function show_submenu(){
	var obj = document.getElementById('submenu_main');
	
	obj.style.visibility = 'visible';
}

function hide_submenu(){
	var obj = document.getElementById('submenu_main');
	
	obj.style.visibility = 'hidden';
}

function MM_preloadImages() { //v3.0
	var d=document; if(d.images){ if(!d.MM_p) d.MM_p=new Array();
    var i,j=d.MM_p.length,a=MM_preloadImages.arguments; for(i=0; i<a.length; i++)
	
    if (a[i].indexOf("#")!=0){ d.MM_p[j]=new Image; d.MM_p[j++].src=a[i];}}
}

function preloadImg_standard(){
	MM_preloadImages('images/submenu/vertical_off.png');
	MM_preloadImages('images/submenu/horizontal_off.png');
	MM_preloadImages('images/submenu/linear_off.png');
	MM_preloadImages('images/submenu/rotary_off.png');
	MM_preloadImages('images/submenu/technologies_off.png');
	
	MM_preloadImages('images/submenu/vertical_on.png');
	MM_preloadImages('images/submenu/horizontal_on.png');
	MM_preloadImages('images/submenu/linear_on.png');
	MM_preloadImages('images/submenu/rotary_on.png');
	MM_preloadImages('images/submenu/technologies_on.png');
}