May 30 2008
The National Physical Laboratory (NPL) has a new addition to its family of coordinate measuring machines (CMMs): the Zeiss F25. The F25 extends NPL’s coordinate measurement capability down to the micro-scale.
F25 probe next to 8mm reference sphere.
NPL has recently taken delivery of a Zeiss F25 Micro-CMM. System commissioning and operator training are complete and the CMM is now available for customer measurements. The F25 has been developed to facilitate the measurement of miniature components and is capable of accurate, 3D measurements of complex, precision-engineered components within a working volume of 100 mm x 100 mm x 100 mm.
The F25 is equipped with both a touch and an optical probe located on the same probe head. The design of the touch probe is based upon a silicon chip membrane and integrated piezo-resistive elements, and the integrated probe stylus is fitted with a precision ball tip. This measurement system, combined with ultra-precise machine kinematics, enables the F25 to achieve a measuring uncertainty of 250 nm at a resolution of 7.5 nm. This novel touch sensor technology also allows the probe to operate with very low probing forces, of the order of 0.5 mN. The touch probing system is designed for probe styli with ball tip diameters of 125 m to 700 m and with stylus lengths of up to 4 mm.
The F25 optical probing system comprises a ViScan camera sensor combined with a high quality objective lens. The optical sensor can provide 2D measurements with a measurement uncertainty of 400 m and allows the measurement of pliable and delicate components.
The F25 comes equipped with measurement software to allow the operator to perform a wide range of measurement tasks on standard geometric forms or freeform surfaces using a variety of measurement strategies. Applications include diesel injection nozzles, complex moulding tools, highly aspheric or freeform optics, and high aspect ratio microstructures.
The F25 is just one instrument in the suite of state-of-the-art measurement systems provided in support of the CEMMNT (Centre of Excellence in Metrology for Micro and Nano Technologies) partnership. NPL is currently carrying out research into reducing the size of the probing sphere to allow measurement of even smaller structures.