var fDesc=new Array(); fDesc[0] = "PreDesigner is a handy tool designed to help you assess and illustrate the key paraxial parameters for an imaging system.
It was designed for students, teachers, sales engineers and optical designers and is useful for learning and teaching fundamentals of optical design."; function tShowHide(id, show) { var s = document.getElementById("desc"); if ((s.innerHTML.length<=212 || show==1) && show!=2) { s.innerHTML = fDesc[id]; if (document.getElementById('m1')) document.getElementById('m1').style.display='none'; if (document.getElementById('m2')) document.getElementById('m2').style.display='none'; if (document.getElementById('more_txt')) document.getElementById('more_txt').style.display='inline'; } else { s.innerHTML = ''; } }