To enable the printing of 50 A4 pages per minute, Canon's high-speed full-color copying machines use the Quattro Engine, a four-drum system with a structure similar to that of a printing press. The engine incorporates one photosensitive drum for each of the CMYK colors, with the four drums configured in series to transfer images by color in sequence for full-color printing. With a high-speed four-color system, however, even the slightest errors in the laser-emission timing, tilt of the laser beams for each color, or magnification can result in color misalignment. Canon has developed various auto-registration servomechanisms to prevent the occurrence of misaligned colors.

For example, a CCD sensor measures the degree of any color misalignment immediately after printing and a built-in computer instantaneously computes the amount of correction required. The optical system then adjusts accordingly, moving vertically and laterally as needed in microscopic 5 µm increments to ensure proper alignment.

In addition, the system achieves improved image definition in units of single dots thanks to visible-light ultra-small spot lasers, and delivers greater precision accuracy for image density and tonality through automatic gradation control and Dual ATR (Attenuated Total Reflection), which controls toner density.