The camera obscura (Latin; camera for "vaulted chamber/room", obscurafor "dark", together "darkened chamber/room"; plural: camera obscuras or camerae obscurae) is an optical device that projects an image of its surroundings on a screen. It is used in drawing and for entertainment, and was one of the inventions that led to photograph and the camera. The device consists of a box or room with a hole in one side. Light from an external scene passes through the hole and strikes a surface inside, where it is reproduced, rotated 180 degrees (thus upside-down), but with color and perspective preserved. The image can be projected onto paper, and can then be traced to produce a highly accurate representation.The largest camera obscura in the world is on Constitution Hill in Aberystwyth,wales.
The Camera Obscura is an ancient optical device. In its most basic form it is, quite simply, a dark room with a small hole in one wall. On the wall opposite the hole, an image is formed of whatever is outside. This image is upside-down (inverted) and back to front (laterally transposed).
The size of the hole has a great effect on the picture that is being projected. A small hole produces a sharp image, which is dim, while a larger hole produces a brighter picture which is less well focused.This happens because light travels in straight lines, a property known as the rectilinear propagation of light.
The size of the hole has a great effect on the picture that is being projected. A small hole produces a sharp image, which is dim, while a larger hole produces a brighter picture which is less well focused.This happens because light travels in straight lines, a property known as the rectilinear propagation of light.