Difference between real and distance measured using ruler

edited February 2010 in Layout

During the work with klayout I've encountered a problem.
While the line width is 1um as seen in the properties window. The ruler says it's 2um.

When checking all structures, I discovered that all of them are twice bigger than their real size.

See attached picture, if it's possible to attach it here..

Thanks, Moshe.


  • edited November -1

    Hi Moshe,

    I think there is a difference in the interpretation of the database unit. Basically, the width of any structure is stored as multiples of the database unit. Unfortunately there are two such units (I assume you are using GDS).

    Could you check the database units on the layout's property page? It's found in the File menu, "Layout Properties" menu entry. It should feature two lines, i.e.

    Database unit in user units 0.001
    Database unit in meter 1e-09

    Usually, user units are micron and both numbers are related by a factor of one million. I have seen cases where this correspondence was broken which could explain unexpected measurement results.

    Best regards,


  • edited November -1
    Hi Matthias

    The resolution of the GDS file was double.

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