bypass the focusing optics. This makes it possible, as an alternative or in addition to a focal length adjustment by moving optical components of the illumination optics (indicated by the double arrow 90c) to obtain a changed focal length of the illumination optics passing through the OCT beam in comparison to the reflected light beam path. Alternatively, it is also conceivable that the focusing optics 83c is designed so that the reflected light beam paths 10c, 10c 'pass through the focusing optics and the OCT beam path 11c bypasses the focusing optics. By the focusing optics 83c, a microscopy system is obtained, which is quickly switchable between the OCT operating mode and the incident light operating mode. Furthermore, the microscope system can thereby be operable simultaneously in the incident-light operating mode and in the OCT operating mode.

The microscopy system shown in FIG. 7 has a front-end OCT operating mode and a retinal OCT operating mode, both of which represent an OCT operating mode.

The microscope system has a reducing lens 91c and an ophthalmoscopic magnifier 92c, which can be introduced into the OCT beam path 11c. Instead of the ophthalmoscope magnifier 92c, a contact lens may be used. The reduction lens 91c and the ophthalmoscope magnifier 92c displace the scanning region of the OCT beam path into the retina 6. Thereby can In OCT operating mode, OCT data are obtained from the retina by a fundus scan. The microscope system is designed such that in the retinal OCT operating mode, the reducing lens 91c and the ophthalmoscopic magnifier 92c are arranged in the OCT beam path between the objective lens 30c and the object plane OP-B in the OCT beam path 11c, so that the light entry of the OCT Beam path over an intermediate level IP on the retina 6 of the eye 1 is mapped. In the front-end OCT operating mode, the reducing lens 91c and the ophthalmoscopic magnifier 92c are disposed outside the OCT optical path 1 lc.

The microscopy system is further configured such that when switching between the front-end OCT operating mode and the retinal OCT operating mode, the length of the reference path is changed. For example, this can be achieved by changing a position of the mirror in the reference arm. Furthermore, the microscope system can be designed such that when switching between the front-end OCT operating mode and the retina OCT operating mode, an optical element is pivoted into the reference arm. The optical element may be configured to compensate for a difference in a dispersion in the measuring arm that occurs between the front-end OCT operating mode and the retinal OCT operating mode.

Alternatively or additionally, the microscopy system may be configured such that the front-end OCT operating mode corresponds to the first operating mode in which OCT measurements can be carried out with the OCT system 60c and the retinal OCT operating mode corresponds to the second operating mode in which the further OCT system 60c 'OCT measurements are feasible. The operating wavelength of the OCT system 60c may be optimized for an OCT scan of a frontal region of the eye. The operating wavelength of the further OCT system 60c 'may be optimized for an OCT scan of the retina.

Claims

claims

Microscopy system (100a) for eye examination, comprising: imaging optics (50a) for generating a first image in a first image plane (IP1-A) of the imaging optic (50a) from a region of an object plane (OP-A) of the imaging optic (50a) through a first observation beam path (20a) of the imaging optics (50a); an OCT system (60a) for acquiring OCT data, the OCT system (60a) having a light source (61a) and an interferometer; and illumination optics (70a) for directing light from the light source (61a) to the object plane (OP-A); wherein the microscopy system (100a) has an OCT mode of operation in which the illumination optics (70a) generates an OCT (I Ia) of the light of the light source (61a) to scan a scanning area of the O CT beam path (I Ia); and wherein the microscopy system (100a) further comprises an incident light operating mode in which the illumination optics (70a) generates an incident light path (10a) of the light of the light source (61a) to produce the first image; wherein the reflected light beam path (10a) illuminates the object plane (OP-A) in parallel; or wherein the reflected light beam path (10a) in the object plane (OP-A) has a divergence or convergence corresponding to a focal distance (d) from the object plane (OP-A) greater than 2 cm.

Microscopy system (100a) according to claim 1, wherein the microscope system (100a) is formed such that at a constriction of the reflected light beam path (10a) from which the reflected light beam path (10a) diverges, the following applies:

D ^■ sin (a) <M; wherein D is a diameter of the reflected light beam path (10a) at the constriction; and a is a objektsei term opening angle of the reflected light beam path (10 a) at the constriction; where M has a value of 0.9 millimeters. Microscopy system according to claim 2, wherein M has a value of 0.1 millimeter.

