The Sanyo LNS-M02 Semi-Long Throw Zoom Lens allows you to change the focal length, which enables a range of projection distances. For this lens, the focal distance is 125 - 162mm. It has a zoom ratio of 1.3:1 and a long-throw ratio of 3.4 - 4.5:1, which is ideal for projecting well-defined, vivid images from a distance. Even smaller sized images projected from far away will be sharp and clear. Installing a zoom lens affords greater flexibility since you can alter the projection distance without actually moving the projector. This is convenient for permanently installed projectors. You can compensate for miscalculations during installation and it's possible to adjust your display proportions depending on class size or type of presentation.