code is passed over a scanner, a laser beam scans across the bar code. The scattered light ismodulated by the reflectivity of the bars and spaces of the bar code. The bar code scanning processcan be described as a 1 -D convolution of the scanning laser profile and the bar code reflectivityfunction. The modulation transfer function (MTF) of bar code scanning is the Fourier transform of themarginal profile of the laser beam. The properties of the MTF of bar code scanning is similar to thatof an incoherent imaging system. Measurements of the MTF of bar code scanning at one focalposition are presented. The experimental results are then discussed.
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