Diplopia is double vision that occurs due to uneven placement of images in both eyes. Normally, when images enter both eyes at the same time, vision can only be accurate if the images come from the same place and at approximately the same time. With diplopia, the image entering one eye is not well compensated by the image in the other eye, and is not perceived as it should be. Diplopia can have a serious impact on a person's quality of vision and make it difficult to perform various tasks.