-U-
Term (Acronym) [units]: Definition
UXGA (Ultra Extended Graphics Array): A resolution of 1600x1200 pixels.
-V-
Term (Acronym) [units]: Definition
Vacuum Fluorescent Display (VFD): An older emissive display that utilizes vacuum tube technology. Electrons are emitted from a cathode electrode which is selectively controlled by a grid and anode electrode. The electrons collide with a phosphor-coated anode, which emits light. VFDs are used in audio and video systems, clocks, automotive instrument panels, control panels for home appliances, etc. The emission color of a standard VFD is green.
Vertical Alignment (VA): An LC mode that increases viewing angle. MVA and PVA are other similar modes.
Vertical Frequency [Hz]: Also called "refresh rate", this is the number of times per second that an entire display screen is refreshed or redrawn. Measured in Hertz, the vertical frequency of display systems typically ranges from 56 Hz to well over 100 Hz.
VGA: In the very early days of the PC, VGA was an IBM-created acronym for "video graphics array". Now it’s become a word rather than an acronym, and it has only two meanings: (1) a resolution of 640x480 pixels, and (2) the analog video output port (connector) on a PC.
Video Electronic Standards Association (VESA): A group made up of video electronics industry professionals whose purpose is to review proposals and develop standards to promote uniformity and economies of scale in the video electronics industry.
Video Response Time: See Response Time.
Video Wall: An array of multiple flat-panel, CRT or rear-projection displays linked with a videowall processor so that the array can show a single large image or multiple smaller images. The distance between the video cubes in the wall is called a "mullion" and it can be as small as 1-4 millimeters.
Viewable Area: The area of a display which is visible through a bezel or a cutout in the display’s housing. This area is made up of the active area plus a border around the active area. Sometimes a portable device is designed with zero border in order to make the housing as small as possible. This can cause problems if the device is intended to be used with a pen on the screen, such as a Tablet PC.
Viewing Angle: The range of angles over which the contrast ratio of a display exceeds 10:1.
-W-
Term (Acronym) [units]: Definition
Wavelength: The distance between the crests of a wave, or more specifically, the distance in a periodic wave between two points of corresponding phase. The wavelength of visible light is roughly 400 nm to 750 nm. Wavelength in meters is calculated by dividing the speed of light by the frequency (300,000,000/Hz). The higher the frequency, the shorter the wavelength. 400 nm therefore corresponds to high-frequency light (blue, going towards ultraviolet), while 750 nm corresponds to low-frequency light (red, going towards infrared).
White Point: A reference illumination which can be used to define the color white. The white point varies depending on the ambient illumination. For example, photos taken indoors may be lit by incandescent lights, which are relatively red-orange when compared to daylight. Defining white as "daylight" gives unacceptable results when trying to color-correct a photo taken under incandescent lights.
Wobulation: Wobulation, invented by HP, is a technique for reducing the cost and complexity of components required for high-resolution displays. Wobulation works by generating multiple sub-frames of data and projecting them slightly displaced in rapid succession. This allows an effective resolution of 1920x1080 to be obtained from a DMD chip that’s only 960x1080.
-X-
Term (Acronym) [units]: Definition
XGA (Extended Graphics Array): A resolution of 1024x768 pixels. This is currently the most common resolution in laptops as of mid-2006.
