To increase your comfort a zoom facility is available. You can enlarge an indicated portion of the document by clicking on the zoom icon. A rectangular “magnifying glass” is placed in the preview of the current page. It is possible to resize it by using the bottom-right corner of its container. There are two operation modes of zoom function. The first one is to drag a rectangle containing a detailed preview. The second mode (”full screen” mode) is enabled if you resize the “magnifying glass” to the size of the preview. Click on the zoom icon again to hide the magnifying glass.