Which principles of physics does the camera use in order to focus and record pictures?
Project type: Research Project
The purpose of this project is to research the use of lenses as it pertains to photography. I will be developing on this and examining the principles of physics that apply to lenses. Finally I am researching the history and development of the camera, uses of lenses, and the applications and implications. It is important to be able to understand a device used in our everyday life and the principles of physics behind it.
What exactly is a camera lens?
A photographic lens (camera lens) is an system of optical lens elements that are either fixed to the body of a camera or interchangeable. You can compare the photographic lens to a human eye (Fig 2). Basically, it’s an invention that attempts to duplicate the operation of the human eye. The lens sees an image, focuses it, and then transmits its colors, sharpness, and brightness through the camera to the photograph film, which like our memory records the image for processing and future use. The photographic lens is made of optical glass or in some cases plastic.
(As a comparison to the eye) Fig. 2
What is a camera?
The camera is fundamentally made up of a:
- lens (or set of lenses) which is primarily a convex lens that provides the camera with an image from outside of the camera,
- an aperture that controls the amount of light passing through the lens to the film plane,
- a shutter that controls the amount of time that the image is exposed to the film plane and finally
- the film plane where either photographic film or digital receptors allow the image to be created and stored for future viewing/use.
The focus of our research is on the lens but the aperture, shutter and film plane do have significant effects on the resulting image beyond what a lens (or lenses) can do.