Method and apparatus for measuring vertical and horizontal pupillary decentration

• US 5,691,799 A
• Filed: 08/21/1996
• Issued: 11/25/1997
• Est. Priority Date: 01/31/1996
• Status: Expired due to Fees

• Current Assignee: Narayanan Ramachandran
• Original Assignee: Narayanan Ramachandran
• Inventors: Ramachandran, Narayanan
• Primary Examiner(s): MAI, HUY KIM
• Application Number:
  US08/700,987
• Time in Patent Office: 461 Days
• Field of Search: 351/200, 351/204, 351/205, 351/245, 33/200
• US Class Current: 351/204
• CPC Class Codes: A61B 3/11 for measuring interpupillary distance or diameter of pupils
• CPC Class Codes: A61F 2009/0043 by supporting the instrument on the patient's head, e.g. head bands
• CPC Class Codes: G02C 13/005 Measuring geometric parameters required to locate ophtalmic lenses in spectacles frames apparatus for testing or instruments for examining the eyes per se A61B3/00; machines or devices and accessories for grinding the edges of lenses using spectacles as a template B24B9/144

Abstract

The present invention measures the vertical and horizontal decentration of a pupil of a patient relative to a spectacle frame. The apparatus includes a housing having a distal end defining at least one target aperture. The housing has a proximal end opposite the distal end. An eye-piece is disposed at the proximal end and permits an operator to observe the pupil of the patient through the target aperture such that the eye-piece, the target aperture, the spectacle frame, and the pupil of the patient are in operative alignment. Also included is an adjustable left, right, and center vertical reference marker, each operatively coupled to the housing and horizontally displaceable relative thereto. The left and right vertical reference markers are configured to determine the position of a temporal edge and a nasal edge of the spectacle frame, respectively, while the center vertical reference marker is configured to be vertically aligned with the center of the pupil. The left, right, and center vertical reference markers are operatively coupled to a circuit which provides an electrical signal corresponding to a measurement of a horizontal distance between the center vertical reference marker and the left and right reference markers, respectively. This horizontal distance represents horizontal decentration.

Claims

1. An apparatus for measuring in combination, vertical and horizontal decentration of a pupil of a patient relative to a spectacle frame, the apparatus comprising:

a housing having a distal end defining at least one target aperture, said housing having a proximal end opposite the distal end;

an eye-piece disposed toward the proximal end, said eye-piece permitting an operator to observe the pupil of the patient through the target aperture such that the eye-piece, the target aperture, the spectacle frame, and the pupil of the patient are in operative alignment;

at least two adjustable horizontal reference markers, each operatively coupled to the housing and vertically displaceable relative thereto, one of the horizontal reference markers configured to be aligned with and intersect a center of the pupil, and the other horizontal reference marker configured to be aligned with at least one of an upper edge and a lower edge of the spectacle frame;

said at least two horizontal reference markers operatively coupled to a circuit which provides an electrical signal corresponding to a measurement of a vertical distance between the center of the pupil and at least one of the upper and lower edges of the spectacle frame, said vertical distance representing the vertical decentration;

at least two adjustable vertical reference markers, each operatively coupled to the housing and horizontally displaceable relative thereto, one of the vertical reference markers configured to be aligned with and intersect the center of the pupil, and the other vertical reference marker configured to be aligned with at least one of a temporal edge and a nasal edge of the spectacle frame; and

said at least two vertical reference markers operatively coupled to a circuit which provides an electrical signal corresponding to a measurement of a horizontal distance between the center of the pupil and at least one of the temporal and nasal edges of the spectacle frame, said horizontal distance representing the horizontal decentration.

2. An apparatus for measuring in combination, vertical and horizontal decentration of a pupil of a patient relative to a spectacle frame, the apparatus comprising:

a housing having a distal end defining at least one target aperture, said housing having a proximal end opposite the distal end;

an eye-piece disposed toward the proximal end, said eye-piece permitting an operator to observe the pupil of the patient through the target aperture such that the eye-piece, the target aperture, the spectacle frame, and the pupil of the patient are in operative alignment;

an adjustable upper, lower, and center horizontal reference marker, each operatively coupled to the housing and vertically displaceable relative thereto, said upper and lower horizontal reference markers configured to determine the position of an upper edge and lower edge of the spectacle frame, respectively, said center horizontal reference marker configured to be aligned with and intersect a center of the pupil;

said upper, lower, and center horizontal reference markers operatively coupled to a circuit which provides an electrical signal corresponding to a measurement of a vertical distance between the center horizontal reference marker and the upper and lower reference markers, respectively, said vertical distance representing the vertical decentration;

an adjustable left, right, and center vertical reference marker, each operatively coupled to the housing and horizontally displaceable relative thereto, said left and right vertical reference markers configured to determine the position of a temporal edge and a nasal edge of the spectacle frame, respectively, said center vertical reference marker configured to be aligned with and intersect the center of the pupil; and

said left, right, and center vertical reference markers operatively coupled to a circuit which provides an electrical signal corresponding to a measurement of a horizontal distance between the center vertical reference marker and the left and right reference markers, respectively, said horizontal distance representing the horizontal decentration.

