var imgsLeft = new Array( '2.jpg', '3.jpg','d.jpg','c.jpg');
var imgsRight = new Array( '1.jpg', '5.jpg','e.jpg','a.jpg');
var pos  = 0;
function chImg()
{
pos++;
var iLeft = document.getElementById( 'imgFieldLeft' );
 iLeft.src = './styl/wybor/' + imgsLeft[pos-1];  
 
 var iRight = document.getElementById( 'imgFieldRight' );
 iRight.src = './styl/wybor/' + imgsRight[pos-1]; 
 
 if( pos >= 4 )    
 { pos = 0;     
 } 
 
  
   
window.setTimeout( 'chImg()', 2000 );
}