Having Spurious Reflection Blocking Patents (Class 351/207)
  • Publication number: 20110234977
    Abstract: The present invention is a slit lamp mounted eye imaging, a slit lamp integrated, a handheld, OCT integrated, or attached to a separate chinrest-joystick assembly apparatus and method for producing a wide field and/or magnified views of the posterior or the anterior segments of an eye through an undilated or dilated pupil. The apparatus images sections and focal planes and utilizes an illumination system that uses one or more LEDs, shifting optical elements, flipping masks, and/or aperture stops where the light can be delivered into the optical system on optical axis or off axis from center of optical system and return imaging path from the eye, creating artifacts in different locations on the eye image. Image processing is employed to detect and eliminate artifacts and masks from images. The apparatus can be used in combination with an OCT, microscope and can be disposed in a hand-held housing for hand-held use.
    Type: Application
    Filed: March 22, 2011
    Publication date: September 29, 2011
    Inventor: Steven Roger Verdooner
  • Publication number: 20110176111
    Abstract: An ophthalmic photographing apparatus includes: an interference optical system including a splitter that splits light, emitted from a measurement light source, into measurement light and reference light, and synthesizing the measurement light reflected on an eye with the reference light to guide the synthesized light to a detector; a driving part that moves an optical member arranged in the optical path to adjust an optical-path difference between the measurement light and the reference light; an image obtaining part that obtains a tomographic image of a fundus or an anterior segment based on a light receiving signal output from the detector; and a driving control unit that controls driving of the driving part to locate the optical member in a predetermined position corresponding to either a photographing mode for photographing the tomographic image of the fundus or a photographing mode for photographing the tomographic image of the anterior segment.
    Type: Application
    Filed: January 20, 2011
    Publication date: July 21, 2011
    Applicant: NIDEK CO., LTD.
    Inventors: Seiji TAKI, Yukio ABE, Hiroyoshi NAKANISHI, Toshio MURATA, Yasuhiro FURUUCHI
  • Publication number: 20100283971
    Abstract: A monocular image of a fundus of an eye under examination is captured via a photographic stop for monocular photography, and two stereographically viewed images are captured with a parallax via two photographic stops for stereographic photography that are decentered from a photographic optical axis. Defocused images are captured in the stereographic photography due to the deviation of the photographic stops from the optical axis. A corrective lens is inserted into the photographic optical path in order to correct the defocus in the stereographic photography. This makes it possible to readily correct defocus generated by deviation of the photographic stops from the photographic optical axis even when switching between monocular and stereographic photography modes.
    Type: Application
    Filed: July 14, 2010
    Publication date: November 11, 2010
    Inventor: Takayoshi Suzuki
  • Publication number: 20100128221
    Abstract: A portable, lightweight digital imaging device uses a slit scanning arrangement to obtain an image of the eye, in particular the retina.
    Type: Application
    Filed: December 21, 2009
    Publication date: May 27, 2010
    Applicant: Indiana University Research and Technology Corporation
    Inventors: Matthew S. Muller, Ann E. Elsner, Benno L. Petrig
  • Publication number: 20100014052
    Abstract: The invention is directed to an optical system for a fundus camera for reflection-free opthalmoscopy having a beam path with refractive and reflective optical elements which are used substantially in common for illumination and observation or recording. An imaging mirror system substantially comprising a plurality of reflecting optical elements in the form of mirrors and is provided for illuminating and imaging the fundus. At least one optical element, for example, mirror, is formed as a freeform mirror with an imaging, reflecting freeform surface. The optical elements are arranged in a housing in a precisely defined position and attitude relative to one another in such a way that an imaging of the reflecting surfaces of the optical elements on the image of the imaged retina is prevented within a wide diopter range of the patient's eye to be examined.
    Type: Application
    Filed: December 18, 2007
    Publication date: January 21, 2010
    Inventors: Ingo Koschmieder, Manfred Dick, Detlef Biernat, Jan Buchheister, Lothar Mueller
  • Publication number: 20100007849
    Abstract: An opthalmoscope for examining a patient's eye includes an illumination device for generating an illumination beam Illumination imaging optics image the illumination beam onto the eye, and a scanning device scans the illumination beam over the eye. The opthalmoscope also includes an observation device and observation imaging optics for imaging an observation beam generated by reflection of the illumination beam from the eye onto the observation device. An electronic shutter excludes stray light from the observation beam. The observation device comprises an electronic sensor with an array of photosensitive pixels that can respectively be activated and/or read out in rows, and the scanning device includes an electronic drive circuit for reading out at least one pixel row of the sensor.
