OPHTHALMIC PHOTOGRAPHING APPARATUS

• US 20150055089A1
• Filed: 07/01/2014
• Published: 02/26/2015
• Est. Priority Date: 07/02/2013
• Status: Abandoned Application

• Current Assignee: Nidek Company Limited
• Original Assignee: Nidek Company Limited
• Inventors: HIGUCHI, Yukihiro, AONO, Hideki
• Application Number:
  US14/321,049
• Publication Number:
  US 20150055089A1
• Time in Patent Office: Days
• US Class Current: 351/206
• CPC Class Codes: A61B 3/0025 characterised by electronic signal processing, e.g. eye models
• CPC Class Codes: A61B 3/102 for optical coherence tomography [OCT]

Abstract

An ophthalmic photographing apparatus including an OCT optical system for acquiring an OCT signal of a subject eye; an optical scanner for scanning the subject eye by the measurement light applied to the subject eye; a scan controller for controlling driving of the optical scanner and operate first scan control of respectively performing one scan by measurement light with respect to each of plural scan lines and second scan control of performing plural scans by measurement light with respect to each of the plural scan lines; and an image processor for acquiring the OCT signal in each scan line based on an output signal from the OCT optical system and perform composite processing on a plurality of the OCT signals of each scan line acquired by the second scan control using the OCT signal of each scan line acquired by the first scan control as a template.

Claims

1. An ophthalmic photographing apparatus comprising:

an OCT optical system configured to acquire an OCT signal of a subject eye using interference between reference light and measurement light applied to the subject eye;

an optical scanner configured to scan the subject eye by the measurement light applied to the subject eye;

a scan controller configured to control driving of the optical scanner and operate first scan control of respectively performing one scan by measurement light with respect to each of plural scan lines and second scan control of performing plural scans by measurement light with respect to each of the plural scan lines; and

an image processor configured to acquire the OCT signal in each scan line by the scan controller based on an output signal from the OCT optical system and perform composite processing on a plurality of the OCT signals of each scan line acquired by the second scan control using the OCT signal of each scan line acquired by the first scan control as a template.

2. The ophthalmic photographing apparatus as claimed in claim 1, wherein, as the composite processing, the image processor adds and averages the plurality of tomographic images acquired by the second scan control using the OCT signal acquired by the first scan control as a template.

3. The ophthalmic photographing apparatus as claimed in claim 1, wherein in a case of setting a scan pattern in which plural scan lines having relations equal in a first scanning direction and different in a second scanning direction are arranged adjacently, the image processor forms three-dimensional OCT data based on the tomographic image of each scan line in which composite processing is performed.

4. The ophthalmic photographing apparatus as claimed in claim 1, wherein the scan controller is configured to operate first scan control of sequentially performing one scan by measurement light in each scan line and second scan control of sequentially performing plural scans in each scan line in the case of performing plural scans by measurement light with respect to each of the plural scan lines.

5. The ophthalmic photographing apparatus as claimed in claim 1, wherein the scan controller continuously performs the first scan control and the second scan control.

6. The ophthalmic photographing apparatus as claimed in claim 1, wherein the image processor further determines whether or not an OCT signal acquired by the second scan control is proper as an object signal with respect to the OCT signal acquired by the first scan control as a template, and makes a choice based on the determination result.

7. The ophthalmic photographing apparatus as claimed in claim 1, wherein, as the composite processing, the image processor measures a change between signals in the plurality of OCT signals acquired by the second scan control with respect to the OCT signal acquired by the first scan control as a template.

8. The ophthalmic photographing apparatus as claimed in claim 1, wherein the image processor performs Fourier transformation of an output signal from the OCT optical system and acquires a signal after performing the Fourier transformation as the OCT signal.

9. The ophthalmic photographing apparatus as claimed in claim 1, wherein the scan controller performs first scan control and second scan control by a raster scan.

10. The ophthalmic photographing apparatus as claimed in claim 1, wherein the image processor acquires first OCT three-dimensional data based on an OCT signal of each scan line acquired by the first scan control, and acquires second OCT three-dimensional data based on an OCT signal of each scan line acquired by the second scan control.

11. The ophthalmic photographing apparatus as claimed in claim 1, wherein the scan controller changes a scan condition between first scan control and second scan control.

12. The ophthalmic photographing apparatus as claimed in claim 1, wherein the scan controller changes at least any of a scan speed, a scan width, a scan line spacing, and exposure time of a light receiving element formed in the OCT optical system between the first scan control and the second scan control.

13. The ophthalmic photographing apparatus as claimed in claim 1, wherein the scan controller performs the first scan control and then performs the second scan control later.

14. The ophthalmic photographing apparatus as claimed in claim 1, wherein

the image processor:

generates first OCT three-dimensional data based on the OCT signal of each scan line acquired by the first scan control;

acquires a first OCT front image based on the generated first OCT three-dimensional data;

generates a plurality of second OCT three-dimensional data based on the OCT signals of each scan line acquired by the second scan control; and

acquires a plurality of second OCT front images based on the generated second OCT three-dimensional data.

15. The ophthalmic photographing apparatus as claimed in claim 14, wherein the image processor corrects a misalignment of the plurality of second OCT front images using the first OCT front image.

16. A computer-readable storage medium for storing an ophthalmic image processing program executed in an ophthalmic image processing apparatus for processing a tomographic image of a subject eye acquired by ophthalmic optical coherence tomography,

the ophthalmic optical coherence tomography comprising:

an OCT optical system configured to acquire a tomographic image of the subject eye using interference between reference light and measurement light applied to the subject eye,

an optical scanner configured to scan the subject eye by the measurement light applied to the subject eye, and

a scan controller configured to control driving of the optical scanner, the scan controller capable of operating first scan control of respectively performing one scan by measurement light with respect to each of plural scan lines and second scan control of performing plural scans by measurement light with respect to each of the plural scan lines,

the ophthalmic image processing program executed by a processor of the ophthalmic image processing apparatus causing the ophthalmic image processing apparatus to execute performing composite processing of plural OCT signals of each scan line acquired by the second scan control using an OCT signal of each scan line acquired by the first scan control as a template image by being executed by a processor of the ophthalmic image processing apparatus.