Non-linearity and related features of Makyoh (magic-mirror) imaging

Non-linearity in Makyoh (magic-mirror) imaging is analysed using a geometrical optical approach. The sources of non-linearity are identified as (1) a topological mapping of the imaged surface due to surface gradients, (2) the hyperbolic-like dependence of the image intensity on the local curvatures, and (3) the quadratic dependence of the intensity due to local Gaussian surface curvatures. Criteria for an approximate linear imaging are given and the relevance to Makyoh-topography image evaluation is discussed. (paper)