3. An apparatus for measuring in combination, vertical and horizontal decentration of a pupil of a patient relative to a spectacle frame, the apparatus comprising:

a housing having a distal end defining at least one target aperture, said housing having a proximal end opposite the distal end;

an eye-piece disposed toward the proximal end, said eye-piece permitting an operator to observe the pupil of the patient through the target aperture such that the eye-piece, the target aperture, the spectacle frame, and the pupil of the patient are in operative alignment;

a horizontal reference marker configured to be aligned with and intersect a center of the pupil;

at least one horizontal platform configured to contact one of an upper and lower edge of the spectacle frame;

said horizontal reference marker and said at least one horizontal platform operatively coupled to the housing and vertically displaceable relative thereto;

said horizontal reference marker and said at least one horizontal platform operatively coupled to a circuit which provides an electrical signal corresponding to a measurement of a vertical distance between the horizontal reference marker and the at least one horizontal platform, said vertical distance representing the vertical decentration;

at least two adjustable vertical reference markers, each operatively coupled to the housing and horizontally displaceable relative thereto, one of the vertical reference markers configured to be aligned with and intersect the center of the pupil and the other configured to be aligned with at least one of a temporal edge and a nasal edge of the spectacle frame; and

said at least two vertical reference markers operatively coupled to a circuit which provides an electrical signal corresponding to a measurement of a horizontal distance between the center of the pupil and at least one of the temporal and nasal edges of the spectacle frame, said horizontal distance representing the horizontal decentration.

4. The apparatus according to claim 3 wherein the vertical reference markers are adjacent the target apertures and are displaceable in a direction relative to the target apertures so as to be maintained in a spaced-apart parallel orientation relative to the target apertures such that parallax measurement error is substantially eliminated.

5. The apparatus according to claim 3 further including an upper and a lower adjustable horizontal platform, said upper and lower platforms arranged to contact an upper and a lower edge of the spectacle frame, respectively, said horizontal reference marker configured to be aligned with and intersect the center of the pupil to provide an indication of a vertical distance between the horizontal reference marker and the upper and lower platforms, respectively.

6. The apparatus according to claim 3 wherein the vertical reference markers include a left, right, and center vertical reference markers, said left and right vertical reference markers arranged to be aligned with the left and the right edges of the spectacle frame, respectively, the center vertical reference marker configured to be aligned with and intersect the center of the pupil while disposed vertically between the left and right vertical reference markers.

7. The apparatus according to claim 3 further including means for establishing and maintaining the housing at a fixed position relative to the spectacle frame, said means for establishing and maintaining being oriented relative to a longitudinal axis of the housing, the longitudinal axis passing between the target apertures.

8. The apparatus according to claim 7 further including a chin rest and a forehead rest disposed along the longitudinal axis and external to the housing, the chin rest vertically displaceable relative the housing, and the forehead rest forwardly and backwardly displaceable along the longitudinal axis.

9. The apparatus according to claim 3 wherein the circuits which provide electrical signals corresponding to the measurement of a horizontal distance and a vertical distance include electronic means configured to receive the electronic signals and visually indicate numerical values corresponding to the electronic signals.

10. An apparatus for measuring in combination, vertical and horizontal decentration of a pupil of a patient relative to a spectacle frame, the apparatus comprising:

a housing having a distal end defining at least one target aperture, said housing having a proximal end opposite the distal end;

an eye-piece disposed toward the proximal end, said eye-piece permitting an operator to observe the pupil of the patient through the target aperture such that the eye-piece, the target aperture, the spectacle frame, and the pupil of the patient are in operative alignment;

a horizontal reference marker configured to be aligned with and intersect a center of the pupil;

an upper and a lower horizontal platform configured to contact an upper and lower edge of the spectacle frame, respectively;

said horizontal reference marker and the horizontal platforms operatively coupled to the housing and vertically displaceable relative thereto;

said horizontal reference marker and said horizontal platforms operatively coupled to a circuit which provides an electrical signal corresponding to a measurement of a vertical distance between the horizontal reference marker and the upper and lower platforms, respectively, said vertical distance representing the vertical decentration;

at least two adjustable vertical reference markers, each operatively coupled to the housing and horizontally displaceable relative thereto, one of the vertical reference markers configured to be aligned with and intersect the center of the pupil, and the other vertical reference marker configured to be aligned with at least one of a temporal edge and a nasal edge of the spectacle frame; and

said at least two vertical reference markers operatively coupled to a circuit which provides an electrical signal corresponding to a measurement of a horizontal distance between the center of the pupil and at least one of the temporal and nasal edges of the spectacle frame, said horizontal distance representing the horizontal decentration.

