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EP-4740834-A1 - OPHTHALMOLOGIC APPARATUS AND METHOD FOR CONTROLLING THE SAME

EP4740834A1EP 4740834 A1EP4740834 A1EP 4740834A1EP-4740834-A1

Abstract

An ophthalmologic apparatus (1, 1A) includes a display portion (22) that is configured to display an astigmatism test chart (45, 45A) for obtaining an astigmatism axis angle of an examinee (S); and a control portion (34, 80) that is configured to control the display portion (22) to display and rotate the astigmatism test chart (45, 45A) on the display portion (22). The astigmatism test chart (45, 45A) includes a first visual target (46) including a plurality of first straight lines (46a) that are arranged in parallel with each other at a predetermined interval, and a second visual target (47) including a plurality of second straight lines (47a) that are arranged in parallel with each other at a predetermined interval and extend in a direction orthogonal to a direction of the first straight lines (46a). The first visual target (46) is displayed in a circular first area (48), and the second visual target (47) is displayed in an annular second area (49) surrounding the first area (48).

Inventors

  • SAKURADA, TOMOHIRO

Assignees

  • Topcon Corporation

Dates

Publication Date
20260513
Application Date
20251107

Claims (12)

  1. An ophthalmologic apparatus (1, 1A) comprising: a display portion (22) that is configured to display an astigmatism test chart (45, 45A) for obtaining an astigmatism axis angle of an examinee (S); and a control portion (34, 80) that is configured to control the display portion (22) to display and rotate the astigmatism test chart (45, 45A) on the display portion (22), wherein the astigmatism test chart (45, 45A) comprises: a first visual target (46) comprising a plurality of first straight lines (46a) that are arranged in parallel with each other at a predetermined interval, and a second visual target (47) comprising a plurality of second straight lines (47a) that are arranged in parallel with each other at a predetermined interval and extend in a direction orthogonal to a direction of the first straight lines (46a), wherein the first visual target (46) is displayed in a circular first area (48), and the second visual target (47) is displayed in an annular second area (49) surrounding the first area (48).
  2. The ophthalmologic apparatus (1, 1A) according to claim 1, further comprising an examinee's controller (35) that is configured to receive an operation of the examinee (S), wherein the control portion (34, 80) is configured to change at least one of a width of the first straight lines (46a), an interval between the first straight lines (46a), a width of the second straight lines (47a), and an interval between the second straight lines (47a) based on the operation of the examinee (S) on the examinee's controller (35).
  3. The ophthalmologic apparatus (1, 1A) according to claim 1 or 2, wherein at least a part of an outline of the first and second straight lines (46a, 47a) of the astigmatism test chart (45, 45A) is blurred.
  4. The ophthalmologic apparatus (1, 1A) according to claim 3, wherein brightness in a width direction of at least a part of the first and second straight lines (46a, 47a) in the astigmatism test chart (45, 45A) changes according to a sinusoidal function.
  5. The ophthalmologic apparatus (1, 1A) according to any one of claims 1 to 4, further comprising a measurement optical system (10) arranged between a subject eye of the examinee (S) and the astigmatism test chart (45, 45A), the measurement optical system (10) comprising an optical element whose power and axial direction are changeable, wherein the control portion (34, 80) is configured to control the display portion (22) to display and rotate the astigmatism test chart (45, 45A) on the display portion (22) and to stop rotation of the astigmatism test chart (45, 45A) when the examinee (S) clearly sees the first visual target (46), and wherein the control portion (34, 80) is configured to control the measurement optical system (10) to set the axial direction of the optical element at a predetermined angle set based on an inclination direction of the first visual target (46) in a state where the rotation of the astigmatism test chart (45, 45A) is stopped, and to change the power of the optical element so that the examinee (S) clearly sees the second visual target (47).
  6. The ophthalmologic apparatus (1, 1A) according to any one of claims 1 to 5, wherein the control portion (34, 80) is configured to control the display portion (22) to display a radial chart (41) comprising a plurality of radial lines (42) extending in a radial direction, and wherein the control portion (34, 80) is configured to start rotation of the astigmatism test chart (45, 45A) from a position where the first straight lines (46a) are along the radial line (42) clearly seen by the examinee (S).
  7. The ophthalmologic apparatus (1, 1A) according to claim 6, wherein the control portion (34, 80) is configured to control the display portion (22) to simultaneously display the radial chart (41) and a marker (43) in vicinity of a distal end of one of the radial lines (42) of the radial chart (41), and wherein the control portion (34, 80) is configured to control the display portion (22) to sequentially move the marker (43) and then fix the marker (43) in vicinity of a distal end of the radial line (42) that is clearly seen by the examinee (S).
  8. The ophthalmologic apparatus (1, 1A) according to any one of claims 1 to 7, wherein when the display portion (22) displays and rotates the astigmatism test chart (45, 45A), the control portion (34, 80) is configured to perform a first phase in which the astigmatism test chart (45, 45A) is rotated by 360 degrees, prior to a second phase in which a rotation angle of the astigmatism test chart (45, 45A) is adjusted according to visual perception of the examinee (S) of the astigmatism test chart (45, 45A).
  9. The ophthalmologic apparatus (1, 1A) according to any one of claims 1 to 8, further comprising an examinee's controller (35) comprising a dial member (36a) that is rotated by the examinee (S), and wherein the control portion (34, 80) is configured to control the display portion (22) according to a rotation angle of the dial member (36a).
  10. A method for controlling an ophthalmologic apparatus (1, 1A), wherein the ophthalmologic apparatus (1, 1A) comprises: a display portion (22) that is configured to display an astigmatism test chart (45, 45A) for obtaining an astigmatism axis angle of an examinee (S); and a control portion (34, 80) that is configured to control the display portion (22) to display and rotate the astigmatism test chart (45, 45A) on the display portion (22), wherein the method comprises displaying the astigmatism test chart (45, 45A) on the display portion (22), the astigmatism test chart (45, 45A) comprising a first visual target (46) comprising a plurality of first straight lines (46a) that are arranged in parallel with each other at a predetermined interval, and a second visual target (47) comprising a plurality of second straight lines (47a) that are arranged in parallel with each other at a predetermined interval and extend in a direction orthogonal to a direction of the first straight lines (46a), and wherein the displaying the astigmatism test chart (45, 45A) comprises: displaying the first visual target (46) in a circular first area (48), and displaying the second visual target (47) in an annular second area (49) surrounding the first area (48).
  11. The method according to claim 10, wherein the ophthalmologic apparatus (1, 1A) further comprises an examinee's controller (35) that is configured to receive an operation of the examinee (S), wherein the method further comprises changing at least one of a width of the first straight lines (46a), an interval between the first straight lines (46a), a width of the second straight lines (47a), and an interval between the second straight lines (47a) based on the operation of the examinee (S) on the examinee's controller (35).
  12. The method according to claim 10 or 11, wherein the ophthalmologic apparatus (1, 1A) further comprises a measurement optical system (10) that is arranged between a subject eye of the examinee (S) and the astigmatism test chart (45, 45A), the measurement optical system (10) comprising an optical element whose power and axial direction are changeable, wherein the method further comprises: displaying the astigmatism test chart (45, 45A) on the display portion (22); rotating the astigmatism test chart (45, 45A) displayed on the display portion (22); stopping rotation of the astigmatism test chart (45, 45A) when the examinee (S) clearly sees the first visual target (46); setting the axial direction of the optical element at a predetermined angle set based on an inclination direction of the first visual target (46) when the rotation of the astigmatism test chart (45, 45A) is stopped; and changing the power of the optical element so that the examinee (S) clearly sees the second visual target (47) when the axial direction of the optical element is set at the predetermined angle.

