Custom eyeglass manufacturing method

• US 20040189935A1
• Filed: 01/13/2004
• Published: 09/30/2004
• Est. Priority Date: 10/25/2001
• Status: Active Grant

• Current Assignee: Essilor International SA
• Original Assignee: Enterprise Partners VI LP (Enterprise Partners Venture Capital)
• Inventors: Dreher, Andreas W., Warden, Laurence, Murphey, Tro
• Granted Patent: US 7,434,931 B2
• Time in Patent Office: Days
• US Class Current: 351/204
• CPC Class Codes: G02C 13/003 Measuring during assembly or fitting of spectacles
• CPC Class Codes: G02C 13/005 Measuring geometric parameters required to locate ophtalmic lenses in spectacles frames apparatus for testing or instruments for examining the eyes per se A61B3/00; machines or devices and accessories for grinding the edges of lenses using spectacles as a template B24B9/144
• CPC Class Codes: G02C 7/027 considering wearer's parameters

Abstract

Two or more images captured from digital cameras record an image of spectacle frames on a subject. The image is analyzed using automated image-processing techniques to identify the relation of specific points of interest on the frame to the location of each of the subject'"'"'s eyes allowing the optical center of the lens to be placed in the correct location in the frames.

Claims

1. A spectacle frame fitting system, the system comprising:

an imager configured to capture a front image and a side image of a subject field; and

an image processor configured to receive and analyze the front image and the side image to determine a pupil position relative to a spectacle frame captured in the front and side images.

2. The system of claim 1, further comprising a positioner configured to locate a position of a subject wearing the spectacle frame within the subject field.

3. The system of claim 1, further comprising a beam splitter positioned in an axis of the front image and configured to reflect the front image to the imager positioned off of the axis of the front image.

4. The system of claim 3, wherein the beam splitter is positioned substantially at a 45 degree angle relative to the axis of the front image and configured to reflect the front image to the imager having an imaging axis approximately 90 degrees from the axis of the front image.

5. The system of claim 1, wherein the imager comprises a first camera configured to capture the front image and a second camera configured to capture the side image.

6. The system of claim 5, wherein the first camera and second camera have substantially parallel imaging axis, and wherein the system further comprises a beam splitter configured to reflect the front image to the imaging axis of the first camera.

7. The system of claim 1, further comprising an illuminator configured to illuminate the subject when the imager captures the front image and the side image.

8. The system of claim 7, wherein the illuminator comprises a plurality of light sources configured to generate a predetermined pattern on a cornea of a subject positioned within the subject field.

9. The system of claim 8, wherein the image processor determines the pupil position based in part on the predetermined pattern.

10. The system of claim 7, wherein the illuminator comprises at least one colored light source.

11. The system of claim 7, wherein the illuminator comprises at least one light source that is selectively controlled on or off.

12. The system of claim 1, wherein the image processor is configured to determine a spatial distance in the front image.

13. The system of claim 1, wherein the image processor is configured to determine a spatial distance in the side image.

14. The system of claim 1, wherein the image processor determines the pupil position using image thresholding and connectivity analysis.

15. The system of claim 1, wherein the image processor determines a lens frame within the spectacle frame using edge analysis of the front image.

16. The system of claim 1, wherein the image processor determines a pantoscopic tilt based on edge analysis of the side view.

17. A spectacle frame fitting system, the system comprising:

an imager configured to capture a front image and a side image of a subject field;

a plurality of light sources configured to generate a predetermined pattern on a cornea within the subject field; and

an image processor configured to analyze the front image and the side image to determine a pupil position relative to a spectacle frame captured in the front and side images, based in part on the predetermined pattern.

18. The system of claim 17, wherein the imager is configured to capture an additional front image during a period in which at least one of the plurality of light sources is not illuminated.

19. A method of fitting a corrective lens to a spectacle frame, the method comprising:

capturing a front image of a subject wearing the spectacle frame;

capturing a side image of the subject wearing the spectacle frame;

determining a position of a lens frame from the captured images;

determining the position of at least one pupil of the subject from the captured images; and

determining a pupilary center of the corrective lens based in part on the position of the lens frame and the position of the pupil.

20. The method of claim 19, wherein determining the position of the lens frame comprises determining, using edge detection, the lens frame in the captured front image.

21. The method of claim 19, wherein determining the position of the lens frame comprises receiving information defining a box having at least one side tangential to an edge of the lens frame.

22. The method of claim 19, wherein capturing the front image of the subject comprises:

illuminating the subject with a plurality of lights to generate a pattern on at least one cornea of the subject; and

capturing the front image during the period in which the plurality of lights is illuminated.

23. The method of claim 19, wherein determining the position of at least one pupil comprises:

identifying at least one bright pixel on an image of a cornea of the subject;

identifying at least one dark pixel on the image of the cornea; and

identifying the pupil based in part on the relationship of the at least one dark pixel relative to the at least one light pixel.

24. The method of claim 19, wherein determining the position of at least one pupil comprises:

comparing the captured front image to a predetermined bright threshold to identify bright pixels;

performing connectivity analysis on the bright pixels to generate bright blobs;

filtering the bright blobs based in part on a size of the bright blob;

comparing the captured front image to a predetermined dark threshold;

performing connectivity analysis on the dark pixels to generate at least one dark blob;

filtering the at least one dark blob based on a size of the blob;

determining the position of the pupil based in part on a position of the filtered dark blobs and a position of the bright blobs.

25. The method of claim 19, further comprising:

capturing a front image of the subject without the spectacle frame; and

subtracting the front image of the subject without the spectacle frame from the front image of the subject wearing the spectacle frame to produce a difference image; and

wherein determining the position of the lens frame comprises determining the position of the lens frame from the difference image.

26. A spectacle frame fitting system, the system comprising:

an imager configured to capture a front image and a side image of a subject field;

a plurality of colored light sources configured to illuminate at least a portion of the subject field; and

an image processor configured to analyze the front image and the side image to determine a pupil position relative to a spectacle frame captured in the front and side images, based in part on the predetermined pattern.

27. The system of claim 26, wherein at least one of the colored light sources is configured to generate a fiducial mark within the subject filed and the image processor analyzes the front image in part based on the fiducial mark.

28. The system of claim 26, further comprising:

a first dichroic beam splitter configured to reflect the side image of the subject field to the imager; and

a second dichroic beam splitter configured to reflect the front image of the subject filed to the imager.

29. The system of claim 28, wherein the first dichroic beam splitter passes a wavelength of light that is different than the wavelength of light passed by the second dichroic beam splitter.

30. The system of claim 28, wherein the plurality of colored light sources comprises a first colored light source and a second colored light source, the first dichroic beam splitter configured to reflect wavelengths corresponding to the first colored light source and the second dichroic beam splitter configured to reflect wavelengths corresponding to the second colored light source.

31. The system of claim 30, wherein the camera captures successive images and each image corresponds to illumination with one of the plurality of colored light sources.