Olympus TG-320 has a
14.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor and features TruePic III+ processor. On the other hand, Nikon AW100 has a
16.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CMOS sensor .
Below you can see the TG-320 and AW100 sensor size comparison.
Olympus TG-320 and Nikon AW100 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 Olympus TG-320 has 15% larger pixel area compared to Nikon AW100, it has potential to collect more light on pixel level hence have less noise in low light / High ISO images.