WO2012151172A2 - Image-processor-controlled misalignment-reduction for ophthalmic systems - Google Patents

Image-processor-controlled misalignment-reduction for ophthalmic systems Download PDF

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Publication number
WO2012151172A2
WO2012151172A2 PCT/US2012/035927 US2012035927W WO2012151172A2 WO 2012151172 A2 WO2012151172 A2 WO 2012151172A2 US 2012035927 W US2012035927 W US 2012035927W WO 2012151172 A2 WO2012151172 A2 WO 2012151172A2
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WO
WIPO (PCT)
Prior art keywords
misalignment
image
ophthalmic
fixation light
light
Prior art date
Application number
PCT/US2012/035927
Other languages
French (fr)
Other versions
WO2012151172A3 (en
Inventor
Tibor Juhasz
Ferenc Raksi
Guy Holland
Original Assignee
Alcon Lensx, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Alcon Lensx, Inc. filed Critical Alcon Lensx, Inc.
Priority to EP12720361.0A priority Critical patent/EP2680740B1/en
Priority to JP2014509349A priority patent/JP5795684B2/en
Priority to AU2012250897A priority patent/AU2012250897B2/en
Priority to CA2832093A priority patent/CA2832093C/en
Priority to MX2013012626A priority patent/MX336512B/en
Priority to KR1020137031988A priority patent/KR101640536B1/en
Priority to RU2013153220/14A priority patent/RU2593745C2/en
Priority to ES12720361.0T priority patent/ES2610562T3/en
Priority to CN201280021411.8A priority patent/CN103687532B/en
Publication of WO2012151172A2 publication Critical patent/WO2012151172A2/en
Publication of WO2012151172A3 publication Critical patent/WO2012151172A3/en

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Classifications

    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B7/00Mountings, adjusting means, or light-tight connections, for optical elements
    • G02B7/003Alignment of optical elements
    • G02B7/004Manual alignment, e.g. micromanipulators
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B3/00Apparatus for testing the eyes; Instruments for examining the eyes
    • A61B3/10Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions
    • A61B3/13Ophthalmic microscopes
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B3/00Apparatus for testing the eyes; Instruments for examining the eyes
    • A61B3/10Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B3/00Apparatus for testing the eyes; Instruments for examining the eyes
    • A61B3/10Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions
    • A61B3/14Arrangements specially adapted for eye photography
    • A61B3/15Arrangements specially adapted for eye photography with means for aligning, spacing or blocking spurious reflection ; with means for relaxing
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B3/00Apparatus for testing the eyes; Instruments for examining the eyes
    • A61B3/10Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions
    • A61B3/14Arrangements specially adapted for eye photography
    • A61B3/15Arrangements specially adapted for eye photography with means for aligning, spacing or blocking spurious reflection ; with means for relaxing
    • A61B3/152Arrangements specially adapted for eye photography with means for aligning, spacing or blocking spurious reflection ; with means for relaxing for aligning
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B7/00Mountings, adjusting means, or light-tight connections, for optical elements
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B7/00Mountings, adjusting means, or light-tight connections, for optical elements
    • G02B7/003Alignment of optical elements
    • G02B7/005Motorised alignment
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B3/00Apparatus for testing the eyes; Instruments for examining the eyes
    • A61B3/10Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions
    • A61B3/102Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions for optical coherence tomography [OCT]

