Methods and devices for testing torsional alignment between a diagnostic device and a laser refractive system

1 . A method comprising:

positioning a test device in an optical axis of the diagnostic device in a first orientation;

obtaining a first image of the test device with the diagnostic device;

positioning the test device in an optical axis of a laser refractive system in a second orientation that is torsionally offset from the first orientation so as to provide a known torsional misalignment;

obtaining a second image of the test device with the laser refractive system;

measuring a torsional misalignment of the test device in the first image and the test device in the second image; and

comparing the measured misalignment with the known misalignment to determine the accuracy of the measured misalignment.

2 . The method of claim 1 wherein the diagnostic device comprises an aberrometer.

3 . The method of claim 2 wherein the aberrometer comprises a Hartmann-Shack device, Tscheming device, or a ray tracing device.

4 . The method of claim 2 wherein the aberrometer comprises a wavefront measurement sensor.

5 . The method of claim 1 wherein positioning the test device within the optical axis comprises coupling the test device to a head rest.

6 . The method of claim 1 wherein comparing the first image of the test device to the second image of the test device comprises determining a cyclotorsional rotation between the first image and the second image.

7 . The method of claim 1 wherein the test device comprises a proximal portion that defines a radiused corneal surface and an iris, and a distal portion that defines a retinal surface.

8 . The method of claim 1 wherein the test device is positioned within the optical axes of at least one of the diagnostic device and the laser refractive system with a holder.

9 . The method of claim 1 wherein the test device has visual and optical characteristics of a human eye.

10 . A method comprising:

providing a test device comprising a corneal surface, an iris and a retinal surface in a first orientation with the diagnostic device;

obtaining a first image of the test device with the diagnostic device;

obtaining a second image of the test device that is positioned in a second orientation with the laser refractive system; and

comparing the first image of the test device to the second image of the test device to measure a torsional misalignment between the test device in the first orientation and the test device in the second orientation; and

determining an accuracy of the measured misalignment by comparing the measured misalignment to a known misalignment.

11 . A test device for testing an alignment measurement between a diagnostic device and a laser refractive system, the device comprising:

a body comprising a proximal portion and a distal portion;

wherein the proximal portion defines a corneal surface and an iris, and the distal portion defines a retinal surface.

12 . The device of claim 11 wherein the corneal surface is radiused.

13 . The device of claim 11 wherein the iris surface comprises one or more texture patches.

14 . The device of claim 11 wherein the retinal surface defines a diffuse surface.

15 . The device of claim 14 wherein the diffuse surface absorbs light.

16 . The device of claim 11 wherein the test device defines a visible pupil diameter between about 3 mm and about 8 mm.

17 . The device of claim 11 wherein the body comprises a material that disperses different wavelengths of light at a substantially same rate as a human eye.

18 . The device of claim 17 wherein the material comprises polymethylmethacrylate (PMMA) or glass.

19 . The device of claim 11 wherein the body further comprises an alignment reference.

20 . The device of claim 19 wherein the alignment reference comprises an alignment pin that extends radially from a longitudinal axis of the body.

21 . The device of claim 19 wherein the alignment reference comprises a flattened surface along at least one of the proximal portion and distal portion of the body.

22 . A device that tests alignment between a diagnostic device and a laser refractive system, the device comprising:

a body;

means for providing optical alignment markers; and

means for providing a retinal surface.

23 . A method of manufacturing a test device, the method comprising:

providing a body that comprises a first optical surface and a second, radiused optical surface;

treating the body to form a textured annular iris surface;

treating the first optical surface to create a pupil surface.

24 . The method of claim 23 wherein treating the body comprises creating a unique pattern of striations and imperfections.

25 . The method of claim 23 wherein treating the first optical surface comprises:

polishing the first optical surface to produce a diffuse back scattering surface; and

applying a material that absorbs light to the polished surface.

26 . The method of claim 25 wherein polishing is carried out with 0.3 micron Al 2 O 3 grit.

27 . The method of claim 25 wherein the material comprises a flat dark gray paint.

28 . A kit for testing an alignment between a diagnostic device and a laser refractive system, the kit comprising:

a test device;

instructions for use comprising placing the test device in a first orientation and obtaining a first image of the test device with the diagnostic device, placing the test device in a second orientation that is torsional offset from the first orientation, obtaining a second image of the test device with the laser refractive system, and comparing a known torsional misalignment between the test device with a measured torsional misalignment that is calculated by comparing the first image of the test device to the second image of the test device; and

a package to hold the test device and instructions for use.

29 . The kit of claim 28 wherein the test device comprises a body comprising a proximal portion and a distal portion, wherein the proximal portion defines a corneal surface and an iris, and the distal portion defines a retinal surface.

30 . The kit of claim 28 wherein the body further comprises an alignment reference.

31 . The method of claim 1 wherein the measured misalignment is carried out with a cyclotorsional measurement algorithm.

32 . The method of claim 31 further comprising calibrating the cyclotorsional measurement algorithm based on a difference between the measured misalignment and the known misalignment.