An offset alignment method for a micro-lithographic printing device, comprising the steps of: - placing an alignment target substrate on a substrate support of said micro-lithographic printing device; said alignment target substrate having a target pattern presenting areas of at least two different light reflectivities; said target pattern being predetermined, defined relative a target pattern origin point; - illuminating, by a printing head of said micro-lithographic printing device, said alignment target substrate; - measuring light reflected from different points of said alignment target substrate; - creating a reflection image of said target pattern by said measured light, characterized in that said illuminating comprises illuminating said alignment target substrate with a test pattern of light; said test pattern having areas with illumination and areas without illumination; said test pattern being predetermined, defined relative a test pattern origin point; - determining a measured target pattern origin point corresponding to said target pattern origin point from features in said reflection image being associated with said target pattern and determining a measured test pattern origin point corresponding to said test pattern origin point from features in said reflection image being associated with said test pattern; - calculating an offset between a measured position and a written position as the difference between on one hand a difference between said measured target pattern origin point and said measured test pattern origin point, and on the other hand a difference between said target pattern origin point and said test pattern origin point. - placing an alignment target substrate on a substrate support of said micro-lithographic printing device; said alignment target substrate having a target pattern presenting areas of at least two different light reflectivities; said target pattern being predetermined, defined relative a target pattern origin point; said alignment target substrate having a target pattern presenting areas of at least two different light reflectivities; said target pattern being predetermined, defined relative a target pattern origin point; - illuminating, by a printing head of said micro-lithographic printing device, said alignment target substrate; - measuring light reflected from different points of said alignment target substrate; - creating a reflection image of said target pattern by said measured light, said illuminating comprises illuminating said alignment target substrate with a test pattern of light; said test pattern having areas with illumination and areas without illumination; said test pattern being predetermined, defined relative a test pattern origin point; - determining a measured target pattern origin point corresponding to said target pattern origin point from features in said reflection image being associated with said target pattern and determining a measured test pattern origin point corresponding to said test pattern origin point from features in said reflection image being associated with said test pattern; - calculating an offset between a measured position and a written position as the difference between on one hand a difference between said measured target pattern origin point and said measured test pattern origin point, and on the other hand a difference between said target pattern origin point and said test pattern origin point.