Leica X1 has a
12.0MP APS-C (23.6 x 15.8 mm ) sized CMOS sensor . On the other hand, Panasonic LX100 has a
13.0MP Four Thirds (17.3 x 13 mm ) sized CMOS sensor and features Venus Engine processor.
Below you can see the X1 and LX100 sensor size comparison.
As seen above, Leica X1 has a 1.7x Larger sensor area than Panasonic LX100. 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.