The cascaded Talbot-Lau interferometer is formed by the serial combination of a Talbot-Lau and an inverse Talbot-Lau device，eliminating the need for fabricating small-period absorption gratings．Based on the constraints of the cascaded setup，it show that when the self-imaging fringe period larger than 210 μm，the detector can directly resolve the fringes，thereby omitting the need for an analyzer grating．Only a small-period phase grating needs to be fabricated．For the fabrication of the small-period phase grating，a metal nanoparticle with a solution as the carrier into the grating grooves．By comparing the effects of different modifiers on grating filling efficiency using scanning electron microscopy，it was found that oleic acid and N-methylpyrrolidone (NMP)provided more uniform and dense filling compared to OP-10，though nanoparticle aggregation was observed．The grating fabricated with the assistance of a suspension prepared by mixing N-methylpyrrolidone and isopropanol in a ratio of 0．25 mL 100 mL demonstrated the optimal performance．