    Type: Application
    Filed: July 9, 2007
    Publication date: January 14, 2010
    Applicant: OD-OS GmbH
    Inventors: Ben Liesfeld, Winfried Teiwes, Michael Huppertz, Kay-Uwe Amthor
  • Publication number: 20090180072
    Abstract: A monocular image of a fundus of an eye under examination is captured via a photographic stop for monocular photography, and two stereographically viewed images are captured with a parallax via two photographic stops for stereographic photography that are decentered from a photographic optical axis. Defocused images are captured in the stereographic photography due to the deviation of the photographic stops from the optical axis. A corrective lens is inserted into the photographic optical path in order to correct the defocus in the stereographic photography. This makes it possible to readily correct defocus generated by deviation of the photographic stops from the photographic optical axis even when switching between monocular and stereographic photography modes.
    Type: Application
    Filed: June 25, 2008
    Publication date: July 16, 2009
    Inventor: Takayoshi Suzuki
  • Patent number: 7515054
    Abstract: Biosensor, communicator, and/or controller apparatus, systems, and methods are provided for monitoring movement of a person's eye. The apparatus includes a device configured to be worn on a user's head, a light source for directing light towards one or both eyes of the user, one or more image guides on the device for viewing one or both eyes of the user, and one or more cameras carried on the device and coupled to the image guides for acquiring images of the eyes and/or the user's surroundings. The apparatus may include a cable and/or a transmitter for transmitting image data from the camera to a remote location, e.g., to processor and/or display for analyzing and/or displaying the image data. A system including the apparatus may be used to monitor one or more oculometric parameters, e.g., pupillary response, and/or to control a computer using the user's eyes instead of a mouse.
    Type: Grant
    Filed: April 1, 2005
    Date of Patent: April 7, 2009
    Inventor: William C. Torch
  • Publication number: 20080278686
    Abstract: The components of a fundus camera for observing an eye (11)—namely, an illumination device (1) to illuminate an image field of the eyeground (12) and an image recording device (14) onto which the eyeground (12) is projected by means of a projection device (10)—are positioned to be confocal. The illumination device (1) is so structured that a periodic light pattern is created against the eyeground (12) within the illuminated image field. Further, an offset medium is present to offset the pattern by less than one period. The image recording device (14) is connected to an evaluation unit (22) in order to combine at least three recordings illuminated with offset patterns into a single photograph. A single, unstructured, extremely sharply focused photograph of the eyeground (12) may thus be obtained.
    Type: Application
    Filed: April 28, 2008
    Publication date: November 13, 2008
    Inventors: Axel Kasper, John Robert Zinter
  • Patent number: 7445337
    Abstract: An area having a diameter in which a peripheral area of an eye fundus image is covered with a mask is displayed on a monitor. When a region which may be abnormal is found in the vicinity of a boundary between the mask and the eye fundus image during image viewing, the display area enlarging means is operated. Then, an aperture area of the mask is enlarged to expand a display area of the eye fundus image, so the eye fundus image including some flare is displayed on a wide area. Therefore, an abnormal state of the region can be recognized.
    Type: Grant
    Filed: September 28, 2005
    Date of Patent: November 4, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventor: Kyoji Sekiguchi
  • Publication number: 20080192203
    Abstract: A stripe pattern of known distance is imaged on the ocular fundus by the imaging unit for ophthalmological devices. This makes it possible to carry out absolute measurements of distances and objects at the ocular fundus with knowledge of the initial values serving as a basis. The imaging unit for ophthalmological devices, particularly fundus cameras, according to the invention comprises a device for generating and imaging any, but a known, stripe pattern or line pattern on the retina of an eye to be examined, a camera for recording the stripe pattern or line pattern on the retina, and an evaluating unit for determining the distances on the retina. The imaging unit is constructed in such a way that the stripe pattern or line pattern to be imaged is coupled into the beam path between the ophthalmological device and the eye to be examined. The use of an imaging unit of this kind as an accessory to ophthalmological devices also expands the possibilities for its use in measurements at the ocular fundus.
