FEI Co., Hillsboro's rapidly growing electron microscope manufacturer, reported Monday that it has purchased a German microscope company for about $20 million.

TILL Photonics makes microscopes and other technology for studying live cells. Life sciences are the fourth-largest portion of FEI's business, but it's expanding rapidly -- third-quarter revenues in that segment totaled $30.2 million, up 65 percent from the prior year. They now account for about 15 percent of FEI's total business.

FEI said TILL will add about $8 million in revenue this year.

"With this acquisition, FEI acquires additional key technology for correlative microscopy for cellular biology, which integrates high-performance light and electron microscopy," said Don Kania, FEI's chief executive, in a written statement.

FEI's stock fell 47 cents this morning to $39.60. The company's stock has been trading near an all-time high following several quarters of rapidly growing sales and profits.

-- Mike Rogoway; twitter: @rogoway; phone: 503-294-7699

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