Definitions

  • This patent document relates to systems and techniques for ophthalmic imaging.
  • this patent document relates to systems and methods for providing an electronically controlled fixation light for improving a precision of aligning or docking an ophthalmic imaging system to a patient's eye.
  • a variety of advanced imaging devices have been developed over the years for ophthalmic imaging, diagnostics and surgery. For some applications, these imaging devices perform best when their optical axis is aligned with an optical axis of the imaged eye. Once the optical axis of the eye is aligned with the optical axis of the imaging device, some imaging devices enhance the precision of the imaging process by immobilizing the eye in the aligned position with the help of a patient interface or eye-docking system. As the precision of the imaging devices improves, the demand for eye-docking systems which provide more precise alignment also increases.
  • the alignment is guided manually.
  • the operator can direct the patient verbally, manually orient the eyeball, or adjust portions of the imaging device, such as its objective or gantry, or any combination of the above.
  • the patient interface often ends up docked to the eye in an ofl-center position, the eye's optical axis tilted and the eye laterally misplaced relative to that of the imaging system.
  • Some imaging systems use guidance mechanisms that promise improvements for the alignment process.
  • the alignment is aided by a fixation light.
  • the fixation light can be centered with the optical axis of the imaging system.
  • the patient can be instructed to train his eye on the fixation light. This fixation can align the patient's eye with the imaging system.
  • fixation light systems have limitations.
  • This patent document discloses fixation light controller systems with improved functionalities.
  • the eye of the patients typically has both lateral and angular misalignment relative to the imaging system.
  • Simply looking at a fixed fixation light centered with the optical axis of the imaging device does not eliminate both types of misalignments.
  • the fixation light is not fixed and can be manually or mechanically adjusted.
  • the precision of these fixation lights is considerably less than the precision of the imaging systems. Further, such mechanical adjustments can be quite time consuming and frustrating because of their limited precision.
  • fixation light may be controlled in part manually and in part electronically.
  • manual operations may improve the alignment, in other cases such system may still lack the required precision.
  • ophthalmic system may include an ophthalmic imaging device configured to generate an image of a portion of an imaged eye of a patient, an image processor, configured to determine a misalignment of the imaged eye and the imaging device by processing the generated image, and to generate a control signal according to the determined
  • misalignment-reduction system configured to receive the control signal, and to generate a misalignment-reduction response.
  • the ophthalmic imaging device can include an electronic sensing system that senses a collected imaging light from the imaged eye, including at least one of a Charge-Coupled Device (CCD) array, a Complementary Metal- Oxide Semiconductor (CMOS) array, a pixel-array, and an electronic sensor array, and an electronic display system that displays the image of a portion of the imaged eye in relation to the sensed collected imaging light, including at least one of a Light Emitting Diode (LED) display, a plasma screen, an electronic display, a computer display, a Liquid Crystal Display (LCD) screen, a Cathode Ray Tube (CRT) display, a video-module, a video microscope display, a stereo video microscope display, a high definition (HD) video microscope, a processor-based image system, an opto-mechanical projector of the electronic or digital type, and a light-source movable by an electro-mechanical actuator.
  • a Charge-Coupled Device CCD
  • CMOS Comp
  • the image processor is configured to identify an ophthalmic structure in the image, and to determine a measure of misalignment by determining a location of the ophthalmic structure relative to a reference of the imaging device. In some implementations the image processor is configured to identify the ophthalmic structure by determining a high-gradient line in the image, separating image elements with substantially different brightness or color.
  • the image processor is configured to fit at least one of a circle and an ellipse to the high-gradient line by measuring radial distances between the high-gradient line and the circle or ellipse, to determine a location coordinate of the fitted circle or ellipse by minimizing a measure of the radial distances, and to determine a misalignment-measure by relating the determined location coordinate and a coordinate of the reference.
  • the image processor is configured to determine a high-contrast line in the image, to determine misalignment distances between the high- contrast line and a targeting pattern, and to determine a misalignment-measure from the misalignment distances.
  • the reference of the imaging device is at least one of an objective, a patient module, a docking tip, an interface, a contact lens, a pupil, a viewing frame, a reference frame, and an internal lens of the ophthalmic system, and the imaging device is configured to generate a reference pattern related to the reference to assist the image processor to determine the misalignment of the imaged eye and the imaging device.
  • the recognized ophthalmic structure is a limbus of the imaged eye. In some implementations at least a portion of the image processed by the image processor is not displayed by the imaging device.
  • the misalignment-reduction system can include a fixation light source, and the misalignment-reduction response comprises the fixation light source generating a fixation light in response to the received control signal.
  • the fixation light source is configured to generate the fixation light for a non-imaged eye of the patient, and to move the generated fixation light according to the received control signal to assist a reduction of a misalignment between the imaged eye and a reference-component of the ophthalmic system.
  • the fixation light source can include at least one of a LED array, a plasma screen, an electronic display, a computer display, an LCD screen, a video-module, an opto-mechanical projector of the electronic or digital type, a CRT display, a slit-lamp, a processor-based image system, and a light-source movable by an electro-mechanical actuator.
  • the fixation light source is configured to generate the fixation light to guide the patient to reduce an angular misalignment.
  • the image processor is configured to determine the angular misalignment by fitting an ellipse to a high-contrast line of the image, and analyzing at least one of an aspect ratio and an area of the fitted ellipse.
  • the fixation light source can include a collimator to generate a fixation light to guide the patient to reduce a lateral misalignment.
  • the misalignment-reduction system can include a gantry, configured to move a movable portion of the imaging device, and a gantry controller, configured to receive the control signal from the image processor, and to move the gantry according to the received control signal, and the misalignment-reduction response can include the gantry controller moving the gantry and thus the movable portion of the imaging device to reduce a lateral misalignment.
  • the gantry is also part of the ophthalmic imaging device.
  • the misalignment-reduction system can include a support-gantry, configured to move a patient support relative to the imaging device, and a gantry controller, configured to receive the control signal from the image processor, and to move the support-gantry according to the received control signal, and the misalignment-reduction response can include the gantry controller moving the support-gantry and thus the patient support to reduce a lateral misalignment.
  • the image processor is configured to determine an angular and a lateral misalignment by processing the image, and the misalignment- reduction system can include only one of a fixation light source and a gantry controller.
  • the image processor is configured to determine an angular and a lateral misalignment by processing the image
  • the misalignment- reduction system can include a fixation light source, a gantry and a gantry controller.
  • the image processor is configured to determine an angular and a lateral misalignment by processing the image and a misalignment information.
  • the imaging system can include a locator light source, configured to project a locator light on the imaged eye, and the image processor is configured to identify an apical reflected locator light in the image generated by the imaging device, and to determine the misalignment information by analyzing the apical reflected locator light.
  • the misalignment information is at least one of an angular misalignment information, related to a vector in the image between the apical reflected locator light and a location of an imaged ophthalmic structure, and a lateral misalignment information, related to a vector in the image between a reference of the imaging system and at least one of the apical reflected locator light and the location of an imaged ophthalmic structure.
  • the ophthalmic system is configured to reduce the angular misalignment by adjusting the fixation light source, and to reduce the lateral misalignment by operating the gantry controller.
  • the fixation light is adjustable so that the locator light and a location of an imaged ophthalmic structure can be aligned by adjusting the fixation light.
  • the fixation light source and the locator light source are capable of operating at different wavelengths.
  • the locator light is invisible for the imaged eye.
  • a patient interface is configured to dock to the imaged eye of the patient after the misalignment-reduction system executed the
  • the misalignment-reduction system can include a fixation light source, configured to generate a fixation light for the imaged eye of the patient, and to adjust the generated fixation light according to the received control signal to assist a reduction of a misalignment between the imaged eye and a reference-component of the ophthalmic system.
  • Some implementations include a locator light, focusable to a second focal point different from a first focal point of the fixation light.
  • a method of aligning an eye with an ophthalmic system can include generating an image of a portion of an imaged eye of a patient by an ophthalmic imaging device, determining a misalignment of the imaged eye and the imaging device by an image processor processing the generated image, and generating a misalignment-reduction response electronically by a misalignment-reduction system based on the determined misalignment.
  • the determining the misalignment can include identifying an ophthalmic structure in the image, and determining a location of the ophthalmic structure relative to a reference of the imaging device.
  • the generating the misalignment-reduction response can include generating a fixation light by a fixation light source according to the determined misalignment.
  • the generating the fixation light can include generating the fixation light to guide the patient to reduce an angular misalignment. In some implementations the generating the fixation light can include generating a fixation light to guide the patient to reduce a lateral misalignment, wherein the fixation light source can include a collimator.
  • the generating the fixation light can include generating the fixation light for a non-imaged eye of the patient, and the generating the misalignment-reduction response can include adjusting the fixation light according to the determined misalignment to assist the patient to reduce the misalignment.
  • the generating the fixation light can include generating the fixation light for the imaged eye of the patient, and the generating the misalignment-reduction response can include adjusting the fixation light according to the determined misalignment to assist the patient to reduce the misalignment.
  • the generating the misalignment-reduction response can include moving a gantry of the imaging system by a gantry controller to reduce a lateral misalignment.
  • the determining the misalignment can include determining an angular and a lateral misalignment by the image processor processing the image and a misalignment information
  • the generating the misalignment-reduction response can include adjusting a fixation light of a fixation light system and a gantry controller.
  • the determining the misalignment can include projecting a locator light onto the imaged eye by a locator light system, locating an apical reflected locator light in the image generated by the imaging device, and determining the misalignment information using the located apical reflected locator light.
  • the determining the misalignment information can include determining an angular misalignment information, related to a vector in the image between the apical reflected locator light and a location of an imaged ophthalmic structure, and determining a lateral misalignment information, related to a vector in the image between a reference of the imaging system and at least one of the apical reflected locator light and the imaged ophthalmic structure.
  • the generating the misalignment-reduction response can include reducing the angular misalignment by adjusting the fixation light, and reducing the lateral misalignment by operating the gantry controller.
  • the reducing the angular misalignment and the reducing the lateral misalignment are repeated iteratively.
  • the generating the misalignment-reduction response can include projecting the fixation light into the imaged eye, and reducing the lateral and the angular misalignment by causing the head of the patient to move laterally to align the locator light and the fixation light.
  • an ophthalmic system can include an imaging device that generates an image of an imaged eye of a patient, an image processor that determines an angular and a lateral misalignment of the imaged eye and the imaging device by processing the generated image, a fixation light system that projects a fixation light on an eye of the patient to assist a reduction of the angular misalignment, and a gantry that adjusts a movable optic of the system to reduce the lateral misalignment.
  • the ophthalmic system can include an indicator light system that projects an indicator light on the imaged eye to provide a misalignment information for the image processor.
  • FIG. 1 illustrates an eye
  • FIG. 2 illustrates an ophthalmic imaging system
  • FIGS. 3A-C illustrate misalignments of the eye.
  • FIG. 4 illustrates an ophthalmic system with a misalignment reduction system.
  • FIGS. 5A-E illustrate an image processing system.
  • FIGS. 6A-B illustrate a fixation light system.
  • FIGS. 7A-C illustrate a misalignment reduction method.
  • FIGS. 8A-B illustrate misalignment reduction with a fixation light.
  • FIGS. 9A-B illustrates an image processing method to determine an angular misalignment.
  • FIGS. 10A-B illustrate a collimated fixation light system.
  • FIG. 11 illustrates a misalignment reduction system with a gantry.
  • FIGS. 12A-B illustrate an operation of the gantry system.
  • FIG. 13 illustrates a bed gantry system
  • FIG. 14 illustrates a system combining a fixation light and a gantry.
  • FIGS. 15A-B illustrate an operation of the fixation light-and-gantry system.
  • FIGS. 16A-B illustrate a system with a locator light.
  • FIGS. 17A-B illustrate a locator light system processing an angular and a lateral misalignment.
  • FIG. 18 illustrates the reduction of the lateral and angular misalignment.
  • FIGS. 19A-B illustrate a fixation light system, projecting the fixation light into the imaged eye of the patient.
  • FIGS. 20A-B illustrate a system with two fixation lights.
  • FIG. 21 illustrates a system with an additional OCT imaging system.
  • FIG. 22 illustrates a method of operating the ophthalmic system with the misalignment reduction system.
  • Implementations and embodiments in this patent document provide a fixation light system for ophthalmic imaging devices for increasing the precision of the alignment of the imaged eye and the imaging device.
  • FIG. 1 illustrates a human eye 1 in some detail.
  • the eye 1 includes a cornea 2 that receives and refracts the incoming light, an iris 3, a pupil 4, in effect an opening for the light to enter the inner eye, and a lens 5 that focuses the light on the retina.
  • the eye 1 includes a limbus 6, delineating the boundary between the colored iris 3 and a white sclera 7.
  • FIG. 2 illustrates an ophthalmic imaging system 10 and its operation.
  • a patient 8 can be laid on a supporting bed.
  • An imaging light source 1 1 can shine an imaging light on an imaged eye l i.
  • a portion of the imaging light reflected by the imaged eye l i can be collected by an objective 12 and guided as a collected imaging light 13 to an optic or optical system 14.
  • the optic 14 can guide the collected imaging light 13 to an imaging module 15.
  • a surgeon or medical professional can analyze the image provided by the imaging module 15 and give instructions to the patient to move the imaged eye 1 i to improve its alignment with an optical axis of the imaging system 10. In other cases, the surgeon can manipulate the imaged eye li manually to improve the alignment.
  • ophthalmic imaging system 10 provides the surgeon only with an image of limited precision as the alignment with the eye is only approximate.
  • FIGS. 3A-B illustrate that after the use of such a limited precision ophthalmic imaging system 10, a residual misalignment between the eye 1 and the ophthalmic imaging system 10 can persist.
  • a distal end 20 of the ophthalmic system 10 can be the objective 12, or a contact module, a docking unit, a distal tip, an interface, or an applanation module.
  • the distal end 20 can include a housing 21 that supports a distal lens 22.
  • An optical axis 28 of the ophthalmic imaging system 10 typically shared with an optical axis of the distal lens 22, can remain misaligned with an optical axis 9 of the eye 1 even after the above limited-precision docking procedure has been performed.
  • FIG. 3A illustrates that the misalignment can be a lateral misalignment characterized by a ( ⁇ , ⁇ ) vector between the optical axis 9 of the eye and the optical axis 28 of the imaging system 10, lying approximately in the lateral plane perpendicular to the optical axis 28.
  • FIG. 3B illustrates that the misalignment can also be an angular misalignment.
  • the angular misalignment can be characterized by the ( ⁇ , ⁇ ) Euler angles between the optical axis 9 of the eye and the optical axis 28 of the imaging system 10.
  • the misalignment can be a combination of a lateral and an angular
  • FIG. 3C illustrates that on an imaging interface of the imaging module 15 either misalignment can appear as a displacement of the iris 3 and pupil 4 relative to a targeting pattern 17, such as a target circle.
  • the surgeon can give verbal instructions to the patient to move the imaged eye 1 i, or to manipulate the eye 1 i manually based on this displayed displacement.
  • fixation light devices can utilize a fixation light to provide guidance for the patient.
  • fixation light devices still have shortcomings as discussed above.
  • Some devices provide adjustable fixation lights as an improvement.
  • the location of the fixation light is typically adjusted manually or mechanically, still resulting in an adjustment process with limited precision.
  • FIG. 4 illustrates an ophthalmic imaging system 100 that can be used to align the imaged eye 1 i and the ophthalmic system 100 with improved precision.
  • the ophthalmic system 100 can include an ophthalmic imaging device 1 10, an image processor 120 and a misalignment reduction system 130.
  • the ophthalmic imaging device 1 10 can be configured to generate an image of a portion of an imaged eye of a patient.
  • the image processor 120 can be configured to determine a misalignment of the imaged eye and the imaging device by processing the generated image, and to generate a control signal according to the determined misalignment.
  • the misalignment-reduction system 130 can be configured to receive the control signal and to generate a misalignment-reduction response.
  • the ophthalmic imaging device 1 10 can include an imaging light source 1 1 1 that provides an imaging light for the imaged eye l i.
  • the imaging light source 1 1 1 can be a single light, a ring of e.g. 4, 6 or 8 lights, or a light source with a continuous ring shape.
  • An objective 1 12 can collect a fraction of the imaging light, returned by the imaged eye l i, and direct it as a collected imaging light 1 13 to an optic 1 14.
  • the optic 1 14 can guide the collected imaging light 1 13 towards an imaging module 1 15.
  • the optic 1 14 can be quite complex, including a large number of lenses and mirrors.
  • the optic 1 14 can also be multifunctional, for example also configured to guide a surgical laser beam to the imaged eye li.
  • the imaging module 1 15 can provide an image for an operator of the imaging system 100 via an imaging interface.
  • the ophthalmic imaging device 1 10 can include a microscope, an ophthalmic microscope, or a stereo microscope.
  • An imaging interface of these microscopes can include the eyepiece of these microscopes.
  • the ophthalmic imaging device 1 10 can generate the image at least in part electronically.
  • the imaging module 1 15 of the ophthalmic imaging device 1 10 can include an electronic sensing system that senses the collected imaging light 1 13.
  • the electronic sensing system can include a Charge-Coupled Device (CCD)-array, a Complementary Metal Oxide Semiconductor (CMOS) array, a pixel-array, or an electronic sensor array to sense the collected imaging light 1 13.
  • CCD Charge-Coupled Device
  • CMOS Complementary Metal Oxide Semiconductor
  • the imaging module 1 15 can also include an electronic display system as an imaging interface.
  • This electronic display can display an electronic image of a portion of the imaged eye li based on the sensed light 1 13.
  • This electronic display or imaging interface can be, for example, a Light Emitting Diode (LED), an organic LED (OLED) display, an active matrix OLED (AMOLED) display, a plasma screen, an electronic display, a computer display, a Liquid Crystal Display (LCD) screen, a Cathode Ray Tube (CRT) display, a video-module, a video microscope display, a stereo video microscope display, a High Definition (HD) video microscope, a processor- based image system, an opto-mechanical projector of the electronic or digital type, or a light-source movable by an electro-mechanical actuator.
  • the above elements of the imaging systems can be combined.
  • the ophthalmic imaging device 1 10 can include an optical coherence tomographic (OCT) imaging system, as described in relation to FIG. 21.
  • OCT optical coherence tomographic
  • the misalignment reduction system 130 may include the objective 1 12, in others portions of the optic 1 14.
  • the image processor 120 can be configured to identify an ophthalmic structure in the image, generated by the imaging device 1 10, and to determine a location of the ophthalmic structure relative to a reference of the imaging device.
  • the reference of the imaging device can be the objective 1 12, a patient module, a docking tip, an interface, a contact lens, a pupil, a viewing frame, a reference frame, and an internal lens of the ophthalmic system.
  • the imaging module 1 15 can be configured to generate a reference pattern related to the reference to assist the image processor to determine the misalignment of the imaged eye and the imaging device.
  • a targeting circle similar to the targeting pattern 17 can be such a reference pattern.
  • Other reference patterns may include cross hairs, multiple circles and their combinations.
  • the image processor 120 may be configured to recognize the limbus 6 as the ophthalmic structure.
  • the image processing may be based on the pupil 4 as well, but often the limbus 6 forms a more regular circle and thus is well suited for the image processing.
  • FIGS. 5A-E illustrate that in operation, the image processor 120 can first identify one or more ophthalmic structures of the imaged eye l i e.g. by analyzing the contrast or gradient of the nearby pixels of the image.
  • FIG. 5A illustrates that the image processor 120 may perform a radial scan of the image and record the pixels' brightness, color or both along the scan.
  • the center of the radial scan can be chosen in different ways. Also, non-radial scans, such as circular, linear, rectangular, mesh-type, 2D and many other types of scans can be used.
  • the image processor 120 can identify a high-gradient or high-contrast pixel 121 along the scan as the pixel where the recorded brightness or color varies the fastest.
  • a high-contrast or high-gradient line 122 can be defined by connecting the high- gradient/contrast pixels of nearby scans.
  • Such a high-gradient/contrast line can separate ophthalmic regions with strongly differing brightness or color and thus can be a useful indicator of ophthalmic structures, such as the limbus 6 or the pupil 4.
  • Numerous other methods of machine-vision and image processing are known in the arts to determine structures and their boundaries, which can be used in place of the above described high- gradient/contrast method.
  • FIG. 5B illustrates that subsequently the image processor 120 can fit probe- functions, such as fitting circles 124 or ellipses to the identified high-gradient/contrast lines to identify circular ophthalmic structures, such as the limbus 6 or the pupil 4.
  • the fitting can take several forms. In some cases, the center and radius of the fitting circle 124 can be moved so that the fitting circle overlays the high-gradient/contrast line with the highest precision. The precision can be quantified e.g.
  • FIG. 5B illustrates a 4-ray implementation, where the average radial distance is defined as
  • the center coordinates (Cx,Cy) of the shifted fitting circle 124' essentially coincide with the coordinates (Ox,Oy) of the center of the ophthalmic structure, corresponding to the high-gradient/contrast line 122.
  • This approach can be terminated when the shifted fitting circle 124' becomes concentric with the ophthalmic structure 122, but the radii of the two structures remain different.
  • the image processor 120 may be able to fit a fitting circle 124 to the high-gradient/contrast line 122 with or without adjusting its radius and thus conclude that the ophthalmic structure indicated by the high contract line 122 is circular.
  • the image processor 120 may determine that the color of the pixels changes from white to non-white across the high-gradient/contrast line 122.
  • the image processor 120 determines the coordinates of the center of the limbus 6, since the limbus 6 is concentric with the shifted fitting circle 124' and thus the center of the limbus 6 is located at the same (Cx,Cy) coordinates as the center of the shifted fitting circle 124'. Therefore, the image processor 120 can determine a misalignment vector 143 that connects the (Cx,Cy) coordinates of the center of the limbus 6 to the known center coordinates of a targeting pattern 1 17.
  • the misalignment vector 143 may be used by a misalignment reduction system 130 to reduce the
  • FIGS. 6A-B illustrate an implementation of the ophthalmic imaging system 100 where the misalignment reduction system 130 includes a fixation light source 140.
  • the fixation light source 140 can project a fixation light 145 into a non-imaged control eye l c of the patient 8.
  • the patient 8 can be instructed to focus on or follow the fixation light 145 with the control eye l c.
  • the misalignment reduction response of the misalignment reduction system 130 can be an adjustment of the fixation light 145.
  • the imaging module 1 15 can assist the determination of a misalignment of the imaged eye l i and a reference-component of the ophthalmic imaging device 1 10 by simultaneously displaying an image portion of the imaged eye l i and the reference or targeting pattern 1 17, such as a target circle, via its imaging interface.
  • the reference-component of the imaging device 1 10 can be the objective 1 12, a patient module, a docking tip, an interface, a contact lens, a pupil, a viewing frame, a reference frame, an internal lens of the ophthalmic system, or any equivalents.
  • the location or display of the targeting pattern 1 17 can be fixed to the reference-component, in effect indicating the position of the reference-component.
  • the simultaneous display of the image portion of the imaged eye l i and the targeting pattern 1 17 by the imaging module 1 15 can effectively assist the determination of the misalignment of the imaged eye li.
  • the image processor 120 can analyze the simultaneously displayed image portion of the imaged eye l i and the target pattern 1 17 and compute the misalignment. The details of computing the misalignment were described above extensively.
  • the image processor 120 can summarize the computed direction and magnitude of the misalignment by generating the misalignment vector 143. Based on this misalignment vector 143, the image processor 120 can compute a misalignment reduction vector 144 to be used by the misalignment reduction system 130 to reduce or eliminate the computed misalignment.
  • the misalignment reduction vector 144 need not be the same or simply opposite as the misalignment vector 143, as it represents how the misalignment reduction system is to be adjusted to reduce or eliminate the misalignment.
  • the misalignment reduction vector 144 also depends on the distance of the misalignment reduction system 130 from the eye 1 and on other factors and thus can refer to a large variety of misalignment reduction measures.
  • the image processor 120 can generate a fixation light control signal for the fixation light source 140 according to the determined misalignment reduction vector 144.
  • the image of the eye portion and the targeting pattern 1 17 are not necessarily displayed. Rather, they can be provided for the image processor 120 by the imaging device 1 10 in an electronic form only, invisible for the system operator or surgeon.
  • Some image processors 120 do not utilize the fitting circle 124 of FIGS. 5B-E. Instead, these implementations can (a) directly determine misalignment distances ⁇ * 1 ... ⁇ * ⁇ between the high-contrast line 122 and the targeting pattern 1 17 along n rays, as described above, where n is an integer; and (b) perform a search algorithm to find a misalignment of the ophthalmic structure corresponding to the high-contrast line 122 relative to the targeting pattern 1 17 or another reference of the imaging system 100.
  • the search algorithm can be based e.g. on minimizing a misalignment- measure, such as the average misalignment ⁇ above, or on symmetrizing the misalignment distances ⁇ * 1 . .. ⁇ * ⁇ in opposing directions, among others.