    Type: Application
    Filed: June 22, 2006
    Publication date: August 14, 2008
    Inventors: Detlef Biernat, Ingo Koschmieder, Bernhard Rassow, Thomas Mohr
  • Patent number: 7354153
    Abstract: A fundus camera capable of favorably obtaining a photographed fundus image and an observation fundus image, has an optical system having an objective lens and a diaphragm at a conjugate position with a pupil relative to the lens, for performing visible photographing and infrared observation via the lens and an aperture of the diaphragm, an optical system for illumination with visible and infrared light via the lens, a first plate, with a first black dot to cover an aperture image and at a conjugate position on an optical path with a position where a virtual image is formed relative to a lens surface reflecting the visible light, and a second plate, with a second black dot to cover an aperture image and in the vicinity of a conjugate position on the path with a position where a virtual image is formed relative to the surface reflecting the infrared light.
    Type: Grant
    Filed: February 23, 2005
    Date of Patent: April 8, 2008
    Assignee: Nidek Co., Ltd.
    Inventors: Akira Tawada, Setsuo Saito
  • Patent number: 7347548
    Abstract: Methods and systems are provided for measuring a retinal sublayer characteristic of an eye. A plurality of axial scans are performed over an area of the retina of the eye. Reflections are measured during the axial scans to determine a plurality of sets of reflection intensity values. A given set of reflection intensity values is associated with one of the plurality of axial scans. A progressive refinement boundary detection algorithm is performed using the plurality of sets of reflection intensity values to determine at least one boundary location associated with the retinal sublayer for each of the plurality of sets of reflection intensity values. The retinal sublayer characteristic is determined in response to the determined boundary locations.
    Type: Grant
    Filed: April 28, 2004
    Date of Patent: March 25, 2008
    Assignee: The Cleveland Clinic Foundation
    Inventors: David Huang, Ou Tan, Yan Li
  • Patent number: 7338167
    Abstract: A retinal imaging system includes a light source and optics which receive light from the light source and which transmit the light to produce a beam that is substantially convergent. The beam penetrates a lens of an eye and diverges following penetration of the lens to illuminate an area of a retina of the eye. An imaging device receives a reflection of light from the retina.
    Type: Grant
    Filed: December 10, 2003
    Date of Patent: March 4, 2008
    Assignee: Joslin Diabetes Center, Inc.
    Inventors: Joseph Zelvin, Sven-Erik Bursell
  • Patent number: 7333636
    Abstract: To determine the presence or absence of an aperture mask in a funduscopic image output by a fundus camera, and to combine the funduscopic image with an aperture mask image formed in an aperture mask-forming section so as to correspond to a determination result. When an aperture mask determination section 34 determines the absence of the aperture mask image in the funduscopic image and the necessity of the addition, the aperture mask-forming section 35 forms a necessary mask, and an aperture mask combine section 36 combines the funduscopic image with the aperture mask image.
    Type: Grant
    Filed: October 21, 2004
    Date of Patent: February 19, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventor: Kyoji Sekiguchi
  • Patent number: 7306336
    Abstract: An apparatus for observing a fundus of an eye of an examinee has an observation optical system having an image-pickup element which obtains a time-series fundus image, a display part which displays the obtained fundus image on its monitor as a moving image, a determination part which determines a standard fundus image based on the displayed image, a memory part which stores the determined image, a calculation part which digitizes the image based on a threshold luminance level to obtain a digitized image thereof, digitizes a present fundus image obtained after the determination of the standard image based on the threshold luminance level to obtain a digitized image thereof and compares the obtained digitized images two-dimensionally to obtain their positional difference, and a display control part for correcting a display position of the present fundus image based on the obtained positional difference to display the corrected image on the monitor.
    Type: Grant
    Filed: December 22, 2004
    Date of Patent: December 11, 2007
    Assignee: Nidek Co., Ltd.
    Inventors: Junichi Akita, Akihiro Fujishiro, Toshifumi Sumiya, Naoyuki Kondo
  • Patent number: 7252381
    Abstract: An ophthalmoscope has illuminating optics (10) for projecting a beam of light into an eye under examination and imaging optics (14) for creating an image of said eye for viewing by a user. The imaging optics comprises an objective lens system (16) and an eye piece lens system (20). Two corneal reflex stops (138 and 148) are positioned one on either side of the corneal image formed by the objective lens system. The stops block reflections from the cornea of the eye under examination over a range of distances of the ophthalmoscope from the eye. The use of the two corneal reflex stops results in the precise positioning of the ophthalmoscope relative to the eye under examination not being critical to the blocking of the corneal reflex.
