Article

Determination of modulation transfer function of a printer by measuring the autocorrelation of the transmission function of a printed Ronchi grating

Photonic Research Group, Amikabir University of Technology, Hafez Street, Tehran, Iran.
Applied Optics (Impact Factor: 1.69). 03/2009; 48(4):725-9. DOI: 10.1364/AO.48.000725
Source: PubMed

ABSTRACT We show theoretically and verify experimentally that the modulation transfer function (MTF) of a printing system can be determined by measuring the autocorrelation of a printed Ronchi grating. In practice, two similar Ronchi gratings are printed on two transparencies and the transparencies are superimposed with parallel grating lines. Then, the gratings are uniformly illuminated and the transmitted light from a large section is measured versus the displacement of one grating with respect to the other in a grating pitch interval. This measurement provides the required autocorrelation function for determination of the MTF.

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