An international comparison of surface texture parameters quantification on polymer artefacts using optical instruments

An international comparison of optical instruments measuring polymer surfaces with arithmetic mean height values in the sub-micrometre range has been carried out. The comparison involved sixteen optical surface texture instruments (focus variation instruments, confocal microscopes and coherent scanning interferometers) from thirteen research laboratories worldwide. Results demonstrated that: (i) Agreement among different instruments could be achieved to a limited extent; (ii) standardised guidelines for uncertainty evaluation of areal surface parameters are needed for users; (iii) it is essential that the performance characteristics (and especially the spatial frequency response) of an instrument is understood prior to a measurement

Novel design for an ultra high precision 3D micro probe for CMM applications

AbstractThe paper reports on the design and testing of several new piezoresistive ultra high precision 3D microprobes for the use in coordinate measuring machines (CMM). The microprobes are all composed of three primary components a piezoresitive sensing element and stylus with probing sphere. The sensing element consists of a bossed KOH-etched silicon membrane with diffused piezoresistors. Several designs were investigated to increase sensor sensitivity while improving the anisotropy of stiffness. The initial design used a Wheatstone bridge piezoresistor configuration with a solid sensing membrane. Additionally, apertures where added to the solid silicon membrane to increase stress within the piezoresistors which untimely led to higher probe tip sensitivity. To improve the stiffness in the xy direction of the probe tip a double triangle design was tested that bonded two sensor chips back to back. This was found reduce the ratio between the stiffness in xy- and z-direction from 32 initially to 2

T is associated with severe dyspepsia

Contains fulltext : 96333.pdf (publisher's version ) (Open Access

Final report on EUROMET.L-S15.a (EUROMET Project 925): Intercomparison on step height standards and 1D gratings

SUPPLEMENTARY COMPARISON Measurements have been made at five national metrology institutes (NMIs) in the subject field of dimensional measurement using scanning probe microscopy. Four of the participating NMIs are in Europe, the fifth is in the Asia-Pacific region. Each NMI made measurements of four step height standards and two 1D grating standards. These are typical artefact standards used for dimensional nanometrology. Each participant used a different atomic force microscope to perform the measurements. The report lists the results obtained by the individual participants, as well as an analysis of the results and their uncertainties, based on calculation of the weighted means and En values. The results are in good agreement with one another