Font size
Worksheets3. Hardware - Input & Output Devices: Computer Science CIE IGCSE
Total questions: 52
Worksheet time: 36mins
How many input devices do humans use?
(a)
Select the input devices
Barcode scanner
Digital camera
keyboard
actuator
DLP projector
Select the input devices
microphone
optical mouse
QR code scanner
injet printer
laser printer
Select the input devices
touch screen
2D scanner
3D scanner
LED screen
speaker
Carries out small, very dedicated processes
microprocessor
embedded system
integrated circuit
actuator
Captures an image in a digital camera
CCD
CIR
Lens
ADC
What does CCD stand for?
Charge Couple Device
Capacitive Crystal Display
Cloned Covered Denary
Colin Creevey Dances
Made up of hundreds of sensors that act as photodiodes
LCD
CCD
LED
ADC
What is a sensor in a CCD called?
Microprocessor
Photodiode
Pixel
LED
Increasing the number of pixels...
Increases image quality
Decreases image quality
What is used to form a digital image array once the picture has been captured by a CCD?
ADC
DAC
LED
DLC
What two binary patterns are produced by the ADC? (Digital camera)
Levels of brightness
Colour
Shape
Size
Resolution
What colour system do most cameras use?
24 bit
16 bit
8 bit
RGB system
CYMK system
What is a digital image stored on?
CCD
SD card
HDD
SSD
What is image file size determined by?
Number of pixels
Size
Resolution
Level of brightness
What could a low number of pixels result in?
(a)
What does image quality depend on?
Recording device lens and sensor array quality
Number of pixels used
Light levels
How image is stored (JPEG, raw file, etc)
Picture resolution (8 bit, 16 bit, etc)
How many megapixels does a professional camera use?
(a)
How many megapixels does a phone camera use?
(a)
What is used to transfer digital image files?
USB port
Bluetooth
Drag and drop
Text
What are advantages of digital cameras?
Image can be seen immediately - no development time required
You can take as many images as your data storage will allow.
Cheap
Image can be pixelated easily
Cheap
What are advantages of digital cameras?
Backup copies of the image can be made
Image can be easily shared
Image can be easily edited
Image can be easily deleated
Image can be retaken more than once
Are touch screens input or output devices?
input
output
both
neither
How many types of touch screen are there?
(a)
What are the types of touch screen?
Capacitive
Resistive
Infra-red
Light emitting diode
Liquid Crystal Display
What is used to determine where the screen is touched?
x-y coordinates
the em spectrum
electricity
signals
What does a capacitive touch screen use to detect a finger?
The natural electrical signals all living things have in their bodies
Pressure
Temperature
Disturbance
What is a capacitive touch screen made of?
A layer of glass (protective layer)
A layer of air or inert gas (usually argon)
A layer of transparent electrode (conductive layer)
A glass substrate
Flexible polyethlyne
What do the layers in a capacitive touch screen act as?
A capacitor
A transistor
An electrode
A pointing device
How many types of capacitive touch screen are there?
(a)
What are the types of capacitive touch screen
Surface
Finger
Projective
Stylus
Resistive
What measures changes in voltage in a capacitive touch screen?
Photoelectric cell
Microcontroller
Microprocessor
CPU
What are disadvantages of digital cameras
Small number of pixels means a bad quality image
Accidental/ malicious sharing of images
Images take up a large amount of storage space
Require high technological skill
Expensive
Which type of capacitive touch screen allows a multi-touch facility?
Surface
Projective
What are advantages of capacitive touch screens?
Good screen visibility
Better image clarity
Very durable (high scratch resistance)
Work even with gloves
Multi-touch capacity
What are disadvantages of capacitive touch screens?
Only work with bare fingers/stylus
Sensitive to EM radiation
Dull in bright sunlight
poor screen visability
How many layers does a resistive touch screen have?
(a)
What does a resistive touch screen use to detect a finger?
The natural electrical signals all living things have in their bodies
Pressure
Temperature
Disturbance
What is a resistive touch screen made of?
Glass
A layer of air or inert gas (usually argon)
A layer of transparent electrode (conductive layer)
Resistive coating X 2 (Usually indium tin oxide)
Flexible polyethlyne
What does a resistive touch screen use to detect a finger?
The natural electrical signals all living things have in their bodies
Pressure
Temperature
Disturbance
What are the layers of a resistive touch screen?
Flexible polyethene
Resistive coating (usually indium tin oxide)
glass substrate
Conducive layer
What are the layers of a resistive touch screen?
AIr/argon (inert gas)
Glass
protective layer
glass substrate
What converts a voltage to digital data and sends it to the microprocessor in a resistive touch screen?
Microcontroller
Indium tin oxide
Microprocessor
Embedded system
What are advantages of resistive touch screens?
Good resistance to water and dust
Durable
Can be used with a gloved hand
Allows multi-touch facilities
What are disadvantages of digital touch screens?
Low touch sensitivity
No multi-touch capacity
Poor screen visibility in strong sunlight
Vulnerable to screen scratches
Only work with bare fingers/special stylus
What types of sensors does an infrared touch screen use?
Heat
Optical
Infrared
Pressure
Temperature
What does an infrared touch screen use to detect touch?
An array of sensors
Infrared transmitters
Pressure
Capacity
What are advantages of infrared touch screens
Allow multi-touch facilities
Good screen durability
Gloves can be used
Good resistance to dust and water
cannot be accidentally activated
What are advantages of infrared touch screens
Good screen visability
Operability unaffected by scratched/ cracked screens.
Easy to use with a computer
Good resistance to dust and water
cannot be accidentally activated
What are the disadvantages of infrared touch screens?
Screen can be sensitive to water/moisture
Possible for accidental activation to occur.
Sometimes sensitive to light interference
Low touch sensitivity
Vulnerable to screen scratches
What are advantages of touch screens
User friendly
Good for small and large devices
Save space as no keyboard and mouse are used
Used in multiple areas
Extremely precise
What are disadvantages of touch screens?
Can be imprecise
Damaged screens may not work
Addictive
Can smash easily
