US Patent No. 10,363,711

METHOD OF MAKING CONTACT LENSES


Patent No. 10,363,711
Issue Date July 30, 2019
Title Method Of Making Contact Lenses
Inventorship Gary Colin Miller, Southampton (GB)
John Haldyn Clamp, Cambridge (GB)
David John Clark, Hampshire (GB)
Phillip James Maine, Hampshire (GB)
Jonathan Andrew Lindley Blaine, Southampton (GB)
Assignee CooperVision International Holding Company, LP, St. Michael (BB) Contact L...

Claim of US Patent No. 10,363,711

1. A method of making a contact lens, the method comprising:(i) providing a first master mould for producing a first mould half and a second master mould for producing a second mould half;
(ii) producing at least one precursor mould comprising the first mould half and the second mould half, wherein the first mould half is for providing a first lens surface having at least one optical feature and the second mould half is for providing a second lens surface which requires lathing to provide at least one added optical feature;
(iii) producing a moulded precursor contact lens in each of the at least one precursor mould, wherein the step of producing the lens results in at least one identifiable undesirable attribute;
(iv) identifying the at least one undesirable attribute on the moulded precursor contact lens;
(v) determining the extent of the at least one undesirable attribute;
(vi) providing at least one lens producing mould formed from the first master mould and second master mould, each lens producing mould having a first mould half and a second mould half, wherein the first mould half is for providing a first lens surface having at least one optical feature and the second mould half is for providing a second lens surface which requires lathing to provide at least one added optical feature;
(vii) producing the contact lens in at least one lens producing mould;
(viii) removing the second mould half, whereby the contact lens remains positioned on the first mould half; and
(ix) lathing the second lens surface using a lathe tool, wherein the path of the lathe tool is controlled by a computer programme, and wherein the computer programme adjusts the path to compensate for the undesirable attribute of the moulded precursor contact lens identified in step (iv),
wherein the at least one undesirable attribute comprises an eccentricity of the precursor test contact lens from the centre of the of the mould half, and the eccentricity is characterized by defining an angle and magnitude of offset.