Grade one physics question: Why does the camera have a black box?

If the light reflected from a bright scene enters a dark room through a small hole, a dim scene image can be formed on the wall opposite the scene. This image is upside down, because the light from the upper part of the object can only shine on the lower part of the wall, and the light from the lower part can only shine on the upper part of the wall. This is the well-known principle of black box.

A sealed box has a small hole on one side, and the scenery outside the box passes through the small hole, forming an opposite reflection on the completely dark inner wall of the box. This is the earliest form of camera. There is also black-box operation, that is, private operation, not to let others know.

Extended data:

A device for mounting a photographic film on a camera. Its structure is tight, opaque, and there are also black-box operations: it refers to private operations, not letting others know, and it can also be used as a metaphor for the secrecy of the owner's psychological activities.

Photography was discovered and applied to description. Images should not be time-consuming and laborious, but can be saved in a better way.

Thus, the method of photosensitive storage was invented. Photographic machines and tools such as cameras, photographic materials such as photographic negatives, developers, and even images change from black and white to color.

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