Please refer to below table of encoder resolution.
FASTECH Ezi-SERVO adopts high accuracy of optical encoder and basic resolution is 10,000[[ppr]] then it goes up to Max. 32,000[[ppr]]. 1.8° 2 phase step is used but actual position accuracy is followed by encoder resolution, so compare to conventional 2, 5

phase step motor and other closed loop System, it has very high positioning accuracy. Also it has Perfect position response.

Especially 20mm motor has 4,000 [[ppr]] Encoder and 28mm motor has 16,000[[ppr]] encoder so it guarantees world highest

accuracy. Please see encoder accuracy information according to motor size as below.

FASTECH Ezi-SERVO adopts Min. 10,000[[ppr]] ~ Max. 32,000[[ppr]] High resolution of optical encoder to guarantee the high accuracy.  

Also compare to other Semi-Closed Loop product has only step-out protection purpose, FASTECH product is Full Closed Loop System. Due to high accuracy of product, high precision of stages are the most suitable application with FASTECH solutions with great performances

As seeing as above, even compare to 5 phase step motor (above graph)is very popular in high precision stage market,  Ezi-SERVO (below graph) has around 10 times of  higher positioning than other options. So Ezi-SERVO is the best solution for various types of alignment stages. 

Also FASTECH Ezi-SERVO can adopt external Linear Scale or control Linear Step Motor. so it has very wide range of selection. With Real Time Full Closed Loop control realization, linear scale application and conventional open loop type of Linear Step Motor also can be controlled as Closed Loop to improve position accuracy.