Patent Issued for Integrated Device For Ophthalmology (USPTO 10,582,851)

2020 MAR 25 (NewsRx) -- By a News Reporter-Staff News Editor at Insurance Daily News -- Wavelight GmbH (Erlangen, Germany) has been issued patent number 10,582,851, according to news reporting originating out of Alexandria, Virginia, by NewsRx editors.

The patent’s inventors are Donitzky, Christof (Eckental, DE); Wuellner, Christian (Brauningshof, DE).

This patent was filed on October 5, 2017 and was published online on March 23, 2020.

From the background information supplied by the inventors, news correspondents obtained the following quote: “Devices for ophthalmic diagnostics have been designed for very specific diagnostic applications. As an example, the ‘WaveLight.RTM. Topolyzer.TM. Vario.TM.’ and the ‘WaveLight.RTM. Oculyzer.TM.II’, each distributed by the applicant, provide topography measurements and Scheimpflug measurements, respectively. Furthermore, some of present-day devices for ophthalmic diagnostics house two different measuring technologies, which can only be applied one after another. The ‘Visionix L80 Wave+’ by Luneau/Visionix is an exemplary device for the latter. Provision and deployment of multiple devices for ophthalmology is disadvantageous because of high floor space requirements and multiple costs for both investment and maintenance, which can even impede an application of ophthalmic devices in medical practises or clinics. Also, cooperation of patients has been observed to cease when the patients undergo multiple measurements using different devices. It would be a significant advance for patients and economically oriented enterprises, including medical practises, clinics and health insurance funds, if it was possible to complete an ophthalmic procedure in shorter time.”

Supplementing the background information on this patent, NewsRx reporters also obtained the inventors’ summary information for this patent: “Accordingly, it is an object of the present invention to provide a device for ophthalmology that completes an ophthalmic procedure more rapidly with reduced space requirement.

“The object is solved by a device for ophthalmic radiation according to claim 1. The device comprises a radiation interface, an optical branch coupler and a plurality of ophthalmic units. The radiation interface is adapted to at least one of output and capture radiation on an optical path. The optical path is directable towards an eye. The optical branch coupler is adapted to couple output radiation from a plurality of optical branches into the optical path and to couple captured radiation from the optical path into the optical branches. The captured radiation is spectrally split into the optical branches. A different spectral range is coupled into each of the optical branches. Each of the ophthalmic units is arranged to couple to one, two or more of the optical branches.

“The radiation interface may have a radiation aperture. The radiation aperture may be realized by an opening in a housing of the device and may include at least one of a translucent window and an entrance lens. The radiation aperture may be adapted to output and/or capture the radiation on the optical path. The coupling of different spectral ranges into the optical branches may relate to the captured radiation from the optical path.

“Each of the ophthalmic units can operate in one or more of the different spectral ranges. The operation may include at least one of providing radiation and processing radiation. Each of the ophthalmic units may operate in a spectral range in correspondence to the one or more optical branches the respective ophthalmic units is arranged to couple to. Due to the spectral splitting, the device can provide multiple ophthalmic technologies using one and the same optical path. The spectral splitting may be in accordance with the different spectral ranges. The operation of one or all of the ophthalmic units may include measurements, which may include optical measurements. Some or all measurements may be performed on the optical path, which may define an optical measurement axis. Some or all ophthalmic units may perform their measurements on the optical path and may provide different ophthalmic technologies. The ophthalmic units may be operated independently.

“Advantageously in certain embodiments, many steps of one or more ophthalmic procedures can be completed in a shorter time. Using the same optical path, a more compact design of the device is achievable. Furthermore, the device can provide to a patient a uniform interface for a plurality of different ophthalmic technologies. A single uniform interface may be achieved by virtue of the radiation interface. Usage of several devices can be avoided. The device can complete ophthalmic procedures more rapidly. More patients can receive the latest ophthalmic technology faster and at lower costs.