    Type: Grant
    Filed: August 25, 2004
    Date of Patent: August 7, 2007
    Assignee: Keeler Limited
    Inventors: Clive Harrold Thomas Burrows, Kelvyn Church, Stephen Church, David Ernest Lane Freeman, James Robert Arnold Matthews
  • Patent number: 7241011
    Abstract: An apparatus (220) for obtaining a scanned image of an eye has a reference locator for pupil alignment apparatus along an optical axis. A pupil profiling apparatus for obtaining an outline of the pupil has a pupil profiling light source (176), a sensor (170) for detecting reflected light, and a control logic processor (104) for computing an outline of the pupil according to detected light. An illumination apparatus (112) for directing visible illumination into the eye has a spatial light modulator (125) for shaping an illumination beam according to the detected outline, a scanning element (229), and a camera (146) for obtaining the scanned image by sensing a portion of the reflected illumination.
    Type: Grant
    Filed: October 29, 2004
    Date of Patent: July 10, 2007
    Assignee: Carestream Health, Inc.
    Inventors: Seung-Ho Baek, Douglass L. Blanding, Rongguang Liang, Dale L. Tucker, Jeffery R. Hawver
  • Patent number: 7198367
    Abstract: A fundus imaging apparatus comprises: a beam emitter which simultaneously emits a first laser beam and a second laser beam having a different wavelength from the first beam; an irradiation optical system having a beam scanner which scans the emitted first and second beams in two dimensions on a fundus, the irradiation optical system being adapted to irradiate the emitted first and second beams onto the fundus; a first filter which intercepts the first and second beams reflected by the fundus and second fluorescence from the fundus by irradiation of the second beam and transmits first fluorescence from the fundus by irradiation of the first beam; a second filter which intercepts the first and second beams reflected by the fundus and the first fluorescence from the fundus and transmits the second fluorescence from the fundus; an imaging optical system having a photo-receiving element which receives the first fluorescence having passed through the first filter and the second fluorescence having passed through th
    Type: Grant
    Filed: March 1, 2006
    Date of Patent: April 3, 2007
    Assignee: Nidek Co., Ltd.
    Inventors: Junichi Akita, Naoyuki Kondo, Akihiro Fujishiro, Katsuyasu Mizuno
  • Patent number: 7174094
    Abstract: A system is provided for reflex-free coaxial illumination that includes an objective lens group having an optical axis. An illumination source is axially disposed from the objective lens. The illumination source provides at least one light beam. The light beam is directed across the optical axis through a peripheral section of the objective lens. The light beam form a continuous field of illumination at a subject. A reflex mask is disposed behind the illumination source.
    Type: Grant
    Filed: February 7, 2005
    Date of Patent: February 6, 2007
    Inventor: Peter Norman Steinkamp
  • Patent number: 7048379
    Abstract: An imaging system and method for imaging an object, where an objective lens directs light to the object, a coupling lens receives light reflected from a surface of the object and transmitted through the objective lens, and focuses the reflected light as an image of the object, and an annular light emitter arranged concentrically with an optical axis of the objective lens and the coupling lens emits to the objective lens the light directed to the object.
    Type: Grant
    Filed: March 17, 2004
    Date of Patent: May 23, 2006
    Assignee: The Arizona Board of Regents on behalf of the University of Arizona
    Inventors: Joseph Marion Miller, James Theodore Schwiegerling
  • Patent number: 6605081
    Abstract: Systems, methods and apparatus for generating images of portions of the patient's eye, such as the anterior surface of the cornea. The methods and apparatus of the present invention are particularly useful for directly imaging the profile of the ablated region of the cornea during or immediately following a laser ablation procedure, such as photorefractive keratometry (PRK), phototherapeutic keratectomy (PTK), laser in-situ keratomileusis (LASIK) or the like. These methods and apparatus allow the surgeon to precisely image the exterior edge of the eye to characterize the profile of ablated corneas and to determine the spatial variance of tissue ablation rates during the surgical procedures. Methods and apparatus are also provided for generating one or more images depicting the profile of the ablated region of the cornea. The profile is registered with a pre-ablation profile to provide feedback regarding the true ablation properties of the eye.
