Adaptor and method for capturing images of a retina of an eye

An adaptor for attachment to a portable image capturing device including a camera for capturing images of a retina of an eye, the adaptor comprising:

• an illumination unit;
• a beam splitter;
• an objective lens system;
• a secondary lens system;
• the illumination unit comprising an optical radiation source, the illumination unit being configured to direct optical radiation from the optical radiation source to the beam splitter;
• the beam splitter being positioned between the objective lens system and the secondary lens system and being configured to direct the optical radiation to the objective lens system for illuminating the retina;
• the objective lens system being configured to focus the optical radiation on a focal plane positioned between a cornea and a backside of a crystalline lens of the eye and direct optical radiation reflected from the retina towards the secondary lens system;
• the secondary lens system being configured to direct the reflected optical radiation to an exterior of the adaptor for reception by a camera of a portable image capturing device which is to be attached to the adaptor;
• wherein the objective lens system and the secondary lens system share a first optical axis;
• and wherein the adaptor is configured to attach to the portable image capturing device in a position in which the camera of the portable image capturing device is offset from the first optical axis.

A method of capturing an image of a retina of an eye comprising:

• attaching an adaptor to a portable image capturing device including a camera;
• generating optical radiation by an optical radiation source of an illumination unit of the adaptor;
• directing the optical radiation from the illumination unit through a condensing lens system on an illumination path to a beam splitter and from the beam splitter to an objective lens system;
• focusing the illumination path optical radiation by the objective lens system onto a focal plane positioned between a cornea and a backside of a crystalline lens of the eye, wherein the eye is not in contact with the adaptor;
• receiving, by the objective lens system, optical radiation reflected by the retina of the eye and directing the reflected optical radiation on an imaging path through the beam splitter to a secondary lens system;
• directing optical radiation on the imaging path, by the secondary lens system, onto a camera of portable image capturing device;
• wherein the objective lens system and the secondary lens system share a first optical axis and the condensing lens system has a second optical axis which is at an angle to the first optical axis;
• and
• wherein the camera of the portable image capturing device is offset from the first optical axis and/or an illumination aperture associated with the illumination unit is offset from the second optical axis.