A leading Oxford technology company has unveiled a major expansion after buying up an American rival.

Oxford Instruments Measurement Systems has taken over Chicago-based CMI International in a deal worth £1.7m.

Managers at the Eynsham-based firm, a wholly-owned subsidiary of Oxford Instruments, say they have invested in expertise that complements their own cutting-edge X-ray technology.

CMI, a 15-year-old privately-owned company, has grown into the market leader in the US for the design, manufacture, sale and service of instruments for the accurate measurement of thin metallic coatings.

The main industries CMI serves include electronic components, automotive, metal finishing, semiconductor, data storage, and vacuum coating.

The latest financial figures show CMI has a turnover of £6.5m, and Oxford Instruments aims to build CMI's business via its expertise in engineering, manufacturing and distribution.

Oxford Instruments chief executive Andrew Mackintosh said: "CNI is a business we have known for many years, which has an outstanding reputation and a leadership position in its market.

"The acquisition creates for us additional growth opportunities, both in CMI's customer base and for existing analytical instrumentation business."

Oxford Instruments is a leader in advanced instrumentation, including the application of superconductivity and the production and detection of X-rays.

Its customers include many of the world's leading hospitals and research institutes.

The company, which has a £185m annual turnover, employs more than 1,000 people worldwide, with about 800 based in Oxfordshire.