Ophthalmic apparatus and alignment method

An ophthalmic apparatus, comprising:

• an alignment arrangement for imaging of fundus of an eye with:
• an illumination arrangement configured to direct illumination light through an illumination path toward a second target plane where the illumination light has an illumination waist, and
• means for:
• outputting rays of alignment light of a first alignment pattern in a converging manner toward a first target plane, forming a predetermined reflection pattern of the first alignment pattern on said first target plane based on the convergence, causing the rays of the alignment light to have an alignment light waist zone that includes the first target plane based on the convergence, and causing a reflection pattern of the first alignment pattern outside the first target plane to deviate from the predetermined reflection pattern based on the convergence,
• an alignment imaging apparatus of an imaging arrangement, the alignment imaging apparatus being configured to capture an image of a reflection of the alignment light from the posterior surface of the crystalline lens on the first target plane;
• an examination imaging apparatus of the imaging arrangement, the examination imaging apparatus being configured to receive a reflection of the illumination light from the interior part of an eye through a reception path which has a reception waist at a third plane, the illumination path and the reception path of the examination imaging apparatus being separated from each other at and between the second and third planes, which are between the first target plane and the ophthalmic apparatus;
• and
• a communication interface configured to output information on the reflection pattern of the first alignment pattern reflected from a posterior surface of the crystalline lens of the eye when the ophthalmic apparatus is directed toward the eye for guiding and/or controlling a user based on the reflection pattern of the first alignment pattern that is varying with the position of the posterior surface of the crystalline lens to find the working distance from the eye where the predetermined shape of the first alignment pattern is on said posterior surface.

An ophthalmic apparatus, comprising:

• an alignment arrangement for imaging of fundus of an eye with means for:
• outputting rays of alignment light of a first alignment pattern in a converging manner toward a first target plane,
• forming a predetermined reflection pattern of the first alignment pattern on said first target plane based on the convergence,
• causing the rays of the alignment light to have an alignment light waist zone that includes the first target plane based on the convergence, and
• causing a reflection pattern of the first alignment pattern outside the first target plane to deviate from the predetermined reflection pattern based on the convergence;
• a communication interface configured to output information on the reflection pattern of the first alignment pattern reflected from a posterior surface of the crystalline lens of the eye when the ophthalmic apparatus is directed toward the eye for guiding and/or controlling a user based on the reflection pattern of the first alignment pattern that is varying with the position of the posterior surface of the crystalline lens to find the working distance from the eye where the predetermined shape of the first alignment pattern is on said posterior surface;
• wherein the alignment arrangement is further configured to direct rays of light of a cornea alignment pattern in a converging manner toward a fourth target plane, the cornea alignment pattern having a difference in shape, structure and/or color on opposite sides of a division plane of the cornea alignment pattern, a normal of the division plane of the cornea alignment pattern being perpendicular to an optical axis of the alignment arrangement, or the alignment arrangement being configured to converge the alignment light of the cornea alignment pattern differently on opposite sides of the division plane of the cornea alignment pattern,
• form a predetermined shape of the cornea alignment pattern on said fourth target plane based on the convergence,
• cause the rays of the cornea alignment light to have a cornea alignment light waist zone that includes the fourth target plane based on the convergence,
• cause a shape of the cornea alignment pattern to deviate from the predetermined shape outside the fourth target plane, and cause the shape of the cornea alignment pattern on one side of the fourth target plane to be different from the shape of the cornea alignment pattern on the opposite side of the fourth target plane based on the convergence;
• and
• wherein the imaging arrangement is optically configured to be at a working distance from the eye for a capture of an image of an interior part of an eye at least at one location in a range from a crystalline lens to fundus of the eye in response to a formation of the predetermined shape of the cornea alignment pattern on a cornea of the eye, which indicates that the cornea of the eye is at the fourth target plane.