L is for Lens

The lens is among the most fundamental components of the camera. It is the lens that collects light and focuses it onto the film to capture the image.
The most basic lens is a piece of clear glass or plastic with at least one curved side which then bends the path of a light beam. A lens with a convex surface (curved out toward the light source) will cause the light rays to bend toward each other. A concave surface will cause light rays to diverge from each other.
The original camera obscura did not have a lens. Instead there was a tiny hole through which light passed and was bent. This made an image, but it was faint.
The addition of a glass lens meant that the opening could be larger, allowing more light to enter. It also provided better control on the focus of the image.
Today, cameras have elaborate lens systems with multiple, movable lenses of various shapes.

These more complex lenses allow for differing depths of field, adjustment of focus, and make it possible to allow more light into the camera. Professional cameras allow the user to change lenses on their camera for different effects and purposes.
See the other 25 letters of the 2020 A to Z challenge from Animal’s Place by clicking here! All about how cameras work!