The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In a two-wavelength phase-shifting speckle interferometer for object contouring one usually obtains only the height coordinate of the object surface which is parallel to the viewing direction (here denoted as z-coordinate). In order to measure the lateral surface coordinates x and y by the same technique the light source is shifted in two directions (denoted as u andv ) perpendicular to the optical axis. Two additional phase maps of parallel fringes are generated which are then used to assign the lateral coordinates x and y to the corresponding pixels of the camera. All the other advantages of two-wavelength interferometry remain unaffected.