Purkinje meter and method for automatic evaluation

1. A device for automatically detecting the position of an intraocular lens or a natural lens in an eye, comprising:

a camera comprising a camera lens and a camera axis;

a positioning unit adapted to bring the camera relative to the eye to be imaged in a fixed, predetermined position;

a plurality of individual light sources, which are arranged so that each of the light sources can emit light beams at a respective predetermined angle with respect to the camera axis and in the direction of the eye to be imaged; and

a control unit which is configured with a constant position of the camera and the light sources, to capture an image sequence of the eye to be imaged and to secure said sequence on a non-transitory storage medium;

wherein the control unit is configured to switch the light sources on and off so that during capture of the images, the light sources are turned on in a predetermined order and that during the capture of each of the images only one predetermined light source is turned on;

wherein the control unit is further configured to recognize individual imaged light reflections and their displacement along the image sequence; assign at least one of the light reflections to a Purkinje-reflex by a recognized shape and the displacement of the corresponding light reflections and the predetermined angle of the respectively corresponding light source, which was switched on during the capture of a respective image; and calculate the decentration and/or tilt of the lens based on the assigned Purkinje reflexes; and

wherein the light sources are arranged around the camera lens along at least one arc of circle.

2. The device according to claim 1 , wherein the light sources are arranged on an annular surface, or partial annular surface, obliquely oriented to the camera axis.

3. The device according to claim 1 , wherein the light sources are infrared light emitting diodes and wherein the camera comprises an infrared sensitive imaging sensor.

4. The device according to claim 1 , wherein the light sources are arranged on a support plate.

5. The device according to claim 4 , wherein the device comprises:

a single visually recognizable reference point.

6. The device according to claim 5 , wherein the single visually recognizable reference point is on the support plate.

7. The device according to claim 5 , wherein the support plate comprises:

an additional light source capable of emitting visible light.

8. The device according to claim 7 , wherein the additional light source is arranged to be turned on during the detection of each of the images.

9. The device according to claim 1 , wherein the device additionally comprises:

a processing unit which is adapted to recognize on the images of the image sequence individual imaged light reflections, and their displacement along the image sequence.

10. A method for automatically detecting the position of an intraocular lens or a natural lens in an eye on the basis of an image sequence,

the method comprising:

continuous focusing by an eye of a single visually recognizable reference point during a capturing of an image;

recognition of individual imaged light reflections and their displacement along an image sequence;

assigning at least one of the light reflections to a Purkinje-reflex by a recognized shape and the displacement of the corresponding light reflections and a predetermined angle of the respectively corresponding light source, which was switched on during the capture of a respective image;

switching the light sources on and off so that during capture of the images, the light sources are turned on in a predetermined order and that during the capture of each of the images only one predetermined light source is turned on; and

calculating the decentration and/or tilt of the lens based on the assigned Purkinje reflexes.

11. The method according to claim 10 , further comprising:

automatically recognizing an outline of the pupil and/or iris of the imaged eye in the image sequence.

12. A device for automatically detecting the position of an intraocular lens or a natural lens in an eye, comprising:

a camera comprising a camera lens and a camera axis;

a positioning unit adapted to bring the camera relative to the eye to be imaged in a fixed, predetermined position;

a plurality of individual light sources, which are arranged so that each of the light sources can emit light beams at a respective predetermined angle with respect to the camera axis and in the direction of the eye to be imaged; and

a control unit which is configured with a constant position of the camera and the light sources, to capture an image sequence of the eye to be imaged and to secure said sequence on a non-transitory storage medium;

wherein the control unit is configured to switch the light sources on and off so that during capture of the images, the light sources are turned on in a predetermined order and that during the capture of each of the images only one predetermined light source is turned on; and

wherein the control unit is further configured to recognize individual imaged light reflections and their displacement along the image sequence; assign at least one of the light reflections to a Purkinje-reflex by a recognized shape and the displacement of the corresponding light reflections and the predetermined angle of the respectively corresponding light source, which was switched on during the capture of a respective image; and calculate the decentration and/or tilt of the lens based on the assigned Purkinje reflexes; and

wherein the light sources are arranged on a support plate; and

wherein the device further comprises a single visually recognizable reference point on the support plate.