  • the misalignment vector 143 can be determined to characterize the misalignment.
  • the image processor 120 can then compute the misalignment reduction vector 144 based on the determined misalignment vector 143 and output a fixation light control signal towards the fixation light source 140 corresponding to the misalignment reduction vector 144.
  • FIG. 7B illustrates that the fixation light source 140 can receive the fixation light control signal and generate, project, or display a fixation light 145 according to the received fixation light control signal.
  • the image processor 120 can compute the misalignment reduction vector 144f by which the fixation light 145 is to be adjusted to the lower right direction so that if the control eye lc follows the adjusted fixation light 145, the misalignment 143 of the imaged eye l i will be substantially reduced, or optimally even eliminated.
  • the fixation light source 140 can first generate and display the fixation light 145, and then move the displayed fixation light 145 according to the received fixation light control signal. Since the movements of the control eye lc and the imaged eye li closely track each other, as the control eye lc is moved by the patient according to the displayed fixation light 145, the imaged eye li moves in a correlated manner. Because of this correlation between the movements of the imaged eye l i and the control eye lc, the fixation light system 120 can assist the reduction of the misalignment of the imaged eye l i relative to the ophthalmic imaging system 1 10.
  • fixation light 145 may simply display the fixation light 145 by the fixation light source 140 at a properly chosen location according to the fixation light control signal, instead of moving it. In either of these embodiments, the patient can be instructed to follow, or focus on, the fixation light 145 with the control eye lc.
  • the fixation light source 140 can include a LED array, a plasma screen, an electronic display, a computer display, an LCD screen, a video-module, an optomechanical projector, a slit-lamp, a processor-based image system, or a light-source, movable by an electro-mechanical actuator.
  • FIG. 6B illustrates the appearance of the ophthalmic system 100 for the patient 8 in some embodiments.
  • the left panel shows that the imaged eye l i can see the objective 1 12, surrounded by e.g. six imaging light sources 1 1 1.
  • the right panel shows that the non- imaged/control eye l c can see the fixation light 145 displayed on the fixation light source 140.
  • the fixation light source 140 can be an LCD screen or an equivalent, and the fixation light 145 can be a bright spot displayed on the dark LCD screen 140.
  • some embodiments may include two fixation light sources 140, one on each side of the objective 1 12.
  • the image processor 120 may display the processed image e.g. for informing the medical technician or surgeon. In other implementations at least a portion of the image processed by the image processor 120 may not be displayed by the imaging system 100, only provided in electronic format to the image processor 120 by the imaging device 1 10.
  • FIGS. 8A-B illustrate the case when the eye's misalignment is purely angular, as was discussed in relation to FIG. 3B.
  • the optical axis 9i of the imaged eye l i may be rotated by the Euler angles ( ⁇ , ) relative to the optical axis 28 of the imaging system 100.
  • the optical axis 9c of the control eye l c may be rotated approximately by the same Euler angles ( ⁇ , ⁇ ) relative to the axis of the fixation light source 140, along which the fixation light 145 also propagates.
  • FIGS. 9A-B illustrate an operation of the image processor 120 configured to analyze the angular misalignment of FIGS. 8A-B.
  • the image processor 120 can identify the various ophthalmic structures of the imaged eye li, such as the limbus 6i, by identifying the high-gradient/contrast lines 122 of the image, as described above.
  • FIG. 9A illustrates that while an aligned limbus 6ia would appear as a circle, in the case of angular misalignment the rotated limbus 6ir appears elliptical from the viewpoint of the image processor 120.
  • the image processor 120 will not be successful fitting a fitting circle 124 as a probe function to the high- gradient/contrast line 122.
  • FIG. 9B illustrates that once the image processor 120 is unsuccessful fitting a fitting circle 124 then it can attempt to fit a fitting ellipse 124' to the high-gradient/contrast line 122' to identify the rotated limbus 6ir or the rotated pupil 4ir.
  • the aspect ratio a/c i.e. the ratio of the length of the minor and major axes of the fitting ellipse 124', can be used to determine the Euler angles ( ⁇ , ⁇ ) of angular misalignment of the imaged eye l i.
  • FIG. 8B illustrates that once the image processor 120 was successful determining the Euler angles ( ⁇ , ⁇ ) of the angular misalignment from the aspect ratio a/c of the fitting ellipse 124' fitted to the high-gradient/contrast line 122', it can compute the misalignment reduction vector 144fa with which the fixation light 145 should be moved on the fixation light source 140.
  • This misalignment reduction vector 144fa can be constructed so that if the control eye l c follows the fixation light 145 adjusted by the angular misalignment reduction vector 144fa, as indicated by the solid black arrow, the angular misalignment can be reduced, or possibly even eliminated.
  • the f label of the misalignment reduction vector 144fa indicates that the misalignment reduction system 130 is of the fixation light 140 type, and the a label refers to an angular misalignment.
  • FIGS. 10A-B illustrate a case of a lateral misalignment ⁇ .
  • the fixation light sources 140 can include a collimator 142 that can be configured to generate a fixation light 145 to guide the patient to reduce the lateral misalignment ⁇ efficiently.
  • the collimator 142 can generate a fixation light 145 with essentially parallel rays, as if it had been generated by a light source at infinity. Thus, the patient 8 can see this collimated fixation light 145 only if he/she looks up straight along the line of the fixation light 145.
  • the optical axis 9i of the imaged eye is parallel to the system optical axis 28.
  • the image processor 120 can determine a lateral misalignment ⁇ of the imaged eye from the analysis of the image of the imaged eye l i, and compute a corresponding misalignment reduction vector 144fl, the label 1 referring to the lateral misalignment in this fixation light system, referred to by the label f.
  • the image processor 120 then can generate a fixation light control signal representing the calculated
  • the fixation light source 140 can move or adjust the collimated fixation light 145 with the misalignment reduction vector 144fl, shown by the solid arrow.
  • the patient 8 can be instructed to move his/her head to find the adjusted collimated fixation light 145. In order to actually see the collimated fixation light 145, the patient 8 will have to move his/her head laterally until the lateral misalignment ⁇ is essentially eliminated.
  • FIG. 11 illustrates an implementation of the misalignment-reduction system 130 that includes a gantry controller 150, configured to receive the fixation light control signal from the image processor 120 and to move a gantry 155 accordingly, wherein the gantry 155 is configured to move a movable portion of the imaging device 1 10.
  • a motor or actuator, moving the gantry 155 can be part of either the gantry controller 150 or the gantry 155.
  • the movable portion of the imaging device 1 10 can be the objective 1 12 or a portion of the optic 1 14.
  • the misalignment-reduction response includes the gantry controller 150 moving the gantry 155 to reduce a lateral misalignment.
  • the gantry 155 can be part of the ophthalmic imaging device 1 10.
  • FIGS. 12A-B illustrate an operation of the gantry-based system of FIG. 11.
  • the primary purpose of the adjustment process is to reduce the lateral misalignment of the optical axis 9i relative to the optical axis 28 of the imaging device 1 10.
  • This lateral misalignment, or displacement can be characterized by the misalignment vector 143 (Ax,Ay), or the magnitude of this misalignment vector 143, ⁇ , as discussed e.g. in relation to FIG. 3A.
  • FIG. 12A illustrates that the image processor 120 may analyze the image of the imaged eye l i, determine the misalignment vector (Ax,Ay), then determine the corresponding misalignment reduction vector 144gl, and output a control signal to the gantry controller 1 50 representing the misalignment reduction vector 144gl.
  • the label g refers to the gantry type misalignment reduction system 130.
  • FIG. 12B illustrates that the gantry controller 150 can, in response to the control signal, move the gantry 155 with the lateral misalignment reduction vector 144gl to eliminate the lateral misalignment ⁇ and align the optical axis 9i of the imaged eye with the optical axis 28 of the imaging device 1 10.
  • misalignment-reduction system 130 may be able to reduce or eliminate both of these misalignments, as described next.
  • the image processor 120 may follow the method of FIG. 9 to compute the angular misalignment of the imaged eye l i.
  • the elliptic distortion of the limbus 6i can be caused both by the angular misalignment and by the lateral misalignment and these two effects need to be separated.
  • the image processor 120 can project the fixation light 145 at a suitable first location and the patient can be instructed to focus on this once- adjusted fixation light 145. From measuring the ellipticity of the limbus 6i, the knowledge of first location and the location of the eye on the imaging interface 1 15, the image processor 120 can determine the lateral and angular misalignments. Based on the determined lateral misalignment, the patient can be instructed to move the imaged eye 1 i to the center of the imaging device 1 10. This process may be performed iteratively to reach sufficient precision. Sometimes the fixation light 145 can be readjusted and the ellipticity re-measured to assist the process.
  • the image processor 120 may adjust the fixation light 145 for a second time, typically to a second location corresponding to the center of the imaging device 1 10.
  • the patient 8 focusing on this twice adjusted fixation light 145 can eliminate the angular misalignment as well.
  • the single-component gantry-based misalignment-reduction system 130 may be able to correct both types of misalignments in separate phases as well.
  • misalignments but did not eliminate them, the two phases can be repeated iteratively to substantially eliminate the two types of misalignments.
  • a large variety of optimization and other search algorithms can be used to facilitate such iterative approaches.
  • FIG. 13 illustrates an implementation of the misalignment-reduction system 130 that includes a movable patient support, such as a bed 168, moved by a support/bed gantry 165 that is controlled and moved by a bed gantry controller 160.
  • the gantry controller 160 can move the support/bed gantry 165 by a lateral misalignment reduction vector 144bl, which in turn moves the patient support/bed 168.
  • the b label stands for the bed 168.
  • aspects of this implementation include that the relative position of the optical elements in the imaging device 1 10 are not changed during regular operations, thus a high level of alignment and precision of the optics can be maintained. At the same time, the weight and physical extent of the patient support 168 is much greater than that of the objective 1 12, thus the high precision adjustment of the patient support 168 has its own challenges.
  • FIG. 14 illustrates that some implementations of the misalignment reduction system 130 may contain both a fixation light system 140-145 and a gantry system 150- 155. Such an integrated misalignment reduction system 130 may allow the surgeon to reduce and eliminate both types of misalignments in an efficient manner.
  • FIGS. 15A-B illustrate that in some embodiments, the image processor 120 may be able to determine the lateral and angular misalignments by the above described methods and direct the fixation light source 140 and the gantry controller 150 to reduce the misalignments.
  • FIG. 15A illustrates a typical situation, where the imaged eye has both a lateral misalignment ⁇ or (Ax, Ay) and an angular misalignment ( ⁇ , ).
  • the image processor 120 can be configured to analyze the image and compute a lateral misalignment reduction vector 1441 and an angular misalignment reduction vector 144a.
  • a lateral misalignment reduction vector 1441 and an angular misalignment reduction vector 144a As before, there are a large number of different measures of the misalignment, which can be expressed in terms of angular, linear, percentage and other variables.
  • the term "misalignment vector" can refer to any of these variables, measures and their combinations.
  • FIG. 15B illustrates that the patient can be instructed to follow the fixation light 145 that is adjusted by the angular misalignment reduction vector 144fa to eliminate the angular misalignment. Then the gantry controller 150 can adjust the gantry 1 55 with the lateral misalignment reduction vector 144gl to eliminate the lateral misalignment. Integrated embodiments with such a gantry 155 can reduce the lateral misalignment efficiently and with high precision as they do not rely on the patient moving the imaged eye laterally.
  • the two phases of alignment reduction can be performed in the opposite order or in alternating repeated phases.
  • the gantry can also be the support gantry 165, moving the patient support 168 instead of the objective 1 12 or the movable portion of the optic 1 14.
  • FIGS. 16A-B illustrate that in some integrated systems the image processor 120 may be configured to determine the angular and the lateral misalignment by processing the image and an additional misalignment information.
  • the misalignment information can be originated by a locator light source 170.
  • the locator light source 170 can generate a locator light 175 which can be coupled into the main optical pathway by a beam splitter 171.
  • the optic 1 14 and in particular the objective 1 12 can guide or project the locator light 175 onto the imaged eye li.
  • the imaged eye l i can be approximated by a reflecting sphere, or at least a portion of a reflecting sphere, then standard geometric considerations reveal that the portion of the locator light 175 that reflects back into the objective 1 12 parallel to the optical axis 28 is the one that is reflected from the apex of the spherical eye 1. This reflected light will be referred to as an apical reflected locator light 177. The other rays are shown to reflect away from the system optical axis 28.
  • FIG. 16B illustrates that an image 177i of the apical reflected locator light 177 can be detected by the image processor 120 in the overall image generated by the imaging device 1 10 on the imaging module 1 15, as shown by the white spot.
  • the white spot image of the apical reflected locator light 177i does not coincide with the system optical axis, indicated by the solid cross. It is noted though that the relative locations of the white spot and the black cross are independent from a possible angular misalignment of the image eye.
  • the vector connecting the imaged apical reflected locator light 177i with the cross-mark of the system optical axis 28 can provide the additional alignment information for the image processor 120 that enables it to determine the lateral misalignment independently from the angular misalignment.
  • FIGS. 17A-B illustrate that the imaged eye is more appropriately modeled as a primary sphere with a protruding secondary sphere, corresponding to the cornea 2.
  • Some implementations of the image processor 120 can be configured to determine the misalignment information by analyzing the imaged apical reflected locator light 177i on the basis of this more realistic model. For this analysis, the image processor 120 can use one or more fitting parameters, or the results of pre-procedure imaging measurements.
  • FIGS. 17A-B illustrate a generic case with simultaneous angular
  • misalignment ⁇ , ⁇ ) and lateral misalignment ⁇ If the imaged eye l i has only the lateral misalignment ⁇ , then the image spot of the apical reflected locator light 177i coincides with the center of the limbus 6ic, indicated by a solid x in FIG. 17B. This limbus center 6ic is not directly detected, but can be computed e.g. by fitting the fitting circle 124 to the image of the limbus 6i.
  • the vector or distance connecting the image spot of the apical reflected locator light 177i and the limbus center 6ic is an example of a dominantly or purely angular misalignment information that can be used by the image processor 120 to generate a misalignment reduction vector 144fa for the fixation light source 140 to correct this angular misalignment.
  • determining the lateral displacement ⁇ e.g. between the system optical axis 28 and the center lx of the imaged eye l i, may be more challenging when the complex shape of the eye is taken into account than the procedure in FIGS. 16A- B. Therefore, in a first phase, an operator of the system 100 may adjust the fixation light 145 and instruct the patient to focus on the adjusted fixation light 145 until the limbus center 6ic and the image spot of the apical reflected locator light 177i overlap or coincide, thus eliminating the angular misalignment and aligning the system optical axis 28 with the imaged eye's optical axis 9i.
  • the distance or vector between the system optical axis 28, indicated by the solid cross, and the overlapping image spot of the apical reflected locator light 177i and the limbus center 6ic (solid x) can provide a lateral misalignment information.
  • the image processor 120 may compute the lateral
  • misalignment reduction vector 144gl using this lateral misalignment information and send a corresponding control signal to the gantry controller 150.
  • the gantry controller 150 can adjust the gantry 155 with the lateral misalignment reduction vector 144gl.
  • FIG. 18 illustrates that some implementations of the misalignment reduction system 130 are configured to reduce or even eliminate both the angular and lateral misalignments by the above operations.
  • the lateral misalignment can be reduced by the movement of the imaged eye l i alone, or by the complementary lateral movement (Ax,Ay) of the imaged eye l i and (Ax',Ay') of the imaging device 1 10.
  • the operator of the ophthalmic system 100 may lower a patient interface 180, configured to dock to the imaged eye l i of the patient.
  • This patient interface 180 can immobilize the imaged eye l i to keep it fixed for subsequent procedures.
  • These procedures may include diagnostic procedures, imaging procedures and ophthalmic surgical procedures.
  • the objective 1 12 of the ophthalmic system 100 can include a distal objective lens 1 12- 1 , contained in an objective housing 1 12-2.
  • the patient interface 180 can include an interface lens, contact lens, sometimes also called applanation plate 180-1 , contained in an interface housing 1 80-2.
  • the patient interface 1 80 may be attached to the objective 1 12 or to the distal end of the imaging system 1 10.
  • part of the patient interface 1 80 can be attachable to the eye and the other part to the distal end of the imaging system 1 10.
  • the patient interface 180 can be attachable to the eye with a suction ring or vacuum skirt 180-3.
  • the patient interface 180 can be docked with the imaged eye l i after the alignment of the imaged eye l i with the imaging device 1 10 has been completed. In other embodiments, the patient interface 180 can be docked with the imaged eye 1 i in an iterative manner. First, the imaged eye 1 i can be brought into alignment with the imaging device 1 10. Second, the patient interface can be lowered onto the imaged eye l i to make contact, but still allowing the imaged eye l i some movement.
  • the alignment procedure can be repeated and one or more new misalignment reduction vectors can be computed by the image processor 120.
  • the imaged eye li can be realigned using the newly computed misalignment reduction vector(s).
  • FIGS. 19A-B illustrate that in some embodiments of the ophthalmic system 100', the fixation light source 140' can project the fixation light 145' not onto the control eye lc, but into the main optical pathway of the imaging device 1 10' with a beam splitter BS, so that the fixation light 145' is projected onto the imaged eye l i instead.
  • FIG. 19B illustrates the appearance of the embodiment 100' for the patient: the fixation light 145' appearing in the objective 1 12' itself, instead of a separate fixation light source 140' .
  • the patient may be instructed to follow the fixation light by the imaged eye li instead of the control eye lc.
  • the other elements of these embodiments 100' as well as the principles of their operation can be analogous or equivalent to the above described systems.
  • FIGS. 20A-B illustrate variations of the embodiment 100' of FIGS. 19A-B.
  • the locator light 175' can be used as a second fixation light.
  • the locator/second fixation light 175' can be focused to a second focal point 176, located at a z-coordinate z2 different from the z-coordinate zl of the first focal point 146 of the first fixation light 145'.
  • the z-coordinates of the fixation lights can be measured from a zO reference level along the optical pathway.
  • the z-coordinate zl of the first focal point 146 of the first fixation light 145' need not be at the distal end of the objective 1 12 as shown.
  • the patient 8 can be instructed to move and rotate the imaged eye l i to align the first fixation light 145' and the second fixation light 175', in effect to align the first focal point 146 and the second focal point 176. If the first and second focal points 146 and 176 both lie on the system optical axis 28, this procedure guides the patient to align the imaged eye optical axis 9i with the system optical axis 28.
  • This functionality can be implemented in several different ways.
  • the first focal point 146 can be fixed to lie on the system optical axis 28.
  • the image processor 120' can identify the lateral and angular misalignments of the imaged eye li by processing the image of the eye l i;
  • the image processor 120' can present or project the second fixation light 175' with a suitably located initial focal point 176, and
  • the image processor 120' can move or adjust the second fixation light 175' towards the system optical axis 28 to guide the patient 8 to align the imaged eye optical axis 9i with the system optical axis 28.
  • the adjustability of the second focal point 176 is indicated with a solid arrow.
  • the second fixation light 175' and its focal point 176 can be fixed on the system optical axis 28 and the first focal point 146 can be adjusted by the image processor 120' to guide the patient 8 to align the imaged eye optical axis 9i with the system optical axis 28.
  • the adjustability of the first fixation light 145' and its focal point 146 is indicated with a solid arrow.
  • FIG. 20A illustrates that in yet other implementations, both the first focal point 146 and the second focal point 176 can be adjustable, indicated by the two solid arrows.
  • the image processor 120' can carry out more complex or optimized guidance protocols to guide the patient 8 to align the imaged eye optical axis 9i with the system optical axis 28.
  • FIG. 20B illustrates yet other embodiments based on the above design principles.
  • the ophthalmic system 100 projects a collimated fixation light 145 to the eye.
  • the collimator 142 makes the rays of the fixation light 145 essentially parallel, the patient may not be able to see the collimated fixation light 145 from a typical misaligned initial position. In such systems, the patient 8 may not be able to follow instructions to align the imaged eye with the collimated fixation light 145 and may need assistance.
  • Some embodiments may assist the alignment process in these collimator implementations with providing the locator light 175', focused at the second focal point 176. Since the locator light 175' is not collimated, the patient 8 is able to see the second focal point 176 even from misaligned positions.
  • the image processor 120' can subsequently move or adjust the locator light 175' (shown by the solid arrow) to assist the patient to rotate and move the imaged eye until the patient sees the collimated fixation light 145'.
  • FIG. 21 illustrates that some ophthalmic systems 100" can also include a procedure laser 190.
  • the procedure laser 190 can be used to perform an ophthalmic surgical procedure after the high precision alignment and docking made possible by the misalignment reduction system 130.
  • the surgical procedure can include a cataract surgery, a refractive procedure, a retina-related procedure and a wide variety of other ophthalmic procedures.
  • Some of these ophthalmic systems 100" may also include a secondary imaging system 195.
  • This secondary imaging system 195 can include an optical coherence tomographic (OCT) system.
  • OCT systems especially the spectrometer based frequency-domain type, are well suited to image three dimensional ophthalmic target regions, as they are capable of acquiring image data from all depth of the target region simultaneously.
  • the beams of the procedure laser 190 and the secondary imaging system 195 can be coupled into the main optical pathway by beam splitters BS1 and BS2, respectively.
  • Such systems may combine the z-directional imaging functionality of the OCT imaging system 195 with the above described image processing-based alignment procedure to achieve alignment both with visible ophthalmic structures as well as with targets inside the eye.
  • FIG. 22 illustrates an operation of the above described ophthalmic systems 100-100'-100".
  • a method 200 of aligning an eye with the ophthalmic system 100-100'- 100" can include the following phases, (a) A generating of an image 210 that generates an image of a portion of the imaged eye li of a patient by the ophthalmic imaging device 100-100'-100".
  • the generating an image 210 can include generating an image 212 of a portion of the imaged eye 1 i with the imaging device 1 10-1 1 0'- l 10".
  • the determining the misalignment 220 can include (1) identifying an ophthalmic structure 222 in the image 212.
  • the ophthalmic structure can be the pupil 4, the lens 5, and the limbus 6, among others.
  • the determining 220 can also include (2) determining the misalignment by determining a location of the ophthalmic structure 222 relative to a reference of the imaging device by the image processor 120.
  • the reference of the imaging device can be the objective 1 12, a patient module, a docking tip, an interface, a contact lens, a pupil, a viewing frame, a reference frame, an internal lens of the ophthalmic system, or a reference pattern 1 17 generated by the imaging device 1 10-1 10'- 1 10".
  • the misalignment can be a lateral or an angular misalignment, determined by the image processor 120 by analyzing the image using software implementations.
  • the image processor 120 can generate a control signal according to the determined misalignment and output the generated control signal to the misalignment-reduction system 130.
  • the generating the misalignment-reduction response 230 can include generating the misalignment-reduction response 230 by the misalignment reduction system 130.
  • the generating the misalignment-reduction response 230 can include generating the fixation light 145 by the fixation light source 140 according to the misalignment determined by the image processor 120, in response to the control signal from the image processor 120.
  • the fixation light 145 can guide the patient 8 to reduce an angular or a lateral misalignment.
  • the fixation light source 140 may include a collimator 142 to generate the fixation light 145 to guide the patient 8 to reduce a lateral
  • the fixation light 145 can be generated for the non-imaged, or control eye lc, and the fixation light 145 can be adjusted according to the determined misalignment to assist the patient to reduce the misalignment. In other implementations, the fixation light 145 can be generated for the imaged eye li.
  • the generating the misalignment-reduction response 230 can include the gantry controller 150 moving the gantry 155 of the imaging device 1 10 to reduce a lateral misalignment.
  • the gantry controller 150 can move the bed 168, or a combination of the bed 168 and the gantry 155.
  • the determining the misalignment 220 can include determining an angular and a lateral misalignment by the image processor 120 processing the image and an additional misalignment information.
  • the generating the misalignment- reduction response 230 can include operating the fixation light system 140 and the gantry controller 150 to reduce the angular and the lateral misalignment.
  • the determining the misalignment 220 can include (1) projecting the locator light 175 onto the imaged eye li by the locator light source 170, (2) locating an image 177 i of the apical reflected locator light 177 in the image generated by the imaging device 1 10, and (3) determining the misalignment information using the located imaged apical reflected locator light 177i.
  • the determining the misalignment information 220 can include determining an angular misalignment information, related to a distance or vector between the image of the apical reflected locator light 177i and a location of an imaged ophthalmic structure; and determining a lateral misalignment information, related to a distance or vector between the imaged apical reflected locator light 177i or the location of the imaged ophthalmic structure and a reference of the imaging system.
  • the generating the misalignment-reduction response 230 can include reducing the angular misalignment by adjusting the fixation light system 140 and reducing the lateral misalignment by operating the gantry controller 150. As the first phase of reducing the misalignment may only reduce the misalignment but not eliminate it, the reducing the angular misalignment and the reducing the lateral misalignment phases can be repeated iteratively and alternately in some implementations.
  • the generating the misalignment-reduction response 230 can include using the locator light as a second fixation light 175'.
  • the reducing the lateral and the angular misalignment can include instructing the patient 8 to align the first fixation light 145' and the locator/second fixation light 175'.
  • some implementations of the ophthalmic imaging system may include an imaging device that generates an image of an imaged eye of the patient and a processor that determines a misalignment of the imaged eye and the imaging device by processing the generated image.
  • the processor can control a fixation light system to project a fixation light on an eye of the patient to reduce an angular misalignment, and control a gantry to adjust a movable optical element of the system to reduce a lateral misalignment.
  • Some implementation of the ophthalmic imaging system can include an indicator light system that projects an indicator light on the imaged eye to provide misalignment information for the processor.

