Thermo Fisher Scientific Inc. (NYSE:TMO) has about $938 million to spend on buying back its own stock, after its board of directors added another $750 million to the kitty.

That’s on top of the $188 million remaining on a previous stock repurchasing authorization, according to a press release.

That plan was set to expire next April; the latest authorization is good until September 8, 2011, Thermo Fisher said.

Last month the Waltham, Mass.-based lab instruments maker announced plans to shutter its operation in Rhode Island, only to open another in mainland China. Thermo Fisher said it plans to close its disease diagnostics-focused business in East Providence, R.I., in June 2011, laying off 65 workers and merging the operation with others in Virginia and Texas.

Later in August the company announced the debut of a technology center in Shanghai, aimed at serving its life science, environmental monitoring and consumer product safety businesses in China.