so at the grid.column.text.setfocus, when i use "this" it has the value "osdi.omainscr.page6.disb1.disb1grid.column1.text1".

Actually, it doesn't. THIS, just passes an object type variable, not a string containing the object name and containership hierarchy.

Whatevever function receives the variable can use the reference to call any exposed method of that object.