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Abstract

An ophthalmic system is provided that includes an ophthalmic imaging device to generate an image of a portion of an imaged eye of a patient, an image processor to determine a misalignment of the imaged eye and the imaging device by processing the generated image, and to generate a control signal according to the determined misalignment, and a misalignment-reduction system to receive the control signal, and to generate a misalignment-reduction response. The misalignment-reduction system can include a fixation light system or a gantry. In some cases a locator light system may provide additional alignment information for the image processor.

Description

IMAGE-PROCESSOR-CONTROLLED MISALIGNMENT-REDUCTION FOR
OPHTHALMIC SYSTEMS
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority under 35 U.S.C. § 1 19 to U.S. Patent Application Serial No. 13/098,586, filed May 2, 201 1 , the entire contents of which are incorporated herein by reference.
TECHNICAL FIELD
(0002] This patent document relates to systems and techniques for ophthalmic imaging. In more detail, this patent document relates to systems and methods for providing an electronically controlled fixation light for improving a precision of aligning or docking an ophthalmic imaging system to a patient's eye.
BACKGROUND
[0003] A variety of advanced imaging devices have been developed over the years for ophthalmic imaging, diagnostics and surgery. For some applications, these imaging devices perform best when their optical axis is aligned with an optical axis of the imaged eye. Once the optical axis of the eye is aligned with the optical axis of the imaging device, some imaging devices enhance the precision of the imaging process by immobilizing the eye in the aligned position with the help of a patient interface or eye-docking system. As the precision of the imaging devices improves, the demand for eye-docking systems which provide more precise alignment also increases.
[0004] In typical existing systems the alignment is guided manually. The operator can direct the patient verbally, manually orient the eyeball, or adjust portions of the imaging device, such as its objective or gantry, or any combination of the above. These
adjustments are performed iteratively during the docking process. However, the inaccuracy of these manual approaches can make the docking process quite time consuming and frustrating, and still fall short of achieving high quality alignment.
Because of the limited precision of the manually guided alignment, the patient interface often ends up docked to the eye in an ofl-center position, the eye's optical axis tilted and the eye laterally misplaced relative to that of the imaging system.
[0005] Some imaging systems use guidance mechanisms that promise improvements for the alignment process. In some systems, such as in some surgical systems using excimer lasers, the alignment is aided by a fixation light. The fixation light can be centered with the optical axis of the imaging system. The patient can be instructed to train his eye on the fixation light. This fixation can align the patient's eye with the imaging system. However, even these fixation light systems have limitations.
SUMMARY
[0006] This patent document discloses fixation light controller systems with improved functionalities. The eye of the patients typically has both lateral and angular misalignment relative to the imaging system. Simply looking at a fixed fixation light centered with the optical axis of the imaging device does not eliminate both types of misalignments.
[0007] Therefore, in some systems, including some YAG lasers and slit lamps, the fixation light is not fixed and can be manually or mechanically adjusted. However, since the adjustment is only mechanical/manual, the precision of these fixation lights is considerably less than the precision of the imaging systems. Further, such mechanical adjustments can be quite time consuming and frustrating because of their limited precision.
[0008] Finally, in some systems the fixation light may be controlled in part manually and in part electronically. In the hands of expert surgeons manual operations may improve the alignment, in other cases such system may still lack the required precision.
[0009] The present patent document discloses fixation light controller systems that offer solutions for the above described problems. In some implementations, an
ophthalmic system may include an ophthalmic imaging device configured to generate an image of a portion of an imaged eye of a patient, an image processor, configured to determine a misalignment of the imaged eye and the imaging device by processing the generated image, and to generate a control signal according to the determined
misalignment, and a misalignment-reduction system, configured to receive the control signal, and to generate a misalignment-reduction response.
[0010] In some implementations the ophthalmic imaging device can include an electronic sensing system that senses a collected imaging light from the imaged eye, including at least one of a Charge-Coupled Device (CCD) array, a Complementary Metal- Oxide Semiconductor (CMOS) array, a pixel-array, and an electronic sensor array, and an electronic display system that displays the image of a portion of the imaged eye in relation to the sensed collected imaging light, including at least one of a Light Emitting Diode (LED) display, a plasma screen, an electronic display, a computer display, a Liquid Crystal Display (LCD) screen, a Cathode Ray Tube (CRT) display, a video-module, a video microscope display, a stereo video microscope display, a high definition (HD) video microscope, a processor-based image system, an opto-mechanical projector of the electronic or digital type, and a light-source movable by an electro-mechanical actuator.
[0011] In some implementations the image processor is configured to identify an ophthalmic structure in the image, and to determine a measure of misalignment by determining a location of the ophthalmic structure relative to a reference of the imaging device. In some implementations the image processor is configured to identify the ophthalmic structure by determining a high-gradient line in the image, separating image elements with substantially different brightness or color.
[0012] In some implementations the image processor is configured to fit at least one of a circle and an ellipse to the high-gradient line by measuring radial distances between the high-gradient line and the circle or ellipse, to determine a location coordinate of the fitted circle or ellipse by minimizing a measure of the radial distances, and to determine a misalignment-measure by relating the determined location coordinate and a coordinate of the reference. In some implementations the image processor is configured to determine a high-contrast line in the image, to determine misalignment distances between the high- contrast line and a targeting pattern, and to determine a misalignment-measure from the misalignment distances.
[0013] In some implementations the reference of the imaging device is at least one of an objective, a patient module, a docking tip, an interface, a contact lens, a pupil, a viewing frame, a reference frame, and an internal lens of the ophthalmic system, and the imaging device is configured to generate a reference pattern related to the reference to assist the image processor to determine the misalignment of the imaged eye and the imaging device. In some implementations the recognized ophthalmic structure is a limbus of the imaged eye. In some implementations at least a portion of the image processed by the image processor is not displayed by the imaging device.
[0014] In some implementations the misalignment-reduction system can include a fixation light source, and the misalignment-reduction response comprises the fixation light source generating a fixation light in response to the received control signal. In some implementations the fixation light source is configured to generate the fixation light for a non-imaged eye of the patient, and to move the generated fixation light according to the received control signal to assist a reduction of a misalignment between the imaged eye and a reference-component of the ophthalmic system. In some implementations the fixation light source can include at least one of a LED array, a plasma screen, an electronic display, a computer display, an LCD screen, a video-module, an opto-mechanical projector of the electronic or digital type, a CRT display, a slit-lamp, a processor-based image system, and a light-source movable by an electro-mechanical actuator. In some implementations the fixation light source is configured to generate the fixation light to guide the patient to reduce an angular misalignment.
[0015] In some implementations the image processor is configured to determine the angular misalignment by fitting an ellipse to a high-contrast line of the image, and analyzing at least one of an aspect ratio and an area of the fitted ellipse. In some implementations the fixation light source can include a collimator to generate a fixation light to guide the patient to reduce a lateral misalignment.
[0016] In some implementations the misalignment-reduction system can include a gantry, configured to move a movable portion of the imaging device, and a gantry controller, configured to receive the control signal from the image processor, and to move the gantry according to the received control signal, and the misalignment-reduction response can include the gantry controller moving the gantry and thus the movable portion of the imaging device to reduce a lateral misalignment. In some implementations the gantry is also part of the ophthalmic imaging device. In some implementations the misalignment-reduction system can include a support-gantry, configured to move a patient support relative to the imaging device, and a gantry controller, configured to receive the control signal from the image processor, and to move the support-gantry according to the received control signal, and the misalignment-reduction response can include the gantry controller moving the support-gantry and thus the patient support to reduce a lateral misalignment.
[0017] In some implementations the image processor is configured to determine an angular and a lateral misalignment by processing the image, and the misalignment- reduction system can include only one of a fixation light source and a gantry controller.
[0018] In some implementations the image processor is configured to determine an angular and a lateral misalignment by processing the image, and the misalignment- reduction system can include a fixation light source, a gantry and a gantry controller. In some implementations, the image processor is configured to determine an angular and a lateral misalignment by processing the image and a misalignment information.
[0019] In some implementations the imaging system can include a locator light source, configured to project a locator light on the imaged eye, and the image processor is configured to identify an apical reflected locator light in the image generated by the imaging device, and to determine the misalignment information by analyzing the apical reflected locator light. In some implementations the misalignment information is at least one of an angular misalignment information, related to a vector in the image between the apical reflected locator light and a location of an imaged ophthalmic structure, and a lateral misalignment information, related to a vector in the image between a reference of the imaging system and at least one of the apical reflected locator light and the location of an imaged ophthalmic structure.
[0020] In some implementations the ophthalmic system is configured to reduce the angular misalignment by adjusting the fixation light source, and to reduce the lateral misalignment by operating the gantry controller. In some implementations the fixation light is adjustable so that the locator light and a location of an imaged ophthalmic structure can be aligned by adjusting the fixation light. In some implementations the fixation light source and the locator light source are capable of operating at different wavelengths. In some implementations the locator light is invisible for the imaged eye.
[0021] In some implementations a patient interface is configured to dock to the imaged eye of the patient after the misalignment-reduction system executed the
misalignment-reduction response. In some implementations the misalignment-reduction system can include a fixation light source, configured to generate a fixation light for the imaged eye of the patient, and to adjust the generated fixation light according to the received control signal to assist a reduction of a misalignment between the imaged eye and a reference-component of the ophthalmic system. Some implementations include a locator light, focusable to a second focal point different from a first focal point of the fixation light.
[0022] In some implementations a method of aligning an eye with an ophthalmic system can include generating an image of a portion of an imaged eye of a patient by an ophthalmic imaging device, determining a misalignment of the imaged eye and the imaging device by an image processor processing the generated image, and generating a misalignment-reduction response electronically by a misalignment-reduction system based on the determined misalignment.
[0023] In some implementations the determining the misalignment can include identifying an ophthalmic structure in the image, and determining a location of the ophthalmic structure relative to a reference of the imaging device. In some
implementations the generating the misalignment-reduction response can include generating a fixation light by a fixation light source according to the determined misalignment.
[0024] In some implementations the generating the fixation light can include generating the fixation light to guide the patient to reduce an angular misalignment. In some implementations the generating the fixation light can include generating a fixation light to guide the patient to reduce a lateral misalignment, wherein the fixation light source can include a collimator.
[0025] In some implementations the generating the fixation light can include generating the fixation light for a non-imaged eye of the patient, and the generating the misalignment-reduction response can include adjusting the fixation light according to the determined misalignment to assist the patient to reduce the misalignment. In some implementations the generating the fixation light can include generating the fixation light for the imaged eye of the patient, and the generating the misalignment-reduction response can include adjusting the fixation light according to the determined misalignment to assist the patient to reduce the misalignment.
[0026] In some implementations the generating the misalignment-reduction response can include moving a gantry of the imaging system by a gantry controller to reduce a lateral misalignment.
[0027] In some implementations the determining the misalignment can include determining an angular and a lateral misalignment by the image processor processing the image and a misalignment information, and the generating the misalignment-reduction response can include adjusting a fixation light of a fixation light system and a gantry controller. In some implementations the determining the misalignment can include projecting a locator light onto the imaged eye by a locator light system, locating an apical reflected locator light in the image generated by the imaging device, and determining the misalignment information using the located apical reflected locator light. In some implementations the determining the misalignment information can include determining an angular misalignment information, related to a vector in the image between the apical reflected locator light and a location of an imaged ophthalmic structure, and determining a lateral misalignment information, related to a vector in the image between a reference of the imaging system and at least one of the apical reflected locator light and the imaged ophthalmic structure.
[0028] In some implementations the generating the misalignment-reduction response can include reducing the angular misalignment by adjusting the fixation light, and reducing the lateral misalignment by operating the gantry controller. In some
implementations the reducing the angular misalignment and the reducing the lateral misalignment are repeated iteratively. In some implementations the generating the misalignment-reduction response can include projecting the fixation light into the imaged eye, and reducing the lateral and the angular misalignment by causing the head of the patient to move laterally to align the locator light and the fixation light.
[0029] In some implementations an ophthalmic system can include an imaging device that generates an image of an imaged eye of a patient, an image processor that determines an angular and a lateral misalignment of the imaged eye and the imaging device by processing the generated image, a fixation light system that projects a fixation light on an eye of the patient to assist a reduction of the angular misalignment, and a gantry that adjusts a movable optic of the system to reduce the lateral misalignment. In some implementations the ophthalmic system can include an indicator light system that projects an indicator light on the imaged eye to provide a misalignment information for the image processor. BRIEF DESCRIPTION OF THE DRAWINGS
[0030] FIG. 1 illustrates an eye.
[0031] FIG. 2 illustrates an ophthalmic imaging system.
[0032] FIGS. 3A-C illustrate misalignments of the eye.
[0033] FIG. 4 illustrates an ophthalmic system with a misalignment reduction system.
[0034] FIGS. 5A-E illustrate an image processing system.
[0035] FIGS. 6A-B illustrate a fixation light system.
[0036] FIGS. 7A-C illustrate a misalignment reduction method.
[0037] FIGS. 8A-B illustrate misalignment reduction with a fixation light.
[0038] FIGS. 9A-B illustrates an image processing method to determine an angular misalignment.
[0039] FIGS. 10A-B illustrate a collimated fixation light system.
[0040] FIG. 11 illustrates a misalignment reduction system with a gantry.
[0041] FIGS. 12A-B illustrate an operation of the gantry system.
[0042] FIG. 13 illustrates a bed gantry system.
[0043] FIG. 14 illustrates a system combining a fixation light and a gantry.
[0044] FIGS. 15A-B illustrate an operation of the fixation light-and-gantry system.
[0045] FIGS. 16A-B illustrate a system with a locator light.
[0046] FIGS. 17A-B illustrate a locator light system processing an angular and a lateral misalignment.
[0047] FIG. 18 illustrates the reduction of the lateral and angular misalignment.
[0048] FIGS. 19A-B illustrate a fixation light system, projecting the fixation light into the imaged eye of the patient. [0049] FIGS. 20A-B illustrate a system with two fixation lights.
[0050] FIG. 21 illustrates a system with an additional OCT imaging system.
[0051 ] FIG. 22 illustrates a method of operating the ophthalmic system with the misalignment reduction system.
DETAILED DESCRIPTION
[0052] Implementations and embodiments in this patent document provide a fixation light system for ophthalmic imaging devices for increasing the precision of the alignment of the imaged eye and the imaging device.
|0053] FIG. 1 illustrates a human eye 1 in some detail. The eye 1 includes a cornea 2 that receives and refracts the incoming light, an iris 3, a pupil 4, in effect an opening for the light to enter the inner eye, and a lens 5 that focuses the light on the retina. In addition, the eye 1 includes a limbus 6, delineating the boundary between the colored iris 3 and a white sclera 7.
[0054] FIG. 2 illustrates an ophthalmic imaging system 10 and its operation. A patient 8 can be laid on a supporting bed. An imaging light source 1 1 can shine an imaging light on an imaged eye l i. A portion of the imaging light reflected by the imaged eye l i can be collected by an objective 12 and guided as a collected imaging light 13 to an optic or optical system 14. The optic 14 can guide the collected imaging light 13 to an imaging module 15. A surgeon or medical professional can analyze the image provided by the imaging module 15 and give instructions to the patient to move the imaged eye 1 i to improve its alignment with an optical axis of the imaging system 10. In other cases, the surgeon can manipulate the imaged eye li manually to improve the alignment. These steps can be practiced to prepare the imaged eye 1 i for docking a patient interface to it, or just simply to align the eye with the imaging system 10 better. The patient interfaces can be used either to assist the imaging the eye li, or for performing an ophthalmic surgical procedure. In other systems, a non-contact imaging procedure can be performed after the alignment. In yet other systems, the alignment can be followed by a diagnostic procedure. In any of the above described systems the ophthalmic imaging system 10 provides the surgeon only with an image of limited precision as the alignment with the eye is only approximate.
[0055] FIGS. 3A-B illustrate that after the use of such a limited precision ophthalmic imaging system 10, a residual misalignment between the eye 1 and the ophthalmic imaging system 10 can persist. In detail, a distal end 20 of the ophthalmic system 10 can be the objective 12, or a contact module, a docking unit, a distal tip, an interface, or an applanation module. In any of these designs, the distal end 20 can include a housing 21 that supports a distal lens 22. An optical axis 28 of the ophthalmic imaging system 10, typically shared with an optical axis of the distal lens 22, can remain misaligned with an optical axis 9 of the eye 1 even after the above limited-precision docking procedure has been performed.
[0056] FIG. 3A illustrates that the misalignment can be a lateral misalignment characterized by a (Δχ, Δγ) vector between the optical axis 9 of the eye and the optical axis 28 of the imaging system 10, lying approximately in the lateral plane perpendicular to the optical axis 28.
[0057] FIG. 3B illustrates that the misalignment can also be an angular misalignment. In general, the angular misalignment can be characterized by the (θ,φ) Euler angles between the optical axis 9 of the eye and the optical axis 28 of the imaging system 10. In many cases, the misalignment can be a combination of a lateral and an angular
misalignment.
[0058] FIG. 3C illustrates that on an imaging interface of the imaging module 15 either misalignment can appear as a displacement of the iris 3 and pupil 4 relative to a targeting pattern 17, such as a target circle. The surgeon can give verbal instructions to the patient to move the imaged eye 1 i, or to manipulate the eye 1 i manually based on this displayed displacement.
[0059] However, verbal instructions can be unclear to an already disoriented patient, and manipulating the eye can be cumbersome and imprecise. Also, the patient is likely to undo or resist the actions of the surgeon or technician.
[0060] Some ophthalmic systems can utilize a fixation light to provide guidance for the patient. However, fixation light devices still have shortcomings as discussed above. Some devices provide adjustable fixation lights as an improvement. However, even in such systems, the location of the fixation light is typically adjusted manually or mechanically, still resulting in an adjustment process with limited precision.
[0061] FIG. 4 illustrates an ophthalmic imaging system 100 that can be used to align the imaged eye 1 i and the ophthalmic system 100 with improved precision. The ophthalmic system 100 can include an ophthalmic imaging device 1 10, an image processor 120 and a misalignment reduction system 130. The ophthalmic imaging device 1 10 can be configured to generate an image of a portion of an imaged eye of a patient. The image processor 120 can be configured to determine a misalignment of the imaged eye and the imaging device by processing the generated image, and to generate a control signal according to the determined misalignment. The misalignment-reduction system 130 can be configured to receive the control signal and to generate a misalignment-reduction response.
|0062] The ophthalmic imaging device 1 10 can include an imaging light source 1 1 1 that provides an imaging light for the imaged eye l i. The imaging light source 1 1 1 can be a single light, a ring of e.g. 4, 6 or 8 lights, or a light source with a continuous ring shape. An objective 1 12 can collect a fraction of the imaging light, returned by the imaged eye l i, and direct it as a collected imaging light 1 13 to an optic 1 14. The optic 1 14 can guide the collected imaging light 1 13 towards an imaging module 1 15. In general, the optic 1 14 can be quite complex, including a large number of lenses and mirrors. The optic 1 14 can also be multifunctional, for example also configured to guide a surgical laser beam to the imaged eye li. The imaging module 1 15 can provide an image for an operator of the imaging system 100 via an imaging interface.
[0063] In some implementations, the ophthalmic imaging device 1 10 can include a microscope, an ophthalmic microscope, or a stereo microscope. An imaging interface of these microscopes can include the eyepiece of these microscopes.
[0064] In some implementations, the ophthalmic imaging device 1 10 can generate the image at least in part electronically. For example, the imaging module 1 15 of the ophthalmic imaging device 1 10 can include an electronic sensing system that senses the collected imaging light 1 13. The electronic sensing system can include a Charge-Coupled Device (CCD)-array, a Complementary Metal Oxide Semiconductor (CMOS) array, a pixel-array, or an electronic sensor array to sense the collected imaging light 1 13.
[0065] In these electronic imaging systems the imaging module 1 15 can also include an electronic display system as an imaging interface. This electronic display can display an electronic image of a portion of the imaged eye li based on the sensed light 1 13. This electronic display or imaging interface can be, for example, a Light Emitting Diode (LED), an organic LED (OLED) display, an active matrix OLED (AMOLED) display, a plasma screen, an electronic display, a computer display, a Liquid Crystal Display (LCD) screen, a Cathode Ray Tube (CRT) display, a video-module, a video microscope display, a stereo video microscope display, a High Definition (HD) video microscope, a processor- based image system, an opto-mechanical projector of the electronic or digital type, or a light-source movable by an electro-mechanical actuator. In some implementations, the above elements of the imaging systems can be combined.
[0066] In some implementations, the ophthalmic imaging device 1 10 can include an optical coherence tomographic (OCT) imaging system, as described in relation to FIG. 21.
[0067] In some implementations, the misalignment reduction system 130 may include the objective 1 12, in others portions of the optic 1 14.
[0068] The image processor 120 can be configured to identify an ophthalmic structure in the image, generated by the imaging device 1 10, and to determine a location of the ophthalmic structure relative to a reference of the imaging device. The reference of the imaging device can be the objective 1 12, a patient module, a docking tip, an interface, a contact lens, a pupil, a viewing frame, a reference frame, and an internal lens of the ophthalmic system. The imaging module 1 15 can be configured to generate a reference pattern related to the reference to assist the image processor to determine the misalignment of the imaged eye and the imaging device. A targeting circle similar to the targeting pattern 17 can be such a reference pattern. Other reference patterns may include cross hairs, multiple circles and their combinations.
[0069] The image processor 120 may be configured to recognize the limbus 6 as the ophthalmic structure. The image processing may be based on the pupil 4 as well, but often the limbus 6 forms a more regular circle and thus is well suited for the image processing.
[0070] FIGS. 5A-E illustrate that in operation, the image processor 120 can first identify one or more ophthalmic structures of the imaged eye l i e.g. by analyzing the contrast or gradient of the nearby pixels of the image.
[0071] FIG. 5A illustrates that the image processor 120 may perform a radial scan of the image and record the pixels' brightness, color or both along the scan. The center of the radial scan can be chosen in different ways. Also, non-radial scans, such as circular, linear, rectangular, mesh-type, 2D and many other types of scans can be used. [0072] Next, the image processor 120 can identify a high-gradient or high-contrast pixel 121 along the scan as the pixel where the recorded brightness or color varies the fastest. A high-contrast or high-gradient line 122 can be defined by connecting the high- gradient/contrast pixels of nearby scans. Such a high-gradient/contrast line can separate ophthalmic regions with strongly differing brightness or color and thus can be a useful indicator of ophthalmic structures, such as the limbus 6 or the pupil 4. Numerous other methods of machine-vision and image processing are known in the arts to determine structures and their boundaries, which can be used in place of the above described high- gradient/contrast method.
[0073] FIG. 5B illustrates that subsequently the image processor 120 can fit probe- functions, such as fitting circles 124 or ellipses to the identified high-gradient/contrast lines to identify circular ophthalmic structures, such as the limbus 6 or the pupil 4. The fitting can take several forms. In some cases, the center and radius of the fitting circle 124 can be moved so that the fitting circle overlays the high-gradient/contrast line with the highest precision. The precision can be quantified e.g. by defining a magnitude of the average radial distance Δ as the square-root of the average of the squared radial distances between the fitting circle 124 and the high-gradient/contrast line 122 along a preset number of rays, such as 4, 6, or 8 rays. This magnitude of the average radial distance Δ can be varied by moving around the coordinates (Cx,Cy) of the center of the fitting circle 124 controlled by a search algorithm. Here, the (x,y) coordinate system can be affixed e.g. to the reference system of the interface of the imaging module 1 15. FIG. 5B illustrates a 4-ray implementation, where the average radial distance is defined as
Δ = [(Δ12+Δ22+Δ32+Δ42)/4]Ι/2
[0074] FIG. 5C illustrates that when the search algorithm reaches a minimum of the average radial distance Δ by shifting the coordinates (Cx,Cy) of the center of the fitting circle 124', the shifted fitting circle 124' becomes essentially concentric with the ophthalmic structure, defined by the high-gradient/contrast line 122. This can be seen e.g. from the symmetry of the individual radial distances: Δ1 = Δ2 = Δ3 = Δ4.
Correspondingly, the center coordinates (Cx,Cy) of the shifted fitting circle 124' essentially coincide with the coordinates (Ox,Oy) of the center of the ophthalmic structure, corresponding to the high-gradient/contrast line 122. This approach can be terminated when the shifted fitting circle 124' becomes concentric with the ophthalmic structure 122, but the radii of the two structures remain different.
[0075] FIGS. 5D-E illustrate that some implementations can also determine the radius of the ophthalmic structure by continuing the search after the concentric state is reached by adjusting the radius of the shifted fitting circle 124' until the global minimum A(min) is found. For precisely circular structures it may be possible to reach the A(min)=0 absolute global minimum. Once the global minimum A(min) is reached, the radius of the radius- adjusted fitting circle 124" is essentially equal to the radius of the ophthalmic structure, such as the limbus 6.
[0076] In a typical case, the image processor 120 may be able to fit a fitting circle 124 to the high-gradient/contrast line 122 with or without adjusting its radius and thus conclude that the ophthalmic structure indicated by the high contract line 122 is circular. Next, the image processor 120 may determine that the color of the pixels changes from white to non-white across the high-gradient/contrast line 122. These findings can be sufficient for the image processor 120 to conclude that it identified the circular limbus 6 of the imaged eye l i.
[0077] During this fitting process the image processor 120 determines the coordinates of the center of the limbus 6, since the limbus 6 is concentric with the shifted fitting circle 124' and thus the center of the limbus 6 is located at the same (Cx,Cy) coordinates as the center of the shifted fitting circle 124'. Therefore, the image processor 120 can determine a misalignment vector 143 that connects the (Cx,Cy) coordinates of the center of the limbus 6 to the known center coordinates of a targeting pattern 1 17. The misalignment vector 143 may be used by a misalignment reduction system 130 to reduce the
misalignment of the imaged eye l i with the ophthalmic system 100 as described below.
[0078] FIGS. 6A-B illustrate an implementation of the ophthalmic imaging system 100 where the misalignment reduction system 130 includes a fixation light source 140. The fixation light source 140 can project a fixation light 145 into a non-imaged control eye l c of the patient 8. The patient 8 can be instructed to focus on or follow the fixation light 145 with the control eye l c. The misalignment reduction response of the misalignment reduction system 130 can be an adjustment of the fixation light 145. [0079] FIG. 7 A illustrates that the imaging module 1 15 can assist the determination of a misalignment of the imaged eye l i and a reference-component of the ophthalmic imaging device 1 10 by simultaneously displaying an image portion of the imaged eye l i and the reference or targeting pattern 1 17, such as a target circle, via its imaging interface.
[0080] The reference-component of the imaging device 1 10 can be the objective 1 12, a patient module, a docking tip, an interface, a contact lens, a pupil, a viewing frame, a reference frame, an internal lens of the ophthalmic system, or any equivalents.
[0081] The location or display of the targeting pattern 1 17 can be fixed to the reference-component, in effect indicating the position of the reference-component.
Therefore, the simultaneous display of the image portion of the imaged eye l i and the targeting pattern 1 17 by the imaging module 1 15 can effectively assist the determination of the misalignment of the imaged eye li.
[0082] The image processor 120 can analyze the simultaneously displayed image portion of the imaged eye l i and the target pattern 1 17 and compute the misalignment. The details of computing the misalignment were described above extensively. The image processor 120 can summarize the computed direction and magnitude of the misalignment by generating the misalignment vector 143. Based on this misalignment vector 143, the image processor 120 can compute a misalignment reduction vector 144 to be used by the misalignment reduction system 130 to reduce or eliminate the computed misalignment. In general, the misalignment reduction vector 144 need not be the same or simply opposite as the misalignment vector 143, as it represents how the misalignment reduction system is to be adjusted to reduce or eliminate the misalignment. As such, the misalignment reduction vector 144 also depends on the distance of the misalignment reduction system 130 from the eye 1 and on other factors and thus can refer to a large variety of misalignment reduction measures.
[0083] Next, the image processor 120 can generate a fixation light control signal for the fixation light source 140 according to the determined misalignment reduction vector 144.
[0084] In some implementations, the image of the eye portion and the targeting pattern 1 17 are not necessarily displayed. Rather, they can be provided for the image processor 120 by the imaging device 1 10 in an electronic form only, invisible for the system operator or surgeon.
[0085] Some image processors 120 do not utilize the fitting circle 124 of FIGS. 5B-E. Instead, these implementations can (a) directly determine misalignment distances Δ* 1 ... Δ*η between the high-contrast line 122 and the targeting pattern 1 17 along n rays, as described above, where n is an integer; and (b) perform a search algorithm to find a misalignment of the ophthalmic structure corresponding to the high-contrast line 122 relative to the targeting pattern 1 17 or another reference of the imaging system 100. A difference to the previously described method is that in the present method the targeting pattern 1 17 is centered to the imaging device 1 10, whereas in the previous systems in an intermediate step the fitting circles 124 were shifted to be concentric with the ophthalmic structure and then the misalignment of the fitting circle was determined relative to the targeting pattern 1 17.
