Camera obscura

Optical device

A camera obscura (pl. camerae obscurae or camera obscuras; from Latin camera obscūra 'dark chamber') is the natural phenomenon in which light passing through the small hole of a dark chamber or box will project an image of a scene outside the chamber (box) onto the surface opposite to the hole, resulting in an inverted (upside down) and reversed (left to right) projection of the view outside. Camera obscura refers to analogous constructions such as a darkened room, box or tent in which an exterior image is projected inside or onto a translucent screen viewed from outside. Camera obscuras with a lens in the opening have been used since the second half of the 16th century and became popular as aids for drawing and painting.

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