What is pinhole imaging?

The principle of pinhole imaging is that light travels in a straight line in the same uniform medium without gravity interference, that is, light travels in a straight line. Aperture imaging, about 24,500 years ago, China scholar Mo Zhai, that is, Mozi and his students made the world's first pinhole inverted image experiment, explained the reason of pinhole inverted image, and pointed out the essence of light straight line. This is the first scientific explanation for the straight-line propagation of light.

Blocking a plate with a small hole between a wall and an object will form the reflection of the object on the wall. We call this phenomenon pinhole imaging. Moving the middle board back and forth will change the size of the image on the wall, which shows the nature of light propagating along a straight line. Now some cameras and camcorders use the principle of pinhole imaging. The lens is a small hole through which the scene enters the darkroom and stays on the film.

Aperture imaging is independent of the shape of the hole. The size of imaging is related to the distance from the object to the aperture and the distance from the screen to the hole. If the distance from the hole to the screen remains the same, the farther the object is from the hole, the smaller the image will be. If the distance from the object to the hole is constant, the larger the distance from the hole to the screen, the smaller the image, and vice versa. It can be analyzed by making a light path diagram. For example, the light spots in the forest are all round.