Why do you need to place your Iris 22 that high ?
To have the better holographic experience, you need the eye of the observer to be right under the horizontal line formed by the screen, as it is depicted on this drawing.
Doing so, the observer can’t see the screen and the point of view is perfect to look at the hologram in optimal conditions. If you add an opaque background, the experience will be even more immersive and fascinating for the public.