“In particular, the device may be a device for optical ophthalmic or ophthalmologic analysis, diagnostics, and/or treatment. The analysis, diagnostics, or treatment may be contactless. The optical path may be the sole optical path of the device directable towards the eye. The coupling of the output radiation from the plurality of optical branches into the optical path may be a composition of the output radiation. The coupling of the captured radiation from the optical path into the optical branches may be a decomposition of the captured radiation. Throughout, the terms ‘light’ or ‘optical’, or the prefix ‘photo-’ can refer to electromagnetic radiation, or a component processing the same, in at least one of the infrared spectrum, the visual spectrum and the ultraviolet spectrum. Each of the spectral ranges in which a respective one of the ophthalmic units operates may be useful for a particular measurement. The operation of an ophthalmic unit can include at least one of analysis of captured radiation and emission of output radiation.

“The different spectral ranges may have at least one of different wavelengths (or frequencies) of electromagnetic radiation, different spectral maxima, different spectral centers, non-overlapping spectral ranges, separate spectral ranges, and disjoined spectral ranges. Based on the spectral splitting into the different spectral ranges, at least those ophthalmic units that are operable at the different spectral ranges may be independently designed. The ophthalmic units may be specified to operate within a predefined spectral range and may operate exclusively in that predefined spectral range. The predefined spectral range may be a subset of the different spectral ranges. As an advantage, the development of the device or a further development of the ophthalmic units may be distributed.

“Alternatively or in addition, the ophthalmic units or their operation may be interdependent. By example, a first ophthalmic unit can comprise an excitation light source adapted to emit excitation light in a first spectral range into a first optical branch. The captured radiation may comprise in a second spectral range fluorescent light. The fluorescent light may be induced, e.g., due to a fluorescent dye applied to the eye, by the excitation light. A second ophthalmic unit may be adapted to detect the fluorescent light. The second ophthalmic unit may be coupled to a second optical branch corresponding to the second spectral range. Alternatively, the second ophthalmic unit may also be coupled to the first optical branch. The first optical branch may carry radiation in both the first spectral range and the second spectral range.

“The optical coupler may include one or more beam splitters. Each of the one or more beam splitters may have a different spectral transmittance and/or a different spectral reflectance. Generally, the splitting may be based on interference in a coating, a layer, or a thin film. Each of the one or more beam splitters may comprise one or more of a pair of triangular glass prisms glued to each other, a partially transmissive mirror, a plate of glass with a thin coating providing partial reflection, a dichroic mirror, a substrate with a thin dielectric layer, a series of such layers, a series of an alternating arrangement of a metallic layer and a dielectric layer, and a dichroic prism. The triangular glass prisms may include isosceles and right-angled triangular glass prisms. The triangular glass prisms may be pairwise glued and may be glued to each other at the base surface.

“The optical coupler may include a dichroic prism. The dichroic prism may be multibranched (also referred to as a ‘multichannel dichroic prism’). Generally, the spectral splitting can be based on dichroism, particularly by means of interference and/or birefringence. The multibranched dichroic prism may comprise two or more glass prisms that have optical interfaces that include optical coatings adapted to selectively transmit or reflect radiation depending on the wavelength of the radiation, e.g., by means of interference, as mentioned above. Alternatively or in addition, the multibranched dichroic prism may comprise one or more of a dichroic crystal as a monocrystal and a birefringent crystal as a monocrystal. The multibranched dichroic prism may comprise one or more prisms made of a dichroic crystal or a birefringent crystal. A prism including at least one of a dichroic crystal and a birefringent crystal is collective referred to as ‘crystal prism’. The crystal or the crystal prism may have an index of refraction depending on at least one of the wavelength of the radiation and the polarization of the radiation. The dichroic splitting of the radiation can be much more efficient as compared to subtractive filters. Thus, an intensity of the output radiation applied to the eye, e.g. for illumination, can be reduced. Alternatively or in addition, the crystal or the crystal prism may have an absorptance depending on at least one of the wavelength of the radiation and the polarization of the radiation.

