1.6 Output Devices

  1.6 Output Devices

 

1.6.1 Overview of output devices:

 

Output devices are the parts of a computer system that present processed data from the CPU in a human-readable form. They convert digital signals into text, images, sound, or graphics that users can understand.

 

Examples of Output Devices:

·        Monitor: Displays text, images, and videos.

·        Printer: Produces hard copies of documents.

·        Plotter: Draws high-quality graphics (used in engineering/design).

·        Speakers & Headphones: Produce sound output.

 

1.6.2 Display unit: LED and LCD Monitor,

 

Monitor (Visual Display Unit – VDU)

A monitor, also called a Visual Display Unit (VDU), is the most common output device of a computer. It displays processed data as text, images, graphics, and videos on the screen. The output seen on a monitor is known as a soft copy because it is temporary and can only be viewed on screen.

 

Types of Monitors:

1. Monochrome Monitor – Displays output in a single color (e.g., black & white or green & black).
2. Color Monitor – Displays output in multiple colors, commonly used today

 

LED and LCD Monitors

 

LCD monitor

An LCD monitor is a flat-panel display that uses liquid crystal technology to form images. It consists of two layers of glass or plastic with liquid crystals between them, which align to display text, images, and graphics when activated. LCDs use fluorescent lamps as backlighting.

 

LED (Light Emitting Diode) Monitor

An LED monitor is a modern flat-panel display that uses light-emitting diodes (LEDs) for backlighting instead of fluorescent lamps used in LCD monitors. They are widely used in computers, TVs, and display devices due to their better brightness, color quality, and energy efficiency.

 

1.6.3 Printer: Laser, Ink-jet, Dot-matrix and 3D Printer,

 

Printer

A printer is an output device that produces a hard copy of data or information on paper. Printers are commonly used to print documents, images, and reports from a computer.

 

Types of Printers:

1. Impact Printers
• Print by physically striking ink ribbon on paper.
• Slower, noisy, but cheap.
• Example: Dot Matrix Printer.
2. Non-Impact Printers
• Do not strike the paper; use laser, inkjet, or thermal methods.
• Faster, quieter, and higher quality.
• Examples: Inkjet Printer, Laser Printer.

 

Laser Printer

A laser printer is a non-impact printer that uses a laser beam to form an image on a photosensitive drum, which is then transferred onto paper using toner (powdered ink). It is widely used for producing high-quality, fast, and professional prints.

 

Inkjet Printer

An inkjet printer is a non-impact printer that sprays tiny droplets of liquid ink directly onto paper to produce text and images. It is widely used for everyday printing tasks like documents, photos, and graphics.

 

Dot Matrix Printer

A dot matrix printer is an impact printer that uses a print head with pins. These pins strike an inked ribbon to form characters as a pattern of dots on paper. It is still used for printing bills, receipts, and carbon copy documents

 

3D Printer

A 3D printer is a non-impact printer that creates three-dimensional objects layer by layer using materials like plastic, resin, or metal. It is widely used in manufacturing, design, and prototyping to produce models and custom parts.

 

Speaker

A speaker is an audio output device that converts digital signals into audible sound. It allows users to hear music, voices, alerts, and other audio from a computer or electronic device.

 

1.6.4 Overview of Ports: USB/Type C, HDMI, VGA, Ethernet, Audio port.

 

Peripheral devices are external hardware components connected to a computer to extend its functions. They allow input, output, storage, and communication, making a computer more useful and user-friendly.

 

Categories of Peripheral Devices:

1.     Input devices: Keyboard, Mouse, Scanner.

2.     Output devices: Monitor, Printer, Speaker.

3.     Storage devices: Hard disk, Pen drive, SSD.

4.     Communication devices: Modem, Network card.

5.     Specialized devices: Web camera, Joystick, Barcode reader.

 

Hardware Ports

Hardware ports are sockets on the exterior of the system unit that allow connection between the computer and external devices. They serve as interfaces for data transfer, communication, and power supply.

 

Key Functions of Hardware Ports:

• Connecting peripheral devices (e.g., mouse, keyboard, printer, pen drive).
• Supplying electrical power to low-power devices.
• Transmitting data to and from external devices.

 

Examples of Hardware Ports:

• USB port – connects pen drives, external HDDs.
• HDMI port – connects monitor/TV for high-quality video/audio.
• VGA port – connects monitor (older display standard).
• Ethernet port – connects to wired networks.
• Audio port – connects speakers/headphones.

 

USB Port (Universal Serial Bus)

A USB port is a hardware interface used for short-distance digital data transfer. It is the most common port in computers and allows the connection of many external devices. It is widely used for printers, cameras, keyboards, speakers, scanners, mice, and pen drives. Versions are USB 2.0, USB 3.0, USB-C (faster transfer rates).

 

Type-C Port

The Type-C port is a modern hardware connector commonly found in smartphones, laptops, and tablets. It is small, reversible (can be plugged in either way), and supports fast charging, high-speed data transfer, and connection with multiple accessories.

 

HDMI (High Definition Multimedia Interface)

HDMI is a hardware interface used to transmit high-definition audio and video signals through a single cable. It is widely used to connect devices like digital TVs, DVD/Blu-ray players, gaming consoles, and media devices (e.g., Apple TV) to monitors or televisions.

 

VGA Port (Video Graphics Array)

A VGA port is a standard analog interface used to connect a computer to monitors, projectors, or other display devices. It uses a 15-pin connector to transmit analog RGB (Red, Green, Blue) signals along with synchronization signals. Although an older technology, VGA is still found in many devices.

 

Ethernet Port

An Ethernet port is a hardware interface used for wired Local Area Networking (LAN). It allows computers and devices to communicate with each other by transmitting data packets through Ethernet cables using networking protocols.

 

Audio Port

An audio port, also called an audio jack or audio connector, is used to connect audio devices like headphones, microphones, and speakers to a computer or electronic device. It transmits analog audio signals for both input (recording) and output (listening).