The techniques for shape measurement of 3-D object have widely been applied. Both moire topography and modified lighting technique have many advantages such as non-contact, high accuracy and high speed. But they inevitably meet with some difficulties, such as shadow noise and low contrast for measuring large object. Considering the correlation between two patterns sampled from the same object, a frigne-pattern connection method based on MAOST is proposed which can be effectively used to measure 3-D shape of large objects without all difficulties happened in conventional techniques. Mathematical mode, computer simulation and experimental results are presented.