FUNDUS PHOTOGRAPHING APPARATUS

• US 20120113389A1
• Filed: 11/01/2011
• Published: 05/10/2012
• Est. Priority Date: 11/04/2010
• Status: Active Grant

• Current Assignee: Nidek Company Limited
• Original Assignee: Nidek Company Limited
• Inventors: HANEBUCHI, Masaaki, MUKAI, Hideo, YAMADA, Yoshihiko
• Granted Patent: US 8,801,178 B2
• Time in Patent Office: Days
• US Class Current: 351/208
• CPC Class Codes: A61B 3/1015 for wavefront analysis
• CPC Class Codes: A61B 3/113 for determining or recording eye movement
• CPC Class Codes: A61B 3/14 Arrangements specially adapted for eye photography apparatus or arrangements for taking photographs per se G03B
• CPC Class Codes: A61B 3/156 for blocking

Abstract

A fundus photographing apparatus includes a wavefront detecting optical system having a wavefront sensor for receiving reflection light from a fundus and measuring wavefront aberration of an eye, a wavefront compensating device for compensating the wavefront aberration, and a deviation detecting part for detecting deviation information corresponding to deviation between an effective region in which aberration compensation by the wavefront compensating device is effective, and a wavefront measuring region in which the wavefront aberration is measured by the wavefront detecting optical system, with respect to a direction perpendicular to an optical axial direction.

Claims

1. A fundus photographing apparatus, comprising:

a photographing optical system including

a light source,

an optical system for irradiating a fundus with light from the light source, and

an optical system for receiving first reflection light from the fundus and photographing a fundus image;

a wavefront detecting optical system having a wavefront sensor for receiving second reflection light from the fundus and measuring wavefront aberration of an eye;

a wavefront compensating device disposed on an optical path of the photographing optical system for compensating the wavefront aberration by controlling a wavefront of incident light; and

a deviation detecting part for detecting deviation information corresponding to deviation between an effective region and a wavefront measuring region with respect to a direction perpendicular to an optical axial direction, wherein aberration compensation by the wavefront compensating device is effective in the effective region and the wavefront aberration is measurable by the wavefront detecting optical system in the wavefront measuring region.

2. The fundus photographing apparatus according to claim 1, further comprising:

a control unit for performing feedback control of the wavefront compensating device based on a detection signal from the wavefront sensor to compensate the wavefront aberration and temporarily stopping the feedback in a case where the deviation information detected at the deviation detecting part is out of an allowable range while resuming the feedback in a case where the deviation information is returned in the allowable range.

3. The fundus photographing apparatus according to claim 2, wherein the control unit is adapted to maintain an aberration-compensating amount of the wavefront compensating device to an aberration-compensating amount before the deviation information is out of the allowable range when the control unit stops the feedback.

4. The fundus photographing apparatus according to claim 2, further comprising:

a memory for storing wavefront control information of the wavefront compensating device, wherein

the control unit is adapted to store on the memory the wavefront control information for a case where the deviation information falls within the allowable range and to control the wavefront compensating device by using the wavefront control information to be stored on the memory in a case where the deviation information is returned in the allowable range.

5. The fundus photographing apparatus according to claim 1, further comprising:

a tracking system for relatively adjusting a positional relation between the wavefront detecting optical system and an examinee'"'"'s eye in such a manner that the deviation information falls within the allowable range.

6. The fundus photographing apparatus according to claim 5, wherein the tracking system includes an optical deflecting part disposed on an optical path of the wavefront detecting optical system for changing a traveling direction of light and is adapted to drive the optical deflecting part to adjust the positional relation.

7. The fundus photographing apparatus according to claim 1, further comprising:

a control unit for performing feedback control of the wavefront compensating device based on a detection signal from the wavefront sensor to compensate the wavefront aberration and adjusting a position of the effective region in such a manner that the deviation information falls within an allowable range in a case where the deviation information detected at the deviation detecting part is out of the allowable range.

8. The fundus photographing apparatus according to claim 7, wherein, for adjusting the position of the effective region, the control unit is adapted to control the wavefront compensating device for a case where the effective region is a second effective region after positional adjustment by using wavefront control information for a case where the effective region is a first effective region before positional adjustment.

9. The fundus photographing apparatus according to claim 8, wherein the control unit is adapted to temporarily stop the feedback in a case where the deviation information detected at the deviation detecting part is out of the allowable range and to resume the feedback after performing adjustment such that the effective region is to be the second effective region.

10. The fundus photographing apparatus according to claim 1, wherein the deviation detecting part is adapted to detect, as the deviation information, information corresponding to deviation between a region of the wavefront sensor corresponding to the effective region of the wavefront compensating device and a light-receiving region of the wavefront sensor.

11. The fundus photographing apparatus according to claim 1, further comprising:

an observing optical system for observing an anterior segment front image of the examinee'"'"'s eye; and

a pupil position detecting part for detecting a pupil position from the anterior segment front image to be photographed by the observing optical system, wherein

the deviation detecting part is adapted to detect, as the deviation information, deviation information corresponding to deviation between the pupil position to be detected by the pupil position detecting part and an optical axis of the wavefront detecting optical system.

12. The fundus photographing apparatus according to claim 11, wherein the pupil position detecting part is adapted to extract a pupil outer edge part by processing the anterior segment front image to be photographed by the observing optical system and to detect the pupil position based on the outer edge part to be extracted.

13. The fundus photographing apparatus according to claim 11, further comprising:

a target light projecting optical system for forming an alignment target at a cornea by projecting alignment light to the examinee'"'"'s eye; and

a target detecting optical system for detecting the alignment target to be formed at the cornea, wherein

the pupil position detecting part is adapted to detect the pupil position based on a detection result from the target detecting optical system.