Optics and Lasers in Engineering 43 (2005) 951–962 Investigation of dynamic displacements of lithographic press rubber roller by time average geometric moire´ Minvydas Ragulskis a,Ã , Rimas Maskeliunas b , Liutauras Ragulskis c , Vytautas Turla b a Kaunas University of Technology, Department of Mathematical Research in Systems, Studentu 50-222, Kaunas LT-51368, Lithuania b Vilnius Gediminas Technical University, Department of Printing Machines, J. Basanaviciaus 28, Vilnius LT-03224, Lithuania c Vytautas Magnus University, Department of Informatics, Vileikos 8, Kaunas LT-44404, Lithuania Received 1 July 2004; received in revised form 1 October 2004; accepted 1 October 2004 Available online 24 December 2004 Abstract Geometric moire´ fringe formation method is a classical well-established experimental technique with numerous practical applications. This paper proposes the application of time- average geometric moire´ analysis for the determination of dynamic displacements of the lithographic press rubber roller. This optical measurement technique is a natural extension of double-exposure geometric moire´ for the identification of dynamic displacements of vibrating elastic structures. Experimental investigations prove the validity and effective practical applicability of the method. r 2004 Elsevier Ltd. All rights reserved. Keywords: Geometric moire´; Fringes; Time average; Vibration; Press roller ARTICLE IN PRESS 0143-8166/$ - see front matter r 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.optlaseng.2004.10.004 Ã Corresponding author. Tel.: +370 698 22456; fax: +370 373 30446. E-mail address: minvydas.ragulskis@ktu.lt (M. Ragulskis).