Panasonic LX3 has a
10.0MP 1/1.63-inch (8.07 x 5.56 mm ) sized CCD sensor . On the other hand, Ricoh CX1 has a
9.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CMOS sensor and features Smooth Imaging Engine IV processor.
Below you can see the LX3 and CX1 sensor size comparison.
As seen above, Panasonic LX3 has a 1.6x Larger sensor area than Ricoh CX1. 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.