Based on the temporally and spatially mixed modulated polarization interference imaging spectrometer (TSMPIIS) developed by us, a novel mode for obtaining interferogram and spectrum is proposed. The interference data arrays acquired with this mode are analyzed, and the method for combining a series of interferograms at different moments is explained in detail. Furthermore, the interferograms of monochromatic light and polychromatic light obtained by TSMPIIS are processed. The satisfactory interferogram and reconstructed spectra show the superiority of this detection mode, such as wide field of view, high detection sensitivity and high throughput, etc.