The far field pattern of a laser diode shows an ellipse/line and it seems the accepted explanation for this is that the source is asymmetrical. The thin aspect of the junction causes that axis to have a higher rate of diffraction. However, while that is surly true, nevertheless the expanding beam which is collimnated in a typical pointer/lab laser is focused by a radially symmetrical lens. The optimal focus/collimation must be at best a compromise between the two expansion rates. Is this reasonable? If so maybe some improvement in spot size and shape do this astigmatic component could be achieved if the output of the initial collimnating lens were defocused slightly to allow a secondary lens in the beam path to be inserted to achieve best focus and then slightly tipped to counter the astigmatic component for the diode. Any thoughts?