The Sony DSC-TF1 has a better sensor type than most waterproof cameras that have been available for around the same time as it. This digital camera has a CCD sensor type, whereas most waterproof cameras that have been around for a similar time to it have a MOS sensor type. CCD sensors produce high quality, low-noise images but consume a lot more power than CMOS sensors. CCD is the most common image sensor type used in digital cameras.
A CCD sensor type is actually the best sensor type amongst all digital cameras that have been available for a comparable time to the DSC-TF1.
A MOS sensor type is the worst sensor type amongst comparable types of camera.
It may also be worth also looking at one of the alternative digital cameras that have a CCD sensor currently available including the Panasonic DMC-FT3, the Nikon 31, or the SeaLife DC1400 which has better reviews.