[0086] The search algorithm can be based e.g. on minimizing a misalignment- measure, such as the average misalignment Δ above, or on symmetrizing the misalignment distances Δ* 1 . .. Δ*η in opposing directions, among others. After the search, the misalignment vector 143 can be determined to characterize the misalignment. The image processor 120 can then compute the misalignment reduction vector 144 based on the determined misalignment vector 143 and output a fixation light control signal towards the fixation light source 140 corresponding to the misalignment reduction vector 144.
[0087] FIG. 7B illustrates that the fixation light source 140 can receive the fixation light control signal and generate, project, or display a fixation light 145 according to the received fixation light control signal. For example, if the misalignment of the imaged eye l i was in the upper-left direction in the reference frame of the imaging system 1 10, as shown by the misalignment vector 143 in FIG. 7A, the image processor 120 can compute the misalignment reduction vector 144f by which the fixation light 145 is to be adjusted to the lower right direction so that if the control eye lc follows the adjusted fixation light 145, the misalignment 143 of the imaged eye l i will be substantially reduced, or optimally even eliminated.
[0088] The fixation light source 140 can first generate and display the fixation light 145, and then move the displayed fixation light 145 according to the received fixation light control signal. Since the movements of the control eye lc and the imaged eye li closely track each other, as the control eye lc is moved by the patient according to the displayed fixation light 145, the imaged eye li moves in a correlated manner. Because of this correlation between the movements of the imaged eye l i and the control eye lc, the fixation light system 120 can assist the reduction of the misalignment of the imaged eye l i relative to the ophthalmic imaging system 1 10.
[0089] Other embodiments may simply display the fixation light 145 by the fixation light source 140 at a properly chosen location according to the fixation light control signal, instead of moving it. In either of these embodiments, the patient can be instructed to follow, or focus on, the fixation light 145 with the control eye lc.
[0090] The fixation light source 140 can include a LED array, a plasma screen, an electronic display, a computer display, an LCD screen, a video-module, an optomechanical projector, a slit-lamp, a processor-based image system, or a light-source, movable by an electro-mechanical actuator.
[0091] FIG. 7C illustrates that after the patient followed the adjustment of the fixation light 145 with the control eye lc, the imaged eye l i can become essentially centered with the targeting pattern 1 17 and thus aligned with the optical axis 28 of the imaging system 100. Implementations may not adjust the radius of the targeting pattern 1 17 to fit the radius of the limbus 6, thus these circles may appear only concentric, but not overlaid.
[0092] FIG. 6B illustrates the appearance of the ophthalmic system 100 for the patient 8 in some embodiments. The left panel shows that the imaged eye l i can see the objective 1 12, surrounded by e.g. six imaging light sources 1 1 1. The right panel shows that the non- imaged/control eye l c can see the fixation light 145 displayed on the fixation light source 140. In this embodiment, the fixation light source 140 can be an LCD screen or an equivalent, and the fixation light 145 can be a bright spot displayed on the dark LCD screen 140.
[0093] To facilitate procedures on both eyes, some embodiments may include two fixation light sources 140, one on each side of the objective 1 12.
[0094] In some implementations, the image processor 120 may display the processed image e.g. for informing the medical technician or surgeon. In other implementations at least a portion of the image processed by the image processor 120 may not be displayed by the imaging system 100, only provided in electronic format to the image processor 120 by the imaging device 1 10.
[0095] FIGS. 8A-B illustrate the case when the eye's misalignment is purely angular, as was discussed in relation to FIG. 3B. As before, the optical axis 9i of the imaged eye l i may be rotated by the Euler angles (θ, ) relative to the optical axis 28 of the imaging system 100. Correspondingly, the optical axis 9c of the control eye l c may be rotated approximately by the same Euler angles (θ, φ) relative to the axis of the fixation light source 140, along which the fixation light 145 also propagates.
[0096] FIGS. 9A-B illustrate an operation of the image processor 120 configured to analyze the angular misalignment of FIGS. 8A-B. First, the image processor 120 can identify the various ophthalmic structures of the imaged eye li, such as the limbus 6i, by identifying the high-gradient/contrast lines 122 of the image, as described above.
[0097] FIG. 9A illustrates that while an aligned limbus 6ia would appear as a circle, in the case of angular misalignment the rotated limbus 6ir appears elliptical from the viewpoint of the image processor 120. Thus, in operation the image processor 120 will not be successful fitting a fitting circle 124 as a probe function to the high- gradient/contrast line 122.
[0098] FIG. 9B illustrates that once the image processor 120 is unsuccessful fitting a fitting circle 124 then it can attempt to fit a fitting ellipse 124' to the high-gradient/contrast line 122' to identify the rotated limbus 6ir or the rotated pupil 4ir. The aspect ratio a/c, i.e. the ratio of the length of the minor and major axes of the fitting ellipse 124', can be used to determine the Euler angles (θ, φ) of angular misalignment of the imaged eye l i.
[0099] FIG. 8B illustrates that once the image processor 120 was successful determining the Euler angles (θ, φ) of the angular misalignment from the aspect ratio a/c of the fitting ellipse 124' fitted to the high-gradient/contrast line 122', it can compute the misalignment reduction vector 144fa with which the fixation light 145 should be moved on the fixation light source 140. This misalignment reduction vector 144fa can be constructed so that if the control eye l c follows the fixation light 145 adjusted by the angular misalignment reduction vector 144fa, as indicated by the solid black arrow, the angular misalignment can be reduced, or possibly even eliminated. Here the f label of the misalignment reduction vector 144fa indicates that the misalignment reduction system 130 is of the fixation light 140 type, and the a label refers to an angular misalignment.
[00100] FIGS. 10A-B illustrate a case of a lateral misalignment Δ. The fixation light sources 140 can include a collimator 142 that can be configured to generate a fixation light 145 to guide the patient to reduce the lateral misalignment Δ efficiently. The collimator 142 can generate a fixation light 145 with essentially parallel rays, as if it had been generated by a light source at infinity. Thus, the patient 8 can see this collimated fixation light 145 only if he/she looks up straight along the line of the fixation light 145. Therefore, in systems where the collimated fixation light 145 is projected along the optical axis 28 of the system, when the patient manages to adjust the imaged eye to see the collimated fixation light 145, the optical axis 9i of the imaged eye is parallel to the system optical axis 28.
[00101] In operation, the image processor 120 can determine a lateral misalignment Δ of the imaged eye from the analysis of the image of the imaged eye l i, and compute a corresponding misalignment reduction vector 144fl, the label 1 referring to the lateral misalignment in this fixation light system, referred to by the label f. The image processor 120 then can generate a fixation light control signal representing the calculated
misalignment reduction vector 144fl to be sent to the fixation light source 140. Upon receiving the fixation light control signal, the fixation light source 140 can move or adjust the collimated fixation light 145 with the misalignment reduction vector 144fl, shown by the solid arrow. The patient 8 can be instructed to move his/her head to find the adjusted collimated fixation light 145. In order to actually see the collimated fixation light 145, the patient 8 will have to move his/her head laterally until the lateral misalignment Δ is essentially eliminated.
[00102] FIG. 11 illustrates an implementation of the misalignment-reduction system 130 that includes a gantry controller 150, configured to receive the fixation light control signal from the image processor 120 and to move a gantry 155 accordingly, wherein the gantry 155 is configured to move a movable portion of the imaging device 1 10. A motor or actuator, moving the gantry 155 can be part of either the gantry controller 150 or the gantry 155. The movable portion of the imaging device 1 10 can be the objective 1 12 or a portion of the optic 1 14. In this implementation the misalignment-reduction response includes the gantry controller 150 moving the gantry 155 to reduce a lateral misalignment. In some implementations the gantry 155 can be part of the ophthalmic imaging device 1 10.
[00103] FIGS. 12A-B illustrate an operation of the gantry-based system of FIG. 11. Often it is the case that the angular misalignment of the imaged eye l i is minimal, thus the primary purpose of the adjustment process is to reduce the lateral misalignment of the optical axis 9i relative to the optical axis 28 of the imaging device 1 10. This lateral misalignment, or displacement can be characterized by the misalignment vector 143 (Ax,Ay), or the magnitude of this misalignment vector 143, Δ, as discussed e.g. in relation to FIG. 3A.
[00104] FIG. 12A illustrates that the image processor 120 may analyze the image of the imaged eye l i, determine the misalignment vector (Ax,Ay), then determine the corresponding misalignment reduction vector 144gl, and output a control signal to the gantry controller 1 50 representing the misalignment reduction vector 144gl. Here the label g refers to the gantry type misalignment reduction system 130.
[00105] Some aspects of these gantry-based systems differ from those of the fixation light systems of FIGS. 6-10. In these gantry-based systems, the patient is not necessarily asked to move the imaged eye l i, as the gantry 155 is configured to move the movable portion of the imaging device 1 10 to reduce or eliminate the lateral misalignment.
[00106] FIG. 12B illustrates that the gantry controller 150 can, in response to the control signal, move the gantry 155 with the lateral misalignment reduction vector 144gl to eliminate the lateral misalignment Δ and align the optical axis 9i of the imaged eye with the optical axis 28 of the imaging device 1 10.
[00107] In practice, an ophthalmic surgeon often faces a combination of the above angular and lateral misalignments. Advanced single-component implementations of the misalignment-reduction system 130 may be able to reduce or eliminate both of these misalignments, as described next.
[00108] For example, in a misalignment-reduction system 130 with a fixation light source 140 component only, in a first phase the image processor 120 may follow the method of FIG. 9 to compute the angular misalignment of the imaged eye l i. However, the elliptic distortion of the limbus 6i can be caused both by the angular misalignment and by the lateral misalignment and these two effects need to be separated.
[00109] In an implementation the image processor 120 can project the fixation light 145 at a suitable first location and the patient can be instructed to focus on this once- adjusted fixation light 145. From measuring the ellipticity of the limbus 6i, the knowledge of first location and the location of the eye on the imaging interface 1 15, the image processor 120 can determine the lateral and angular misalignments. Based on the determined lateral misalignment, the patient can be instructed to move the imaged eye 1 i to the center of the imaging device 1 10. This process may be performed iteratively to reach sufficient precision. Sometimes the fixation light 145 can be readjusted and the ellipticity re-measured to assist the process.
[00110] After the eye is centered with sufficient precision, the image processor 120 may adjust the fixation light 145 for a second time, typically to a second location corresponding to the center of the imaging device 1 10. The patient 8 focusing on this twice adjusted fixation light 145 can eliminate the angular misalignment as well.
[00111 ] The apparent ellipticity of the limbus 6i may have a third cause as well besides the two types of misalignments: often the limbus 6i itself is not entirely circular. In some implementations, the image processor 120 may need to perform an advanced image processing algorithm to separate the three causes of the ellipticity. The advanced image processing may include tracking suitably chosen merit functions or the analysis of optical distortions of the image. An example of the merit function can be the area of the fitted ellipse.
[00112] Similarly, the single-component gantry-based misalignment-reduction system 130 may be able to correct both types of misalignments in separate phases as well.
[00113] If the above described two-phase methods only reduced the two
misalignments but did not eliminate them, the two phases can be repeated iteratively to substantially eliminate the two types of misalignments. A large variety of optimization and other search algorithms can be used to facilitate such iterative approaches.
[00114] FIG. 13 illustrates an implementation of the misalignment-reduction system 130 that includes a movable patient support, such as a bed 168, moved by a support/bed gantry 165 that is controlled and moved by a bed gantry controller 160. Upon receiving the control signal from the image processor 120, the gantry controller 160 can move the support/bed gantry 165 by a lateral misalignment reduction vector 144bl, which in turn moves the patient support/bed 168. Here the b label stands for the bed 168.
[00115] Aspects of this implementation include that the relative position of the optical elements in the imaging device 1 10 are not changed during regular operations, thus a high level of alignment and precision of the optics can be maintained. At the same time, the weight and physical extent of the patient support 168 is much greater than that of the objective 1 12, thus the high precision adjustment of the patient support 168 has its own challenges.
[00116] FIG. 14 illustrates that some implementations of the misalignment reduction system 130 may contain both a fixation light system 140-145 and a gantry system 150- 155. Such an integrated misalignment reduction system 130 may allow the surgeon to reduce and eliminate both types of misalignments in an efficient manner.
[00117] FIGS. 15A-B illustrate that in some embodiments, the image processor 120 may be able to determine the lateral and angular misalignments by the above described methods and direct the fixation light source 140 and the gantry controller 150 to reduce the misalignments.
[00118] FIG. 15A illustrates a typical situation, where the imaged eye has both a lateral misalignment Δ or (Ax, Ay) and an angular misalignment (θ, ). To handle such situations, the image processor 120 can be configured to analyze the image and compute a lateral misalignment reduction vector 1441 and an angular misalignment reduction vector 144a. As before, there are a large number of different measures of the misalignment, which can be expressed in terms of angular, linear, percentage and other variables. The term "misalignment vector" can refer to any of these variables, measures and their combinations.
[00119] FIG. 15B illustrates that the patient can be instructed to follow the fixation light 145 that is adjusted by the angular misalignment reduction vector 144fa to eliminate the angular misalignment. Then the gantry controller 150 can adjust the gantry 1 55 with the lateral misalignment reduction vector 144gl to eliminate the lateral misalignment. Integrated embodiments with such a gantry 155 can reduce the lateral misalignment efficiently and with high precision as they do not rely on the patient moving the imaged eye laterally.
[00120] The two phases of alignment reduction can be performed in the opposite order or in alternating repeated phases. Referring to FIG. 13, the gantry can also be the support gantry 165, moving the patient support 168 instead of the objective 1 12 or the movable portion of the optic 1 14.
[00121] FIGS. 16A-B illustrate that in some integrated systems the image processor 120 may be configured to determine the angular and the lateral misalignment by processing the image and an additional misalignment information.
[00122] The misalignment information can be originated by a locator light source 170. The locator light source 170 can generate a locator light 175 which can be coupled into the main optical pathway by a beam splitter 171. The optic 1 14 and in particular the objective 1 12 can guide or project the locator light 175 onto the imaged eye li.
[00123] If the imaged eye l i can be approximated by a reflecting sphere, or at least a portion of a reflecting sphere, then standard geometric considerations reveal that the portion of the locator light 175 that reflects back into the objective 1 12 parallel to the optical axis 28 is the one that is reflected from the apex of the spherical eye 1. This reflected light will be referred to as an apical reflected locator light 177. The other rays are shown to reflect away from the system optical axis 28.
[00124] FIG. 16B illustrates that an image 177i of the apical reflected locator light 177 can be detected by the image processor 120 in the overall image generated by the imaging device 1 10 on the imaging module 1 15, as shown by the white spot.
[00125] For a spherical imaged eye li having a lateral misalignment Δ relative to the system optical axis 28, the white spot image of the apical reflected locator light 177i does not coincide with the system optical axis, indicated by the solid cross. It is noted though that the relative locations of the white spot and the black cross are independent from a possible angular misalignment of the image eye. Thus, for spherical eyes the vector connecting the imaged apical reflected locator light 177i with the cross-mark of the system optical axis 28 can provide the additional alignment information for the image processor 120 that enables it to determine the lateral misalignment independently from the angular misalignment.
[00126] FIGS. 17A-B illustrate that the imaged eye is more appropriately modeled as a primary sphere with a protruding secondary sphere, corresponding to the cornea 2.
Some implementations of the image processor 120 can be configured to determine the misalignment information by analyzing the imaged apical reflected locator light 177i on the basis of this more realistic model. For this analysis, the image processor 120 can use one or more fitting parameters, or the results of pre-procedure imaging measurements.
[00127] FIGS. 17A-B illustrate a generic case with simultaneous angular
misalignment {θ, φ) and lateral misalignment Δ. If the imaged eye l i has only the lateral misalignment Δ, then the image spot of the apical reflected locator light 177i coincides with the center of the limbus 6ic, indicated by a solid x in FIG. 17B. This limbus center 6ic is not directly detected, but can be computed e.g. by fitting the fitting circle 124 to the image of the limbus 6i.
[00128] Therefore, the vector or distance connecting the image spot of the apical reflected locator light 177i and the limbus center 6ic is an example of a dominantly or purely angular misalignment information that can be used by the image processor 120 to generate a misalignment reduction vector 144fa for the fixation light source 140 to correct this angular misalignment.
[00129] On the other hand, determining the lateral displacement Δ, e.g. between the system optical axis 28 and the center lx of the imaged eye l i, may be more challenging when the complex shape of the eye is taken into account than the procedure in FIGS. 16A- B. Therefore, in a first phase, an operator of the system 100 may adjust the fixation light 145 and instruct the patient to focus on the adjusted fixation light 145 until the limbus center 6ic and the image spot of the apical reflected locator light 177i overlap or coincide, thus eliminating the angular misalignment and aligning the system optical axis 28 with the imaged eye's optical axis 9i.
[00130] In a subsequent second phase, the distance or vector between the system optical axis 28, indicated by the solid cross, and the overlapping image spot of the apical reflected locator light 177i and the limbus center 6ic (solid x) can provide a lateral misalignment information. The image processor 120 may compute the lateral
misalignment reduction vector 144gl using this lateral misalignment information and send a corresponding control signal to the gantry controller 150. In response, the gantry controller 150 can adjust the gantry 155 with the lateral misalignment reduction vector 144gl.
[00131] Numerous equivalent implementations of the above principles can be practiced as well, for example performing the first and second phases in repeated iterative steps or in reverse order.
[00132] FIG. 18 illustrates that some implementations of the misalignment reduction system 130 are configured to reduce or even eliminate both the angular and lateral misalignments by the above operations. As shown, the lateral misalignment can be reduced by the movement of the imaged eye l i alone, or by the complementary lateral movement (Ax,Ay) of the imaged eye l i and (Ax',Ay') of the imaging device 1 10.
[00133] Once both types of misalignments have been reduced or eliminated by the misalignment-reduction system 130, the operator of the ophthalmic system 100 may lower a patient interface 180, configured to dock to the imaged eye l i of the patient. This patient interface 180 can immobilize the imaged eye l i to keep it fixed for subsequent procedures. These procedures may include diagnostic procedures, imaging procedures and ophthalmic surgical procedures.
[00134] In detail, the objective 1 12 of the ophthalmic system 100 can include a distal objective lens 1 12- 1 , contained in an objective housing 1 12-2. The patient interface 180 can include an interface lens, contact lens, sometimes also called applanation plate 180-1 , contained in an interface housing 1 80-2. The patient interface 1 80 may be attached to the objective 1 12 or to the distal end of the imaging system 1 10. In other embodiments, part of the patient interface 1 80 can be attachable to the eye and the other part to the distal end of the imaging system 1 10. The patient interface 180 can be attachable to the eye with a suction ring or vacuum skirt 180-3.
[00135] In these architectures, the patient interface 180 can be docked with the imaged eye l i after the alignment of the imaged eye l i with the imaging device 1 10 has been completed. In other embodiments, the patient interface 180 can be docked with the imaged eye 1 i in an iterative manner. First, the imaged eye 1 i can be brought into alignment with the imaging device 1 10. Second, the patient interface can be lowered onto the imaged eye l i to make contact, but still allowing the imaged eye l i some movement. But since during the first phase the imaged eye 1 i may have moved, or the image processor 120 may not have determined the alignment perfectly, in a third phase the alignment procedure can be repeated and one or more new misalignment reduction vectors can be computed by the image processor 120. Fourth, the imaged eye li can be realigned using the newly computed misalignment reduction vector(s). These partial or stepwise phases can be followed by the full strength docking of the patient interface 180 onto the imaged eye l i, preventing further relative movement of the imaging device 1 10 and the imaged eye li.
[00136] FIGS. 19A-B illustrate that in some embodiments of the ophthalmic system 100', the fixation light source 140' can project the fixation light 145' not onto the control eye lc, but into the main optical pathway of the imaging device 1 10' with a beam splitter BS, so that the fixation light 145' is projected onto the imaged eye l i instead.
[00137] FIG. 19B illustrates the appearance of the embodiment 100' for the patient: the fixation light 145' appearing in the objective 1 12' itself, instead of a separate fixation light source 140' . In these embodiments, the patient may be instructed to follow the fixation light by the imaged eye li instead of the control eye lc. The other elements of these embodiments 100' as well as the principles of their operation can be analogous or equivalent to the above described systems.
[00138] FIGS. 20A-B illustrate variations of the embodiment 100' of FIGS. 19A-B.
In these embodiments, the locator light 175' can be used as a second fixation light. For example, the locator/second fixation light 175' can be focused to a second focal point 176, located at a z-coordinate z2 different from the z-coordinate zl of the first focal point 146 of the first fixation light 145'. Here the z-coordinates of the fixation lights can be measured from a zO reference level along the optical pathway. The z-coordinate zl of the first focal point 146 of the first fixation light 145' need not be at the distal end of the objective 1 12 as shown. The patient 8 can be instructed to move and rotate the imaged eye l i to align the first fixation light 145' and the second fixation light 175', in effect to align the first focal point 146 and the second focal point 176. If the first and second focal points 146 and 176 both lie on the system optical axis 28, this procedure guides the patient to align the imaged eye optical axis 9i with the system optical axis 28. This functionality can be implemented in several different ways.
[00139] In some cases the first focal point 146 can be fixed to lie on the system optical axis 28. In these implementations, (i) the image processor 120' can identify the lateral and angular misalignments of the imaged eye li by processing the image of the eye l i; (ii) the image processor 120' can present or project the second fixation light 175' with a suitably located initial focal point 176, and (iii) the image processor 120' can move or adjust the second fixation light 175' towards the system optical axis 28 to guide the patient 8 to align the imaged eye optical axis 9i with the system optical axis 28. In FIG. 20A the adjustability of the second focal point 176 is indicated with a solid arrow.
[00140] In another implementation, the second fixation light 175' and its focal point 176 can be fixed on the system optical axis 28 and the first focal point 146 can be adjusted by the image processor 120' to guide the patient 8 to align the imaged eye optical axis 9i with the system optical axis 28. In FIG. 20A the adjustability of the first fixation light 145' and its focal point 146 is indicated with a solid arrow.
[00141] FIG. 20A illustrates that in yet other implementations, both the first focal point 146 and the second focal point 176 can be adjustable, indicated by the two solid arrows. In these implementations the image processor 120' can carry out more complex or optimized guidance protocols to guide the patient 8 to align the imaged eye optical axis 9i with the system optical axis 28.
[00142] FIG. 20B illustrates yet other embodiments based on the above design principles. In the collimator implementation of FIGS. 10A-B the ophthalmic system 100 projects a collimated fixation light 145 to the eye. However, since the collimator 142 makes the rays of the fixation light 145 essentially parallel, the patient may not be able to see the collimated fixation light 145 from a typical misaligned initial position. In such systems, the patient 8 may not be able to follow instructions to align the imaged eye with the collimated fixation light 145 and may need assistance.
[00143] Some embodiments may assist the alignment process in these collimator implementations with providing the locator light 175', focused at the second focal point 176. Since the locator light 175' is not collimated, the patient 8 is able to see the second focal point 176 even from misaligned positions. In these embodiments, after the patient 8 fixates on the locator light 175', the image processor 120' can subsequently move or adjust the locator light 175' (shown by the solid arrow) to assist the patient to rotate and move the imaged eye until the patient sees the collimated fixation light 145'.
[00144] FIG. 21 illustrates that some ophthalmic systems 100" can also include a procedure laser 190. The procedure laser 190 can be used to perform an ophthalmic surgical procedure after the high precision alignment and docking made possible by the misalignment reduction system 130. The surgical procedure can include a cataract surgery, a refractive procedure, a retina-related procedure and a wide variety of other ophthalmic procedures.
[00145] Some of these ophthalmic systems 100" may also include a secondary imaging system 195. This secondary imaging system 195 can include an optical coherence tomographic (OCT) system. OCT systems, especially the spectrometer based frequency-domain type, are well suited to image three dimensional ophthalmic target regions, as they are capable of acquiring image data from all depth of the target region simultaneously. The beams of the procedure laser 190 and the secondary imaging system 195 can be coupled into the main optical pathway by beam splitters BS1 and BS2, respectively. Such systems may combine the z-directional imaging functionality of the OCT imaging system 195 with the above described image processing-based alignment procedure to achieve alignment both with visible ophthalmic structures as well as with targets inside the eye.
[00146] FIG. 22 illustrates an operation of the above described ophthalmic systems 100-100'-100". A method 200 of aligning an eye with the ophthalmic system 100-100'- 100" can include the following phases, (a) A generating of an image 210 that generates an image of a portion of the imaged eye li of a patient by the ophthalmic imaging device 100-100'-100". (b) A determining a misalignment 220 that determines the misalignment of the imaged eye li and the imaging device 1 10 by an image processor 120 processing the generated image, (c) A generating a misalignment-reduction response 230 that generates a misalignment-reduction response electronically by a misalignment-reduction system based on the determined misalignment.
[00147] The generating an image 210 can include generating an image 212 of a portion of the imaged eye 1 i with the imaging device 1 10-1 1 0'- l 10". [00148] The determining the misalignment 220 can include (1) identifying an ophthalmic structure 222 in the image 212. The ophthalmic structure can be the pupil 4, the lens 5, and the limbus 6, among others. The determining 220 can also include (2) determining the misalignment by determining a location of the ophthalmic structure 222 relative to a reference of the imaging device by the image processor 120. The reference of the imaging device can be the objective 1 12, a patient module, a docking tip, an interface, a contact lens, a pupil, a viewing frame, a reference frame, an internal lens of the ophthalmic system, or a reference pattern 1 17 generated by the imaging device 1 10-1 10'- 1 10". The misalignment can be a lateral or an angular misalignment, determined by the image processor 120 by analyzing the image using software implementations. Finally, (3) the image processor 120 can generate a control signal according to the determined misalignment and output the generated control signal to the misalignment-reduction system 130.
[00149] The generating the misalignment-reduction response 230 can include generating the misalignment-reduction response 230 by the misalignment reduction system 130. In some embodiments, the generating the misalignment-reduction response 230 can include generating the fixation light 145 by the fixation light source 140 according to the misalignment determined by the image processor 120, in response to the control signal from the image processor 120. The fixation light 145 can guide the patient 8 to reduce an angular or a lateral misalignment.
[00150] In an implementation, the fixation light source 140 may include a collimator 142 to generate the fixation light 145 to guide the patient 8 to reduce a lateral
misalignment. The fixation light 145 can be generated for the non-imaged, or control eye lc, and the fixation light 145 can be adjusted according to the determined misalignment to assist the patient to reduce the misalignment. In other implementations, the fixation light 145 can be generated for the imaged eye li.
[00151] The generating the misalignment-reduction response 230 can include the gantry controller 150 moving the gantry 155 of the imaging device 1 10 to reduce a lateral misalignment. In other embodiments, the gantry controller 150 can move the bed 168, or a combination of the bed 168 and the gantry 155. [00152] The determining the misalignment 220 can include determining an angular and a lateral misalignment by the image processor 120 processing the image and an additional misalignment information. Correspondingly, the generating the misalignment- reduction response 230 can include operating the fixation light system 140 and the gantry controller 150 to reduce the angular and the lateral misalignment.
[00153] The determining the misalignment 220 can include (1) projecting the locator light 175 onto the imaged eye li by the locator light source 170, (2) locating an image 177 i of the apical reflected locator light 177 in the image generated by the imaging device 1 10, and (3) determining the misalignment information using the located imaged apical reflected locator light 177i.
[00154] The determining the misalignment information 220 can include determining an angular misalignment information, related to a distance or vector between the image of the apical reflected locator light 177i and a location of an imaged ophthalmic structure; and determining a lateral misalignment information, related to a distance or vector between the imaged apical reflected locator light 177i or the location of the imaged ophthalmic structure and a reference of the imaging system. The generating the misalignment-reduction response 230 can include reducing the angular misalignment by adjusting the fixation light system 140 and reducing the lateral misalignment by operating the gantry controller 150. As the first phase of reducing the misalignment may only reduce the misalignment but not eliminate it, the reducing the angular misalignment and the reducing the lateral misalignment phases can be repeated iteratively and alternately in some implementations.
[00155] In some embodiments, the generating the misalignment-reduction response 230 can include using the locator light as a second fixation light 175'. In these embodiments, the reducing the lateral and the angular misalignment can include instructing the patient 8 to align the first fixation light 145' and the locator/second fixation light 175'.
[00156] Finally, some implementations of the ophthalmic imaging system may include an imaging device that generates an image of an imaged eye of the patient and a processor that determines a misalignment of the imaged eye and the imaging device by processing the generated image. The processor can control a fixation light system to project a fixation light on an eye of the patient to reduce an angular misalignment, and control a gantry to adjust a movable optical element of the system to reduce a lateral misalignment.
[00157] Some implementation of the ophthalmic imaging system can include an indicator light system that projects an indicator light on the imaged eye to provide misalignment information for the processor.
[00158] While this specification contains many specifics, these should not be construed as limitations on the scope of the invention or of what can be claimed, but rather as descriptions of features specific to particular embodiments. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination. Moreover, although features can be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination can be directed to a subcombination or variation of a subcombination.

