Leonardo da Vinci studied the camera obscura, an optical device that projects an outside scene into a dark chamber.
A camera obscura consists of a darkened space or box with a small opening. Light entering through the opening forms an inverted image of the scene outside on the opposite surface. Leonardo described and illustrated this principle in his notebooks while investigating vision, light, perspective, and the structure of the eye.
The camera obscura was not a camera in the modern photographic sense. It created a temporary image but had no film or electronic sensor to preserve it. Artists and scientists could use the projected image as an aid for studying shapes and perspective.
Leonardo’s interest also helped connect optical science with artistic practice. The device predates photography by centuries, and its basic principle remains related to how simple pinhole cameras work.