The important property of prisms in this article is their ability to redirect light through refraction and reflection. A collection of deck lights used to direct sunlight below deck in ships.

Passenger Lilly Katharine Shipley captured video on Cunard's darkened 'Queen Anne' cruise ship as it passed through the Sulu-Celebes Sea in March ...

deck prisms, and vault lights. These century-old techniques are still being applied today for the diffusion of LEDs or for increasing the brightness of LCD displays.