Presentation no:1

Scanners And Reading Devices

INTRODUCTION TO COMPUTING

Aqsa Bibi SP11/BBA/013

Huma Rehman SP11/BBA/038

Ch Ateeq Ullah Zafar SP11/BBA/020

Danial Ahmed SP11/BBA/021

Fareeha Khalid SP11/BBA/031

Group Members:

• It is a device that optically scans images,printed

text,hand wrighting or an object and converts it to a digital image.

Scanner:

Types of Scanner:1. Flatbed scanner2. Sheetfed Scanner3. Pen scanner4. Drum scanner

Flatbed scanner:• It is also called desktop scanners.• They are versatile.• Commonly used scanners.• In fact this article will focus on the technology as it

realates to flatbed scanners.• Flatbed scanners are dominating the market now .• The flatbed can scan pages while still attached in the

book or magzine.• It can scan portions of documents larger than the

scanner bed(like maps)

Sheetfed Scanner:• Sheetfed are similar to flatbed scanners except the document is moved by the scan head is immobile.• A sheetfed scanner looks a lot like a small portale

printer.

Pen scanner:• It is used as the same way you use a marker highlighter.• Simply take the pen scanner across the text.• The pen scanner will let you scan,store and transfer

your printed text as well as smaller images to your computer.its ideal for taking notes or scanning text for students that use a text reader.

Drum Scanner:• It is used by the publishing Industry to capture incredibly detailed images.• They use a technology called (PMT) photomultiplier

tube.• In PMT,the document to be scanned is mounted on a

glass cylinder.At the center of the cylinder is a sensor that splits light bounced from the document into three beams.each beam is sent through a colour filter into a photomultiplier tube where the light is changed in to an electrical signal.

1. Barcode Readers

2. RFID Readers

Reading Devices:

Barcode Reader:

• A barcode reader (or bar code scanner)is an Electronic device for reading printed barcodes.

How Barcode Reader works?

• A typical Bar Code Reader consists of Scanner, Decoder, and Cable.

• The Scanner scans the Bar Code symbol and captures the bars and spaces of the bar code and sends it to the decoder.

• The decoder translates the bars and spaces into corresponding electrical output and transmits that data to the computer in a traditional data format.

Types Of Barcode Readers1. Pen wand

2. Slot scanner

3. CCD Barcode scanner

4. Laser Scanner

Pen Wand:

• The simplest barcode reader. It contains no moving parts and is known for its durability and low cost.

• User has to remain in direct contact with the bar code

• It must be held at a certain angle and has to be moved over the bar code at a certain speed.

Slot Scanner:

• A slot scanner remains stationary and the item with the bar code on it is pulled by hand through the slot.

• Slot scanners are typically used to scan bar codes on identification cards.

• Time and attendance, factory data collection and access control are a few of the applications for a slot scanner in the workplace.

CCD Barcode Scanner

• CCD stands for (charge couple device) • A CCD scanner has a better read-range than the

pen wand.• It is used in retail sales.• Typically, a CCD scanner has a "gun" type interface

and has to be held no more than one inch from the bar code.

• Several readings are taken to reduce the possibility of errors.

• A disadvantage of the CCD scanner is that it cannot read a bar code that is wider than its input face.

CCD Barcode Scanner

Laser Scanner:

• A laser scanner, either hand-held or stationary, does not have to be close to the bar code in order to do its job.

• It uses a system of mirrors and lenses to allow the scanner to read the bar code regardless of orientation, and can easily read a bar code up to 24 inches away.

• To reduce the possibility of errors, A laser scanning may perform up to 500 scans per second.

• They are capable of reading a bar code up to 30 feet away.

Laser Scanner:

RFID(Radio Frequency Identification): RFID is a technology that uses communication via radio waves to exchange data between a reader and an electronic tag attached to an object,for the purpose of identification and tracking.

RFID(Radio Frequency Identification):• RFID Makes it possible to give each product in a grocery store its own unique identifying number, to provide assets,people,Work in process,Medical devices etc.

•All with unique identifiers like the license plate on a car but for every item in the world.

•Radio –frequency identification involves hardware known as interrogators(also known as readers), and tags(also known as labels),as well as RFID software.

MOST RFID Tags Contains atleast two parts:

• One is an integrated circuit for storing and processing data, modulating and demodulating a radio frequency .

•The other is an antenna for receiving and transmitting the signal

Types of RFID depending on mobility1. Fixed RFID

2. Mobile RFID

FIXED RFID•If the reader reads tags in a stationary position,it is called fixed RFID•These fixed readers are set up specific interrogation zones and create a BUBBLE of RF(radio frequency) energy.•This allows a very difinitive reading area for when tags go in and out of interrogation zones.

Mobile RFID• If the reader is mobile when the reader reads tag,it is called mobile RFID.• Mobile readers include handhelds, carts and vehicle mounted RFID readers from manufacturer such as Motorola,sirit etc

TYPES OF RFID TAGS

1. Passive RFID tags

2. Active RFID tags

3. (BAP) RFID tags

Passive RFID tags

• Which have no power source and require an external electromagnetic field to initiate a signal transmission.

Active RFID tags

• Which contains a battery and can transmit signals once an external source(interrogator)has been successfully identified.

(BAP) RFID TAGS• Which require an external sourace to wake up but have significant higher forward link capability providing greater range.