For the projection aspect, a San Diego company called AV Concepts used a variation of a visual effect that was discovered in the 19th century, known as Pepper's Ghost.

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"Pepper's ghost" isn't the sort of phrase you hear very often at a show like SXSW. In amongst all the latest generation technology, there aren't too many folks discussing hundreds years old optical concepts.

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One difference: In the Victorian era, Pepper's Ghost was normally used to reflect actual, physical objects or actors, making them appear "dimensional" in ways that the projected or computer-generated imagery typically used today do not.

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