Microscopy system according to claim 2, wherein M has a value of 50 microns. Microscopy system according to claim 2, wherein M has a value of 10 microns. Microscopy system according to claim 2, wherein M has a value of 5 microns. Microscopy system (100a) for eye examination, comprising: an imaging optics (50a) for generating a first image in a first image plane (IP-A) of the imaging optics (50a) from a region of an object plane (OP-A) of the imaging optics (50a) through a first observation beam path (20a) of the imaging optics (50a); an OCT system (60a) for acquiring OCT data, the OCT system (60a) having a light source (61a) and an interferometer; and illumination optics (70a) for directing light from the light source (61a) to the object plane (OP-A); wherein the microscopy system (100a) has an OCT mode of operation in which the illumination optics (70a) generates an OCT (I Ia) of the light to scan a scan area of the OCT beam (Ha), and wherein the microscopy system (100a) further an incident light operating mode in which the illumination optics (70a) generates an incident light path (10a) of the light to produce the first image; wherein at a constriction of the reflected light beam path (10a) from which the reflected light beam path (10a) diverges, the following applies:

D ^■ sm ^' (a) <M; wherein D is a diameter of the reflected light beam path (10a) at the constriction; and a is an object-side opening angle of the reflected light beam path (10a) at the constriction; where M has a value of 0.9 millimeters.

Microscopy system according to claim 7, wherein M has a value of 0.1 millimeters. Microscopy system according to claim 7, wherein M has a value of 50 microns.

10. Microscopy system according to claim 7, wherein M has a value of 10 microns.

1 1. A microscopy system according to claim 7, wherein M has a value of 5 microns.

12. Microscopy system (100a) according to one of the preceding claims, wherein the microscopy system (100a) has an image sensor (34a) which is arranged in the first image plane (IP-A) for a light detection in incident light operating mode, wherein the microscopy system (100a ) is configured so that the light detection is suppressed for wavelengths shorter than a cut-off wavelength (X _c ); wherein the light of the light source (61a) has wavelengths longer than the cut-off wavelength (λ _c ); and wherein the cut-off wavelength (L _c ) is greater than 700 nanometers.

13. Microscopy system (100a) for eye examination, comprising: imaging optics (50a) for generating a first image in a first image plane (IP-A) of the imaging optics (50a) from an area of an object plane (OP-A) of the imaging optics (50a) by a first observation beam path (20a) of the imaging optics (50a); a first image sensor (34a) disposed in the first image plane (IP-A); an OCT system (60a) for acquiring OCT data, the OCT system (60a) having a light source (61a) and an interferometer; illumination optics (70a) for directing light from the light source (61a) to the object plane (OP-A); wherein the microscopy system (100a) has an OCT operating mode in which the illumination optics (70a) generates an OCT beam path (II a) of the light of the light source (61a) to scan a scanning range of the OCT beam path (I Ia), and wherein the microscopy system (100a) further comprises an incident light operating mode in which the illumination optics (70a) generates an incident light path (10a) of the light from the light source (61a) to produce the first image; wherein the microscopy system (100a) comprises an image sensor (34a) disposed in the first image plane (IP-A) for light detection in the incident light operating mode, wherein the microscopy system (100a) is configured to suppress the light detection for wavelengths shorter than a cut-off wavelength; wherein the light of the light source (61a) has wavelengths longer than the cut-off wavelength (L _c ); and wherein the cutoff wavelength (λ _c ) is greater than 700 nanometers.

The microscopy system (100b) of any one of the preceding claims, further comprising an actuator attached to a component of the illumination optics (70b) and / or to a light guide (66b), the light guide guiding the light to the illumination optics (70b); and a control unit connected to the actuator; wherein a control of the actuator by the control unit, a radial distance of an axis of the OCT beam path (Hb) and / or a radial distance of an axis of the reflected light beam path (10b) relative to an optical axis of the illumination optical system (OA-C) is adjustable.

