Cemented lens and process for production thereof

Abstract

A cemented lens consists of a lens that is tinted and/or contains a UV absorber, and a second lens that is neither tinted nor contains any UV absorber. The cemented lens is formed by placing the two lens elements together with a UV-curable adhesive between them, and then directing UV radiation through the first lens to cure the adhesive.

What is claimed is: 
     
       1. A cemented lens, consisting of a first lens element that contains a UV absorber and a second lens element that does not contain a UV absorber. 
     
     
       2. A cemented lens according to claim 1, wherein said second lens element is positioned away from the eye. 
     
     
       3. The cemented lens of claim 1, wherein said first and second lens elements are bonded together with a UV-curable adhesive, which is cured with UV radiation projected through said second lens element which does not contain a UV absorber. 
     
     
       4. The cemented lens of claim 3, wherein said first lens element is tinted and said second lens element is not tinted. 
     
     
       5. A cemented lens according to claim 4, wherein said untinted lens element is positioned away from the eye. 
     
     
       6. A process for producing a cemented lens, comprising the steps of applying a UV-curable adhesive onto mating surfaces of a first lens element containing a UV absorber and a second lens element not containing a UV absorber, assembling the two lens elements and applying UV radiation to the assembly through the second lens element. 
     
     
       7. A process according to claim 6, wherein said second lens element is positioned away from the eye. 
     
     
       8. A process according to claim 6, wherein the untinted lens element is positioned away from the eye. 
     
     
       9. A process for producing a cemented lens, comprising the steps of applying a UV-curable adhesive onto mating surfaces of a tinted lens element, which contains a UV absorber and an untinted lens element, which does not contain a UV absorber, assembling the two lens elements and applying UV radiation to the assembly through the untinted lens element. .Iadd. 
     
     
       10.  A cemented lens according to claim 1, wherein said first lens element comprises polycarbonate resin or polyurethane resin. .Iaddend..Iadd.11. A cemented lens according to claim 1, wherein said second lens element comprises diethyleneglycol bisallylcarbonate polymer. .Iaddend..Iadd.12. A cemented lens according to claim 1, wherein a surface of said second lens element is a multi-focus surface, a progressive multi-focus surface, or an aspheric surface. .Iaddend..Iadd.13. A cemented lens according to claim 1, wherein said first lens element has a negative power. .Iaddend..Iadd.14. A cemented lens according to claim 13, wherein said second lens element comprises diethyleneglycol bisallylcarbonate polymer. .Iaddend..Iadd.15. A cemented lens according to claim 1, wherein said second lens element has a positive power. .Iaddend..Iadd.16. A cemented lens according to claim 1, further comprising a light-setting adhesive which bonds said first and 
     
     
        second lens elements. .Iaddend..Iadd.17.  A cemented lens according to claim 16, wherein said light-setting adhesive comprises a UV curable adhesive. .Iaddend..Iadd.18. A cemented lens comprising: a first lens located on a user's eye side of the cemented lens, said first lens comprising polycarbonate resin or polyurethane resin; and   a second lens located on an object side of the cemented lens, said front lens comprising a synthetic resin having a refractive index different from a refractive index of said rear lens, wherein only one of said first and second lenses contains a UV absorber. .Iaddend..Iadd.19. A cemented lens according to claim 18, wherein said second lens comprises diethyleneglycol bisallylcarbonate polymer. .Iaddend..Iadd.20. A cemented lens according to claim 18, wherein said first lens contains a UV absorber. .Iaddend..Iadd.21. A cemented lens according to claim 18, wherein a surface of said second lens element is a multi-focus surface, a progressive multi-focus surface, or an aspheric surface. .Iaddend..Iadd.22. A cemented lens according to claim 18, wherein said   
     
     
        first lens has a negative power. .Iaddend..Iadd.23.  A cemented lens according to claim 18, wherein said second lens has a positive power. .Iaddend..Iadd.24. A cemented lens according to claim 18, further comprising a light-setting adhesive which bonds said first and second lenses. .Iaddend..Iadd.25. A cemented lens according to claim 18, wherein said light-setting adhesive comprises a UV curable adhesive. .Iaddend.