What is the Best Choice for my Large Format Scanning Application, CCD or CIS?

Traditionally, most large format scanners have used CCD technology to capture the digital image. Now, the latest advances in CIS technology have created opportunities for leading edge manufacturers to design wide format scanners that offer similar performance - scan speed, image quality, resolution and image width - comparable with, or, in some respects, exceeding, the older CCD technology based large format scanners.

Ultimately the decision between CIS and CCD will depend on what you want to do with your large format scanner and how much you want to spend. The basic differences between CCD and CIS imaging technology are described in the notes below. They will help you choose the right type of large format scanner for your application.

Large format scanners using CCD technology will give you an image with a relatively-wide color gamut and a relatively high dynamic range. Color gamut is a measure of how wide a range of different colors the scanner can capture accurately. Dynamic range is a measure of how much detail the scanner can see in dark areas before "blacking out". If you wish to scan photographic-type material and you wish to achieve the best possible reproduction in terms of color integrity and shadow detail, then a CCD scanner is the one for you. CCD scanners also offer greater depth of field, so if your specialisation is scanning books and you want to minimise image deterioration towards the open spine, then choose a large format flatbed scanner which uses CCD technology.

Large format scanners using CIS technology will give you an image with relatively high resolving power and potentially higher geometric accuracy. Resolving power is a measure of how well the scanner can see thin lines or edges. Geometric accuracy is a measure of the spatial accuracy of the image compared to the original document. If you wish to scan black-and-white or color technical documents (such as drawings, maps etc), and you wish to achieve the best possible reproduction in terms of line definition and accuracy, then a CIS scanner is the one for you. CIS scanners also have a far-shorter warm-up time and are far more compact and lightweight, so if you want to be mobile and switch on and start scanning immediately, then CIS technology will enable this.

Of course, CIS scanners provide acceptable color gamut and dynamic range for most users, just as CCD scanners provide acceptable resolving power and accuracy for most users.

So, while the performance of a CIS wide format scanner is similar to that of CCD, it is not the same. For a majority of owners who will use their large format scanner for AEC, CAD and GIS applications, CIS wide format scanners can offer some major advantages.

Learn more about CCD technology and CIS technology.