    Type: Grant
    Filed: May 5, 2000
    Date of Patent: August 12, 2003
    Assignee: Visx, Incorporated
    Inventors: John K. Shimmick, Stephen J. Hinkson, Charles R. Munnerlyn
  • Patent number: 6490365
    Abstract: An eye image pickup device includes an object lens; an image pickup element, such as a CCD serving as an image pickup unit; a light shielding portion; and a light guide unit. The light shielding portion shielding one part of the pickup light path is coaxially positioned along a light axis of an optical image pickup system. The light guide unit guides visible light on the route of the guide light path leading to the object lens. A cross section of the guided visible light is similar to that of the light shielding portion, and the center of the visible light is coincident with the light axis. The cross-sectional area of the visible light is set substantially equal to or slightly larger than the effective cross sectional area of the light shielding portion with respect to the optical image pickup system along the light path.
    Type: Grant
    Filed: July 12, 2001
    Date of Patent: December 3, 2002
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Syuichi Horiguchi, Takayoshi Hasegawa
  • Publication number: 20020036750
    Abstract: A system and method for eye examination by scanning light scattered from an area of the retina and projecting light into the eye includes a scanner, a receiver unit, and a projection unit. The scanner is constructed and arranged to scan an area on the retina. The receiver unit is optically coupled to the scanner and constructed and arranged to capture light scattered back from the area of the retina. The projection unit is constructed to generate and optically couple a light configuration to the scanner for delivering the light configuration into the eye relative to the area of the retina, wherein the scanner, the receiver unit and the projection unit are cooperatively designed to analyse a patient's sight.
    Type: Application
    Filed: September 22, 2001
    Publication date: March 28, 2002
    Inventors: Heinrich A. Eberl, Roland H. C. Eberl, Hans Brandl
  • Patent number: 6088470
    Abstract: A reliable method and apparatus for illuminating and imaging eyes uses multiple light sources producing multiple images of a subject each created under illumination by different illuminators. A composite image of the subject is formed by selecting pixels based upon their gray scale values or using pyramid image processing. A composite image can be created which is free of bright spots commonly caused by reflection of illumination from eyeglasses that may be worn by a subject or for which is free of dark shadows or which is free of both bright spots and dark shadows.
    Type: Grant
    Filed: January 27, 1998
    Date of Patent: July 11, 2000
    Assignees: Sensar, Inc., Sarnoff Corporation
    Inventors: Theodore A. Camus, Marcus Salganicoff, Thomas A. Chmielewski, Jr., Keith James Hanna
  • Patent number: 6059773
    Abstract: A technique for evaluating the topography of a cornea in which a virtual object of a keratoscope pattern isured. The topography system includes a structured light source to create the keratoscope pattern or another diagnostic pattern, an optical assembly to focus the created pattern upon or behind the cornea, and for capturing the image reflected off the patient's eye and directing the reflected image toward an imaging system for processing. Light emitted by the light source is preferably not in the visible range, to minimize discomfort to the patient. Since the topography is evaluated with a projected virtual image, there is no nose or brow shadow, thereby allowing better corneal coverage. The optical system includes an aperture stop which is preferably conjugate with a point behind the corneal surface approximating the center of a normal cornea. Thus, wide angle capture is achieved as reflected rays reaching the imaging system appear as if they originated at the center of the cornea.
    Type: Grant
    Filed: August 4, 1997
    Date of Patent: May 9, 2000
    Assignee: VisionRx.Com, Inc.
    Inventors: Robert K. Maloney, Jeffrey L. Stewart, Bruce E. Truax
  • Patent number: 5873832
    Abstract: A technique for evaluating the topography of a cornea, which utilizes a virtual image of a keratoscope pattern. The topography system includes a structured light source to create the keratoscope pattern or another diagnostic pattern, an optical assembly to focus the created pattern upon the cornea, and for capturing the image reflected off the patient's eye and directing the reflected image towards an imaging system for processing. Light emitted by the light source is preferably not in the visible range, to minimize discomfort to the patient. Since the topography is evaluated with a projected virtual image, there is no nose or brow shadow, thereby alowing better corneal coverage. The optical system includes an aperture stop which is preferably conjugate with a point behind the corneal surface approximating the center of a normal cornea. Thus, wide angle capture is achieved as reflected rays reaching the imaging system appear as if they originated at the center of the cornea.
