Contact lens inspection system
A contact lens inspection system, in particular for soft contact lenses, comprises a light source ( 40 ) for illuminating a contact lens to be inspected; a plenoptic camera ( 1 ) for producing an electronic plenoptic image; a processing unit ( 103 ) adapted for electronically processing the electronic plenoptic image of the contact lens and configured for refocusing the image.
1. A method for inspecting a contact lens, the method comprising:
illuminating a contact lens to be inspected;
generating an electronic plenoptic image by a plenoptic camera ( 1 ) comprising different views of a contact lens field received by the photodetector ( 13 ), which is a Charge-Coupled Device (CCD) array; and
electronically processing the electronic plenoptic image of the contact lens to produce a final image by using different views of the contact lens field to adjust a plane-of-focus;
wherein generating the electronic plenoptic image by the plenoptic camera ( 1 ) comprises
receiving light from a contact lens, particularly arranged on a lens holder, at a lenslet array ( 11 ) comprising optical elements and located between an objective lens ( 10 ) and a photodetector ( 13 ) of the plenoptic camera, wherein each optical element in the lenslet array ( 11 ) receives light from the contact lens field from a different angle than the other optical elements in the lenslet array ( 11 ) and directs a different view of the contact lens field onto the photodetector ( 13 ); and
receiving light from the lenslet array ( 11 ) at a photodetector ( 13 ), wherein the photodetector ( 13 ) receives a different view of the contact lens field from each optical element in the lenslet array ( 11 ); and
further wherein the final image has a plane of focus arranged along a curved surface of the contact lens.