Leica X1 has a
12.0MP APS-C (23.6 x 15.8 mm ) sized CMOS sensor . On the other hand, Nikon S1100pj has a
14.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor and features Expeed C2 processor.
Below you can see the X1 and S1100pj sensor size comparison.
As seen above, Leica X1 has a 13.3x Larger sensor area than Nikon S1100pj. Larger sensors give photographer more control on the depth of field and blurry background compared to smaller sensor when shot in same focal length and aperture.