function showPrvImage( sImgPath, sImageName ) {
var nWidth = 800;
var nHeight = 600;
var bScroll = 'no';
var nTop = 0, nLeft = 0;
if( nWidth > screen.width-10 || nHeight > screen.height-28 ) {
bScroll = 'yes';
}
if( nHeight < screen.height-28 ) {
nTop = Math.floor( (screen.height - nHeight)/2-14 );
}
if( nWidth < screen.width-10 ) {
nLeft = Math.floor( (screen.width - nWidth)/2 );
}
nWidth = Math.min( nWidth, screen.width-10 );
nHeight = Math.min( nHeight, screen.height-28 );
var wndMyNewWindow = window.open( "about:blank", "", "scrollbars=yes,menubar=no,resizable=yes,width="+nWidth+",height="+nHeight+",left="+nLeft+",top="+nTop );
wndMyNewWindow.document.writeln (""+sImageName+"