Intensity diffraction tomography (IDT) is an imaging method for reconstructing the complex refractive index distribution of a weakly scattering three-dimensional object. Unlike classic diffraction tomography, which requires measurement of the transmitted wave-field phase, IDT accomplished this reconstruction from knowledge of wave-field intensity measurements on parallel detector planes at each tomographic view angle. In this work, novel scanning protocols and reconstruction algorithms for IDT are proposed that require two intensity measurements on a single detector plane positioned at a fixed distance from the object. Each measurement corresponds to a probing spherical wave field that possesses a distinct curvature. Accordingly, the form of the incident wavefield, rather than the detector position, represents the degree of freedom in the imaging system that is varied for acquisition of the necessary measurement data. Computer simulation studies are conducted to investigate the developed data acquisition and image reconstruction algorithms.