Claims

1. An ophthalmic system, comprising:
an ophthalmic imaging device configured to generate an image of a portion of an imaged eye of a patient;
an image processor, configured
to determine a misalignment of the imaged eye and the imaging device by processing the generated image, and
to generate a control signal according to the determined misalignment; and a misalignment-reduction system, configured
to receive the control signal, and
to generate a misalignment-reduction response.
2. The ophthalmic system of claim 1 , the ophthalmic imaging device comprising:
an electronic sensing system that senses a collected imaging light from the imaged eye, including at least one of
a Charge-Coupled Device (CCD) array, a Complementary Metal-Oxide Semiconductor (CMOS) array, a pixel-array, and an electronic sensor array; and
an electronic display system that displays the image of a portion of the imaged eye in relation to the sensed collected imaging light, including at least one of
a Light Emitting Diode (LED) display, an organic LED (OLED) display, an active matrix OLED (AMOLED) display, an a plasma screen, an electronic display, a computer display, a Liquid Crystal Display (LCD) screen, a Cathode Ray Tube (CRT) display, a video-module, a video microscope display, a stereo video microscope display, a high definition (HD) video microscope, a processor-based image system, an opto-mechanical projector of the electronic or digital type, and a light-source movable by an electro-mechanical actuator.
3. The ophthalmic system of claim 1 , wherein:
the image processor is configured
to identify an ophthalmic structure in the image, and
to determine a measure of misalignment by determining a location of the ophthalmic structure relative to a reference of the imaging device.
4. The ophthalmic system of claim 3, wherein:
the image processor is configured to identify the ophthalmic structure by determining a high-gradient line in the image, separating image elements with substantially different brightness or color.
5. The ophthalmic system of claim 4, wherein:
the image processor is configured
to fit at least one of a circle and an ellipse to the high-gradient line by measuring radial distances between the high-gradient line and the circle or ellipse; to determine a location coordinate of the fitted circle or ellipse by minimizing a measure of the radial distances; and
to determine a misalignment-measure by relating the determined location coordinate and a coordinate of the reference.
6. The ophthalmic system of claim 3, wherein:
the image processor is configured
to determine a high-contrast line in the image;
to determine misalignment distances between the high-contrast line and a targeting pattern; and
to determine a misalignment-measure from the misalignment distances.
7. The ophthalmic system of claim 3, wherein: the reference of the imaging device is at least one of
an objective, a patient module, a docking tip, an interface, a contact lens, a pupil, a viewing frame, a reference frame, and an internal lens of the ophthalmic system; and
the imaging device is configured to generate a reference pattern related to the reference to assist the image processor to determine the misalignment of the imaged eye and the imaging device.
8. The ophthalmic system of claim 3, wherein:
the recognized ophthalmic structure is a limbus of the imaged eye.
9. The ophthalmic system of claim 1 , wherein:
at least a portion of the image processed by the image processor is not displayed by the imaging device.
10. The ophthalmic system of claim 1 , wherein:
the misalignment-reduction system comprises a fixation light source; and the misalignment-reduction response comprises the fixation light source generating a fixation light in response to the received control signal.
1 1. The ophthalmic system of claim 10, wherein:
the fixation light source is configured
to generate the fixation light for a non-imaged eye of the patient; and to move the generated fixation light according to the received control signal to assist a reduction of a misalignment between the imaged eye and a reference- component of the ophthalmic system.
12. The ophthalmic system of claim 10, the fixation light source comprising at least one of:
a LED array, an organic LED (OLED) array, an active matrix OLED (AMOLED) array, a plasma screen, an electronic display, a computer display, an LCD screen, a video-module, an opto-mechanical projector, a CRT display, a slit-lamp, a processor- based image system, and a light-source movable by an electro-mechanical actuator.
13. The ophthalmic system of claim 10, wherein:
the fixation light source is configured to generate the fixation light to guide the patient to reduce an angular misalignment.
14. The ophthalmic system of claim 13, wherein:
the image processor is configured to determine the angular misalignment by
fitting an ellipse to a high-contrast line of the image; and
analyzing at least one of an aspect ratio and an area of the fitted ellipse.
15. The ophthalmic system of claim 10, wherein:
the fixation light source comprises a collimator to generate a fixation light to guide the patient to reduce a lateral misalignment.
16. The ophthalmic system of claim 1, wherein:
the misalignment-reduction system comprises
a gantry, configured to move a movable portion of the imaging device; and a gantry controller, configured
to receive the control signal from the image processor, and
to move the gantry according to the received control signal; and the misalignment-reduction response comprises the gantry controller moving the gantry and thus the movable portion of the imaging device to reduce a lateral misalignment.
17. The ophthalmic system of claim 16, wherein:
the gantry is also part of the ophthalmic imaging device.
18. The ophthalmic system of claim 1 , wherein:
the misalignment-reduction system comprises
a support-gantry, configured to move a patient support relative to the imaging device; and
a gantry controller, configured to receive the control signal from the image processor, and
to move the support-gantry according to the received control signal; and the misalignment-reduction response comprises the gantry controller moving the support-gantry and thus the patient support to reduce a lateral misalignment.
19. The ophthalmic system of claim 1 , wherein:
the image processor is configured to determine an angular and a lateral misalignment by processing the image; and
the misalignment-reduction system comprises only one of a fixation light source and a gantry controller.
20. The ophthalmic system of claim 1 , wherein:
the image processor is configured to determine an angular and a lateral misalignment; and
the misalignment-reduction system comprises a fixation light source, a gantry and a gantry controller.
21. The ophthalmic system of claim 20, wherein:
the image processor is configured to determine an angular and a lateral
misalignment by processing the image and a misalignment information.
22. The ophthalmic system of claim 21 , wherein:
the imaging system comprises a locator light source, configured to project a locator light on the imaged eye; and
the image processor is configured
to identify an apical reflected locator light in the image generated by the imaging device; and
to determine the misalignment information by analyzing the apical reflected locator light.
23. The ophthalmic system of claim 22, wherein:
the misalignment information is at least one of
an angular misalignment information, related to a vector in the image between the apical reflected locator light and a location of an imaged ophthalmic structure; and
a lateral misalignment information, related to a vector in the image between a reference of the imaging system and at least one of the apical reflected locator light and the location of an imaged ophthalmic structure.
24. The ophthalmic system of claim 23, wherein: the ophthalmic system is configured
to reduce the angular misalignment by adjusting the fixation light source; and to reduce the lateral misalignment by operating the gantry controller.
25. The ophthalmic system of claim 22, wherein:
the fixation light is adjustable so that the locator light and a location of an imaged ophthalmic structure can be aligned by adjusting the fixation light.
26. The ophthalmic system of claim 22, wherein:
the fixation light source and the locator light source are capable of operating at different wavelengths.
27. The ophthalmic system of claim 26, wherein:
the locator light is invisible for the imaged eye.
28. The ophthalmic system of claim 1 , comprising:
a patient interface, configured to dock to the imaged eye of the patient after the misalignment-reduction system executed the misalignment-reduction response.
29. The ophthalmic system of claim 1 , wherein:
the misalignment-reduction system comprises a fixation light source, configured to generate a fixation light for the imaged eye of the patient; and
to adjust the generated fixation light according to the received control signal to assist a reduction of a misalignment between the imaged eye and a reference- component of the ophthalmic system.
30. The ophthalmic system of claim 29, comprising:
a locator light, focusable to a second focal point different from a first focal point of the fixation light.
31. A method of aligning an eye with an ophthalmic system, the method comprising: generating an image of a portion of an imaged eye of a patient by an ophthalmic imaging device;
determining a misalignment of the imaged eye and the imaging device by an image processor processing the generated image; and
generating a misalignment-reduction response electronically by a misalignment- reduction system based on the determined misalignment.
32. The method of claim 31 , the determining the misalignment comprising: identifying an ophthalmic structure in the image; and
determining a location of the ophthalmic structure relative to a reference of the imaging device.
33. The method of claim 31 , the generating the misalignment-reduction response comprising:
generating a fixation light by a fixation light source according to the determined misalignment.
34. The method of claim 33, the generating the fixation light comprising: generating the fixation light to guide the patient to reduce an angular
misalignment.
35. The method of claim 33, the generating the fixation light comprising: generating a fixation light to guide the patient to reduce a lateral misalignment, wherein
the fixation light source comprises a collimator.
36. The method of claim 33, wherein:
the generating the fixation light comprises generating the fixation light for a non-imaged eye of the patient; and the generating the misalignment-reduction response comprises
adjusting the fixation light according to the determined misalignment to assist the patient to reduce the misalignment.
37. The method of claim 33, wherein:
the generating the fixation light comprises
generating the fixation light for the imaged eye of the patient; and the generating the misalignment-reduction response comprises
adjusting the fixation light according to the determined misalignment to assist the patient to reduce the misalignment.
38. The method of claim 31 , the generating the misalignment-reduction response comprising:
moving a gantry of the imaging system by a gantry controller to reduce a lateral misalignment.
39. The method of claim 31, wherein:
the determining the misalignment comprises
determining an angular and a lateral misalignment by the image processor processing the image and a misalignment information; and
the generating the misalignment-reduction response comprises
adjusting a fixation light of a fixation light system and a gantry controller.
40. The method of claim 39, the determining the misalignment comprising: projecting a locator light onto the imaged eye by a locator light system; locating an apical reflected locator light in the image generated by the imaging device; and
determining the misalignment information using the located apical reflected locator light.
41. The method of claim 40, the determining the misalignment information comprising:
determining an angular misalignment information, related to a vector in the image between the apical reflected locator light and a location of an imaged ophthalmic structure; and determining a lateral misalignment information, related to a vector in the image between a reference of the imaging system and at least one of the apical reflected locator light and the imaged ophthalmic structure.
42. The method of claim 41 , the generating the misalignment-reduction response comprising:
reducing the angular misalignment by adjusting the fixation light; and
reducing the lateral misalignment by operating the gantry controller.
43. The method of claim 42, wherein:
the reducing the angular misalignment and the reducing the lateral misalignment are repeated iteratively.
44. The method of claim 40, the generating the misalignment-reduction response comprising:
projecting the fixation light into the imaged eye; and
reducing the lateral and the angular misalignment by causing the head of the patient to move laterally to align the locator light and the fixation light.
45. An ophthalmic system, comprising:
an imaging device that generates an image of an imaged eye of a patient;
an image processor that determines an angular and a lateral misalignment of the imaged eye and the imaging device by processing the generated image;
a fixation light system that projects a fixation light on an eye of the patient to assist a reduction of the angular misalignment; and
a gantry that adjusts a movable optic of the system to reduce the lateral
misalignment.
46. The ophthalmic system of claim 45, comprising:
an indicator light system that projects an indicator light on the imaged eye to provide a misalignment information for the image processor.
PCT/US2012/035927 2011-05-02 2012-05-01 Image-processor-controlled misalignment-reduction for ophthalmic systems WO2012151172A2 (en)

