Display
A display is technology that sends out visible light to show images or information and is meant to be viewed by the human eye. It can be a near-eye display or a traditional display. Displays create light according to the state of a connected control system, such as a digital state machine or an analog electronic circuit. A display can also be called a visual display, a dynamic visual display, or an electronic visual display.
Displays can be point based, ray based, or wave based. Ray based devices are based on rays or ray cones, which have a point of origin and a direction of the ray. Ray cones also have a growth rate.
Displays can be classified on their coordinate frame relative to the eye or eyes: World fixed display and head-fixed display. A world fixed display exists in the world, like a laptop, a TV, or a smartphone. A head fixed display is mounted to the head, meaning when you turn your head it stays in front of your eyes. Head fixed displays include VR headsets and the Google Glass and devices from Vuzix. Head-fixed displays that display a virtual reality or augmented reality experience must refresh at a fast enough rate to avoid VR motion blur. This is a higher requirement on refresh rate than a world-fixed display.
The most important features for a display to be useful are field of view, contrast (both static and dynamic and in color), and focal depth capability.
Common digital state machines include computers.
Traditional computer systems typically use 2D displays, which have a fixed focal depth.
Technology[edit]
There are various methods and architectures of dynamic visual displays.
Display technology typically refers to a specific implementation of real physical parts that have been proven to be manufacturable.
Types of display technology include:
By representation[edit]
Display devices can be point based, ray based, or interference based. Point and ray based displays can be studied using ray optics. Interference based displays must be examined using wave optics. Point based devices are based on point sources. These include laptop screens, televisions, and smartphone screens.
Point based[edit]
Ray based[edit]
Interference pattern based[edit]
Interference based devices are also called holographic devices. The display device modulates light as in wave optics that interferes with itself and forms a pattern at some distance. This is the rarest type of device.