10-05-2014, 02:39 PM
Barcode
Barcode.pptx (Size: 763.6 KB / Downloads: 14)
A Bar Code is just a different way of encoding numbers and letters by using a combination of bars and spaces of varying widths.
A Bar Code is just another way of entering data into a computer.
A bar code is a reference number that a computer uses to look up an associated record that contains descriptive data and other important information.
For example
A barcode found on a soda can does not contain the product name, type of soda, or price, instead, it contains a 12-digit product number.
When this number is scanned by the cashier at the check-out, it is transmitted to the computer which finds the record associated with that item number in the data base.
The matching item record contains a description of the product, vendor name, price, quantity-on-hand, etc.
The computer instantly does a "price lookup" and displays the price on the cash register.
It also subtracts the quantity purchased from
the quantity-on-hand.
This entire transaction is done instantly.
EAN-13
EAN-13 is used world-wide for marking retail items.
EAN-13 is used where the country code is required.
This code is composed of 2 numbers for country code.
10 numbers for data characters and one for checksum.
The checksum calculation:
Add the values of the digits in the even-numbered positions: 2, 4, 6, etc.
Multiply this result by 3.
Add the values of the digits in the odd-numbered positions: 1, 3, 5, etc.
Sum the results of steps 2 and 3.
The check character is the smallest number which, when added to the result in step 4, produces a multiple of 10.
Laser Barcode Scanners
The laser barcode scanner sends a low energy laser beam to read between a pattern on the image space and the beam moves backwards and forwards by means of a mobile mirror which in turn causes a blinking effect and one can see the reading line moving over the barcode.
This reflection
returns and is then
read by the fixed
mirror in the
scanner.
Limitations Of Barcode
The amount of data it stores.
It is also expensive especially (Inkjet type Barcode).
Barcode can not be printed on light dark surface.
Barcode fonts have limitations on sizing.
Barcode must have only alphabets and number only.