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Fujifilm Super CCD’s
Digital imaging sensors normally employ square pixels in a grid like fashion on the CCD (charged coupled devices) chip. Fujifilm has created a Super CCD sensor utilizing octagonal pixels as opposed to squares, in an attempt to group them closer in the grid. See the following diagram.

The distance "d2" between the centers of two octagonal pixels is smaller than the distance "d1" between two conventional square pixels, resulting in a finer resolution and larger pixels.

The difficulty of placing pixel wells so close to each other is the problem known as bloom. Bloom is when light energy spills over from one pixel well to another, thus diluting contrast rather than improving the image. Fujifilm addressed the bloom or infectious noise problem with their software and additional circuitry. As you will see in the illustration below the new 4th generation of sensors have the large octagonal pixels continuing from 3rd generation Super CCD HR and there is an additional smaller octagonal R pixel linked to the larger S pixel.

The larger S type pixels deal with imaging Sensitivity and the smaller R type pixels extends the Range. Fuji claims that the new S/R chip has 4 times greater dynamic range over previous chips.

Design Theory for the Fujifilm Super CCD SR image sensor

Fujifilm used regular silver halide film as a guide to building their new Super CCD SR imaging sensor. Film has small and large silver halide crystals. They capture highlight and shadow more efficiently due to various size of grains. Fuji tried to duplicate the differing size of the silver halide grains by using different sized pixles. The S pixel is the larger of the two and captures the shadows and mid tones. The smaller R pixels captures the highlight details and thereby extends the images range.

The new FinePix S 20 pro utilizes the new SR imaging chip, in a 6 megapixel size. Upcoming later this year Fujifilm will ship the S 3 pro with the super CCD SR chip in a 12 megapixel size.

The following shows the difference between CCD HR and CCD SR

Single pixel layout significantly enhanced resolution for those that need it.

SR pixel layout Greatly expanded dynamic range with latitude and tonality approaching film

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