Dualpixel

Dualpixel, commonly referred to as Dual Pixel CMOS AF, is a camera sensor technology developed by Canon. It integrates two photodiodes per pixel to enable phase-detection autofocus on the image sensor, primarily for live view and video. Each pixel’s photosite is split into two sub-pixels, allowing the AF system to compare signals within the same pixel area. This on-sensor phase detection eliminates the need for a separate phase-detection module, enabling faster and more reliable autofocus during live view and while recording video, as well as smoother subject tracking.

Introduced in Canon’s EOS 70D in 2013, the technology has since been used in many Canon cameras, including both DSLR and mirrorless models. The AF system analyzes the phase difference between the two diodes to estimate focus error and drive the lens to correct focus. Because the sensor provides phase information across a broad region, Dual Pixel CMOS AF offers continuous AF for moving subjects and reduces hunting compared with contrast-detection AF alone.

Advantages of the technology include faster focusing in live view and video, improved subject tracking, and smoother rack focusing. Limitations include performance that depends on lighting and lens compatibility, and that some older lenses or firmware may yield less optimal results. The term is often used interchangeably with Canon’s Dual Pixel CMOS AF, though other manufacturers may use different sensor designs that employ dual photodiodes per pixel.