Determination of small angular displacement by moiré fringes of matched radial-parallel gratings

摘要

We investigate the properties of the moiré fringes of matched radial-parallel (MRP) gratings that useful for the fine visual indication of angular displacements. Moiré patterns formed by overlapping two different MRP gratings of angular pitches, P↓（θ） and P↑(′)↓(θ) (