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US5585873A Expired / Lapsed US ⏱️ 0.0 years remaining

Automated hand-held keratometer

Assignee: Alcon Vision LLC
•
Filing: 1991-10-11
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Granted: 1996-12-17
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Expires: 2011-10-11
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Abstract

Abstract An automated portable keratometer includes a hand held housing and is battery powered. A projection system projects collimated light sources at equal converging angles to an optical axis which extends outside the housing. A camera, including an imaging device, and telocentric objective lens are aligned along the optical axis in the housing. The projection system projects a known pattern of collimated light sources onto a patient's eye. The reflected images of these light sources is captured by the camera and imaging device. Derivation of the distances between certain reflected images can be converted by known algorithms into radii of curvature of the eye. Alignment leveling, and other features can be included with the keratometer. The device can also be used to measure other curved surfaces.

Inventors

  • 👤 Tadmor Shalon
  • 👤 Marvin L. Pund

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 15:49
CPC Classifications
A; A61; A61B; A61B3/00; A61B3/10; A61B3/107

Claims Analysis

Total Claims: 29
Claim 1
Independent Claim 97 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.
Claim 2
Dependent Claim 97 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.
Claim 3
Dependent Claim 27 words
The keratometer means of claim 1 wherein the projector means comprises a plurality of projection assemblies each including a light source, a pin hole, and a lens.
Claim 4
Dependent Claim 22 words
The keratometer means of claim 2 wherein the projection assemblies are positioned circumferentially around an optical axis and angled towards that axis.
Claim 5
Dependent Claim 22 words
The keratometer means of claim 3 wherein each projector assembly is angled at the same angle with respect to the optical axis.
Claim 6
Dependent Claim 16 words
The keratometer means of claim 2 wherein each projection assembly includes a plurality of light sources.
Claim 7
Dependent Claim 30 words
The keratometer means of claim 5 wherein the plurality of light sources are aligned generally along a plane which is normal to an axis through the pin hole and lens.
Claim 8
Dependent Claim 125 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; the imaging means comprises an area imager consisting of a matrix of pixels, each pixels producing a signal proportional to the intensity of light received at the pixel; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.
Claim 9
Dependent Claim 125 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; the imaging means comprises an area imager consisting of a matrix of pixels, each pixels producing a signal proportional to the intensity of light received at the pixel; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.
Claim 10
Dependent Claim 140 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; an alignment means for aligning the projector means with respect to the patient's eye, the alignment means including an eye piece for allowing a user of the keratometer means to view the patient's eye and the collimated lights sources from the projector means; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.
Claim 11
Dependent Claim 140 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; an alignment means for aligning the projector means with respect to the patient's eye, the alignment means including an eye piece for allowing a user of the keratometer means to view the patient's eye and the collimated lights sources from the projector means; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.
Claim 12
Dependent Claim 112 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; a fixation means for providing the patient with a light source upon which to fixate; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.
Claim 13
Dependent Claim 112 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; a fixation means for providing the patient with a light source upon which to fixate; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.
Claim 14
Dependent Claim 157 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; and further comprising a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction, the leveling means including a chamber at least partially filled with a fluid and a back-lighting source, the image of the fluid in the chamber being captured by the imaging means and the processing means for analyzing whether the top level of the fluid is correctly positioned with respect to a frame of reference of the imaging means.
Claim 15
Dependent Claim 157 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; and further comprising a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction, the leveling means including a chamber at least partially filled with a fluid and a back-lighting source, the image of the fluid in the chamber being captured by the imaging means and the processing means for analyzing whether the top level of the fluid is correctly positioned with respect to a frame of reference of the imaging means.
Claim 16
Dependent Claim 124 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; a ring of one or more light sources which project a ring of light onto the patient's eye to allow testing of the nature of the eye; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.
Claim 17
Dependent Claim 124 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; a ring of one or more light sources which project a ring of light onto the patient's eye to allow testing of the nature of the eye; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.
Claim 18
Dependent Claim 114 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; further comprising a display means in the housing means for displaying information related to the keratometric readings; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.
Claim 19
Dependent Claim 114 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; further comprising a display means in the housing means for displaying information related to the keratometric readings; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.
Claim 20
Dependent Claim 109 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; control means for selecting operational modes and functions for the keratometer means; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.
Claim 21
Dependent Claim 109 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; control means for selecting operational modes and functions for the keratometer means; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.
Claim 22
Dependent Claim 114 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; further comprising battery power means for providing power to the projector means, imaging means, and processing means; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.
Claim 23
Dependent Claim 114 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; further comprising battery power means for providing power to the projector means, imaging means, and processing means; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.
Claim 24
Dependent Claim 118 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; means for connecting a battery within the keratometer means with a recharging means such that the battery may be periodically recharged; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.
Claim 25
Dependent Claim 118 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; means for connecting a battery within the keratometer means with a recharging means such that the battery may be periodically recharged; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.
Claim 26
Dependent Claim 105 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; and the imaging means comprises a CCD camera; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.
Claim 27
Dependent Claim 105 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; and the imaging means comprises a CCD camera; processing means in the housing means for analyzing the recorded received images to derive keratometric readings of the patient's eye; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.
Claim 28
Dependent Claim 144 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; and processing means in the housing for analyzing the recorded received images to derive keratometric readings of the patient's eye; processing means in the housing for analyzing the recorded received images to derive keratometric readings of the patient's eye; an alignment means for providing a user with a light source indicating a point at which the patient's eye should be positioned for correct up/down and left/right alignment; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.
Claim 29
Dependent Claim 144 words
A keratometer means comprising: a portable housing means including a hand grip section; a projector means in the housing means for projecting a pattern of collimated light sources onto a patient's eye; an imaging means in the housing means for capturing and recording received images, including reflection of the pattern of collimated light sources from the patient's eye; and processing means in the housing for analyzing the recorded received images to derive keratometric readings of the patient's eye; processing means in the housing for analyzing the recorded received images to derive keratometric readings of the patient's eye; an alignment means for providing a user with a light source indicating a point at which the patient's eye should be positioned for correct up/down and left/right alignment; and a leveling means for automatically confirming whether the housing means is leveled with respect to a predetermined direction.

