In the human eye, light enters through the pupil and is focused onto the retina by a lens. The amount of light hitting the retina is determined by the iris, which controls the diameter and size of the pupil.
ImageMaster® VR systems replicate this function of the biological eye. A camera with adjustable focus transmits the generated test images to an image sensor. The camera takes over the function of the human pupil and the image sensor the tasks of the retina.