The iris acts like the aperture of a camera lens.
In a camera the following parts could be considered equivalent to the parts of a human eye:Optical diaphragm = IrisAperture in optical diaphragm = PupilOuter lens element / lens glass = CorneaInner lens element = Eye lensCCD Sensor (in a digital camera) = RetinaThis is a huge simplification of a very complex topic. Please see the related links for more information.
A camera's diaphragm and your eye's iris perform the same function in the same way. They both control how much light is allowed through the lens by expanding and contracting.
The iris diaphragm is named after the iris, the colored part of the eye, because of its similar appearance and function. Just like the iris controls the amount of light entering the eye, the iris diaphragm in a camera lens controls the amount of light entering the camera.
The iris. - - - - - No. It's the eyelid. The shutter's function is to completely stop light from reaching the film (or the sensor, if you have a digital camera with a mechanical shutter). The iris in your eye cannot do this--only the eyelid can.
The iris is like the aperture part of a camera, which used to also be called the iris.
A camera lens.
It is identical in action to the iris in your eye, it widens and narrows to allow only the required amount of light through the aperture hole/pupil
the iris
A pinhole camera works by allowing light to pass through a small hole (the pinhole) and onto a light-sensitive surface inside the camera. The pinhole acts like a lens, focusing the light to create an image. The image is then captured on the surface, such as film or a digital sensor, without the need for a traditional lens.
Lens does not belong, as it is not part of the structures involved in the formation or regulation of the aqueous humor within the eye like the ciliary body, iris, and suspensory ligaments.
If you have photographic memory then your eye functions like a camera in a way
no. its lens like glass for you to see far or near