4 Flashcards
Uses of Monitors
• Interactive Feedback: Display information to the user in real-time.
• Visual Accessibility: Provide visual alerts (e.g., pop-ups) as alternatives to sound, especially helpful for hearing-impaired users.
Advantages of Monitors
• Immediate Feedback: Allows users to see results and system updates instantly.
• User Interaction: Facilitates direct interaction with the computer.
• Customisation:
o Text size can be increased for visually impaired users.
o High-contrast settings improve readability.
o Brightness and colour settings can be adjusted to meet user preferences.
• Flexibility: Content on the screen can be easily modified or updated.
Limitations of Monitors
• Display Quality: Larger monitors typically offer better display quality.
• Portability: Large monitors are difficult to transport.
• Sharing Output: Requires additional devices (e.g., projectors) to share with larger groups.
• Lighting Conditions: Natural light can affect visibility and image quality.
Factors to Consider When Buying a Monitor
Resolution
• Definition: The maximum number of pixels a monitor can display, represented as horizontal × vertical pixels (e.g., 1920 × 1080).
• Aspect Ratio: The ratio of a monitor’s width to its height:
o 4:3 Aspect Ratio: Older, square-like monitors; less suitable for modern media. o 16:9 or 16:10 Aspect Ratios: Widely used today, ideal for movies and gaming.
Factors Influencing Image Quality • Colour Depth:
o The number of bits used to represent a pixel’s colour.
o Higher bit depth = richer colours (e.g., 24-bit colour is better than 16-bit).
• Pixel Density (DPI):
o The number of pixels in a 1-inch horizontal line. o Higher pixel density = sharper, clearer images.
• Refresh Rate:
o How often the screen updates per second.
o Higher refresh rates = smoother motion.
o Low refresh rates = ghosting in fast-moving content (e.g., games or videos).
• Contrast Ratio:
o The difference between the darkest black and brightest white on the screen. o Higher contrast = sharper, more vibrant images.
o Low contrast = dull, muddy visuals.
Troubleshooting Common Monitor Problems
Problem 1: Colours Are Faded, Too Bright, or Muddy Solution: Adjust the brightness, contrast, or colour settings. Problem 2: Blocky or Stretched Images
Solution: Ensure the resolution is set to the recommended setting for your monitor. Problem 3: Screen Displays a Tinted Colour (e.g., Purple, Green, Yellow)
Solution: Check and secure the connection between the computer and the monitor. Replace damaged cables if needed.
Problem 4: Monitor Shows No Display Solution:
• Verify the monitor is turned on and connected to a power source.
• Check the cable connection between the computer and the monitor.
• Ensure the computer is switched on.
• Test the monitor using another device to confirm if the issue is with the monitor.
Speakers and headphones are used for:
• Playing sound: Enjoy music, movies, or other audio content.
• Audible feedback: Hear system sounds or alerts.
• Accessibility: Provide extra features for people with visual disabilities, such as text-to-speech software reading text aloud.
• Communication: Listen to voice messages or interact via software like Skype or other communication tools.
Advantages
• Headphones:
• Speakers:
o Enable private listening without disturbing others.
o Convenient for mobile use, such as listening to music while jogging or commuting.
o Allow groups to hear sound simultaneously.
o Useful for presentations or playing audio in shared environments.
Limitations Speakers and headphones
• Sound Quality: The quality of sound depends on the specific headphones or speakers used.
• Additional Equipment:
o External amplifiers may be needed to produce louder sound for large spaces like classrooms or auditoriums.
• Distractions:
o Speakers can disturb others nearby who are not directly involved.
Troubleshooting Common Problems
If speakers or headphones are not producing sound, here are possible causes and solutions:
Problem 1: No Sound Output
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Problem 2: Speakers Needing Power Not Working
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Problem 3: Low or Mute Volume
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Problem 4: Wrong Sound Output Device
If speakers or headphones are not producing sound, here are possible causes and solutions:
Problem 1: No Sound Output
• Cause: Plugged into the wrong jack (e.g., microphone jack instead of audio-out).
• Solution: Check and connect to the correct audio jack.
Problem 2: Speakers Needing Power Not Working
• Cause: The speakers may be switched off or not plugged into a power source.
• Solution: Ensure the speakers are powered on and properly connected.
Problem 3: Low or Mute Volume
• Cause: The computer’s volume control may be too low or muted.
• Solution: Adjust the sound settings to increase the volume or unmute.
Problem 4: Wrong Sound Output Device
• Cause: The computer may be set to use a different sound output device.
• Solution: Verify and select the correct output device in the sound settings.
Laser Printers
Features
Print black-and-white or colour documents.
• Designed for speed and high-quality text output.
• Best suited for high-volume printing due to low running costs.
Advantages and disadvantages of laser printers
Advantages
• Excellent for sharp, clear text.
• Efficient and cost-effective for large print jobs.
