The ability to remove lenses darkened by cloudy imperfections, known as cataracts, and replace them with artificial lenses, is more than half a century old.

移除由于混浊的瑕疵而变暗的晶体，通常叫做白内障，然后用人工晶体替换它们，这种技术已经存在超过半个世纪。

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In 2006, and again in 2008, TLS was updated to remove these imperfections.

在2006年及2008年TLS曾两度升级以消除瑕疵。

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