Support / FAQ / Barcode Terminology

What is SBR (Screen Barcode Readable) Laser Scanner?

In the past there were only two types of barcode scanner: Laser and CCD barcode scanner. The laser barcode scanner has always been treated as more high class than the CCD barcode scanner, due to its elegant laser scan line which makes it easier to aim barcodes, enhancing reading accuracy for the user.  However, the laser barcode scanner has some serious problems:
 
1. Laser beam is harmful to human eyes.
2. Laser can't read on screen barcodes.
3. Laser is fragile due to its moving parts.
 
In light of the above limitations presented by traditional laser barcode scanners, Marson has created a new SBR (Screen Barcode Readable) laser scanner based on Marson's patented technology. Thanks to class 1 laser and configurable brightness, the SBR laser scanner still emits a thin laser beam to enable users with accurate aiming of a barcode, it looks just like a laser scanner but it is not harmful to human eyes. Furthermore, unlike traditional laser barcode scanner, the SBR laser scanner is capable of reading on screen barcodes of smart phone and tablet, and since it has no moving parts, it is more durable than the traditional laser barcode scanner.

Start Character

Start Character is an additional character that marks the beginning (left edge) of a barcode symbol. In connection with the stop character that is how the readability in two directions and the identification of the barcode symbology is made possible.
barcode startcharacter

Stop Character

Stop Character is an additional character that marks the end (right edge) of a barcode symbol. In connection with the start character that is how the readability in two directions and the identification of the barcode symbology is made possible.
barcode stop character

Check Digit / Checksum

A check digit, also known as a checksum character, is the number located on the far right side of a barcode. The purpose of a check digit is to verify the information on the barcode which has been entered correctly. The barcode scanner's decoder calculates the checksum by performing a series of mathematical operations on the digits that precede the check digit, and comparing the result of the calculation to the value of the check digit.
barcode check digit

Quiet Zone

Quiet zone is the blank margin on the either side of a barcode that's used to tell the barcode scanner where a barcode's symbology starts and stops. The purpose of a quiet zone is to prevent the scanner from picking up information that does not pertain to the barcode scanned. (The blank margin will not send a scanning signal hence it named "quiet".) As a rule, the quiet zone should be ten times the dimension of the narrowest element in the barcode (X dimension) or 1/4 inch, whichever is greater. An undersize quiet zone may render a barcode unreadable or readable only from one direction.
barcode quiet zone

Barcode Resolution

Barcode Resolution is the width of the narrowest bar in a barcode, often quantified in the unit of Mil (one thousandth of an inch).

PCS / Print Contrast Scale

PCS is a measurement of the ratio of the reflectance between the bars and spaces of a barcode. PCS is calculated as PCS = (Rs - Rb)/Rs where Rs is the reflectance of the spaces and Rb is the reflectance of the bars.

Symbol Identifier / Code ID

A series of characters, created by the decoder, preceding the transmitted and decoded data; it identifies the symbology as a source of the decoded data.

Scanner Resolution

The scanner resolution is the minimum width of the narrowest bar of a barcode that a barcode scanner is able to read. It is often quantified in the unit of Mil (one thousandth of an inch).

Specular Dead Zone

The specular dead zone is where the light reflecting directly back into the barcode scanner from the barcode that can make decoding difficultly. The specular dead zone is usually up to ± 5° depending on the distance of target and the glossiness of substrate.
barcode scanner dead zone