Chapter 4 Flashcards
(25 cards)
What are the types of Video Display Units?
CRT LED LCD Plasma OLED Projection systems p. 199
How does CRT work?
An electron gun shoots a beam of electrons toward the back side of the monitor screen p. 199
What are two ways to measure CRT monitors’s image quality?
Dot Pitch
Resolution. p. 200
Define Dot Pitch
The measurement between the same spot in two vertically adjacent dot trios. p. 200
Define Resolution
The number of sofware picture elements (pixesls) that are used to draw the screen. p. 200 It is common setting among CRT., LCD and projections systems.
What are two types of LCD displays that have been implemented over the years?
Active matrix screens and passive matrix screens and dual scan which is a passive matrix variant. p. 201
Describe Active Matrix
An active matrix screen is made up of several independent LCD pixels. A transistor at each pixel location activates two opposing electrodes that align the pixels crystals and alter the passage of light. p. 201
Describe Passive Matrix
There is no dedicated transistor for each pixel but instead a matrix of conductive traces. (a single pixel) it sends a signal across the x and y coordiate traces the interesect at the pixel turning it on. p. 202.
Describe Dual Scan
It is a variation of the pasive matrix display. It is split in half to implement a dual scan display. Each half is refreshed separeltly leading to increased quality. p. 202
Describe LED display
LCD panels with light emitting diodes (LEDs) as light sources instead of bulbs used by LCD monitors. Its basically and LCD but called LED for marketing purposes. p. 203
Describe Plasma Displays
Plasma refers to a cloud of ionized particles. This electrical imbalance is used to create light from the chnages in energey levels as they achieve balance. The cloud is created from an inert gas such as neon by placing electrodes in front of and behind sealed chambers full of gas and vaporized mercury. p. 203
Describe OLED Displays
OLED are the image producing parts instead of the light source like LED. It works on the same principle as Plasma by placing an excitable material between two electrodes. An organ light is emitted. p. 204 Like LCD it is an active matrix. AMOLD
Describe Super AMOLD
The touch sensor panel TSP in the LCD and AMOLED displays are removed and replaced with an on cell TSP that is thinner. This leads to more visible screen and more sensitivity to touch panels. p. 205
What advantage Super AMOLD plus have over Super AMOLD?
It employs 1.5 as many elements (subpixels) in each pixel and it is 18% more energy efficient. p. 206
What is a lumen?
A unit of measure for the total amount of visible light that the projector gives off, based solely on what the human eye percieves.
Define Refresh Rate
The vertical scan frequency. It specifies how many tiems in one second the scanning meam of electrons redraws teh Screen in CRTs. The phosphors stay bright for a fraction of asecond, so they must be constantly hit with electrons to appear to stay lit to the human eye. p. 209 Large monitors need 85 Hz and higher.
Define Resolution
The number of horizontal dots by the number of vertical dos that make up the rows and columns of your display. p. 213
Describe multimonitor feature dual view
When you have multiple displays. As of Vista, WDDM verstion 1.0 one driver must be used for all adapters. p. 215
Define degaussing.
The reduction of the magnetic field of an object. It makes previosuly saved information all but unrecoverable. p. 217
What causes you to have to degause your monitor?
The constant bombardment of metalic shadow mask of the CRT monitor by the electron beams causes magnetic fields to build up. p. 218
What are 5 primary groups of video standards?
Monochrome, GGA, EGA, VGA, DVI, HDMI and other modern digital video. p. 221
Describe Monochrome video technology
Black and white. p. 221
What does EGA stand for?
Enhanced Graphics adaptor. p. 222
What are some advanced video resolutons and concepts?
Super VGA, XGA,.