“The optical interfaces of the prisms, e.g., the glass prisms and/or the dichroic crystal prisms, may be arranged in direct contact and/or glued together. This allows for an even more compact design of the optical branch coupler, and thus of the device. Furthermore, the device is more robust. The device may be more shockproof due to the defined relative arrangement of optical components. The arrangement might be advantageous, e.g., when the device is a mobile device or a table-top device.

“The ophthalmic units may be operated simultaneously. The operation of any of the ophthalmic units may include at least one of analysis of the captured radiation and emission of the output radiation. As a result, several steps of the procedure may be performed in parallel. Thus, the time required for ophthalmic diagnostics and/or ophthalmic treatment can be reduced.

“A total number of the optical branches in the device may be two, three, four or five. The number of optical branches can correspond to the number of ophthalmic units coupled to one of the optical branches. This allows for including a plurality of ophthalmic units and corresponding ophthalmic technologies without increasing the size and complexity of the optical path or the radiation interface as the output of the device. Also, output optics may be shared by some or all ophthalmic units. The output optics may be arranged in the optical path.

“Moreover, two or more of the ophthalmic units may be arranged to couple to one of the optical branches. Thus, optical elements may be shared. For example, those optical elements that are used for two or more ophthalmic units may be shared. As a result, the two or more ophthalmic units can be reduced in size for a still more compact design of the device.

“The optical branch coupler may be arranged on the optical path. The optical branches may have a star-shaped arrangement with respect to the optical branch coupler. Similarly, the corresponding ophthalmic units coupled to the optical branches may have a star-shaped arrangement. The optical lengths of the optical branches may be adjustable or fixed. The optical lengths of the optical branches may be equalized or balanced. The optical branch coupler may be arranged, e.g., centered, in between the ophthalmic units. The ophthalmic units can be distributed in two dimensions or three dimensions with respect to the optical branch coupler. In the case of three optical branches, the optical path and the three optical branches may be arranged in a tetrapod structure. In the tetrapod structure, the optical path and the three optical branches, or their linear extensions, may enclose a tetrahedral angle. In the case of three ophthalmic units, the ophthalmic units may be arranged at three of the four tetrahedron vertices. The optical branch coupler may be located at the center of the tetrahedron.

“The radiation interface may be any at least partially transparent surface or an opening. The radiation interface can include output optics, particularly an objective. In certain embodiments, optical elements used, e.g., for directing the optical path towards the eye, by two or more of the plurality of ophthalmic units may be arranged as one interface towards the eye on the optical path. This allows the number of optical elements and the size of the device to be reduced.

“One or more of the ophthalmic units may be adapted to insert output radiation into its optical branch for ophthalmic treatment. The inserted output radiation can be laser light for ablation or ultraviolet light for cross-linking. The cross-linking (also referred to as ‘curing’ or ‘hardening’) may include a photooxidative cross-linking. UV-A light may be used for the cross-linking in conjunction with riboflavin, organic molecules in the class of diazirines, or any other suitable crosslinker. Alternatively or in addition, the device may perform a refractive surgery of the eye or a treatment of keratoconus. The output radiation may be in the UV, visible, or IR spectrum. The output radiation may be generated by an ultrashort pulse laser, such as a femtosecond laser or a picosecond laser or an attosecond laser. Advantageously, a result of the surgery or treatment can be observed or quantified in real time by one or more of the other ophthalmic units.

“One of the ophthalmic units may comprise a fixation unit adapted to at least one of detect a position of the eye, detect a movement of the eye, provide a fixation target, and/or provide an accommodation target on which the patient may focus. The eye may be detected by image recognition of pupil or iris. A measurement can be corrected or discarded depending on a position or a movement of the eye detected by the fixation unit. The measurement may be performed simultaneously by one or more of the other ophthalmic units. The position of the eye or the movement of the eye can be controllable by the fixation target or a virtual image thereof. The fixation target or its virtual image may be moveable. An accommodation state of the eye may be controllable by the accommodation target or a virtual image thereof. The accommodation target or its virtual image can be shiftable in focal length.

