Scanner uncertainty

The traditional method of determining the position of an analyte spot on the plates is a visual evaluation. However, this technique is highly subjective and depends considerably on the expertise of the analytical chemist. TLC scanners, developed for exact determination not only pinpoint position but also the area, intensity and symmetry of the spot, overcome the uncertainty of the visual evaluation. Moreover, TLC scanners make possible more accurate determination of the quantity of analyte in the spot by converting spot characteristics into peak characteristics. Peak height is the distance between the peak maximum and the baseline, whereas peak area is the area of the peak between the beginning and end of the peak and the baseline. 

Intrinsic measurement error. In order to assess the accuracy of the blue light projection scanner Comet LSD represented in Fig. 1. (a), several digitizations of gauge blocks are performed. The uncertainty of the block dimensions can be considered negligible compared to uncertainty of the equipment. 

M. Mahmud, D. Joannic, M. Roy, A. Isheil, J.F. Fontaine, 3D part inspection path planning of a laser scanner with control on the uncertainty, Computer-Aided Design. 43 (2011) 345-355. 

Uncertainty Assessment in Terrestriai Laser Scanner Measurements... 

Abstract. The essential purpose of this study is to develop the measurement procedures in order to evaluate the quality of the observations carried out using Terrestrial Laser Scanner (TLS) equipment. It tries, in addition, to estimate an uncertainty value that allows the users to know the reliability of the instrument measurements. The fundamental idea of this paper is to show the metrological control s need, and the quality of measure s evaluation for TLS equipment and to describe a working methodology, able to be reproducible, without the essential need of having a very complex infrastructure. 

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