The Human eye is a wonderful instrument that relies on refraction and lenses to form images and a camera is similar to it in many ways. The shutter in a camera has the same function as the pupil of the human eye. The pupil is the tiny opening at the center if the iris, which is the colored area of the eye. The purpose of both the shutter and the pupil is to let in light.
The pupil can expand or contract to adjust the amount of light that enters- and a camera's shutter can be adjusted too.
Next, we come to the cornea which is the 'cap' of the eye. It is transparent, sits at the front of the eye, and has a spherical curvature. The lens of a camera is also transparent as it is made of glass. it too is located in the front of the camera, and has a spherical curvature. The lenses of both the eye and a camera can focus and project an upside down image of an object before them.
In a camera, film is used to capture an image. In the eye, the image is focused on the retina, which in turn, converts the image to electrical impulses and sends the information along the optic nerve to the brain.