20 min read

Output Devices

Monitors, printers of every kind, speakers and projectors — and what the numbers on their specifications mean.

Monitors

A monitor is the main output device. Its specification includes: Size — measured diagonally in inches (e.g. 24"). Resolution — the number of pixels: Full HD 1920 \times 1080, QHD 2560 \times 1440, 4K UHD 3840 \times 2160. More pixels give sharper text and images. Panel type — IPS panels show accurate colours at wide viewing angles (good for design); VA gives deep contrast; OLED gives perfect blacks but costs more. Colour gamut — how much of a colour range such as sRGB or Adobe RGB it can show. Designers preparing print work want close to 100% of sRGB or wider. Refresh rate — how many times a second the picture updates (60 Hz is fine for office work; gamers use 144 Hz or more).

Speakers and headphones turn digital audio into sound. A projector shows the screen image on a wall — for classrooms and meetings. Actuators such as motors, pumps and buzzers are outputs in control systems (like the water-tank pump in the logic course).

Practice

Which monitor resolution has the most pixels?

Monitors

A monitor is the main output device. Its specification includes: Size — measured diagonally in inches (e.g. 24"). Resolution — the number of pixels: Full HD 1920 \times 1080, QHD 2560 \times 1440, 4K UHD 3840 \times 2160. More pixels give sharper text and images. Panel type — IPS panels show accurate colours at wide viewing angles (good for design); VA gives deep contrast; OLED gives perfect blacks but costs more. Colour gamut — how much of a colour range such as sRGB or Adobe RGB it can show. Designers preparing print work want close to 100% of sRGB or wider. Refresh rate — how many times a second the picture updates (60 Hz is fine for office work; gamers use 144 Hz or more).

Printers

Sound and Projectors

Speakers and headphones turn digital audio into sound. A projector shows the screen image on a wall — for classrooms and meetings. Actuators such as motors, pumps and buzzers are outputs in control systems (like the water-tank pump in the logic course).

Practice

Which monitor resolution has the most pixels?