I assume it is a paper thin flexible TV prototype turned into a suite and possibly even a face mask. Connect it to a recorder recording what is behind the man and voila, you see through him from the front.
edit: or in this case, a actual light bending device which would of course render the guy blind while using the device.
edit: or as mentioned, painting the guy or even a simple photoshop here and there
Your link is dead Fernito.