MIDDLEFIELD CT-Technology manufacturerZygo Corp. landed a $3.5 million order from China for a set of its high-end optical testing systems. The order is a result of a two-year-old joint venture Zygo has with its Shanghai partner.

While Zygo has not named the Chinese customer buying its laser interferometers-which are big enough to test large-scale optical components-it said the customer insisted Zygo and one other unnamed competitor meet strict technical requirements.

All the components will be manufactured and assembled in Middlefield, and will be delivered to China in mid-2011, the company said.