Ophthalmologic apparatus

Patent metadata

Field	Value
Publication number	US-9456742-B2
Application number	US-201213651632-A
Country	US
Kind code	B2
Filing date	Oct 15, 2012
Priority date	Oct 27, 2011
Publication date	Oct 4, 2016
Grant date	Oct 4, 2016

Abstract

In order to take a good tomographic image without a complicated position adjustment operation by an inspector, an ophthalmologic apparatus is provided which acquires a fundus tomographic image by optical coherence tomography utilizing interference by low coherence light. The ophthalmologic apparatus includes a tomographic image acquiring unit for acquiring a tomographic image of an eye to be inspected, a tilt calculation unit for calculating a tilt of the tomographic image, and a relative position changing unit for changing a relative position between the tomographic image acquiring unit and the eye to be inspected based on the tilt of the tomographic image. An evaluation index may be devised that indicates a problem with the tomographic image or an anterior ocular image and the relative position changing means may change the relative position according to this evaluation index. The evaluation index is linked to the tilt of the tomographic image.

First claim

What is claimed is:

1. An ophthalmologic apparatus, comprising:
a tomographic image acquiring unit configured to acquire a tomographic image of a fundus of an eye to be inspected, the tomographic image being a two-dimensional image including a depth direction of the fundus of the eye to be inspected;
an evaluation index calculation unit configured to calculate an image evaluation index of the tomographic image;
a tilt calculation unit configured to calculate a tilt of a first tomographic image acquired by the tomographic image acquiring unit;
a relative position changing unit configured to change a relative position between the tomographic image acquiring unit and the eye, by relatively moving the tomographic image acquiring unit in a plane perpendicular to an optical axis of the tomographic image acquiring unit, based on the tilt of the first tomographic image, so as to reduce the tilt of a second tomographic image acquired by the tomographic image acquiring unit, wherein the second tomographic image is acquired after the first tomographic image is acquired; and
a display control unit configured to cause a display unit to display information that the relative position is changed by the relative position changing unit,
wherein the tilt of the second tomographic image is reduced such that the image evaluation index of the second tomographic image is greater than the image evaluation index of the first tomographic image.

2. An ophthalmologic apparatus according to claim 1 , wherein the tilt calculation unit is configured to calculate the tilt based on a position of a predetermined layer in the tomographic image.

3. An ophthalmologic apparatus according to claim 1 , wherein the tilt calculation unit is configured to calculate the tilt based on distances between each of two points on a predetermined layer and a predetermined position in the tomographic image.

4. An ophthalmologic apparatus according to claim 3 , wherein the relative position changing unit is configured to change the relative position between the tomographic image acquiring unit and the eye so that the distances between the each of the two points on the predetermined layer and the predetermined position in the tomographic image are equal to each other.

5. An ophthalmologic method comprising:
acquiring a tomographic image of a fundus of an eye to be inspected using a tomographic image acquiring means, the tomographic image being a two-dimensional image including a depth direction of the fundus of the eye to be inspected;
calculating an image evaluation index of the tomographic image;
calculating a tilt of a first tomographic image acquired using the tomographic image acquiring means;
changing a relative position between the tomographic image acquiring means and the eye to be inspected, by relatively moving the tomographic image acquiring means in a plane perpendicular to an optical axis of the tomographic image acquiring means, based on the tilt of the first tomographic image, so as to reduce the tilt of a second tomographic image acquired by the tomographic image acquiring means,
wherein the second tomographic image is acquired after the first tomographic image is acquired; and
causing a display unit to display information of the changed relative position,
wherein the tilt of the second tomographic image is reduced such that the image evaluation index of the second tomographic image is greater than the image evaluation index of the first tomographic image.

6. An ophthalmologic apparatus according to claim 1 , further comprising a table in which the tilt of the tomographic image is associated with a moving amount of the tomographic image acquiring unit, wherein the relative position changing unit determines the moving amount of the tomographic image acquiring unit based on the table.

7. An ophthalmologic method according to claim 5 , wherein in the step of calculating the tilt, the tilt is calculated based on a position of a predetermined layer in the tomographic image.

8. An ophthalmologic method according to claim 5 , wherein in the step of calculating the tilt, the tilt is calculated based on distances between each of two points on a predetermined layer and a predetermined position in the tomographic image.

9. An ophthalmologic method according to claim 8 , wherein in the step of changing the relative position, the relative position between the tomographic image acquiring means and the eye is changed so that the distances between the each of the two points on the predetermined layer and the predetermined position in the tomographic image are equal to each other.

10. An ophthalmologic method according to claim 5 , wherein in the step of changing the relative position, a moving amount of the tomographic image acquiring means is determined based on a table in which the tilt of the tomographic image is associated with a moving amount of the tomographic image acquiring means.

11. A non-transitory tangible medium having recorded thereon a program for causing a computer to perform steps of the ophthalmologic method according to claim 5 .

12. An ophthalmologic apparatus according to claim 3 , wherein the predetermined layer is a retinal pigment epithelium layer.

13. An ophthalmologic apparatus according to claim 3 , wherein the predetermined layer is a nerve fiber layer.

14. An ophthalmologic apparatus according to claim 1 , wherein the image evaluation index is a Q index.

15. An ophthalmologic method according to claim 5 , wherein the image evaluation index is a Q index.

Assignees

• Canon Kk

Inventors

• Muto Kenji

Classifications

• A61B3/102 Primary

  for optical coherence tomography [OCT] · CPC title

• G01B9/02068

  Auto-alignment of optical elements · CPC title

• A61B5/0066

  Optical coherence imaging · CPC title

• A61B3/0075

  provided with adjusting devices, e.g. operated by control lever · CPC title

• G01B9/02044

  Imaging in the frequency domain, e.g. by using a spectrometer · CPC title