When the projector is not placed properly, the image projected on the whiteboard may turn out to be a trapezium. When the projector is placed front higher or rear higher, a vertical trapezium is projected. When the projector is placed unevenly on both sides, the projector is not in the center in comparison with the whiteboard, or there is an angle between the projection direction and the horizontal direction of the whiteboard, a horizontal trapezium of another type is formed.

 When the projected image is in the form of a trapezium, the image is distorted and thus should be adjusted.

When a vertical trapezium is projected, you can use the special adjustment button or elevate the projector to make an adjustment (for more information, refer to the projector manuals).

When a horizontal trapezium is formed, you can adjust the location of the projector to the center of the whiteboard to achieve front projection.