LposStatsvLpos.spt is used to measure the autofocus positioning stability.
The script sweeps through all lens positions and samples a few hundred lens position sensor readings at each commanded lens position. The script then displays a graph of the actual lens position versus commanded lens position as well as a graph of the standard deviation of the actual lens position versus the commanded lens position. The standard deviation is a good measure of how well the lens is holding to the commanded lens position.
Ideally, the LposStatsvLpos graph file will look like Example Graph 1. The lower graph should not show any noise and the upper graph shouldn't exceed 0.5um noise, except at the extremes of travel.
If there is excessive noise, then the autofocus will have problems tracking the plate. An example of a bad result is shown in Example Graph 2. Note that the noise exceeds 0.5um in a significant part of the travel.
Organization of LposStatsvLpos_data.txt:
The LposStatsvLpos_data.txt file contains six columns:
