http://www.northlight-images.co.uk/article_pages/cameras/1ds3_af_micoadjustment.html

Mako Koiwai writes: “This is very cool! Download the interference pattern … don’t print it … use it on your screen … for checking focus …I emailed it to my iPhone, saved the file/image … it will reside in your Photos folder, where you can retrieve it and use it as a Focus Aid … for instance your 2nd could hold it up next to the talent’s eyes or you could place it next to ones tabletop product.

http://www.northlight-images.co.uk/article_pages/cameras/1ds3_af_micoadjustment.html