CAMERA Obscura (i.e. Dark Chamber), in Optics, a machine or apparatus representing an artificial eye, by which the images of external objects, received through a double convex glass, are exhibited distinctly, and in their native colours, on a white matter placed within the machine, in the focus of the glass. The invention of this instrument is due to Friar Bacon, though by some it has been ascribed to Baptista Porta.
The camera obscura affords very diverting spectacles, by representing images perfectly like their objects, while at the same time it exhibits all their motions. By means of this instrument, a person unacquainted with designing may delineate objects with the greatest accuracy. Its use in photography will be found under that head.