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A 3-D optical whole-field profilometer based on adaptive projection of structured light is presented. The system is based on the projection of gratings by means of an LCD unit. The gratings can be varied both in contrast and in period, to adapt to the shape of the object under measurement. A video camera acquiresat a different angle the object-deformedpattern. Suitable pre-elaboration is performed, to decrease dependence on background illumination and nonuniform reflectivity of the surface. Adaptive demodulation of the pattern allows the object profile to be evaluated.\ud The performance of the instrument has been evaluated by means of a system calibration against a traceable high-precision commercial Contact Measuring Machine (CMM). The overall accuracy of the system is equal to 0.15 mm with a precision of 0.2 mm. In this article, the theoretical aspects of the technique are discussed,and the description of the complete system is presented. Profile reconstruction, calibration,and certificationof the system are also covered. The accuracy of the system is discussed, and experimental results are presented

The Optical Forward Scattering (OFS) technique can be used to identify pathogens by direct observation of bacteria colonies growing on a culture plate. The identification is based on the acquisition of scattering images from isolated colonies and their subsequent comparison with reference images acquired from known bacteria. The technique has been mainly studied for the identification of pathogens in the food-safety field. This paper focuses on the possibility of extending the applicability of the technique to the field of clinical laboratory automation. This scenario requires that the paradigm of image acquisition at fixed colony-dimension, well established in the food-safety applications, should be substituted by an acquisition at fixed incubation time. As a consequence, the scatterometer must be adjustable in real-time for adapting to the actual features of the bacterial colony. The paper describes an OFS system prototype qualified by the possibility to tune both the laser beam diameter and the acquisition camera field of view.Preliminary experiments on bacteria cultures from pathogens causing infections of the urinary tract show that the proposed approach is promising for the development of an Submitted to Biosensor and Bioelectronics 2 automated bacteria identification station. The new OFS approach also involves an alternative method for building a reference image database for subsequent image analysis.

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