function openWindow(target, vyska, sirka) {
iMyWidth = (window.screen.width/2) - (350 + 10)
iMyHeight = (window.screen.height/2) - (250 + 25); //450 600
Fokus = window.open("", target,"height=" + vyska + ",width=" + sirka + ",resizable=no,left=" + iMyWidth + ",top=" + iMyHeight + ",screenX=" + iMyWidth + ",screenY=" + iMyHeight + ",scrollbars=no");
Fokus.focus()
}