• Produces good quality graphics, suitable for most professional documents.
Limitations
• Not ideal for high-quality photo printing.
• Toner issues:
o Toner isn’t absorbed by the paper, so folding or scraping the printed document may cause the toner to wear off.
• While the graphics quality is good, photo images may look better on a specialised inkjet printer using glossy paper.
Inkjet Printers
Features
Features
• Print black-and-white or colour documents.
• Known for producing the best photo quality when paired with photo-quality paper.
• Affordable upfront cost compared to laser printers.
Advantages and limitations of an inkjet printer
Advantages
• Excellent for photo printing, especially with photo-quality inkjet printers.
• Cheaper to purchase than laser printers.
Limitations
• Higher running costs than laser printers (ink cartridges can be expensive).
• Slower printing speeds compared to laser printers.
• Text print quality is generally lower than laser printers.
• Photo print quality depends on the type of paper used:
o On normal paper, ink may spread and result in blurry images. o Photo-quality paper produces sharp images but is expensive.
Dot Matrix Printers
Features
Advantages
Limitations
Dot Matrix Printers
Features
• Commonly used for point-of-sale (POS) systems, printing receipts, invoices, and similar documents.
• Operate using a printer ribbon and can create carbon copies.
Advantages
• Low upfront and running costs.
• Durable and reliable for basic printing needs.
Limitations
• Low print quality, unsuitable for professional or high-quality documents.
Ink Tank Printers
Features
Advantages
Limitations
Ink Tank Printers
Ink tank printers are a type of inkjet printer that use refillable ink tanks instead of cartridges. They are designed to provide high-quality printing at a lower long-term cost, making them an excellent option for individuals or organisations with high printing demands.
Features
• Use large refillable ink tanks rather than individual cartridges.
• Print black-and-white or colour documents, including photos.
• Ideal for high-volume printing at a lower cost per page.
Advantages
• Lower Running Costs:
o Ink bottles are cheaper and last much longer than traditional cartridges.
o Cost-effective for printing large quantities of documents. • High Print Quality:
o Produces excellent text and photo quality when using proper paper. • Convenient Refilling:
o Ink tanks are easy to refill, reducing waste compared to disposable cartridges. • Eco-Friendly:
o Less plastic waste due to fewer cartridge replacements. • Longer Printing Time:
o Large ink reservoirs mean fewer interruptions for refills. Limitations
• Higher Initial Cost:
o Ink tank printers are more expensive to purchase upfront than standard inkjet printers.
• Drying Out Issues:
o If the printer isn’t used regularly, the ink in the nozzles may dry out, requiring maintenance or cleaning.
• Slower Printing Speeds:
o Similar to inkjet printers, ink tank printers may be slower than laser printers, especially for text-
heavy documents.
• Photo Quality Depends on Paper:
o For professional photo prints, specialised photo paper is necessary.
photo paper is necessary.
Social Implications: Environmental Considerations
Printing has a significant impact on the environment. It is essential to minimise printing and dispose of printing equipment responsibly to reduce harm to the environment.
Why Minimise Printing?
Energy and Carbon Footprint:
Manufacturing paper uses large amounts of energy, resulting in a high carbon footprint. The process also involves poisonous chemicals that are harmful to the environment.
• How to to Reduce Impact:
Print only when necessary: Avoid printing unless absolutely required.
Double-sided printing: Use both sides of the paper to reduce waste.
Two pages per sheet: Print two pages on one side of a sheet to save paper.
Lower resolution: Use draft mode or lower resolution to reduce ink or toner usage.
• How to o
o o o
Manufacturing paper uses large amounts of energy, resulting in a high carbon footprint. The process also involves poisonous chemicals that are harmful to the environment. Reduce Impact:
Print only when necessary: Avoid printing unless absolutely required.
Double-sided printing: Use both sides of the paper to reduce waste.
Two pages per sheet: Print two pages on one side of a sheet to save paper.
Lower resolution: Use draft mode or lower resolution to reduce ink or toner usage.
Proper Disposal of Printers and Cartridges
• Environmental Hazards:
o Printers and cartridges contain harmful chemicals that can seep into the soil and groundwater if disposed of in landfills.
o These chemicals can cause significant environmental damage. • Recycling Solutions:
o Do not throw old printers or cartridges into regular trash.
o Recycle them at designated facilities that handle electronic waste.
o Many manufacturers and stores offer recycling programmes for printers and cartridges.
Troubleshooting Printer Issues
If your printer is not working or printing properly, consider these possible causes:
- Power Issues:
o The printer is not plugged in or switched on. - Connection Problems:
o The printer is not correctly connected to the computer. - Low Ink or Toner:
o Faded or irregular printouts may indicate that the ink or toner is running low. - Wrong Printer Selection:
o Ensure the correct printer is selected in the print dialogue box. - Network Settings (for network printers):
o Incorrect network configurations may prevent the printer from functioning. - Incorrect Printer Driver:
o If the wrong printer driver is installed, the printer might print unreadable or mixed-up text and
images. 7. Paper Issues:
o Using the wrong type of paper can cause:
▪ Inktospread,creatingblurryprints. ▪ Tonertonotadhereproperly.
o Paper jams may also occur. If this happens, remove the paper carefully to avoid damaging the printer.
