Methods and systems for measuring image quality
Methods and systems for measuring the asymmetrical image quality or image features of an intraocular lens (IOL), design, refractive and diffractive designs, such as IOLs with Extended tolerance of astigmatic effects are provided by through-focus and meridian response. Measurements are taken at various focal plane and meridian positions to allow for determination of areas of better performance away from 0 meridian or the start position and meridian.
1. A method for evaluating performance of an asymmetric lens, comprising:
determining an initial focal plane position with respect to the lens being measured, and an end focal plane position;
providing an image capture device in the initial focal plane position, wherein the image capture device has an initial rotation angle;
capturing a first image at the initial focal plane position;
changing the rotation angle and the focal plane position by an incremental amount;
capturing a second image;
repeatedly changing the rotation angle and the focal plane position of the image capture device and capturing subsequent images until the image capture device reaches the end focal plane position; and
determining a measure of asymmetric lens performance based upon the captured images.
2. The method of claim 1 , wherein the lens is an intraocular lens (IOL).
3. The method of claim 1 , wherein the changing of the rotation angle position of the image capture device with respect to the lens comprises rotating the image capture device relative to the lens.
4. The method of claim 1 , wherein the image capture device is positioned on a stage and wherein changing of the rotation angle position of the image capture device with respect to the lens comprises rotating the stage relative to the lens.
5. The method of claim 1 , wherein the changing of the rotation angle position of the image capture device with respect to the lens comprises rotating an image capture window angularly.
6. The method of claim 1 , wherein the changing of the rotation angle position of the image capture device with respect to the lens comprises changing the relative angular position of the image capture device with respect to the lens by a predetermined angle.
7. The method of claim 6 , wherein the predetermined angle is 1 degree or less depending on the resolution of the image capture device.
8. The method of claim 1 , wherein the end focal plane position is 90 degrees relative angle of the image capture device with respect to the lens.
9. The method of claim 1 , wherein the initial focal plane position of the image capture device is 90 degrees relative angle of the image capture device with respect to the lens.
10. The method of claim 1 , wherein the image capture device is a charge coupled device (CCD).
11. The method of claim 1 , wherein the image capture device is one of a CCD, CMOS, film/light recording material, and a camera.
12. The method of claim 1 , wherein the changing of the focal plane position of the image capture device with respect to the lens comprises moving the image capture device.
13. The method of claim 1 , wherein the image capture device is positioned on a stage and wherein changing of the focal plane position of the image capture device with respect to the lens comprises rotating the stage relative to the lens.
14. The method of claim 1 , wherein the changing of the focal plane position of the image capture device with respect to the lens comprises moving the IOL or a stage holder hosting the IOL.
15. The method of claim 1 , wherein the changing of the focal plane position of the image capture device with respect to the lens is 20 microns or less depending on the resolution of the image capture device.