“The optical branch of the fixation unit, i.e., the optical branch coupled to the fixation unit, may pass straight through the optical branch coupler. Alternatively, the ophthalmic unit inserting output radiation for ophthalmic treatment may be arranged on a straight line extending the optical path. In both cases, the other optical branches may extend laterally to the optical path. Accordingly, the number of reflections on the optical branch passing straight through the optical branch coupler can be minimized. Minimizing the number of reflections may be advantageous for analyzing captured radiation of low intensity or emitting output radiation of high intensity. ‘Low’ may relate to 5% or less, e.g., 1%, of an cornea illumination intensity. ‘High’ may relate to 50% or more of a cornea ablation intensity or disruption intensity.

“One of the ophthalmic units may be an Optical Coherence Tomography (OCT) unit. The OCT unit may be adapted to perform an OCT measurement. The OCT unit may comprise a low-coherence light source (e.g., a Light Emitting Diode (LED), a broadband light source, a Supercontinuum Light Source, Swept source, e.g. for Time Encoded Frequency Domain OCT, a Ti: Sapphire laser, or a Superluminescent Diode (SLD)) and an interferometer. As a result, a map of cornea thickness can be determined, e.g., by means of Optical Low-Coherence Reflectometry (OLCR), which is also referred to as Optical Coherence Pachymetry (OCP) in this context.

“Optical lengths of the optical branches in the multibranched dichroic prism may be different. The different optical lengths of the respective optical branches may correspond to different penetration depths or measurements layers of the OCT measurement. Based on two different optical lengths of two respective optical branches, spatially separated sections are simultaneously detectable, such as spatially separated anatomies or tissues, particularly the anterior segment and the posterior segment of the eye, e.g., two or more of cornea, lens, retina, and other anatomies.

“One or more of the ophthalmic units may be a wavefront unit adapted to measure a wavefront of the capture radiation. The wavefront unit may comprise a wavefront light source and a lenslet array. For example, the wavefront unit and the OCT unit may share a broadband light source. Consequently, the OCT unit and the wavefront unit may be reduced in size, thus allowing for a still more compact design of the device. The wavefront unit may further comprise a narrowband filter, which may be applied to the light source when the wavefront unit is operated.

“The retina and/or the macula of an eye may be inspected using OCT. Alternatively or in addition, the retina and/or the macula of the eye may be detected using OCT for determining an optical length or physical length of an axis of the eye or for detecting an Age-related Macular Degeneration (AMD). Alternatively or in addition, the retina and/or the macula of the eye may be traced for the aforementioned fixation of the eye.

“Alternatively or in addition, one or more of the ophthalmic units may be a Scheimpflug unit adapted to perform a Scheimpflug measurement. The Scheimpflug measurement may provide at least one of values of height of an anterior chamber of the eye, a map of refractive power, a posterior corneal shape, and corneal thickness. The lens, i.e. a contour and/or a shape of the lens, of an eye may be measured using OCT. The shape of the lens may be an optically effective shape.

“One or more of the ophthalmic units may be a corneal topography unit adapted to measure a topography of a cornea surface, particularly an anterior cornea surface, of the eye. Alternatively or in addition, one or more of the ophthalmic units may be a keratometer unit adapted to determine a curvature of a cornea surface, particularly an anterior cornea surface, of the eye.

“Moreover, one or more of the ophthalmic units may be an illumination unit adapted to generate radiation for a slit illumination of the eye. At least one of the corneal topography unit, the keratometer unit and the illumination unit may comprise a projector adapted to generate output radiation projecting an intensity pattern. Two or more of the Scheimpflug unit, the corneal topography unit, the keratometer unit and the illumination unit may share one projector. The projector may comprise a microdisplay or a micromirror array.

