3 Basic Video Displays

Response Time

speed which an individual pixel can change state on-off or from one colour to another

Refresh Rate

# of times per second in which the entire display draws the data

Backlighting

illuminates a pixel with light source from behind

Zone/Local Dimming

selective control over backlight to improve contrast

Contrast Ratio

difference b/t the max & min brightness of a display

1000:1 (white is 1000x brighter than black)

OLED Contrast Ratio

Infinite

Best Contrast Ratio

Higher the better

Lumen

how much light is given off in all directions

measures efficiency

Candela

visible intensity from light source in specific direction

Lux

how bright surface will be reflecting

Nit

unit of measurement of luminance

for brightness of monitors

amount of light given off in a specific direction per area

1 nit = 1 candela/m²

Indoor LCD Display Nits

300 nits

Outdoor LCD Display Nits

2000 nits

CRI

Colour Rendering Index

100 means light source shows the same colour as it would under natural sunlight

CRI ranges over 90 are best

Display vs. Monitor

displays are used to view

monitors are used to evaluate

4 Displays that Generate Own Light

Cathode Ray Tube (CRT)

Plasma Display Panel (PDP)

Organic Light Emitting Diode (OLED)

MicroLED

3 Displays that Need a Light Source

Liquid Crystal Display (LCD)

Digital Light Projection Display (DLP)

LED Projectors

CRT

Cathode Ray Tube

obsolete

LCD

Liquid Crystal Display

requires backlight

inefficient

liquid crystal has to move to change state of pixel

DLP

Digital Cinema Projectors

needs external bulb

OLED

Organic Light Emitting Diode

pure blacks

vulnerable to degrading

vulnerable to burn in

high contrast ratio

wider viewing angle

wide colour gamut

emissive layer creates light

conductive layer carries control info (turns pixels on & off)

response times: 1000x faster than LCD

no moving parts

MicroLED

tiny light emitting diode

versatile sizes

increased brightness (10K nits)

doesn't burn in

long lifespan

doesn’t need colour filters

expensive

no moving parts

each pixel needs 3 LEDs

great colour gamut

Quantum Dots Filters

active tiny quantum dots pass more accurate colours than normal LCD panel filters

QLED

LCD

efficient use of backlight

good for 10 bit colour

bigger gamut than most LCDs

Swiss Cheese & Olives

Micro LEDS & OLEDs

electrons fall into (+ve) holes into energy banks spitting out photons

TFT Layer

thin film transistor

layer of crystals in LCD display

Polarising Filter

controls the direction of light wave motion passing through anLCD display panel

Twisted Nematic LCD

liquid crystals get twisted

electric current must be off for light to pass thru subpixel