Product

• Lotem^® 800 II Family
• Lotem 800 Quantum
• Lotem 400 Quantum

Cause

During some focus operations in mode 0 with verbose fully enabled (VBS ENABLES FOC 7), an MAE line with an overview of the focus's actions is printed after every three drum revolutions.

Example:

f 03Feb03 21:28:41.922 FOC: MAE = 2200 Max Lpos = 21.700 Min Lpos = -194.800 Mean Lpos = -21.2

The above line contains the following information:

Note: The magnitude of the lens should never appear as an approximation (Lpos<~-175 or Lpos>~175), since this is beyond what can be properly controlled.

Solution

MAE is the mean focus tracking error magnitude. The units are raw focus error units.

Convert the raw focus units to microns, either by finding the correct conversion factor (SET FOC ERRORCAL) or by using 160 raw units per micron as an approximation.

The MAE depends on the media. However, it should be less than 600 during plot with the carriage moving. The lens positions should be within operating range, but that is the only real limitation.
Note: A good MAE can still have a very bad and non-trackable plate bump.

The MAE line is often used in conjunction with the listed focus errors to give insight into what is wrong.

Technical contact(s)

Nir Peleg 

Submitted by

Nir Peleg 

Date submitted

22 June 2003