Electrooptical measurement device for ascertaining the relative position of bodies or of surface areas of these bodies

A process for determining the relative position of two bodies or surface areas of bodies with reference to one another, comprising the steps of:

• producing a light beam impact point on a two-dimensional translucent target;
• imaging the light beam impact point on the measurement surface of an optoelectronic target which can be read out two-dimensionally;
• recording of the light intensity for a portion of the pixels of the sensor which are illuminated by the imaged light beam impact point;
• repeatedly determining the median point for the light intensity recorded on the sensor, according to one or two coordinates, as a function of several predefined intensity threshold values;
• determining the functional relationship between the median point and several predefined intensity threshold values;
• determining the plateau area for the functional relationship of the median point to several predefined intensity threshold values, according to at least one coordinate assigned to the optoelectronic target;
• using at least one of a maximum value of the median point or a value of the median point, which value is symmetrical to the plateau boundaries, for defining the best value of the median point of a light spot to be measured;
• and
• determining using use of the best value to determine the mutual relative position of articles.

A method for determining the relative position of two bodies or surface areas of bodies with reference to one another comprising:

• producing a light beam impact point on a two-dimensional translucent target;
• imaging the light beam impact point on the measurement surface of an optoelectronic target which can be read out two-dimensionally;
• recording the light intensity for a portion of the pixels of the sensor which are illuminated by the imaged light beam impact point;
• repeatedly determining the median point for the light intensity recorded on the sensor, according to one or two coordinates, as a function of several predefined intensity threshold values;
• determining the functional relationship between the median point and several predefined intensity threshold values;
• determining the plateau area for the functional relationship of the median point to several predefined intensity threshold values, according to at least one coordinate assigned to the optoelectronic target;
• using at least one of a maximum value of the median point or a value of the median point, which value is symmetrical to the plateau boundaries, for defining the best value of the median point of a light spot to be measured;
• and
• determining using use of the best value to determine the mutual relative position of articles.