chp 3 Flashcards
two types of light projectors
DLP (digital light projector) and LCD (liquid crystal display)
Digital Light Projectors
millions of micromirrors on a small digital micromirror device –> the number of micromirrors and the way they are arranged determines the resolution of the image
when they tilt towards the light source, they are on
they switch on and off creating various grey shades (1024)
a birght light passes through a colour filter, so the mirrors can produce different colours –>
Liquid crystal display
high intensity beam of light passes through a LCD display (from bulb or LED)
sent to chromatic coated mirrors, that reflect the light back at different wavelengths (RGB)
then the light passes through LCD screens, which block and leave some light
3 images are produced, and then they are recombined using a prism
advantages of DLP
- higher contrast ratios
- higher reliability/ longevity
- quieter running
- smaller and lighter
- better suited to dusty/smoky
advantages of LCD
gives a sharper image
better colour saturation
more efficient energy use
less heat
disadvantages of DLP
no grey components
shadows when moving image
colour definition is usually worse
diasvantages of LCD
bad contrast ratios
limited life
degrade with time
LCD screens advantages
They have low power consumption and run at a cool temperature
They do not suffer image burn or flicker issues
They provide bright images and colours
They are cheaper to produce than LED screens
LED screens advantage
They do not need backlighting which makes them thinner and lighter to hang on the wall
LED screens are replacing LCD displays in TVs, monitors, laptops and mobile devices
They have better image quality and a longer life span
They can be used to create very large screens that can be used to show visual content at events such as football matches and music festivals
They consume very little power making them suitable for being switched on for many hours in the day
OLED adv
Much thinner and lighter than traditional LCD screens
Use organic light emitting diodes (OLEDS).
They use organic carbon compound to create semiconductors
No form of back lighting is required
You can have very thin, flexible screens
Speakers
name 14 sensors
acoustic, temperature, pressure, moisture, pH, accelerometer, flow, gas, humidity, infra-red, level, light, magnetic field, proximity
