peripheral devices

1. Welcome
to our
Presentation
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2. Presentation on : Display Devices and Storage Devices.
Course Name : Computer Peripheral And Interfacing.
Course code : CSE3205
Submitted by, Submitted to,
Avijit Paul Id: CE18017 Rahmina Rubaiat,
Jotirmoy Roy Id: CE18028 Lecturer, Department of CSE
Md Abdul Mukit Id: CE18040 MBSTU, Tangail-1902
Chanchal Saha Id: CE18048
Anirban Chanda Id: CE18055
Samiul Haque Id: CE18019
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3. Contents
# CRT
# CRT work & display
# Advantages and Disadvantages of CRT
#LCD
# Advantges and Disadvantages of LCD
#Floppy Disk
# Advantages and Disadvantages of Floppy Disk
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4. CRT
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5. What is CRT ?
• CRT is the abbreviation of Cathode Ray Tube.
• It is a vaccum tube containg an electric gun ( a source of electrons ) and
a fluorescent screen , with internal or external means to accelerate and
deflect the electron beam , used to create images in the form of light
emitted from the fluorescent screen.
• The image may represent electrical waveforms ,pictures , radar targets
and others.
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6. How CRTs work & display ?
• A CRT monitor contains millions of tiny red,green and blue phosphor
dots that glow when struck by an electron beam that travels across the
screen to create a visible image.
• In a CRT monitor tube , the cathode is a heated filament.
• The heated filament is in a vaccum created inside a glass tube.
• The electrons are negative and the screen gives a positive charge so the
screen glows.
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7. Cathode Ray Tube
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8. How CRTs work & Display
• The heated filament which heats a cathode , which emits electrons by
thermionic emission.
• These electrons are then attracted through a large potential difference to
a positive anode.
• The anode has a hole in the center through which a beam of electrons
flows.
• The x and y plats can apply an external field to deflect this beam.
• The beam then this a fluorescent screen and is deteced as light.
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9. Advantages of CRT
• The cathode rayed tube can easily increase the monitor’s brightness by
reflecting the light.
• They can produce more colours.
• The CRT monitors have lower price rate than the LCD display or plasma
display.
• The quality of the image displayed on a CRT monitors is superior to the
LCD and Plasma monitors.
• The colour features of the CRT monitor are considerd highly excellent.
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10. Disadvantages of CRT
• They have a big back and take up space in desk.
• The electromagnetic fields emitted by CRT monitors causes a health
hazard to the functioning of living cells.
• CRTs emit a small amount of X-ray radiations which can result in a
health hazard.
• Constant refreshing of CRT monitors can result headache.
• CRT operate at very high voltage which can overheat system or result in
an implosion.
• They are heavy to pick up and carry around.
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11. LCD
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12. Liquid Crystal
• A state of matter which has properties between those of
conventional liquids and those of solid crystals.
• For instance , a liquid crystal may flow like a liquid but its
molecules may be oriented in a crystal-like way.
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13. What is LCD ?
• A liquid crystal display (LCD) is a flat electronic display panel used as a
visual display aid.
• It uses liquid crystals to create a visual effects on screen.
• LCDs do not generate light on their own but rely on sunlight or room
light to generate images with the help of liquid crystal.
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14. Advantages of LCD
• Brightness: Produces very bright images due to high peak intensity. Very
suitable for for environments that are brightly lit.
• Emissions: Produce considerably lower electric, magnetic and
electromagnetic fields than CRTs.
• Geometric distortion: Geometric distortion at the native resolutions .
Minor distorton may occur for other resolutions.
• Power consumption: Energy efficient. Consume less than 1/3 the power
of a comparable CRT.Consumes less electricity than CRT and produce
little heat.
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15. Advantages of LCD
• Screen Shape: Completely flat screen.
• Sharpness: At the native resolutions, the image is perfectly sharp.
Adjusments are required at all other resolutions which can result in
mesurable degradation to the image.
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16. Disadvantages of LCDs
• Aspect ratio: The aspect ratio and resolution are fixed .
• Contrast: Lower contrast than CRTs due to a poor black level.
• Cost: More expensive than CRTs.
• Viewing anlge: Restricted viewing angles.Viewing angles affect the
brightness , contrast and colors shown. Wide angle can leed to contrast
and color reversal.
• Resolution: Works best at the native resolution. The native resolution can
not be changed.
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17. Floppy Disk
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18. What is floppy disk?
• Floppy disk is a storage medium capable of holding electronic data, like
a computer file.
• It was created in 1967 by IBM.
• Some types of floppy disk
– 8-inch drive
– 5¼-inch drive
– 3½-inch drive
– Zip drive
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Floppy disk:

20. How does a floppy disk store data?
• A floppy drive is a magnetic medium that stores and reads data on the
floppy disk using a read head.
• When a 3.5" floppy diskette is inserted into the drive, the metal slide
door is opened to expose the inner magnetic disk.
• The read/write head uses a magnetic polarity of 0 or 1.
• Reading this as binary data, the computer can
understand what the data is on the platter.
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22. Advantages of floppy disk
• Portable & inexpensive
• Small & cheap
• Easy to carry
• Easy to transport and handle
• Useful for transferring a small file
• It can be used to transfer data from one computer to another computer
• Secure tab to stop data from being overwritten
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23. Disadvantages of floppy disk
• The access time of floppy disk low
• Small storage capacity
• Heat can be also damaged floppy disk
• Many new computers don’t have any floppy disk drive
• Data can be erased if the disk comes into contact with a magnetic field
side
• Slow to access and retrieve data when compared to a hard-disk device
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24. Thank you.
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