Study on Reduction Methods of Moiré Noise in Image Acquisition of Periodic Gray-Scale Pattern

Abstract

Creating valid digital images for display surfaces is vital for the quantification of display quality (defects, spots) for display devices. However, when imaging a spatially discrete display surface using individual acquisition elements, an acquisition moire appears in the acquisition image. In this paper the authors quantify the display acquisition image, then clarify how to find the acquisition moire from the dimensions of the display system and acquisition target using computations. Based on these results, the authors formulate a method for determining a pixel shift which inverts the moire phase in a pixel-shifted image. They then propose a method to compute the average in pixel units of gradations between a reference image and a pixel-shifted image given by a reference image and a pixel-shifted image created using the above method. Finally, they verify the effects of reducing the acquisition moire using simulations. © 2001 Scripta Technica, Syst Comp Jpn, 33(1): 27–37, 2002