Inside the Digital Camera

Digital Camera Cross Section The digital camera

is a complex device The only part that is

the same as film cameras is the lens.

Taking a Picture – Step 1 Camera is aimed at

the scene Light reflected from

the image passes through the lens of the camera.

The lenses in digital cameras are different form those used in film cameras

Camera Lens Construction The quality of a lens

is determined by the manufacture and the construction.

Lens construction consists of elements, individual lenses placed in groups.

The lens at the right has 16 elements in 5 groups

Digital Camera Cross Section

Taking a Picture – Step 2 The image is

focused on a device that is sensitive to light.

The majority of cameras us Charged Coupling Devices (CCD)

Some cameras use CMOS devices.

CCD Sensors

Bayer Array To capture color images, each sensor

on a CCD has to have a filter placed over it which only allows penetration of a particular color of light. 

Virtually all current digital cameras can only capture one of the three primary colors in each sensor so they discard roughly 2/3 of the incoming light.

The most common type of filter arrangement is the Bayer Array, based on how the human eye sees light.

Taking a Picture – Step 3 CCD generates an

analog signal that represents the image

Taking a Picture – Step 4 The Analog to Digital

Convertor changes the analog electrical signal into digital information.

ADC

Taking a Picture – Step 5 The Digital Signal

processor converts the information into the file output information.

ADC

DSP

Taking a Picture – Step 6 The file information

is sent to the flash storage media in the camera.

ADC

DSP