The application of a novel linear tricolor sampling leaf-shape grating to onestep in formation recording on a monochrome film is proposed. In this paper, it is proved that the proposed application can make the recording and retrieving simple and economical to implement, the color-cross-talk, Moire fringes and marginal loss in resolution avoided, the mutual modulation cleared up, the utilization ratio of light energy improved greatly.A method of computer generating the linear tricolor sampling leaf- shape grating is presented and the potential application to holography and optical information processing is also discussed.