var scrWidth = screen.availWidth;
var scrHeight = screen.availHeight;

function openWin(winWidth,winHeight,winPath,winName) {
var winXpos = (scrWidth-winWidth)/2;
var winYpos = (scrHeight-winHeight)/2;
newWin=window.open(winPath+".htm",winName,'width='+winWidth+',height='+winHeight+',top='+winYpos+',left='+winXpos ,scrollbar='yes');
newWin.focus();
}