    Type: Grant
    Filed: August 12, 1996
    Date of Patent: February 23, 1999
    Assignee: Xeyex Corporation
    Inventors: Robert K. Maloney, Jeffrey L. Stewart
  • Patent number: 5506634
    Abstract: Apparatus for illuminating the fundus of an eye with a scanned sample beam of radiation. An embodiment of the present invention is an optical system which includes three, separated radiation path systems--a tilted illumination path system, a decentered observation path system, and an optical path system--which are combined by a beamsplitter into an ocular lens. In accordance with the present invention, an illuminating path provided by the illumination path system and an optical beam path provided by the optical beam path system are obliquely oriented with respect to the optical axis of the ocular lens.
    Type: Grant
    Filed: July 5, 1994
    Date of Patent: April 9, 1996
    Assignee: Carl Zeiss, Inc.
    Inventors: Jay Wei, Thomas Hellmuth
  • Patent number: 5300964
    Abstract: A fundus camera includes a light source for observation, and an illiminating optical system having a predetermined illiminating optical axis. The light source for observation illiminates a fundus of an eye via the illiminating optical system. The camera further includes an observation optical system disposed so as to be able to observe the fundus illiminated by the light source for observation, a photographing light source for illiminating the fundus during a photographing operation and disposed on the illiminating optical axis of the illiminating optical system, a photographing system for photographing the fundus illuminated by the photographing light source, and a reflecting member disposed between the light source for observation and the photographing light source on the illuminating optical axis so as to reflect light from the photographing light source in the direction of the fundus during illumination by the photographing light source.
    Type: Grant
    Filed: April 9, 1992
    Date of Patent: April 5, 1994
    Assignee: Canon Kabushiki Kaisha
    Inventor: Kazunobu Kobayashi
  • Patent number: 5250966
    Abstract: An ophthalmic photographing apparatus comprises an illumination optical system for illuminating an eye to be tested, a viewing optical system having a variable magnification optical system for viewing the illuminated eye to be tested, and a photographing device detachably mounted on the viewing optical system. A position change of a predetermined part due to the change of magnification of the variable magnification optical system is measured to produce a signal representing the displacement. The signal representing the magnification of the variable magnification optical system is used to control an intensity of a flash light.
    Type: Grant
    Filed: March 13, 1992
    Date of Patent: October 5, 1993
    Assignee: Nikon Corporation
    Inventors: Haruo Oda, Eiji Satake, Ken Tomioka
  • Patent number: 5247318
    Abstract: The fundus camera of this invention for taking photographs by fluorescence comprises an exciter filter 7 in an illuminating optical system 1, and a barrier filter 16 in a photographic optical system 2. A member 11 for eliminating harmful reflected light from an objective lens 13 is also provided in the illuminating optical system 1. This member 11 for eliminating harmful reflected light comprises dark spots 21, 22, which transmit light below a lower wavelength limit, and cut out light above the lower wavelength limit, of the barrier filter 16.
    Type: Grant
    Filed: December 10, 1991
    Date of Patent: September 21, 1993
    Assignee: Kabushiki Kaisha Topcon
    Inventor: Haruhiko Suzuki
  • Patent number: 5118179
    Abstract: An ophthalmological photographing instrument has photographing means for imaging the fundus of an eye to be tested every time a photographing switch is actuated, and a barrier filter to be inserted into a photographing optical path when a fluorescence photography is performed. It also has a light receiving sensor for receiving fluorescence emitted from the eye fundus and control means for inserting the barrier filter into the taking optical path every time the taking switch is actuated when a light receiving signal output from the eye fundus becomes either larger or smaller than a predetermined value.
    Type: Grant
    Filed: April 26, 1990
    Date of Patent: June 2, 1992
    Assignee: Kabushiki Kaisha Topcon
    Inventors: Eiichi Sano, Hideaki Tokoro
  • Patent number: 4715704
    Abstract: A microscope for examinations and surgical operations on the eye, having provision for projecting onto the eye a hollow beam of illuminating light, the beam having a dark center portion of the same diameter as the pupil of the eye. Thus the surgeon may have adequate illumination of the external surface of the eye around the pupil, without projecting light which might be disturbing or damaging to the patient, onto the retina or fundus of the eye. The light blocking structure, in the form of an annular diaphragm with a light-impervious central portion, is located in the illuminating light beam at a point which is conjugated with respect to the object plane, i.e., the plane of the pupil of the eye being examined. The diaphragm may be moved aside to an ineffective position when required.