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EP12720361.0A EP2680740B1 (en) 2011-05-02 2012-05-01 Image-processor-controlled misalignment-reduction for ophthalmic systems
JP2014509349A JP5795684B2 (en) 2011-05-02 2012-05-01 Mismatch reduction controlled by an image processor for ophthalmic systems
AU2012250897A AU2012250897B2 (en) 2011-05-02 2012-05-01 Image-processor-controlled misalignment-reduction for ophthalmic systems
CA2832093A CA2832093C (en) 2011-05-02 2012-05-01 Image-processor-controlled misalignment-reduction for ophthalmic systems
MX2013012626A MX336512B (en) 2011-05-02 2012-05-01 Image-processor-controlled misalignment-reduction for ophthalmic systems.
KR1020137031988A KR101640536B1 (en) 2011-05-02 2012-05-01 Image-processor-controlled misalignment-reduction for ophthalmic systems
RU2013153220/14A RU2593745C2 (en) 2011-05-02 2012-05-01 Reduced violation of alignment under control of image processor for ophthalmological systems
ES12720361.0T ES2610562T3 (en) 2011-05-02 2012-05-01 Misalignment reduction controlled by an image processor for ophthalmic systems
CN201280021411.8A CN103687532B (en) 2011-05-02 2012-05-01 The misalignment controlled for the image processor of ophthalmic system reduces

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Families Citing this family (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9655517B2 (en) 2012-02-02 2017-05-23 Visunex Medical Systems Co. Ltd. Portable eye imaging apparatus
US20150021228A1 (en) 2012-02-02 2015-01-22 Visunex Medical Systems Co., Ltd. Eye imaging apparatus and systems
US9351639B2 (en) 2012-03-17 2016-05-31 Visunex Medical Systems Co. Ltd. Eye imaging apparatus with a wide field of view and related methods
TWI572331B (en) * 2012-12-28 2017-03-01 國立交通大學 Rotation type optical fault scanner
KR102360176B1 (en) * 2014-03-21 2022-02-09 삼성전자주식회사 Method and wearable device for providing a virtual input interface
US9986908B2 (en) 2014-06-23 2018-06-05 Visunex Medical Systems Co. Ltd. Mechanical features of an eye imaging apparatus
WO2016123138A1 (en) 2015-01-26 2016-08-04 Visunex Medical Systems Co. Ltd. A disposable cap for an eye imaging apparatus and related methods
JP2017079904A (en) * 2015-10-26 2017-05-18 ソニー株式会社 Surgical microscope, image processing device, and image processing method
AT518602B1 (en) * 2016-05-03 2019-02-15 Zeiss Carl Meditec Ag Ophthalmic length measurement using a double-beam space-time domain Wavelength Tuning Short-coherence interferometry
EP3481347A1 (en) 2016-07-06 2019-05-15 Amo Wavefront Sciences, LLC Retinal imaging for reference during laser eye surgery
CN106510614B (en) * 2016-12-14 2018-11-23 广州优里卡光电科技有限公司 Fundus Image Inspection System with flexible color screen
CN111511268B (en) 2017-11-07 2023-12-26 诺达尔视觉有限公司 Retinal imaging apparatus and associated methods
CN111542258B (en) * 2017-11-07 2023-10-20 诺达尔视觉有限公司 Method and system for alignment of ophthalmic imaging devices
US11147441B2 (en) 2018-01-16 2021-10-19 Welch Allyn, Inc. Physical assessment device
AU2019251316B2 (en) * 2018-04-11 2024-08-01 Alcon Inc. Automatic XY centering for digital microscope
US10595722B1 (en) 2018-10-03 2020-03-24 Notal Vision Ltd. Automatic optical path adjustment in home OCT
US10932864B2 (en) * 2018-11-28 2021-03-02 Rxsight, Inc. Tracking-based illumination control system
US11013593B2 (en) 2018-12-02 2021-05-25 Rxsight, Inc. Light adjustable lens tracking system and method
EP3945994B1 (en) 2019-03-27 2024-10-23 Alcon Inc. System and method of utilizing one or more images of an eye in medical procedures
US10653311B1 (en) 2019-06-12 2020-05-19 Notal Vision Ltd. Home OCT with automatic focus adjustment
CN110251072A (en) * 2019-07-03 2019-09-20 深圳市龙华区中心医院 Pupil electronic observation device and pupil monitor system
RU201585U1 (en) * 2020-06-11 2020-12-22 федеральное государственное бюджетное образовательное учреждение высшего образования "Ижевский государственный технический университет имени М.Т. Калашникова" Excimer laser vision correction device

