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repeatability_performance_of_asi_stage [2016/10/04 15:13]
127.0.0.1 external edit
repeatability_performance_of_asi_stage [2018/12/21 10:28] (current)
vik
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 We quantify the point spread of the return locations with the standard deviation for both the X and Y directions. ​ Figure 4 shows a plot of the standard deviation of the return position as a function of the previous move radius.  ​ We quantify the point spread of the return locations with the standard deviation for both the X and Y directions. ​ Figure 4 shows a plot of the standard deviation of the return position as a function of the previous move radius.  ​
  
-[{{ stage_repeatability_4.jpg?​direct&​500 |Figure ​4:  Bi-directional repeatability as a function of move radius for stage with standard rotary encoders using backlash correction routine. ​ Deviation for both X and Y axis are shown.}}]+[{{ stage_repeatability_4.jpg?​direct&​500 |Figure ​4a:  Bi-directional repeatability ​(of a 6.35mm lead screw pitch stage) as a function of move radius for stage with standard rotary encoders using backlash correction routine. ​ Deviation for both X and Y axis are shown.}}] 
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 +[{{ repeat_159.gif?​direct&​500 |Figure 4b:  Bi-directional repeatability (of a 1.59mm lead screw pitch stage) ​as a function of move radius for stage with standard rotary encoders using backlash correction routine. ​ Deviation for both X and Y axis are shown.}}]
  
 It is apparent that the repeatability is better if the moves are smaller. ​ Further improvement can be obtained if linear encoders are used.  Figure 5 shows typical data for a linear encoder stage. It is apparent that the repeatability is better if the moves are smaller. ​ Further improvement can be obtained if linear encoders are used.  Figure 5 shows typical data for a linear encoder stage.
  
-[{{ stage_repeatability_5.jpg?​direct&​500 |Figure ​5:  Bi-directional repeatability as a function of move radius for stage with linear encoders. ​ No backlash correction used.}}]+[{{ stage_repeatability_5.jpg?​direct&​500 |Figure ​5a:  Bi-directional repeatability ​(of a 6.35mm lead screw pitch stage) as a function of move radius for stage with linear encoders. ​ No backlash correction used.}}] 
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 +[{{ repeat_159_le.jpg?​direct&​500 |Figure 5a:  Bi-directional repeatability (of a 1.59mm lead screw pitch stage) ​as a function of move radius for stage with linear encoders. ​ No backlash correction used.}}] 
  
 With the linear encoders, the data now show a difference between the X and Y axis.  The X & Y axis repeatability is less 150 nm for all but the largest moves. ​ This data in Figure 5 was from our very stable MS4000 stage. ​ Inverted stages can show slightly larger repeatability errors on the Y-axis because the crossed roller bearings are slightly shorter and are spaced further apart than the X-axis.  ​ With the linear encoders, the data now show a difference between the X and Y axis.  The X & Y axis repeatability is less 150 nm for all but the largest moves. ​ This data in Figure 5 was from our very stable MS4000 stage. ​ Inverted stages can show slightly larger repeatability errors on the Y-axis because the crossed roller bearings are slightly shorter and are spaced further apart than the X-axis.  ​
repeatability_performance_of_asi_stage.txt · Last modified: 2018/12/21 10:28 by vik