15. Microscopy system (100c) according to one of the preceding claims; wherein the microscopy system (100c) further comprises: a light guide (93c ") which guides the light of the light source to a light entrance of the OCT beam path (1 lc) into the illumination optics (70c); and another light guide (93c) comprising the Light of the light source to a light entrance of the reflected light beam path (10c) in the illumination optical system (70c) leads.

16. microscopy system (100c) according to any one of the preceding claims, wherein the illumination optics (70c) further comprises a focusing optics (83 c), wherein the OCT beam path (1 1c) passes through the focusing optics (83c) and the reflected light beam path (10c) the focusing optics (83c) bypasses; or wherein the OCT beam path (11c) bypasses the focusing optics (83c) and the reflected light beam path (10c) passes through the focusing optics (83c).

17. microscopy system (100c) according to any one of the preceding claims, wherein in the object plane (OP-A) an axis of the reflected light beam path (10a) and / or an axis of the OCT beam path (I Ia) with an axis (OA-A) of the first observation beam path (20a) has an angle which is less than 6 degrees; or less than 4 degrees.

18. Microscopy system (100a) according to one of the preceding claims, wherein the imaging optics (50a) has a first contrast element (33a) which is arranged in a first intermediate plane (IMP-A) of the first observation beam path (20a), wherein the first intermediate plane ( IMP-A) between the object plane (OP-A) and the first

Image plane (IP-A) is arranged; wherein the first contrast element (33 a) is formed so that light which impinges on a central region of a cross section of the first observation beam path (20a) within the first intermediate plane (IMP-A): a) is absorbed more strongly than in the first intermediate plane ( IMP-A) outside the central area; and / or b) experiences a phase shift which is different from a phase shift in the first intermediate plane (IMP-A) outside the central region.

19. microscopy system (100a) according to one of the preceding claims, wherein the illumination optics (70a) further comprises a deflection unit (15a) which is arranged in the OCT beam path (I Ia).

The microscopy system (100a) of any one of the preceding claims, wherein the illumination optics (70a) has a variable focal length; the microscopy system (100a) further comprising a focal length control unit connected to the illumination optics (70a); wherein by driving the illumination optical system (70a) through the focal length control unit, the focal length is variable. 21. Microscopy system (100b) according to one of the preceding claims, wherein the imaging optics (50b) is further configured to generate a second image in a second image plane (ΙΜΡ-Β ') of the imaging optic (50b) from the object region through a second observation beam path (20b'). ) the imaging optics (50b); wherein the illumination optics (70b) is further configured to direct light of a further light source of the microscope system to the object plane (OP-B); wherein in the incident light operating mode, the illumination optics (70b) generates a further reflected light beam path (10b ¹ ) for generating the second image; wherein in the object plane (OP-B) an axis (OA-I) of the reflected light beam path (10b) having an axis (OA-B) of the first observation beam path (20b) has an angle which is less than 6 degrees or less than 4 Degree; and wherein in the object plane (OP-B) an axis (ΟΑ-Γ) of the further reflected light beam path (10b ') having an axis (ΟΑ-Β') of the second observation beam path (20b ') has a further angle which is less than 6 Degrees or less than 4 degrees.

The microscopy system (100b) of claim 21, wherein the further reflected light beam path (10b ') illuminates the object plane (OP-B) in parallel; or wherein the further reflected light beam path (10b ') in the object plane (OP-B) has a divergence or convergence that corresponds to a focal distance (d) from the object plane (OP-B) that is greater than 2 cm.

23. Microscopy system according to claim 21 or 22, wherein the microscopy system (100b) is further configured such that at a constriction of the further Auflichtstrahlengangs

(10b ') from which the further reflected light beam path (10b') diverges, the following applies:

Z ₂ - sin (a ₂ ) <₂; wherein D _{2 is} a diameter of the further reflected light beam path (10b ') at the constriction; and a _{2 is} an object-side aperture angle of the further reflected light beam path (10b ¹ ) at the constriction; wherein M _{2 has} a value of 0.9 millimeters, or has a value of 0.1 millimeters, or has a value of 50 microns, or has a value of 10 microns, or has a value of 5 microns.