The camera obscura, also sometimes called the “optical chamber”, is a known device consisting of a closed box with a pinhole, thus capable of projecting light, through which the projection of an image is verified in the projection plane, usually located behind.

For more information on how a camera obscura works, you can read the entry on Wikipedia or look at the explanation in the video below.

According to some hypotheses, the camera obscura would have already been used by man in the more remote past, through the use of holes on curtains or screens made on animal skin, thus inspiring some forms of Paleolithic art, such as cave paintings.

An interesting example of how light was already used in various ingenious contexts is reported in the ancient Chinese mathematical treatise Zhoubi Suanjing (written probably around 1046-771 BC), where the use of pinhole projections from solar rays was reported, such for by observing the position of the luminous circle it would have been possible to understand the time.

In the opinion of some scholars, the ancient use of the darkroom would have been carried out by the sorcerers and the priests of the temples, to “evoke” demons, divinities or spirits through the projection.

In any case, “the official report” of the invention of the camera obscura seems to have always been of Chinese origin: in fact inside the mozi, ancient Chinese writings attributed to Mo Di and dating back to around 476 BC – 221 BC where the theory of Mohism is exposed together with various theories on meritocratic governance, growth and economic theory and impartiality, the description of a camera obscura is given. Inside the writings, it is explained how the inversion of the image works through the projection and the collection by means of a pinhole camera.

The camera obscura will then be described also in the West by Aristotle (384 BC or 383 BCE – Chalcis, 322 BCE) in the 4th century BC.