Description

FIELD OF THE INVENTION The present invention relates to an ophthalmologic apparatus and a method for controlling the same. BACKGROUND Prior art such as Japanese Utility Model Application Publications S52-042595 and S59-071601 discloses an ophthalmologic apparatus configured to display and rotate an astigmatism test chart including two groups of straight lines oriented at 90° to each other, enabling subjective determination of the astigmatic axis angle of an examinee. The astigmatic axis angle is determined from the examinee's simultaneous visual comparison of the two groups. SUMMARY The ophthalmologic apparatus disclosed in Japanese Utility Model Application Publication S52-042595 displays an astigmatism chart in which two groups of straight lines are displayed apart from one another, and each group is enclosed by an outline that terminates the line ends at the boundary. This configuration makes simultaneous visual comparison difficult because the examinee must shift the line of sight to observe the two groups of lines. The ophthalmologic apparatus disclosed in Japanese Utility Model Application Publication S59-071601 displays an astigmatism chart in which the opposing ends of two groups of straight lines are aligned on a common virtual straight line, either placed adjacent along the line or overlapping one another on the line. This arrangement reduces the need for the examinee to shift the line of sight during simultaneous comparison of the two groups. However, since the two groups face each other across the virtual line, further improvement in facilitating simultaneous comparison remains desirable. The present invention has been made in view of the foregoing problem. An object of the present invention is to provide an ophthalmologic apparatus and a method for controlling the ophthalmologic apparatus that facilitate simultaneous visual comparison of two groups of straight lines extending in mutually perpendicular directions. The present invention provides an ophthalmologic apparatus including a display portion that is configured to display an astigmatism test chart for obtaining an astigmatism axis angle of an examinee; and a control portion that is configured to control the display portion to display and rotate the astigmatism test chart on the display portion. The astigmatism test chart includes a first visual target including a plurality of first straight lines that are arranged in parallel with each other at a predetermined interval, and a second visual target including a plurality of second straight lines that are arranged in parallel with each other at a predetermined interval and extend in a direction orthogonal to a direction of the first straight lines. The first visual target is displayed in a circular first area, and the second visual target is displayed in an annular second area surrounding the first area. The present invention also provides a method for controlling an ophthalmologic apparatus. The ophthalmologic apparatus includes a display portion that is configured to display an astigmatism test chart for obtaining an astigmatism axis angle of an examinee; and a control portion that is configured to control the display portion to display and rotate the astigmatism test chart on the display portion. The method includes displaying the astigmatism test chart on the display portion. The astigmatism test chart includes a first visual target including a plurality of first straight lines that are arranged in parallel with each other at a predetermined interval, and a second visual target including a plurality of second straight lines that are arranged in parallel with each other at a predetermined interval and extend in a direction orthogonal to a direction of the first straight lines. The displaying the astigmatism test chart includes displaying the first visual target in a circular first area and displaying the second visual target in an annular second area surrounding the first area. According to the ophthalmologic apparatus and the method for controlling the ophthalmologic apparatus of the present invention with the above configuration, the simultaneous visual comparison of two groups of straight lines extending in mutually perpendicular directions is facilitated. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a schematic view of an ophthalmologic apparatus according to a first embodiment. FIG. 2 is a schematic view of a control system in the ophthalmologic apparatus of the first embodiment. FIG. 3 is a schematic perspective view of a second controller. FIG. 4 is a schematic view of a radial chart. FIG. 5 is a schematic view of an astigmatism test chart.FIG. 6A is a schematic view showing brightness of a first visual target. FIG. 6B is an enlarged view of a portion of a first straight line. FIG. 7 is a schematic view showing brightness of a second visual target. FIG. 8 is a flowchart of an astigmatism test procedure using the ophthalmologic apparatus of the first embodiment. FIG. 9 is a perspective vi