Recognition systems Cambridge IGCSE Information & Communication Technology revision
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In plain words
Recognition systems let a computer identify something without anyone typing: a pencil mark, a number plate, a tag on a pallet, a face. Each uses a different technology, and each has a job it does best.
6 things to know
- Optical mark recognition (OMR) reads marks in set positions on a form. It is used for school registers and multiple-choice exam papers. It is very fast and accurate, but forms must be designed and filled in carefully.
- Bar codes and QR codes are read optically to identify items. A QR code holds more data and can be read by a phone.
- Optical character recognition (OCR) reads printed characters. Automatic number plate recognition (ANPR) uses a camera and OCR to read vehicle number plates, for car parks, tolls and catching speeding drivers.
- Radio frequency identification (RFID) uses radio waves to read a tag. It is used to track stock, in passports, to identify vehicles and animals, and in contactless payment. The tag need not be seen, and many tags can be read at once.
- Near field communication (NFC) is a very short-range form of RFID, used to pay with a smartphone.
- Biometric recognition identifies a person by the face, iris, retina, finger or thumb print, hand or voice. It is unique to the person and cannot be forgotten, but the equipment is expensive, and some people see it as an invasion of privacy.
Worked example
A car park wants to let cars in and out without tickets, and charge the right amount. Which system should it use, and how does it work?
- Automatic number plate recognition.
- A camera photographs the number plate as the car enters. OCR software turns the image into text, which is stored with the time.
- When the car leaves, the plate is read again and matched, and the charge is worked out from the time between.
Tips and tricks
- ANPR is a use of OCR. If asked how it works, say: a camera captures an image, and OCR converts the characters to text.
- Biometrics: an advantage (unique, cannot be lost or forgotten) and a disadvantage (expensive, privacy concerns) will answer most questions.
It lands in your notebook with its questions as flashcards.
Recognition systems: 5 questions and answers
These are the quiz’s questions. Do the quiz first, then come back here for the ones that got you.
Which technology is used to read number plates?
ANPR systems use a camera and optical character recognition.
Which technology reads pencil marks on a multiple-choice answer sheet?
It detects marks in set positions.
Which is true of RFID?
Radio waves pass through packaging.
Which is used to pay with a smartphone held near a reader?
Near field communication works over a few centimetres.
Which is a biometric method?
It uses a feature of the body.
Quiz
5 questions
Tap an answer and you’ll see straight away whether it’s right, and why.
Worksheet
2 questions, 5 marks. Write your answers on paper, then check them.
Recognition systems
Cambridge IGCSE Information & Communication Technology 0417 · 5 marks · papermunch.org
Name ______________________________ Date ______________
Give two uses of RFID.[2]
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Tracking stock in a warehouse. Contactless payment. (Also: passports, identifying vehicles.)
Give two advantages and one disadvantage of biometric recognition compared with a password.[3]
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Advantages: a biometric feature is unique to the person; it cannot be forgotten or shared. Disadvantage: the equipment is expensive. (Also: an injury may stop the feature being recognised.)
Answers: Recognition systems
- 1. Tracking stock in a warehouse. Contactless payment. (Also: passports, identifying vehicles.)
- 2. Advantages: a biometric feature is unique to the person; it cannot be forgotten or shared. Disadvantage: the equipment is expensive. (Also: an injury may stop the feature being recognised.)