References Cited (Backward Citations)

US3248162A Cited
US1006825A Cited
US1721208A Cited
US1750931A Cited
US2174308A Cited
US3108523A Cited
US3141396A Cited
US3432227A Cited
US3169459A Cited
US3264932A Cited
US3416855A Cited
US3404936A Cited
US3487069A Cited
US3544220A Cited
US3442579A Cited
US3486812A Cited
US3453437A Cited
US3542458A Cited
US3536384A Cited
US3552837A Cited
US3598478A Cited
US3572909A Cited
US3634003A Cited
US3669530A Cited
US3664631A Cited
USRE27475E Cited
US3797921A Cited
US3883233A Cited
US3871772A Cited
US3879113A Cited
US3932030A Cited
US4021102A Cited
US4196980A Cited
US3972602A Cited
US3969019A Cited
US4019813A Cited
US4315672A Cited
US4159867A Cited
US4172639A Cited
US4220401A Cited
US4157859A Cited
US4165744A Cited
US4293198A Cited
US4162828A Cited
US4180323A Cited
US4293199A Cited
US4312574A Cited
US4199816A Cited
US4372655A Cited
US4390255A Cited
US4256385A Cited
US4373787A Cited
US4367019A Cited
US4304468A Cited
US4353625A Cited
US4410243A Cited
US4421391A Cited
US4407572A Cited
US4420228A Cited
US4355871A Cited
US4444476A Cited
US4429960A Cited
US4396261A Cited
US4572628A Cited
US4453808A Cited
DE3125494A1 Cited
US4660946A Cited
US4588270A Cited
US4440477A Cited
US4606623A Cited
US4491398A Cited
US4730917A Cited
US4637700A Cited
US4569576A Cited
US4609287A Cited
US4710003A Cited
US4540254A Cited
US4660945A Cited
US4533221A Cited
US4597648A Cited
US4692003A Cited
US4697895A Cited
US4662730A Cited
US4761071A Cited
US4761070A Cited
US4705037A Cited
US4755043A Cited
US4772114A Cited
US4768875A Cited
US4848896A Cited
US4772115A Cited
US4779973A Cited
US4903706A Cited
US4828381A Cited
US4863260A Cited
US5011276A Cited
US4881807A Cited
US5157427A Cited
US5189449A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1999-12-17 2000-06-17 2000-12-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2003-12-17 2004-06-17 2004-12-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2007-12-17 2008-06-17 2008-12-17 $7700.00 Window Closed / Lapsed

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