Contrary to popular belief, a digital camera lens is comprised of more than just one lens. A single lens camera would take a picture but would warp the photo. The most significant warping factor is chromatic, which is multiple colors of light bending differently when moving through a lens. Modern cameras overcome this chromatic warping factor by using multiple lenses made of different materials, which treat colors of light differently. In order to zoom on a camera, the lens mechanically adjusts the distance between certain lenses, called the focal length. Focal length is a ratio of how big the subject of the proposed photo is and how far away from the subject you are. Below is a diagram of light entering a camera lens refracting onto a CCD:
Mathematical Application in the Digital Camera
Each camera lens is designed and shaped conically so that the light refracts right in the center by the time it reaches the end of the lens. A conic section is defined as a figure formed by the intersection of a plane and a right circular cone. Depending on the angle of the plane with respect to the cone, a conic section may be a circle, an ellipse, a parabola, or a hyperbola, allowing the picture to come out perfectly shaped. A camera lens shape follows a parabolic shape. Below are examples of conic sections:
Charge-Coupled Device (CCD)
Cameras originally had way to store photos, but it could get tricky with all the wiring an stuff. Kodak proposed to Sasson he assess the potential use of a new thing called a charge-coupled device, or CCD. This CCD introduced a new way to store photos digitally within a camera. These CCDs are silicon arrays with aluminum rows and columns running across them, forming a grid. When a photo is taken, each little grid absorbs the light energy to which it is exposed and "translates" it into binary, which the camera can then retranslate into colors when needed.