When applied to the measurement of smooth surfaces, coherence scanning interferometry can be described by a three-dimensional linear filtering operation that is characterized either by the point-spread function in the space domain or equivalently by the transfer function (TF) in the spatial frequency domain. For an ideal, aberration-free instrument, these characteristics are defined uniquely by the numerical aperture of the objective lens and the bandwidth of the illumination source. In practice, however, physical imperfections such as those in lens aberrations, reference focus, and source alignment mean that the instrument performance is not ideal. Currently, these imperfections often go unnoticed as the instrument performance is typically only verified using rectilinear artifacts such as step heights and lateral grids. If an object of varying slope is measured, however, significant errors are often observed as the surface gradient increases. In this paper, a new method of calibration and adjustment using a silica micro-sphere as a calibration artifact is introduced. The silica microsphere was used to compute the point-spread and TF characteristics of the instrument, and the effect of these characteristics on instrument performance is discussed. Finally, a straightforward method to correct for phase and amplitude imperfections in the TF is described using a modified inverse filter.

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Adoption of international and U.S. financial accounting standards by leading German corporations presages a new era in European capital markets, with important implications for the design and management of German supplementary pensions. In this paper, we first introduce financial accounting standards boards, the evolution of U.S. pension accounting standards since ERISA (1974), and the introduction of FASB 87. We emphasize the quiet campaign by national and international accounting professionals to harmonize corporate accounting and the measurement of pension liabilities to accepted international standards. Using data collected from 1998 annual reports for German firms in the DAX 30 index, we report on and explain the adoption of international accounting standards by large German firms. This takes us to an analysis of the scope and significance of corporate pension liabilities. Noting the connection between accounting standards and global capital markets, we identify the implications of harmonization of German supplementary pension and retirement benefit systems for the mechanisms of financing benefits, the valuation of assets and liabilities, and the advantages and disadvantages of defined benefit as opposed to defined contribution plans. In combination, we show that historical differences between the Anglo-American system of corporate governance and the German system of entrenched management within interlocking boards of supervision and the representation of stakeholders' interests are now less compelling than assumed.

Coherence Scanning Interferometry (CSI), which is also referred to as scanning white light interferometry, is a well-established optical method used to measure the surface roughness and topography with sub-nanometer precision. One of the challenges CSI has faced is extracting the interfacial topographies of a thin film assembly, where the thin film layers are deposited on a substrate, and each interface has its own defined roughness. What makes this analysis difficult is that the peaks of the interference signal are too close to each other to be separately identified. The Helical Complex Field (HCF) function is a topographically defined helix modulated by the electrical field reflectance, originally conceived for the measurement of thin film thickness. In this paper, we verify a new technique, which uses a first order Taylor expansion of the HCF function to determine the interfacial topographies at each pixel, so avoiding a heavy computation. The method is demonstrated on the surfaces of Silicon wafers using deposited Silica and Zirconia oxide thin films as test examples. These measurements show a reasonable agreement with those obtained by conventional CSI measurement of the bare Silicon wafer substrates.