Nikon L31 has a
16.0MP 1/2.3' (6.17 x 4.55 mm ) sized CMOS sensor . On the other hand, Ricoh GXR A12 50mm has a
12.0MP APS-C (23.6 x 15.7 mm ) sized CMOS sensor and features GR engine III processor.
Below you can see the L31 and GXR A12 50mm F2.5 Macro sensor size comparison.
As seen above, Ricoh GXR A12 50mm has a 13.2x Larger sensor area than Nikon L31. 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.