It followed on from the EOS 10D, 20D, 30D and 40D and was followed by the EOS 60D, 70D, 80D and 90D. So many cameras! But ...
Launched in 2013 in the EOS 70D, DPAF improves autofocus speed when using contrast-detect AF. Around 80% of the pixels on the image sensor incorporate two separate light-sensitive photodiodes.