A viewscreen, also known as a holoscreen, was a device for displaying images or information for the view of an audience. The main component of a viewscreen was the alloy transparisteel, which was made of the mineral lommite.
The Trade Federation used rippling circular viewscreens aboard its Lucrehulk-class battleships. Darth Vader Force choked Admiral Kendal Ozzel at a great distance while seeing him through a viewscreen. Pentagonal viewscreens were common in the Galactic Empire, as exemplified by those aboard the first and second Death Star, aboard the the Super Star Destroyer Executor, and in the shield generator bunker on Endor.
- Ultimate Star Wars, New Edition