“The device may further comprise a controller adapted to control each of the plurality of ophthalmic units. The projector may be adapted to project the intensity pattern in response to a digital image signal provided by the controller. The controller may be further adapted to compute optimized values based on results determined by two or more of the ophthalmic units. The optimization may include computing an average of the results or a maximum likelihood computation of the results. The results of the different ophthalmic units may be weighted according to accuracy or precision. The accuracy or precision may be determined by the ophthalmic units and/or the individual results. The different ophthalmic units may apply different ophthalmic technologies.”

The claims supplied by the inventors are:

“The invention claimed is:

“1. An ophthalmic system, comprising: a fixation target on a first optical path that is co-axial with an eye; an Optical Coherence Tomography (OCT) system in a first optical branch of the ophthalmic system on a second optical path, the OCT system adapted to perform an OCT measurement of an eye and output an OCT signal; a wavefront aberrometer in a second optical branch of the ophthalmic system on a third optical path, the wavefront aberrometer adapted to measure a wavefront of the eye and output a wavefront signal; a first partially transmissive mirror for coupling the third optical path with the second optical path; a digital camera in a third optical branch of the ophthalmic system on a forth optical path, the digital camera adapted to capture a digital image of the eye and output a digital image signal; an optical branch coupler comprising: a second partially transmissive mirror positioned on the first optical path and the second optical path and coupled with a first actuator for pivoting the second partially transmissive mirror between a first angular position and a second angular position; and a third partially transmissive mirror positioned on the first optical path and the third optical path and coupled with a second actuator for pivoting the third partially transmissive mirror between a third angular position and a fourth angular position, wherein a transmittance of the second partially transmissive mirror and a transmittance of the third partially transmissive mirror provides a spectral splitting of radiation in the first optical path between the optical branch coupler and the eye at a wavelength below 500 nm, in the first optical path between the optical branch coupler and the fixation target at a wavelength between 500 nm and 750 nm, and the second optical path at a wavelength above 750 nm; and a controller electrically coupled to the OCT system, wavefront aberrometer, and digital camera, the controller comprising a central processing unit (CPU) and a graphics engine adapted to: receive the OCT signal, the wavefront signal, and the digital image signal; generate a three-dimensional image of an anterior segment of the eye based on the received OCT signal; compute values for a sphere component, a cylinder component, and an axial component of the cylindrical component of a refractive power of the eye based on each of the received OCT signal, the received wavefront signal, and the received digital image signal; and output the three-dimensional image of the eye, together with the values for the sphere component, the cylinder component, and the axial component of the cylindrical component of the refractive power of the eye.

“2. The ophthalmic system of claim 1, wherein: the OCT system is adapted to perform an OCT measurement of the eye and output an OCT signal during a surgical procedure; the wavefront aberrometer is adapted to measure the wavefront of the eye and output a real-time wavefront signal during the surgical procedure; the digital camera adapted to capture a digital image of the eye and output a real-time digital image signal during the surgical procedure; and the controller is adapted to compute values for the determined sphere component, cylinder component, and axial component of the cylindrical component based on the received real-time OCT signal and the received real-time wavefront signal.

“3. The ophthalmic system of claim 1, wherein the controller is further adapted to determine one or more of a cornea thickness, a corneal curvature, an anterior chamber depth, a lens position, a lens thickness, a lens contour, a lens shape, an axial length, and a retina thickness of the eye, based on at least one of the received OCT signal and the received wavefront signal.”

For the URL and additional information on this patent, see: Donitzky, Christof; Wuellner, Christian. Integrated Device For Ophthalmology. U.S. Patent Number 10,582,851, filed October 5, 2017, and published online on March 23, 2020. Patent URL: http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=10,582,851.PN.&OS=PN/10,582,851RS=PN/10,582,851

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