Panasonic FX48 has a
12.0MP 1/2.3-inch (6.08 x 4.56 mm ) sized CCD sensor . On the other hand, Sony H55 has a
14.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor and features Bionz processor.
Below you can see the FX48 and H55 sensor size comparison.
Panasonic FX48 and Sony H55 have almost the same sensor size, so neither of them has any significant advantage over the other in terms of providing control over depth of field when used with the same focal length and aperture.