TY  - JOUR
PY  - 1996//
TI  - Effects of coatings on the fracture resistance of ophthalmic lenses
JO  - Optometry and vision science
A1  - Corzine, J. C.
A1  - Greer, R. B.
A1  - Bruess, R. D.
A1  - Lee, G. K.
A1  - Scaief, A. L.
SP  - 8
EP  - 15
VL  - 73
IS  - 1
N2  - BACKGROUND: Scratch-resistant (SR) and anti-reflective (AR) coatings are commonly applied to plastic ophthalmic lenses. Fracture resistance is greatly affected by surface characteristics, and coatings may have a weakening effect. Static load testing is an efficient, quantifiable alternative to the drop ball test and has been suggested as useful for comparing lenses of a given material. METHODS: An Instron static load tester was used to test the fracture resistance of 140 CR-39 lenses divided into 4 groups: uncoated, prepared for AR coating but not actually coated, AR coated, and factory SR coated. RESULTS: Compared to the control uncoated group, AR coating reduced the required fracture energy by 63% and SR coating by 57%. Preparation for AR coating had no significant effect. CONCLUSIONS: These results are at least qualitatively consistent with drop ball testing and have significant implications as new plastic materials are developed, made thinner, and variously coated.<p /> <p>Language: en</p> 
LA  - en
SN  - 1040-5488
UR  - http://dx.doi.org/
ID  - ref1
ER  -