Based on the imaging theorem and different patial space-frequency characteristic of the kinoform , the kinoform has been sampled by frequency-change,ensuring that the same digitized grade should be taken in the phase difference from 0 to 2π or -π to π. In the way, the information redundancy of the kinoform that results from the sampling redundancy has been eliminated. Further more, a good reconstructed image can be acquired from restoration kinoform by the nearest interpolation. The feasibility and efficiency of the method are confirmed by theoretical analysis and experimental results. So a new thought has been offered for fast computation, the information storage and transmission of kinoform.