    Type: Grant
    Filed: October 21, 1986
    Date of Patent: December 29, 1987
    Assignee: Carl-Zeiss-Stiftung
    Inventors: Klaus Biber, Gerhard Unold
  • Patent number: 4449798
    Abstract: In an eye fundus observation apparatus wherein light-intercepting members for eliminating flare are provided at predetermined positions in an illumination optical path which are substantially conjugate with the cornea and the front surface of the crystalline lens of an eye being examined in a condition in which the apparatus is focused to the fundus of the eye, an observation opening is formed at a position substantially conjugate with a position between the cornea and the front surface of the crystalline lens of the eye whereat the magnification of the reflected image on the rear surface of the crystalline lens is approximately one-to-one magnification in a condition in which the apparatus is focused to the fundus of the eye.
    Type: Grant
    Filed: March 2, 1982
    Date of Patent: May 22, 1984
    Assignee: Nippon Kogaku K.K.
    Inventor: Masao Nohda
  • Patent number: 4443075
    Abstract: A stabilized visual system for directing a beam of energy, such as a laser beam, to a specific selected location in an eye and maintaining the beam in the selected location regardless of eye movements. The system employs a fundus illumination and monitoring device which illuminates the fundus of an eye and allows an observer simultaneously to observe the illuminated fundus, an eye tracker which continuously measures the position and changes in position of the illuminated eye and produces electrical signals in response to the changes in position of the eye, and an input beam stabilizer which directs a beam of electromagnetic energy to a selected location in the eye. Servomotor driven optical elements (e.g., a pair of mirrors) are positioned in the path of the beam of electromagnetic energy and are connected to receive and be driven by the electrical signals produced by the eye tracker so that the electromagnetic beam is maintained at the specific selected location in the eye even though the eye moves.
    Type: Grant
    Filed: June 26, 1981
    Date of Patent: April 17, 1984
    Assignee: SRI International
    Inventor: Hewitt D. Crane
  • Patent number: 4439024
    Abstract: In the disclosed eye examining instrument, an eye inspection system forms a first optical path and an eye illuminating system forms a second optical path which begins outside the first optical path and then extends along the optical axis of the first optical path near the eye. A shading member in the optical path of the illuminating member is substantially conjugate with the pupil of the eye and cooperates with variable limiting means that vary the shading. In one embodiment, the variable limiting means is a second shading member movable toward and away from the first shading member along the optical path of the illuminating system and conjugate with an interior portion of the eye so as selectively to block out portions of the unshaded light reaching the eye fundus.
    Type: Grant
    Filed: April 23, 1979
    Date of Patent: March 27, 1984
    Assignee: Canon Kabushiki Kaisha
    Inventor: Yuji Ito
  • Patent number: 4423932
    Abstract: An eye fundus observing and photographing optical system has an objective lens including a main positive lens component and at least one positive lens component provided at that side of the main positive lens component which is adjacent to an eye to be examined, and an illuminating optical system including an apertured mirror disposed obliquely with respect to the optical axis of the objective lens to supply an illuminating light to the fundus of the eye through the objective lens.
    Type: Grant
    Filed: December 8, 1980
    Date of Patent: January 3, 1984
    Assignee: Nippon Kogaku K.K.
    Inventor: Fumio Takahashi
  • Patent number: 4422736
    Abstract: An eye fundus camera including an illuminating system having two apertured masks. One of the masks has a pair of coaxial ring-shaped slits and located with respect to the objective lens in conjugate with the cornea of the patient's eye, whereas the other has a ring-shaped slit in conjugate with the iris of the eye. The arrangement is effective to provide an increased field angle with a substantially uniform illumination without having adverse effects of harmful reflections.
    Type: Grant
    Filed: March 18, 1981
    Date of Patent: December 27, 1983
    Assignee: Tokyo Kogaku Kikai Kabushiki Kaisha
    Inventor: Kazuo Nunokawa