The foundation of imaging science as a discipline is the "imaging chain" – a conceptual model describing all of the factors which must be considered when developing a system for creating visual renderings (images). In general, the links of the imaging chain include:
The human visual system. Designers must also consider the psychophysical processes which take place in human beings as they make sense of information received through the visual system.
The subject of the image. When developing an imaging system, designers must consider the observables associated with the subjects which will be imaged. These observables generally take the form of emitted or reflected energy, such as electromagnetic energyormechanical energy.
The capture device. Once the observables associated with the subject are characterized, designers can then identify and integrate the technologies needed to capture those observables. For example, in the case of consumer digital cameras, those technologies include optics for collecting energy in the visible portion of the electromagnetic spectrum, and electronic detectors for converting the electromagnetic energy into an electronic signal.
The processor. For all digital imaging systems, the electronic signals produced by the capture device must be manipulated by an algorithm which formats the signals so they can be displayed as an image. In practice, there are often multiple processors involved in the creation of a digital image.
The display. The display takes the electronic signals which have been manipulated by the processor and renders them on some visual medium. Examples include paper (for printed, or "hard copy" images), television, computer monitor, or projector.
Note that some imaging scientists will include additional "links" in their description of the imaging chain. For example, some will include the "source" of the energy which "illuminates" or interacts with the subject of the image. Others will include storage and/or transmission systems.