Printer Considerations
When choosing a printer, it is essential to consider factors like cost, paper compatibility, system compatibility, network connectivity, and mobility. These factors impact the printer’s efficiency, versatility, and suitability for specific needs.
Speed
• Printer speed is measured in pages per minute (ppm).
• The quoted speed is based on printing a page with around 5% surface coverage and minimal graphics.
• Higher ppm ratings indicate faster printers, ideal for high-volume tasks.
Colour Printing
• Colours are created by blending Cyan (light blue), Magenta (light purple), and Yellow inks or toners.
• Combining all three colours produces black, but this is inefficient.
• CMYK Printers:
o Most colour printers use four inks (Cyan, Magenta, Yellow, and Black).
o Separate cartridges for each colour are better, as they allow you to replace only the depleted
colour.
o Printers with combined cartridges waste ink, as all colours must be replaced together when one runs out.
Resolution
• Measured in Dots Per Inch (dpi):
o Indicates the number of dots the printer can create along a horizontal line. o Higher dpi produces cleaner and crisper images.
• Standard Resolutions:
o 300 dpi is sufficient for text printing.
o Higher resolutions are only necessary for high-quality graphics or photo printing.
• Considerations for Higher Resolutions:
o Effective only when printing on special photographic paper. o More expensive: Uses more ink or toner.
Cost Per Page
• Definition: The cost to print one page, calculated as an average based on approximately 5% page coverage.
• Implication: Lower cost-per-page printers are ideal for high-volume printing.
Paper Considerations
• Paper Type:
o Laser Printers: Toner doesn’t bond well with rough or bumpy paper.
o Inkjet Printers: Ink can spread and blot on very absorbent paper.
o Solution: Use specialised paper for better quality, especially when printing photos.
• Paper Size:
o Most desktop printers handle A4 paper.
o Larger models can print up to A3 size for larger documents or posters. System Compatibility
A printer must work with your operating system, which depends on the availability of compatible drivers.
• Operating System Support:
o Most printers come with drivers for Windows and macOS.
o Linux: Check for driver availability if you use this operating system.
Network Connectivity Wireless Functionality:
• Printers with built-in WiFi can join a network, making them accessible to all devices on that network.
• Some printers allow mobile devices (smartphones and tablets) to print directly via the network. Bluetooth Printing:
• Certain printers enable mobile devices to print directly via Bluetooth, eliminating the need for WiFi. Cabled Connections:
• Some printers include Ethernet ports for connecting to a wired network. This makes the printer accessible to all devices on that network without requiring WiFi.
Mobility
• Portable Printers:
o Some printers are designed for mobility, with batteries that allow them to function without a fixed power supply.
o Limitations:
▪ Often have reduced print quality and limited paper size options.
• Recommendation:
o Unless mobility is essential, opt for a compact inkjet or laser printer for better overall performance.
Printing
3D printing allows you to create physical, three-dimensional objects from digital designs made using CAD (Computer-Aided Design) or 3D modelling software.
There are many types of 3D printers, each using different methods and materials, including plastic, resin, concrete, steel, and even chocolate.
This rapidly evolving technology is now used to print?
:
• Buildings and structures (e.g., bridges, houses).
• Mechanical parts (e.g., gears and machine components).
• Human body parts and prosthetics (e.g., artificial hands, legs, joints, and bones).
• Everyday items (e.g., tools, clothes, furniture, and more).
Advantages of 3D Printing
Limitations of 3D Printing
Advantages of 3D Printing
• Fast and cost-effective prototyping – allows designers to test ideas before mass production.
• Custom parts can be printed on demand, reducing the need for large spare part inventories.
• Enables the creation of complex and unique designs that traditional manufacturing methods cannot
produce.
Limitations of 3D Printing
• High initial costs – 3D printers and materials can be expensive, though they are often cheaper in the long
run than traditional prototyping.
• Slow printing process – depending on the object, printing can take hours or even days.
• Noise and odour – some 3D printers are loud and emit strong smells, especially when melting plastic.
• Requires technical skill – setting up and calibrating the printer correctly is essential for high-quality prints.
Troubleshooting 3D Printer Issues
If a 3D printer is not working correctly, check for the following:
• Issues with the 3D Model:
o The design file may contain errors that affect printing.
• Heating Problems:
o The printer’s heating element may be faulty or not reaching the correct temperature.
• Printing Speed Issues:
o The printer may be running too fast or too slow for the material being used.
• Material Issues:
o The filament or resin may be defective or unsuitable for the printer.
