CAMBRIDGE, UK, March 15 -- Polatis, developer of ultralow-loss photonic switches, has secured its second-round funding, raising $8.4 million. The investment round was led by Prelude Trust in addition to existing investors Alta Berkeley, 3i and new investor EonTech Ventures. Polatis raised a first-round investment package of $3m in December 2000, which enabled it to develop its Micro Actuation Sensing System and its market-leading product, the