Device for automatically detecting characteristics of an ophthalmic lens and an automatic device for fitting a centering and drive peg incorporating it

1. A device for automatically detecting characteristics of an ophthalmic lens, comprising:

a support shaped to receive a lens and,

on respective opposite sides of said support,

i) an illumination system including an optical system for producing a light beam directed toward a lens on said support and, ii) a system for analyzing the image transmitted by said lens on said support,

wherein, said optical system defines two alternate optical paths for said light beam, and

a mask is placed on one only of said paths at a location such that it occupies a predetermined position relative to an optical axis of said analysis system and the other path is exempt from any mask.

2. The device claimed in claim 1 wherein said two optical paths have a common part on the upstream side of said support.

3. The device claimed in claim 1 wherein said illumination system includes at least two alternate light sources respectively corresponding to said two optical paths.

4. The device claimed in claim 3 wherein a first of said two light sources is a point source associated with a lens adapted to generate a parallel beam illuminating said mask.

5. The device claimed in claim 3 wherein a second of said two light sources is adapted to illuminate said lens on said support via a portion of said optical system excluding said mask.

6. The device claimed in claim 2 wherein said second light source is associated with a semireflecting mirror inserted between said mask and said support and materializing the intersection of said two optical paths.

7. The device claimed in claim 6 , wherein said second source is a point source associated with a lens adapted to generate a parallel beam directed toward said mirror.

8. The device claimed in claim 6 including an expander between said mirror and said support.

9. The device claimed in claim 3 including a third light source at the periphery of said support to illuminate a lens on said support at grazing incidence.

10. The device claimed in claim 1 wherein said analysis system includes a frosted translucent screen perpendicular to said optical axis between said support and an optical receiver.

11. The device claimed in claim 10 wherein said frosted translucent screen is adapted to be driven in rotation about an axis parallel to and spaced from said optical axis.

12. The device claimed in claim 10 wherein said optical receiver is a matrix sensor or a video camera.

13. A device for automatically detecting characteristics of an ophthalmic lens, comprising:

a support shaped to receive a lens and,

on respective opposite sides of said support, i) an illumination system including an optical system for producing a light beam directed toward a lens on said support and, ii) a system for analyzing the image transmitted by said lens on said support,

wherein said optical system defines two alternate optical paths for said light beam and a mask is placed on one only of said paths at a location such that it occupies a predetermined position relative to an optical axis of said analysis system, and said mask is disposed on the upstream side of said support with respect to the direction of said light beam.

14. A device for automatically positioning a centering and drive peg on an ophthalmic lens, including a device for automatically detecting characteristics of an ophthalmic lens, comprising

a support shaped to receive a lens and,

on respective opposite sides of said support, i) an illumination system including an optical system for producing a light beam directed toward a lens on said support and, ii) a system for analyzing the image transmitted by said lens on said support,

wherein said optical system defines two alternate optical paths for said light beam and a mask is placed on one only of said paths at a location such that it occupies a predetermined position relative to an optical axis of said analysis system.

15. The device claimed in claim 14 including a controlled mobile positioning mechanism including an arm for positioning said peg adapted to engage in a space left free in the vicinity of said support.

16. The device claimed in claim 15 wherein said arm for positioning said peg includes a controlled rotary shaft at the end of which a centering and drive peg can be mounted.

17. The device claimed in claim 16 wherein said positioning mechanism can move said positioning arm along three orthogonal axes.

18. The device claimed in claim 1 , wherein the mask forms a Hartmann matrix.

19. The device claimed in claim 13 , wherein the mask forms a Hartmann matrix.

20. The device claimed in claim 14 , wherein the mask forms a Hartmann matrix.