11. An apparatus for measuring in combination, vertical and horizontal decentration of a pupil of a patient relative to a spectacle frame, the apparatus comprising:

a housing having a distal end defining at least one target aperture, said housing having a proximal end opposite the distal end;

an eye-piece disposed toward the proximal end, said eye-piece permitting an operator to observe the pupil of the patient through the target aperture such that the eye-piece, the target aperture, the spectacle frame, and the pupil of the patient are in operative alignment;

a horizontal reference marker configured to be aligned with and intersect a center of the pupil;

at least one horizontal platform configured to contact one of an upper and lower edge of the spectacle frame;

said horizontal reference marker and said at least one horizontal platform operatively coupled to the housing and vertically displaceable relative thereto;

said horizontal reference marker and said at least one horizontal platform operatively coupled to a circuit which provides an electrical signal corresponding to a measurement of a vertical distance between the horizontal reference marker and the at least one horizontal platform, said vertical distance representing the vertical decentration;

an adjustable left, right, and center vertical reference marker, each operatively coupled to the housing and horizontally displaceable relative thereto, said left and right vertical reference markers configured to determine the position of a temporal edge and a nasal edge of the spectacle frame, respectively, said center vertical reference marker configured to be aligned with and intersect the center of the pupil; and

said left, right, and center vertical reference markers operatively coupled to a circuit which provides an electrical signal corresponding to a measurement of a horizontal distance between the center vertical reference marker and the left and right reference markers, respectively, said horizontal distance representing the horizontal decentration.

12. An apparatus for measuring horizontal decentration of a pupil of a patient relative to a spectacle frame, the apparatus comprising:

a housing having a distal end defining at least one target aperture, said housing having a proximal end opposite the distal end;

an eye-piece disposed toward the proximal end, said eye-piece permitting an operator to observe the pupil of the patient through the target aperture such that the eye-piece, the target aperture, the spectacle frame, and the pupil of the patient are in operative alignment;

at least two adjustable vertical reference markers, each operatively coupled to the housing and horizontally displaceable relative thereto, one of the vertical reference markers configured to be aligned with and intersect the center of the pupil, and the other vertical reference marker configured to be aligned with at least one of a temporal edge and a nasal edge of the spectacle frame; and

said at least two vertical reference markers operatively coupled to a circuit which provides an electrical signal corresponding to a measurement of a horizontal distance between the center of the pupil and at least one of the temporal and nasal edges of the spectacle frame, said horizontal distance representing the horizontal decentration.

13. A method for measuring in combination, vertical and horizontal decentration of a pupil of a patient relative to a spectacle frame, the method comprising the steps of:

a) operatively fixing a position of a housing relative to a head of a patient, said housing having a proximal and a distal end, said distal end defining at least one target aperture so that a line of sight of the patient is directed into the at least one target aperture;

b) observing the pupil of the patient by viewing the pupil through an eye-piece disposed toward the proximal end of the housing such that the eye-piece, the target aperture, the spectacle frame, and said pupil of the patient are in operative alignment;

c) aligning a lower horizontal platform and an upper horizontal platform with lower and upper edges of the spectacle frame, respectively;

d) aligning a horizontal reference marker with a center of the pupil so that the horizontal reference marker intersects said center of the pupil;

e) determining a measurement of the vertical decentration represented by a position of the horizontal reference marker relative to the position of the upper and lower horizontal platforms, respectively;

f) aligning a left and a right vertical reference marker with a left and a right edge of a single lens portion of the spectacle frame, respectively;

g) aligning a center vertical reference marker with the center of the pupil so that the vertical reference marker intersects said center of the pupil;

h) determining a measurement of the horizontal decentration represented by a position of the center vertical reference marker relative to the position of the left and right vertical reference markers, respectively;

i) repeating steps b) through h) for the other pupil of the patient; and

j) displaying the values of the measured vertical and horizontal decentration.

14. A method for measuring in combination vertical and horizontal decentration with respect to pupil of a patient and a spectacle frame, the method comprising the steps of:

a) operatively fixing a position of a measuring device relative to a head of a patient, said measuring device having a proximal and a distal end, said distal end defining at least one target aperture so that a line of sight of the patient is directed into the at least one target aperture;

b) determining a vertical height of the spectacle frame measured between an upper and lower edge of the spectacle frame;

c) determining a vertical center of the pupil of the patent relative to the vertical height of the spectacle frame;

d) dividing the vertical height of the spectacle frame by two and subtracting the value of the vertical center of the pupil to obtain a value representing the vertical decentration;

e) determining a horizontal width of a single lens portion of the spectacle frame measured between a left and a right edge of the single lens portion of the frame spectacle;

f) determining a horizontal center of the pupil of the patient relative to the horizontal width;

g) dividing the horizontal width by two and subtracting the value of the horizontal center of the pupil to obtain a value representing horizontal decentration;

h) repeating steps b) through f) for the other pupil of the patient; and

j) displaying the values of the measured vertical and horizontal decentration.