Hi guys, I have been wondering for a while so to how it is possible to make devices that move only thousands of an inch. Does anyone know? I have asked my prof at school but his specialty wasnt that. One examle that comes to mind is the mill and leath machines. check this out: http://science.nasa.gov/headlines/y2004/21jul_llr.htm [Broken] People on earth shoot a laser and wait for it to come back in order to find the distance and the precision has to be freaking accurate. i have been wondering since i watched a documentary 3 years ago. I need some answers, please. thanks.