Samsung WB250F has a
14.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized BSI-CMOS sensor . On the other hand, Olympus VR-340 has a
16.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor .
Below you can see the WB250F and VR-340 sensor size comparison.
Samsung WB250F and Olympus VR-340 have the same sensor sizes so they will provide same level of control over the depth of field when used with same focal length and aperture. On the other hand, since Samsung WB250F has 14% larger pixel area compared to Olympus VR-340, it has potential to collect more light on pixel level hence have less noise in low light / High ISO images.