Large-area optical element

A display system, comprising:

• a light source;
• a spatial light modulator configured to modulate light from the light source;
• an optical element having a dimension on the order of approximately 0.5 m positioned to at least partially receive and transmit light modulated by the spatial light modulator;
• and
• a projection element for projecting light modulated by the spatial light modulator and transmitted by the optical element onto a display surface for presenting a visual image to a viewer;
• wherein the optical element comprises:
• a monolithic container fabricated from a transparent material, wherein the monolithic container has a plurality of optical surfaces including an entrance face, a first face, and a second face opposing the first face, the faces shaped and positioned such that light entering the container through the entrance face may be reflected by both the first and second faces before passing through the first or second face;
• and
• a liquid positioned and sealed within the monolithic container, wherein the liquid has a density substantially less than a density of the monolithic container and wherein the liquid has an index of refraction that is approximately equal to the index of refraction of the container.