Patent Document ID: 9036900
Application ID: 13980775
Patent Status: 1

Claim One:
1. A method for measuring a three-dimensional shape comprising the steps of: a projection step for projecting an interference fringe pattern (F) having a single spatial frequency (fi) onto an object surface; a recording step for recording the interference fringe pattern (F) projected on the object surface by the projection step as a hologram using a photo detector; and a measurement step for generating a plurality of reconstructed images having different focal distances from the hologram recorded by the recording step, and deriving a distance to each point on the object surface by applying a focusing method to the interference fringe pattern (F) in each of the reconstructed images, wherein the measurement step comprises an interference fringe pattern extraction step for extracting a component of the single spatial frequency (fi) corresponding to the interference fringe pattern from each of the reconstructed images by spatial frequency filtering when the focusing method is applied.