Family Cites Families (208)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SU728869A1 (en) 1976-07-12 1980-04-25 Физический Институт Им. П.Н.Лебедева Ан Ссср Laser ophtalmology apparatus
JPS5926298B2 (en) 1977-02-18 1984-06-26 東京光学機械株式会社 Crystalline lens cross-section imaging device
JPS5926300B2 (en) 1977-02-21 1984-06-26 東京光学機械株式会社 Eyeball lens cross-section imaging device
JPS5663330A (en) 1979-10-25 1981-05-29 Canon Kk Inspecting machine for eye
DE3045139A1 (en) 1980-11-29 1982-07-01 Fa. Carl Zeiss, 7920 Heidenheim DEVICE FOR SUBJECTIVE AND OBJECTIVE REFLECTION DETERMINATION
FR2524298A1 (en) 1982-04-01 1983-10-07 Essilor Int LASER OPHTHALMOLOGICAL SURGICAL APPARATUS
US4520816A (en) 1983-01-12 1985-06-04 Schachar Ronald A Method and apparatus for delivering laser energy for ophthalmic use
US4638801A (en) 1983-07-06 1987-01-27 Lasers For Medicine Laser ophthalmic surgical system
US4538608A (en) 1984-03-23 1985-09-03 Esperance Jr Francis A L Method and apparatus for removing cataractous lens tissue by laser radiation
US4764005A (en) 1985-09-17 1988-08-16 Eye Research Institute Of Retina Foundation Double scanning optical apparatus
US5112328A (en) 1988-01-25 1992-05-12 Refractive Laser Research & Development Program, Ltd. Method and apparatus for laser surgery
US4901718A (en) 1988-02-02 1990-02-20 Intelligent Surgical Lasers 3-Dimensional laser beam guidance system
US4881808A (en) 1988-02-10 1989-11-21 Intelligent Surgical Lasers Imaging system for surgical lasers
US4907586A (en) 1988-03-31 1990-03-13 Intelligent Surgical Lasers Method for reshaping the eye
US5098426A (en) 1989-02-06 1992-03-24 Phoenix Laser Systems, Inc. Method and apparatus for precision laser surgery
US6099522A (en) 1989-02-06 2000-08-08 Visx Inc. Automated laser workstation for high precision surgical and industrial interventions
IL89874A0 (en) 1989-04-06 1989-12-15 Nissim Nejat Danon Apparatus for computerized laser surgery
US5054907A (en) 1989-12-22 1991-10-08 Phoenix Laser Systems, Inc. Ophthalmic diagnostic apparatus and method
US5048946A (en) 1990-05-15 1991-09-17 Phoenix Laser Systems, Inc. Spectral division of reflected light in complex optical diagnostic and therapeutic systems
US5779696A (en) 1990-07-23 1998-07-14 Sunrise Technologies International, Inc. Method and apparatus for performing corneal reshaping to correct ocular refractive errors
EP0496870A4 (en) 1990-08-22 1993-01-07 Phoenix Laser Systems, Inc. System for scanning a surgical laser beam
US5139022A (en) 1990-10-26 1992-08-18 Philip Lempert Method and apparatus for imaging and analysis of ocular tissue
US5162641A (en) 1991-02-19 1992-11-10 Phoenix Laser Systems, Inc. System and method for detecting, correcting and measuring depth movement of target tissue in a laser surgical system
WO1992019930A1 (en) 1991-04-29 1992-11-12 Massachusetts Institute Of Technology Method and apparatus for optical imaging and measurement
US5255025A (en) 1991-10-15 1993-10-19 Volk Donald A Measurement apparatus for indirect ophthalmoscopy
US5439462A (en) 1992-02-25 1995-08-08 Intelligent Surgical Lasers Apparatus for removing cataractous material
US5246435A (en) 1992-02-25 1993-09-21 Intelligent Surgical Lasers Method for removing cataractous material
US5549632A (en) 1992-10-26 1996-08-27 Novatec Laser Systems, Inc. Method and apparatus for ophthalmic surgery
US5336215A (en) 1993-01-22 1994-08-09 Intelligent Surgical Lasers Eye stabilizing mechanism for use in ophthalmic laser surgery
US5954711A (en) 1993-12-28 1999-09-21 Nidek Co., Ltd. Laser treatment apparatus
US5656186A (en) 1994-04-08 1997-08-12 The Regents Of The University Of Michigan Method for controlling configuration of laser induced breakdown and ablation
ES2233727T3 (en) 1994-08-18 2005-06-16 Carl Zeiss Meditec Ag SURGICAL DEVICE ASSISTED BY OPTICAL COHERENCE TOMOGRAPHY.
US5493109A (en) 1994-08-18 1996-02-20 Carl Zeiss, Inc. Optical coherence tomography assisted ophthalmologic surgical microscope
US5738676A (en) 1995-01-03 1998-04-14 Hammer; Daniel X. Laser surgical probe for use in intraocular surgery
US6454761B1 (en) 1995-01-30 2002-09-24 Philip D. Freedman Laser surgery device and method
WO1997040763A1 (en) 1996-04-29 1997-11-06 Philips Electronics N.V. Image guided surgery system
US5795295A (en) 1996-06-25 1998-08-18 Carl Zeiss, Inc. OCT-assisted surgical microscope with multi-coordinate manipulator
US6167296A (en) 1996-06-28 2000-12-26 The Board Of Trustees Of The Leland Stanford Junior University Method for volumetric image navigation
US6437867B2 (en) 1996-12-04 2002-08-20 The Research Foundation Of The City University Of New York Performing selected optical measurements with optical coherence domain reflectometry
US5777719A (en) 1996-12-23 1998-07-07 University Of Rochester Method and apparatus for improving vision and the resolution of retinal images
US5994690A (en) 1997-03-17 1999-11-30 Kulkarni; Manish D. Image enhancement in optical coherence tomography using deconvolution
DE19718139A1 (en) 1997-04-30 1998-11-05 Aesculap Meditec Gmbh Phaco-emulsification method for intra=ocular tissue removal
JP3313309B2 (en) 1997-08-21 2002-08-12 株式会社トプコン Ophthalmic equipment
ES2183447T3 (en) 1998-03-09 2003-03-16 Medizinisches Laserzentrum Lub PROCEDURE AND DEVICE INTENDED TO EXAMINE AN EYE SEGMENT.
DE19814057B4 (en) 1998-03-30 2009-01-02 Carl Zeiss Meditec Ag Arrangement for optical coherence tomography and coherence topography
WO1999055216A2 (en) 1998-04-27 1999-11-04 Ming Lai Optical tracking device
US6137585A (en) 1998-05-15 2000-10-24 Laser Diagnostic Technologies, Inc. Method and apparatus for recording three-dimensional distribution of light backscattering potential in transparent and semi-transparent structures
US6045227A (en) * 1998-09-03 2000-04-04 Visionrx.Com, Inc. Multi-functional visual testing instrument
EP1125095B1 (en) 1998-09-11 2008-02-27 Joseph A. Izatt Interferometers for optical coherence domain reflectometry and optical coherence tomography using nonreciprocal optical elements
US6623476B2 (en) 1998-10-15 2003-09-23 Intralase Corp. Device and method for reducing corneal induced aberrations during ophthalmic laser surgery
US6254595B1 (en) 1998-10-15 2001-07-03 Intralase Corporation Corneal aplanation device
US6497701B2 (en) 1999-04-30 2002-12-24 Visx, Incorporated Method and system for ablating surfaces with partially overlapping craters having consistent curvature
DE19930408A1 (en) 1999-07-02 2001-01-04 Zeiss Carl Fa An optical coherence computer tomography (OCT) system for surgical support combines pre-operation tissue position data and CT data for use in navigation assistance for the operating surgeon
US6817998B2 (en) 1999-07-23 2004-11-16 Lahaye Leon C. Method and apparatus for monitoring laser surgery
US6314311B1 (en) 1999-07-28 2001-11-06 Picker International, Inc. Movable mirror laser registration system
US6932807B1 (en) 1999-09-01 2005-08-23 Nidek Co., Ltd. Laser treatment apparatus
US6687010B1 (en) 1999-09-09 2004-02-03 Olympus Corporation Rapid depth scanning optical imaging device
ATE398433T1 (en) 1999-09-10 2008-07-15 Haag Ag Streit DEVICE FOR PHOTOABLING THE CORNEA USING A LASER BEAM
US6317616B1 (en) 1999-09-15 2001-11-13 Neil David Glossop Method and system to facilitate image guided surgery
US6337925B1 (en) 2000-05-08 2002-01-08 Adobe Systems Incorporated Method for determining a border in a complex scene with applications to image masking
DE10024079A1 (en) 2000-05-17 2001-11-22 Asclepion Meditec Ag Determining energy and position of pulsed laser beam of ophthalmologic excimer laser for cornea surgery, deflects beam periodically onto measurement sensor
WO2001091661A1 (en) 2000-06-01 2001-12-06 The General Hospital Corporation Selective photocoagulation
US6652459B2 (en) 2000-06-28 2003-11-25 Peter Alfred Payne Ophthalmic uses of lasers
US7025459B2 (en) 2000-07-14 2006-04-11 Visual Pathways, Inc. Ocular fundus auto imager
US6451009B1 (en) 2000-09-12 2002-09-17 The Regents Of The University Of California OCDR guided laser ablation device
US20020082466A1 (en) 2000-12-22 2002-06-27 Jeongho Han Laser surgical system with light source and video scope
DE10100857B4 (en) 2001-01-11 2006-05-18 Carl Zeiss Jena Gmbh Laser slit lamp with laser radiation source
US6863667B2 (en) 2001-01-29 2005-03-08 Intralase Corp. Ocular fixation and stabilization device for ophthalmic surgical applications
US6899707B2 (en) 2001-01-29 2005-05-31 Intralase Corp. Applanation lens and method for ophthalmic surgical applications
AU2002240155A1 (en) 2001-01-29 2002-09-19 Joseph A. Izatt Frequency-encoded parallel oct and associated systems and methods
US20080071254A1 (en) 2001-01-29 2008-03-20 Advanced Medical Optics, Inc. Ophthalmic interface apparatus and system and method of interfacing a surgical laser with an eye
US6579282B2 (en) 2001-04-25 2003-06-17 20/10 Perfect Vision Optische Geraete Gmbh Device and method for creating a corneal reference for an eyetracker
JP2002345758A (en) 2001-05-25 2002-12-03 Canon Inc Ophthalmic imaging device
AU2002337666A1 (en) 2001-08-03 2003-02-17 Joseph A. Izatt Aspects of basic oct engine technologies for high speed optical coherence tomography and light source and other improvements in oct
US6751033B2 (en) 2001-10-12 2004-06-15 Intralase Corp. Closed-loop focal positioning system and method
US7027233B2 (en) 2001-10-12 2006-04-11 Intralase Corp. Closed-loop focal positioning system and method
US6980299B1 (en) 2001-10-16 2005-12-27 General Hospital Corporation Systems and methods for imaging a sample
US7006231B2 (en) 2001-10-18 2006-02-28 Scimed Life Systems, Inc. Diffraction grating based interferometric systems and methods
US7341349B2 (en) * 2001-11-15 2008-03-11 Kabushiki Kaisha Topcon Ophthalmologic apparatus and ophthalmologic chart
AU2003207507A1 (en) 2002-01-11 2003-07-30 Gen Hospital Corp Apparatus for oct imaging with axial line focus for improved resolution and depth of field
US7072045B2 (en) 2002-01-16 2006-07-04 The Regents Of The University Of California High resolution optical coherence tomography with an improved depth range using an axicon lens
US7355716B2 (en) 2002-01-24 2008-04-08 The General Hospital Corporation Apparatus and method for ranging and noise reduction of low coherence interferometry LCI and optical coherence tomography OCT signals by parallel detection of spectral bands
WO2003068103A2 (en) 2002-02-11 2003-08-21 Visx, Inc. Closed loop system and method for ablating lenses with aberrations
US20030171809A1 (en) 2002-03-05 2003-09-11 Phillips Andrew F. Axial-displacement accommodating intraocular lens
US7006232B2 (en) 2002-04-05 2006-02-28 Case Western Reserve University Phase-referenced doppler optical coherence tomography
US7113818B2 (en) 2002-04-08 2006-09-26 Oti Ophthalmic Technologies Inc. Apparatus for high resolution imaging of moving organs
US6741359B2 (en) 2002-05-22 2004-05-25 Carl Zeiss Meditec, Inc. Optical coherence tomography optical scanner
US6730074B2 (en) 2002-05-24 2004-05-04 20/10 Perfect Vision Optische Geraete Gmbh Cornea contact system for laser surgery
WO2003105678A2 (en) 2002-06-12 2003-12-24 Advanced Research And Technology Institute, Inc. Method and apparatus for improving both lateral and axial resolution in ophthalmoscopy
US7133137B2 (en) 2002-06-27 2006-11-07 Visx, Incorporated Integrated scanning and ocular tomography system and method
CA2390072C (en) 2002-06-28 2018-02-27 Adrian Gh Podoleanu Optical mapping apparatus with adjustable depth resolution and multiple functionality
US7072047B2 (en) 2002-07-12 2006-07-04 Case Western Reserve University Method and system for quantitative image correction for optical coherence tomography
JP4503913B2 (en) 2002-07-23 2010-07-14 株式会社東芝 Printing method
JP2006503432A (en) 2002-10-17 2006-01-26 ルメニス・インコーポレーテッド System, method and apparatus for supplying laser beams of two or more wavelengths
DE10252837B4 (en) 2002-11-13 2005-03-24 Carl Zeiss Examination system and examination procedure
US6887232B2 (en) 2002-11-13 2005-05-03 20/10 Perfect Vision Optische Geraete Gmbh Closed loop control for intrastromal wavefront-guided ablation
DE10300091A1 (en) 2003-01-04 2004-07-29 Lubatschowski, Holger, Dr. microtome
EP1592992B1 (en) 2003-01-24 2012-05-30 University of Washington Optical beam scanning system for compact image display or image acquisition
DE10304221A1 (en) 2003-01-30 2004-08-12 Carl Zeiss Surgical assistance device for assisting a surgeon in the removal of tissue, e.g. for cancer treatment, whereby movement of an operating instrument is at least partially automated based on tissue measurements
US7846152B2 (en) 2004-03-24 2010-12-07 Amo Manufacturing Usa, Llc. Calibrating laser beam position and shape using an image capture device
WO2004088241A2 (en) 2003-03-26 2004-10-14 Southwest Sciences Incorporated Method and apparatus for imaging internal structures of transparent and translucent materials
US7742804B2 (en) 2003-03-27 2010-06-22 Ivan Faul Means of tracking movement of bodies during medical treatment
WO2004098396A2 (en) 2003-05-01 2004-11-18 The Cleveland Clinic Foundation Method and apparatus for measuring a retinal sublayer characteristic
US6927860B2 (en) 2003-05-19 2005-08-09 Oti Ophthalmic Technologies Inc. Optical mapping apparatus with optimized OCT configuration
US7035025B2 (en) 2003-05-28 2006-04-25 Agilent Technologies, Inc. Compact precision beam manipulators
US7311723B2 (en) 2003-07-11 2007-12-25 University Of Washington Scanning laser device and methods of use
DE10360570B4 (en) 2003-12-22 2006-01-12 Carl Zeiss Optical measuring system and optical measuring method
US7252661B2 (en) 2003-12-23 2007-08-07 Alcon Refractivehorizons, Inc. Method and system for patient optical fixation
US7145661B2 (en) 2003-12-31 2006-12-05 Carl Zeiss Meditec, Inc. Efficient optical coherence tomography (OCT) system and method for rapid imaging in three dimensions
JP4391259B2 (en) 2004-02-03 2009-12-24 株式会社ニデック Ophthalmic equipment
WO2005077256A1 (en) 2004-02-06 2005-08-25 Optovue, Inc. Optical apparatus and methods for performing eye examinations
EP1713377A1 (en) 2004-02-10 2006-10-25 Optovue, Inc. High efficiency low coherence interferometry
GB2411066B (en) 2004-02-14 2009-04-29 Oti Ophthalmic Technologies Compact high resolution imaging apparatus
US7402159B2 (en) 2004-03-01 2008-07-22 20/10 Perfect Vision Optische Geraete Gmbh System and method for positioning a patient for laser surgery
KR101000926B1 (en) 2004-03-11 2010-12-13 삼성전자주식회사 Filter for removing blocking effect and filtering method thereof
JP4522724B2 (en) 2004-03-16 2010-08-11 株式会社トプコン Optical image measuring device
US7126693B2 (en) 2004-03-29 2006-10-24 Carl Zeiss Meditec, Inc. Simple high efficiency optical coherence domain reflectometer design
JP4409332B2 (en) 2004-03-30 2010-02-03 株式会社トプコン Optical image measuring device
US7813644B2 (en) 2004-05-10 2010-10-12 Raytheon Company Optical device with a steerable light path
US7184148B2 (en) 2004-05-14 2007-02-27 Medeikon Corporation Low coherence interferometry utilizing phase
WO2005122872A2 (en) 2004-06-10 2005-12-29 Optimedica Corporation Scanning ophthalmic fixation method and apparatus
WO2006002392A2 (en) 2004-06-24 2006-01-05 Optimedica Corporation Ophthalmic lens assembly utilizing replaceable contact element
US7352444B1 (en) 2004-06-24 2008-04-01 Cypress Semiconductor Corp. Method for arranging and rotating a semiconductor wafer within a photolithography tool prior to exposing the wafer
US11026860B2 (en) 2004-06-28 2021-06-08 Iridex Method and device for optical ophthalmic therapy
DE102004035269A1 (en) 2004-07-21 2006-02-16 Rowiak Gmbh Laryngoscope with OCT
JP4409384B2 (en) 2004-08-03 2010-02-03 株式会社トプコン Optical image measuring device and optical image measuring method
US7433046B2 (en) 2004-09-03 2008-10-07 Carl Ziess Meditec, Inc. Patterned spinning disk based optical phase shifter for spectral domain optical coherence tomography
US7365859B2 (en) 2004-09-10 2008-04-29 The General Hospital Corporation System and method for optical coherence imaging
JP4633423B2 (en) 2004-09-15 2011-02-16 株式会社トプコン Optical image measuring device
US7347553B2 (en) 2004-09-24 2008-03-25 Canon Kabushiki Kaisha Ophthalmic image sensing apparatus
JP4566685B2 (en) 2004-10-13 2010-10-20 株式会社トプコン Optical image measuring device and optical image measuring method
JP4494160B2 (en) 2004-10-14 2010-06-30 株式会社トプコン Optical image measuring device
JP2006116090A (en) 2004-10-21 2006-05-11 Nidek Co Ltd Fundus camera
US7445336B2 (en) 2004-10-21 2008-11-04 Nidek Co., Ltd. Fundus camera
US7252662B2 (en) 2004-11-02 2007-08-07 Lenticular Research Group Llc Apparatus and processes for preventing or delaying one or more symptoms of presbyopia
US7388672B2 (en) 2004-11-19 2008-06-17 Carl Ziess Meditec, Inc. High efficiency balanced detection interferometer
DE112005002902T5 (en) 2004-12-01 2007-10-18 Nidek Co., Ltd., Gamagori Ophthalmic device
JP4537192B2 (en) 2004-12-21 2010-09-01 キヤノン株式会社 Ophthalmic equipment
US8394084B2 (en) 2005-01-10 2013-03-12 Optimedica Corporation Apparatus for patterned plasma-mediated laser trephination of the lens capsule and three dimensional phaco-segmentation
US7336366B2 (en) 2005-01-20 2008-02-26 Duke University Methods and systems for reducing complex conjugate ambiguity in interferometric data
US7633627B2 (en) 2005-01-20 2009-12-15 Duke University Methods, systems and computer program products for characterizing structures based on interferometric phase data
EP2417903A1 (en) 2005-01-21 2012-02-15 Massachusetts Institute of Technology Methods and apparatus for optical coherence tomography scanning
US7365856B2 (en) 2005-01-21 2008-04-29 Carl Zeiss Meditec, Inc. Method of motion correction in optical coherence tomography imaging
US7342659B2 (en) 2005-01-21 2008-03-11 Carl Zeiss Meditec, Inc. Cross-dispersed spectrometer in a spectral domain optical coherence tomography system
US7330270B2 (en) 2005-01-21 2008-02-12 Carl Zeiss Meditec, Inc. Method to suppress artifacts in frequency-domain optical coherence tomography
WO2006080239A1 (en) 2005-01-31 2006-08-03 Olympus Corporation Image processing device, microscope system, and area specification program
US7390089B2 (en) 2005-02-25 2008-06-24 20/10 Perfect Vision Optische Geraete Gmbh Device and method for aligning an eye with a surgical laser
JP4837300B2 (en) 2005-03-24 2011-12-14 株式会社トプコン Optical image measuring device
US7665467B2 (en) 2005-04-26 2010-02-23 Biolase Technology, Inc. Methods for treating eye conditions
US7207983B2 (en) 2005-04-29 2007-04-24 University Of Florida Research Foundation, Inc. System and method for real-time feedback of ablation rate during laser refractive surgery
EP1913364B1 (en) 2005-07-28 2013-04-10 Bioptigen, Inc. Optical coherence imaging system having a reduced effective linewidth
GB2429522A (en) 2005-08-26 2007-02-28 Univ Kent Canterbury Optical mapping apparatus
US10488606B2 (en) 2005-09-19 2019-11-26 Topcon Medical Laser Systems, Inc. Optical switch and method for treatment of tissue
US20070129775A1 (en) 2005-09-19 2007-06-07 Mordaunt David H System and method for generating treatment patterns
US7400410B2 (en) 2005-10-05 2008-07-15 Carl Zeiss Meditec, Inc. Optical coherence tomography for eye-length measurement
US10524656B2 (en) 2005-10-28 2020-01-07 Topcon Medical Laser Systems Inc. Photomedical treatment system and method with a virtual aiming device
US20070121069A1 (en) 2005-11-16 2007-05-31 Andersen Dan E Multiple spot photomedical treatment using a laser indirect ophthalmoscope
US7593559B2 (en) 2005-11-18 2009-09-22 Duke University Method and system of coregistrating optical coherence tomography (OCT) with other clinical tests
JP4837982B2 (en) 2005-11-30 2011-12-14 株式会社ニデック Ophthalmic equipment
US9681985B2 (en) 2005-12-01 2017-06-20 Topcon Medical Laser Systems, Inc. System and method for minimally traumatic ophthalmic photomedicine
US7599591B2 (en) 2006-01-12 2009-10-06 Optimedica Corporation Optical delivery systems and methods of providing adjustable beam diameter, spot size and/or spot shape
EP1994361B1 (en) 2006-01-19 2016-07-27 Optovue, Inc. A fourier-domain optical coherence tomography imager
US20070173791A1 (en) 2006-01-20 2007-07-26 Intralase Corp. System for ophthalmic laser surgery
US10842675B2 (en) 2006-01-20 2020-11-24 Lensar, Inc. System and method for treating the structure of the human lens with a laser
US8262646B2 (en) 2006-01-20 2012-09-11 Lensar, Inc. System and method for providing the shaped structural weakening of the human lens with a laser
US9889043B2 (en) 2006-01-20 2018-02-13 Lensar, Inc. System and apparatus for delivering a laser beam to the lens of an eye
US9545338B2 (en) 2006-01-20 2017-01-17 Lensar, Llc. System and method for improving the accommodative amplitude and increasing the refractive power of the human lens with a laser
WO2007084694A2 (en) 2006-01-20 2007-07-26 Lensar, Inc. System and apparatus for delivering a laser beam to the lens of an eye
US20070219541A1 (en) 2006-03-14 2007-09-20 Intralase Corp. System and method for ophthalmic laser surgery on a cornea
US7768652B2 (en) 2006-03-16 2010-08-03 Carl Zeiss Meditec, Inc. Methods for mapping tissue with optical coherence tomography data
JP4864516B2 (en) 2006-04-07 2012-02-01 株式会社トプコン Ophthalmic equipment
HUE031948T2 (en) 2006-04-11 2017-08-28 Cognoptix Inc Ocular imaging
US8771261B2 (en) 2006-04-28 2014-07-08 Topcon Medical Laser Systems, Inc. Dynamic optical surgical system utilizing a fixed relationship between target tissue visualization and beam delivery
WO2007130411A2 (en) 2006-05-01 2007-11-15 Physical Sciences, Inc. Hybrid spectral domain optical coherence tomography line scanning laser ophthalmoscope
US20070282313A1 (en) 2006-06-01 2007-12-06 University Of Southern California Method and apparatus to guide laser corneal surgery with optical measurement
US7488930B2 (en) 2006-06-02 2009-02-10 Medeikon Corporation Multi-channel low coherence interferometer
US20070291277A1 (en) 2006-06-20 2007-12-20 Everett Matthew J Spectral domain optical coherence tomography system
US7452077B2 (en) 2006-08-29 2008-11-18 Carl Zeiss Meditec, Inc. Image adjustment derived from optical imaging measurement data
US8223143B2 (en) 2006-10-27 2012-07-17 Carl Zeiss Meditec, Inc. User interface for efficiently displaying relevant OCT imaging data
US8025403B2 (en) 2007-02-23 2011-09-27 Mimo Ag Ophthalmologic apparatus for imaging an eye by optical coherence tomography
US20090012507A1 (en) * 2007-03-13 2009-01-08 William Culbertson Method for patterned plasma-mediated modification of the crystalline lens
US8568393B2 (en) 2007-03-13 2013-10-29 Topcon Medical Laser Systems, Inc. Computer guided patterned laser trabeculoplasty
RU2378989C2 (en) * 2007-03-16 2010-01-20 Михаил Владимирович Кутушов Method of diagnostics by means of ultrasonic, sonic and electromagnetic waves
JP4896794B2 (en) 2007-03-30 2012-03-14 株式会社トプコン Optical image measuring apparatus, program for controlling the same, and optical image measuring method
US7575322B2 (en) 2007-05-11 2009-08-18 Amo Development Llc. Auto-alignment and auto-focus system and method
US9456925B2 (en) 2007-09-06 2016-10-04 Alcon Lensx, Inc. Photodisruptive laser treatment of the crystalline lens
ES2673575T3 (en) 2007-09-06 2018-06-22 Alcon Lensx, Inc. Precise fixation of surgical photo-disruption objective
US20100324543A1 (en) 2007-09-18 2010-12-23 Kurtz Ronald M Method And Apparatus For Integrating Cataract Surgery With Glaucoma Or Astigmatism Surgery
US8409182B2 (en) 2007-09-28 2013-04-02 Eos Holdings, Llc Laser-assisted thermal separation of tissue
JP4933413B2 (en) 2007-12-11 2012-05-16 株式会社トーメーコーポレーション Anterior segment optical coherence tomography apparatus and anterior segment optical coherence tomography method
US8230866B2 (en) 2007-12-13 2012-07-31 Carl Zeiss Meditec Ag Systems and methods for treating glaucoma and systems and methods for imaging a portion of an eye
US7792249B2 (en) 2007-12-23 2010-09-07 Oraya Therapeutics, Inc. Methods and devices for detecting, controlling, and predicting radiation delivery
US7878651B2 (en) 2007-12-26 2011-02-01 Carl Zeiss Meditec, Inc. Refractive prescription using optical coherence tomography
PL3363415T3 (en) 2008-01-09 2020-03-31 Alcon Lensx, Inc. Curved photodisruptive laser fragmentation of tissue
WO2009131701A2 (en) 2008-04-24 2009-10-29 Bioptigen, Inc. Optical coherence tomography (oct) imaging systems having adaptable lens systems and related methods and computer program products
US7898712B2 (en) 2008-06-27 2011-03-01 Lockheed Martin Corporation Risley integrated steering module
JP5255524B2 (en) 2008-07-04 2013-08-07 株式会社ニデック Optical tomographic imaging device, optical tomographic image processing device.
US20100022996A1 (en) 2008-07-25 2010-01-28 Frey Rudolph W Method and system for creating a bubble shield for laser lens procedures
US8480659B2 (en) 2008-07-25 2013-07-09 Lensar, Inc. Method and system for removal and replacement of lens material from the lens of an eye
US8500723B2 (en) 2008-07-25 2013-08-06 Lensar, Inc. Liquid filled index matching device for ophthalmic laser procedures
US9119565B2 (en) * 2009-02-19 2015-09-01 Alcon Research, Ltd. Intraocular lens alignment
US8240853B2 (en) 2009-05-01 2012-08-14 Bioptigen, Inc. Systems for imaging structures of a subject and related methods
CA2769097A1 (en) 2009-07-24 2011-01-27 Lensar, Inc. System and method for performing ladar assisted procedures on the lens of an eye
US9492322B2 (en) 2009-11-16 2016-11-15 Alcon Lensx, Inc. Imaging surgical target tissue by nonlinear scanning
US8403481B2 (en) 2010-01-20 2013-03-26 Duke University Methods, systems and computer program products for distributed scanning for motion artifact reduction in optical coherence tomography
US9278028B2 (en) 2010-02-08 2016-03-08 Optimedica Corporation System and method for plasma-mediated modification of tissue
US8414564B2 (en) 2010-02-18 2013-04-09 Alcon Lensx, Inc. Optical coherence tomographic system for ophthalmic surgery
US8845624B2 (en) 2010-06-25 2014-09-30 Alcon LexSx, Inc. Adaptive patient interface

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
None

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