Absolute electric rotary encoders have 17 bit resolution

Netzer Precision DS-25 absolute electric rotary encoders provide many advantages, including 17 bit resolution and < 0.025° accuracy. The lightweight miniature devices provide analog Sin/Cos,Digital SSi,BiSS-C output options. Products come with hollow floating shaft, as well as no bearing or other contact. Devices come with total weight of 4gr and a low profile of 7mm. http://www.electromate.com