A new approach to the extraction of phase data from interferometric fringe patterns

It is shown that the single phase step technique has some definite advantages over those using more phase steps. It gives a computationally simple solution for 0(x,y) performed at greatly increased speed utilising an 8-bit look-up table. Only one phase step is required which practically eliminates environmental drift errors, which is especially important at the data acquisition stage. Because it needs only two phase shifted interferometric fringe patterns, the image memory required to store the data is reduced by a factor of 3. The reduced environmental and error sensitivity is ideal for fringe processing in industrial applications, this being enhanced by the use of pulsed laser illumination