This article got nothing to do with The Sharper Image even though it is about sharper image ;)
Especially sharper digital images.
By its nature, digital images from every digital cameras are slightly blurry. This is because virtually all digital camera have an anti aliasing filter in front of the sensor, such a filter involves a trade-off among sharpness. Why do we need this filter? Read about it here.
The anti aliasing filter is also known as an optical low-pass filter.
Some cameras like certain Canon models used TWO low-pass filters!