The field of view of an iPhone’s camera: 1/4″ opening, expanded to 7.5 x 9″ at 8.5″ from the lens.
Early Box Cameras
Researching a camera build of my own, above are some very early cameras. They all share the same box-like construction with a simple lens and a plate onto which the image is focused.
Via (from top to bottom): ClassicCameras blog, Metfilter, kodaksefkeblog, Flickr user gunthert, and BigShotCamera